Agnieszka Pusz , Magdalena Paulina Wiśniewska , Dominik Rogalski
Various factors can lead to the transformation of metal forms and to an increase in their solubility and, consequently, their mobility. One solution to the problem of increased solubility is the use of carbons as additives to soil in order to limit the potential migration of contaminants. The aim of this study was to determine the effect of using brown coal and activated carbon on metal forms that are available to plants. The mineral composition of the coals used in a pot experiment was analyzed. Observations were carried out with a JJSM-6380 LA scanning electron microscope (SEM) connected to an EDS electron micro-probe. The total contents of Zn, Cd, Pb and Cu in the assessed soils as well as the content of available metal forms were determined after single extractions with different reagents, namely 1 M NH4NO3, DTPA and 1 M HCl. Generalized linear models (GLMs) were used to evaluate the effectiveness of the stabilization methods in a long-term pot experiment. The carbons reduced the percentage of these forms relative to the total metal content in the soil. After adding brown coal, Zn, Cd, Pb and Cu forms were reduced by up to 32%, 30%, 33% and 43%, respectively. After adding activated carbon, the metal forms of Zn, Cd, Pb and Cu were reduced by up to 47%, 44%, 40% and 50%, respectively. The following order of extracted metal forms with different solutions was found: HCl: Zn > Pb > Cu > Cd; DTPA: Pb > Zn > Cu > Cd; NH4NO3: Zn > Cu > Pb > Cd. Eight years after setting up the pot experiment, the contents of humic substances in soils with the addition of both tested carbons were compared, and the soils with added carbons were found to have a stable content of humic fractions. The costs of remediation through the stabilization method using the tested brown coal and activated carbons do not exceed USD 75/t (taking into account the double doses of both carbons).
Maria Grodzka-Łukaszewska , Zofia Agnieszka Pawlak , Grzegorz Igor Sinicyn
The aspects of surface stability and groundwater exchange recognized by many researchers due to the intensification of agriculture and industry (manifested in, e.g., regulation and dredging of riverbed sediments of rivers) are now widely discussed on the international forum of water policy and management. It is essential to assess the spatial variability of water exchange through the river length and cross sections for the preparation of data and calculation of the groundwater flow model. This article presents research which describes the spatial distribution of the surface water-groundwater interaction within the river cross-section. Two measurement series were carried out to describe its variability. Additionally, a groundwater flow model was developed to simulate and represent the variable nature of water exchange in the hyporheic zone in the river’s cross-section. The model was successfully verified by means of measurements of water flux in the hyporheic zone. The precise spatial description of this variability is the first step to determine the possibility of introducing this variable in an accurate manner, within the limits of measurement uncertainties or simulation assumptions, in the construction of mathematical models of groundwater flow.
Leszek Ornoch , Paweł Popielski , Andrzej Olszewski , Adam Kasprzak
Building inclinations can be measured through the use of ultrasonic hydrostatic levelers. These are used to measure long-term relative displacements of vertical parts of structures and utilize the principle of communicating vessels (similar to the classic water scales). The presented ultrasonic displacement measurement technique was developed by Ultrasystem in the 1990s and was applied to several objects in Poland. Long-term measurements enabled the development of a model of object behavior under the influence of various factors. Among these are the annual cycle of temperature changes, fluctuating water levels, turbine chamber emptying, etc. Such a model can facilitate the prediction of failure based on the appearance of changes deviating from typical behavior (e.g., a much stronger dependence of the inclination as a function of the water level). The results obtained with the help of ultrasonic sensors enable the observation of subtle deformations of the object, which is valuable when developing and calibrating new models of the object (e.g., by means of the finite element method).
The main goal of this paper is to evaluate the burst pressure and structural integrity of a steel pipeline based on in-line inspection results, in respect to the grouping criteria of closely spaced volumetric surface features. In the study, special attention is paid to evaluation of data provided from the diagnostics using an axial excitation magnetic flux leakage technology in respect to multiple defects grouping. Standardized clustering rules were applied to the corrosion pits taken from an in-line inspection of the gas transmission pipeline. Basic rules of interaction of pipe wall metal losses are expressed in terms of longitudinal and circumferential spacing of the features in the colony. The effect of interactions of the detected anomalies on the tube residual strength evaluated according to the Det Norske Veritas Recommended practice was investigated in the current study. In the presented case, groups of closely-spaced defects behaved similarly as individual flaws with regard to their influence on burst pressure and pipeline failure probability.
Magdalena Młynarczyk, Anna Bogdan, Tomasz Jankowski
Thermal conditions in operating rooms are mainly dictated by the need to meet the safety/comfort requirements of the patient. However, the accuracy of performed surgical procedures depends on the surgeon and others members of medical team. Hence, their comfort sensation should be also factored in. The study sought to find out how thermal sensations of people working in surgical clothing can be modified through a local change in air velocity and temperature around the user. A series of tests was carried out with a thermal manikin to make an accurate assessment of the effectiveness of this type of equipment. The tests included changes of the ambient temperature, supply air temperature and air velocity. The operational efficiency was assessed on the basis of the equivalent temperature index (teq). Results show that the final result of teq was mostly determined by air velocity rather than the supply air temperature.
Marta Wiśniewska, Mirosław Szyłak-Szydłowski
The mechanical-biological waste treatment plants (MBTP), which include the municipal waste biogas plants, have an important role in sustainable urban development. Some plants are equipped with a sewage pre-treatment plant, which is then directed to the sewerage system and the treatment plant. Others, on the other hand, have only a non-drainage tank. The parameters of technological sewage (TS) or processing technology could reduce sewage contamination rates. In addition to the quality of sewage from waste treatment plants, the emission of odours is also an important problem, as evidenced by the results obtained over the sewage pumping station tank. The conducted statistical analysis shows a significant positive correlation between odour concentration (cod) and volatile organic compounds (VOCs). Analysing the individual compounds, a high positive correlation was also found—the strongest being between H2S, NH3 and VOCs. In the case of sewage compounds, the insignificant correlation between P total and other parameters was found. For the rest of the compounds, the highest positive correlation was found between COD and BOD and N-NO2 and N-NH3 as well as COD and N-NO2. The dilution of sewage is only an ad hoc solution to the problem. Further work should be aimed at reducing sewage pollution rates. The obtained results indicate large pollution of technological sewage and a high level of odour and odorants concentration. The novelty and scientific contribution presented in the paper are related to analyses of various factors on technological sewage parameters and odour and odorant emission from TS tank at biogas plant processing municipal waste, which may be an important source of knowledge on the management of TS, its disposal and minimisation of emitted compound emissions.
Łukasz Adamkiewicz , Katarzyna Maciejewska , Krzysztof Skotak , Michal Krzyzanowski , Artur Jerzy Badyda , Katarzyna Juda-Rezler , P. Dąbrowiecki
In this study Health Impact Assessment (HIA) methods were used to evaluate potential health benefits related to keeping air pollution levels in Poland under certain threshold concentrations. Impacts of daily mean particulate matter (PM)10 levels on hospital admissions due to cardiovascular and respiratory diseases were considered. Relative risk coefficients were adopted from WHO HRAPIE project. The analyses covered period from 2015 to 2017, and were limited to the heating season (1st and 4th quarter of the year), when the highest PM10 concentrations occur. The national total number of hospital admissions attributed to PM10 concentration exceeding WHO daily Air Quality Guideline value of 50 µg/m3 was calculated for each of the 46 air quality zones established in Poland. We found that the reduction of the attributable hospital admissions by 75% or 50% of that expected for the “best case scenario”, with no days with PM10 concentration exceeding 50 µg/m3 would require avoidance of exceedance by the daily mean PM10 concentration of 64 µg/m3 and 83 µg/m3, respectively. These concentrations were proposed as the information and alert thresholds, respectively. The alert thresholds were exceeded on 2 and 38 days per year in the least and the most polluted zones, respectively. Exceedances of the information thresholds occurred on 6 and 66 days in these zones.
Precipitation is a key variable in the hydrological cycle and essential input data in rainfall-runoff modeling. Rain gauge data are considered as one of the best data sources of precipitation but before further use, the data must be spatially interpolated. The process of interpolation is particularly challenging over mountainous areas due to complex orography and a usually sparse network of rain gauges. This paper investigates two deterministic interpolation methods (inverse distance weighting (IDW), and first-degree polynomial) and their impact on the outputs of semi-distributed rainfall-runoff modeling in a mountainous catchment. The performed analysis considers the aspect of interpolation grid size, which is often neglected in other than fully-distributed modeling. The impact of the inverse distance power (IDP) value in the IDW interpolation was also analyzed. It has been found that the best simulation results were obtained using a grid size smaller or equal to 750 m and the first-degree polynomial as an interpolation method. The results indicate that the IDP value in the IDW method has more impact on the simulation results than the grid size. Evaluation of the results was done using the Kling-Gupta efficiency (KGE), which is considered to be an alternative to the Nash-Sutcliffe efficiency (NSE). It was found that KGE generally tends to provide higher and less varied values than NSE which makes it less useful for the evaluation of the results.
Katarzyna Juda-Rezler , Elwira Zajusz-Zubek , Magdalena Marta Reizer , Katarzyna Maciejewska , Eliza Kurek , Ewa Bulska, Krzysztof Klejnowski
The analysis of bioavailability and potential risk to human health of trace and minor elements bound to atmospheric PM2.5 was carried out at an urban background site in Warsaw, Poland during a 40-day winter period. The samples were sequentially extracted into four different fractions: water soluble (F1), reducible (F2), oxidizable (F3) and residual (F4) for the chemical fractionation of 8 elements: As, Cd, K, Mn, Pb, Sb, Ti and Zn, and further analyzed using inductively coupled plasma mass spectrometry in each fraction. The average PM2.5 mass concentration of 31.81 μg/m3 (±19.73 μg/m3) was exceeding daily WHO air quality guideline, while concentrations rose up to 50–70 μg/m3 during episode days. Total concentrations of all analyzed elements were higher during the episode periods, with the highest increases for K, Pb (2 times) and Cd (1.7 times). All elements exhibited high bioavailability, as well as very high (K, Ti, Zn) and high (As, Cd, Mn, Pb, Sb) risk assessment code, with both features rising in episodic days up to 20% and more than 60%, respectively. Cancer risk for adults resulted from inhalation exposure to the most bioavailable fractions (F1 and F2) of human carcinogen As. It was higher than the precautionary criterion (1 · 10−6) and increased during the days with elevated PM2.5 levels.
Jan Bogacki , Piotr Marcinowski , Dominika Bury , Monika Krupa , Dominika Ścieżyńska , Prasanth Prabhu
There is a need for more effective methods of industrial wastewater treatment. Methods: Cosmetic wastewater was collected and subjected to H2O2/Fe3O4/Fe2O3/Fe0 and UV/H2O2/Fe3O4/Fe2O3/Fe0 process treatment. Results: Total organic carbon (TOC) was decreased from an initial 306.3 to 134.1 mg/L, 56.2% TOC removal, after 120 min of treatment for 1:1 H2O2/COD mass ratio and 500/500/1000 mg/L Fe3O4/Fe2O3/Fe0 catalyst doses. The application chromatographic analysis allowed for the detection and identification of pollutants present in the wastewater. Identified pollutants were removed during the treatment processes. Processes carried out at a pH greater than 3.0 were ineffective. The UV process was more effective than the lightless process. Conclusions: The applied processes are effective methods for wastewater treatment. Chromatographic results confirmed the effectiveness of the treatment method. The kinetics of the process were described by the modified second-order model. On the basis of ANOVA results, the hypothesis regarding the accuracy and reproducibility of the research was confirmed.
Michał Jakubczak , Ewa Karwowska , Anita Rozmysłowska-Wojciechowska , Mateusz Petrus , Jarosław Woźniak , Joanna Mitrzak , Agnieszka Jastrzębska
Point-of-use (POU) water treatment systems and devices play an essential role in limited access to sanitary safe water resources. The filtering materials applied in POU systems must effectively eliminate contaminants, be readily produced and stable, and avoid secondary contamination of the treated water. We report an innovative, 2D Ti3C2/Al2O3/Ag/Cu nanocomposite-modified filtration material with the application potential for POU water treatment. The material is characterized by improved filtration velocity relative to an unmodified reference material, effective elimination of microorganisms, and self-disinfecting potential, which afforded the collection of 99.6% of bacteria in the filter. The effect was obtained with nanocomposite levels as low as 1%. Surface oxidation of the modified material increased its antimicrobial efficiency. No secondary release of the nanocomposites into the filtrate was observed and confirmed the stability of the material and its suitability for practical application in water treatment.
Łukasz Szarek, Łukasz Krysiak
Owing to the increasing popularity of the thermal treatment of municipal sewage sludge (TTMSS) in Poland, constant growth in the quantity of ash generated within this process has been recorded. Due to their properties, it is difficult to utilize this type of ash within the concrete production technology. One of the methods of waste utilization is to add it to hardening slurries, used in, among others, cutoff walls. The slurry operating conditions (contact with groundwater) and elevated heavy metal content in ash raise justified concerns in terms of environmental safety of the aforementioned methods. In the study, the release of heavy metals from a matrix, namely, the hardened slurry has been examined. The so-called “batch test” dynamic leachability testing method was applied for this purpose. A high level of heavy metal immobilization in the slurry was achieved. The obtained results indicate an environmentally safe possibility of using TTMSS ash in hardening slurries in cut-off walls.
Łukasz Adamkiewicz , Maciej Kryza , Dominika Mucha , Małgorzata Werner , Anna Gayer , Anetta Drzeniecka-Osiadacz , Tymoteusz Sawiński
Emissions from the household sector are the most significant source of air pollution in Poland, one of the most polluted countries in the EU. Estimated health impacts of the reduction of these emissions under three scenarios are presented. The EMEP4PL model and base year emission inventory were used to estimate average annual PM10 and PM2.5 concentrations with spatial resolution of 4 km × 4 km. The change in emissions under each of the scenarios was based on data from a survey on household boilers and insulation. Scenario 1 included replacement of all poor-quality coal-fired boilers with gas boilers; Scenario 2 included replacement of all poor-quality coal-fired boilers with low-emission boilers but still using solid fuels; and Scenario 3 included the thermal refurbishment of houses with the worst insulation. Impacts on the following health parameters were estimated: premature deaths (PD), Chronic Bronchitis (CB), Bronchitis in Children (BiC) and Work Days Lost (WDL). The concentration–response functions recommended by the WHO HRAPIE project were used. The analysis was conducted for two regions: Lower Silesia and Lodzkie province. The largest reduction of health impact was observed for Scenario 1. For Lower Silesia, the annual PD decreased by 1122 (34.3%), CB by 1516 (26.6%), BiC by 9602 (27.7%) and WDL by 481k (34.7%). For Lodzkie province, the largest impacts were estimated as decreases in PD by 1438 (29.9%), CB by 1502 (25.3%), BiC by 9880 (26.8%) and WDL by 669k (30.4%).
Edyta B. Hendiger , Marcin Padzik , Agnieszka Żochowska , Wanda Baltaza , Gabriela Olędzka , Diana Zyskowska , Julita Bluszcz , Sylwia Jarzynka , Lidia Chomicz , Marta Grodzik , Jacek Hendiger , José E. Piñero , Jarosław Grobelny , Katarzyna Ranoszek-Soliwoda , Jacob Lorenzo-Morales
Background Free-living amoebae of the genusAcanthamoebaare cosmopolitan, widely distributed protozoans that cause a severe, vision-threatening corneal infection known asAcanthamoebakeratitis (AK). The majority of the increasing number of AK cases are associated with contact lens use. Appropriate eye hygiene and effective contact lens disinfection are crucial in the prevention of AK because of the lack of effective therapies against it. Currently available multipurpose contact lens disinfection systems are not fully effective againstAcanthamoebatrophozoites and cysts. There is an urgent need to increase the disinfecting activity of these systems to prevent AK infections. Synthesized nanoparticles (NPs) have been recently studied and proposed as a new generation of anti-microbial agents. It is also known that some plant metabolites, including tannins, have anti-parasitic activity. The aim of this study was to evaluate the anti-amoebic activity and cytotoxicity of tannic acid-modified silver NPs (AgTANPs) conjugated with selected multipurpose contact lens solutions.MethodsThe anti-amoebic activities of pure contact lens care solutions, and NPs conjugated with contact lens care solutions, were examined in vitro by a colorimetric assay based on the oxido-reduction of alamarBlue. The cytotoxicity assays were performed using a fibroblast HS-5 (ATCC CRL-11882) cell line. The results were statistically analysed by ANOVA and Student-Newman-Keuls test usingP< 0.05 as the level of statistical significance.ResultsWe show that the NPs enhance the anti-Acanthamoebaactivities of the tested contact lens solutions without increasing their cytotoxicity profiles. The activities are enhanced within the minimal disinfection time recommended by the manufacturers.ConclusionsThe conjugation of the selected contact lens solutions with AgTANPs might be a novel and promising approach for the prevention of AK infections among contact lens users.
Jerzy Sowa , Maciej Mijakowski
Humidity-sensitive, demand-controlled ventilation systems have been in use for many years in regions with oceanic climates. Some attempts have been made to apply this technology in Poland, which has a continental climate. This article evaluates the performance and energy consumption of such a system when applied in an eight-floor, multiunit, residential building, i.e., the virtual reference building described by the National Energy Conservation Agency (NAPE), Poland. Simulations using the computer program CONTAM were performed for the whole heating season based upon the climate in Warsaw. Besides passive stack ventilation, that served as a reference, two ventilation systems were studied: one standard and one “hybrid” system with additional roof fans. This study confirmed that the application of humidity-sensitive, demand-controlled ventilation in multiunit residential buildings in a continental climate (Dfb) led to significant energy savings (up to 11.64 kWh/m2 of primary energy). However, the operation of the system on higher floors was found to be ineffective. Ensuring consistent operation of the system on all floors required supplementary fans. The introduction of a hybrid mode reduced carbon dioxide concentrations by approximately 32% in the units located in the upper part of the building. The energetic effect in such cases depends strongly on the electricity source. In the case of the national energy grid, savings of primary energy would be relatively low, i.e., 1.07 kWh/m2, but in the case of locally produced renewable energy, the energy savings would be equal to 5.18 kWh/m2.
Marta Wiśniewska , Andrzej Kulig , Krystyna Lelicińska-Serafin
Municipal waste biogas plants are an important element of waste treatment and energy policy. In this study, odorant concentrations and emissions were measured together with the air temperature (T) and relative humidity (RH) to confirm the hypothesis that the microclimatic conditions have an important impact on the level of odorant emission at municipal waste biogas plants. A simple correlation analysis was made to evaluate the strength and the direction of the relationship between the odorant concentration and emission and air temperature and relative humidity. The mean volatile organic compound (VOC) and NH3 concentrations vary depending on the stage of the technological line of the analysed municipal waste biogas plants and are in the following ranges, respectively: 0–38.64 ppm and 0–100 ppm. The odorant concentrations and emissions correlated statistically significantly with T primarily influences VOC concentrations and emissions while RH mainly affects NH3 concentrations and emissions. The strongest correlations were noted for the fermentation preparation section and for emissions from roof ventilators depending on the analysed plant. The smallest influence of microclimatic factors was observed at the beginning of the technological line—in the waste storage section and mechanical treatment hall. This is due to the greater impact of the type and quality of waste delivered the plants. The analysis of correlation between individual odorants showed significant relationships between VOCs and NH3 for most stages of the technological line of both biogas plants. In the case of technological sewage pumping stations, a significant relationship was also observed between VOCs and H2S. The obtained results may be helpful in preparing strategies to reduce the odours from waste treatment plants.
Beata Karolinczak , Rafał Miłaszewski , Wojciech Dąbrowski
Analysis of the current knowledge has revealed the lack of a method for increasing the cost-effectiveness of wastewater and septage treatment in plants overloaded by contamination. This was the premise for undertaking research on the process of septage pre-treatment in a subsurface vertical flow constructed wetland (SS-VF) prior to its input into the biological section of a municipal treatment plant. In previous research the authors have indicated that this allows for a significant reduction in the value of pollution indicators. The objective of this paper is to assess the cost-effectiveness of this process by means of an optimization model. The decision variable was the coefficient of septage stream distribution into the quantity directed to the SS-VF bed in relation to its total quantity. The optimization criterion was the minimization of the expected annual cost of wastewater and septage treatment. Verification of the model has shown that it is reasonable to subject all septage to the pre-treatment in a SS-VF bed for small wastewater treatment plant (WWTPs) located in rural areas. The bigger the septage pollution load is, the greater the reduction in the treatment costs. The proposed solution is less cost-effective in urban areas, where the construction of a SS-VF bed requires land purchase and additional costs of its adjustment. Optimization results largely depend on the cost function, so it is important to build it on reliable local data.
Artur Jerzy Badyda , Piotr Krawczyk , Jan S. Bihałowicz , Karolina Bralewska , W. Rogula-Kozłowska , G Majewski , Przemysław Oberbek , Andrzej Marciniak , Mariusz Rogulski
The study attempts to compare the total annual emissions of selected air pollutants emitted during occasional grilling and the emission of the same pollutants from small domestic heating installations. For this purpose, in the absence of any data on the emission of pollutants during grilling processes, tests were carried out consisting of measuring the concentration of air pollutants in exhaust streams from two types of grills (solid fuel grill powered by charcoal briquette and gas grill powered by liquid propane), using popularly prepared dishes (previously marinated meat and raw, seasoned mixed vegetables). The concentrations of PM2.5, CH4, CO, CO2, H2O, NH3, N2O, NO, NO2, SO2 were measured in the exhaust stream from both grills using a particulate matter (PM) measuring device and a portable spectrometer, separately while grilling the same portions of meat and vegetables. Then, considering the available data on Poles’ barbecue habits, the emissions that are released into the air during occasional grilling were estimated. The calculated emissions were compared with the data on emissions from domestic heating installations used in Poland. It has been shown that during grilling, as much as 2.30, 92.07, 4.11, 3.83, 2.96, and 9.81 Gg of PM2.5, CO, NOx, SO2, NH3, and CH4 may be released into the atmosphere in Poland, respectively. In the case of PM, the amount of the pollutant emitted to the air is over 100 times lower than the emissions caused by the operation of small heating installations. In the case of other pollutants, the differences are smaller. Nevertheless, emissions from grills should not be underestimated as, in certain periods of the year, these sources may be responsible for not meeting the air quality standards in selected areas of the country, and thus the excessive exposure of people to pollutants resulting in negative health consequences. Therefore, attention was paid to the legitimacy of abandoning the use of charcoal and charcoal briquette grills and replacing them with gas-powered grills or electric ones, not only due to the health benefits of food and lower human exposure, but also by the reason of ecological values.
Jerzy Kwiatkowski , Joanna Rucińska
The need to achieve energy consumption and greenhouse gas emission decreases within the building sector requires the implementation of a supportive legal framework. To fulfil this requirement, a building certification system must be developed that is easily understandable for end users. In Poland, assessments of the energy performance of buildings are based on primary energy indicator verification. However, this parameter is difficult to understand for building owners or for tenants. Therefore, in this study, energy efficiency class limits and a heating indicator for energy needs indicator have been estimated for multi-family buildings in Poland. To achieve this purpose, a reference building was used and 180 calculation variants were developed, which considered the following variables: 3 types of climate data, 4 values of building shape ratios, 3 types of ventilation, 3 thermal transmittance standards and 3 windows area ratios to the external wall. The results showed that the greatest influences on the need for energy used for heating were the type of ventilation used and the local climate. This study shows that the methodology used is adequate for energy efficiency class limits estimations involving multi-family buildings in Poland.
M. Diaz, Grzegorz Igor Sinicyn, Maria Grodzka-Łukaszewska
The objective of the present paper is to develop a methodology that could allow the representation of the analytical hyporheic flux equation model (AHF) in a numerical model done in MODFLOW. Therefore, the scope of the research is to show the viability of the methodology suggested in a real case (Biebrza river, Poland, Europe). Considering that the model requires extensive manipulation in the creation of the packages, a test phase through the seepage package of MODFLOW is carried out with the aim of representing the river package of MODFLOW. FloPy is the tool chosen to develop this implementation due to the versatility of manipulating the packages available in MODFLOW through coding. The obtained results showed a correct implementation of the AHF model using the example of the Biebrza River. The results obtained will enable a better understanding regarding the modelling of the interaction between the river and the aquifer, considering streams with specific geometries where the depth is dimensionally higher than the width.
This paper investigates the influence of a fiber optic cable inserted into a straight steel pipeline on pressure oscillations occurring during the rapid water hammer phenomenon. In order to numerically simulate water hammer in the pipeline with an inserted cable, a one-dimensional model with variable pressure wave speeds was used. The required smoothing of the pressure wave was obtained by introducing a diffusion coefficient into the momentum equation. Transient equations were solved using a modified finite-element method. The numerical model was calibrated with the dissipation coefficient based on the results of our own experimental tests. In the experimental study, four different types of cables and three values of initial flow rates have been considered. The obtained values of the calibrated dissipation coefficient are directly proportional to the initial water flow velocity. The results demonstrate that this approach allows one to reproduce the damping of pressure oscillations accurately and to obtain satisfactory results compared to experimental data for a given range of volumetric flow rates.
Anna Rolewicz-Kalińska , Krystyna Lelicińska-Serafin , Piotr Manczarski
The analysis of biofiltration efficiency was performed with parallel VOC, H2S and NH3 removal using pilot two-stage biofilters including conventional biofiltration and purification on a membrane filter. The scope of the research was to determine the relationship between the technological parameters of the tested device (two beds and two membranes) and gases removal efficiency. Research was carried out in a semi-technical scale in three industrial plants: mechanical-biological municipal waste treatment (MBT), food industry (FI) and wastewater treatment (WWTP) plants. Experimental results indicate the efficiency removal of VOCs from 89% (WWTP) to 98% (FI), NH3 from 88% (WWTP) to 100% (MBT) and H2S from 93% (WWTP) to 100% (MBT). Biofilter with stumpwood chips-bark-compost bed, fortified with the more porous membrane was the most effective, allowing VOC, NH3 and H2S removal with an average efficiency of 99% for NH3 and H2S and 97% for VOCs. The application of membrane fabrics as the second stage of purification allows high efficiency simultaneous removal of VOCs, NH3 and H2S. Unlike two-stage purification, conventional biofiltration is effective at removing individual impurities from process gases. The results of this study indicate a high potential for practical application.
Piotr Marcinowski, Dominika Bury, Monika Krupa, Dominika Ścieżyńska, Prasanth Prabhu, Jan Bogacki
Wastewater from a cosmetic factory, with an initial total organic carbon (TOC) of 146.4 mg/L, was treated with Fe2O3/Fe0/H2O2, Fe3O4/Fe0/H2O2, light/Fe2O3/Fe0/H2O2, and light/Fe3O4/Fe0/H2O2 processes. The light-supported processes were more effective than the lightless processes. The fastest TOC removal was observed during the first 15 min of the process. Out of the four tested kinetic models, the best fit was obtained for the modified second-order reaction with respect to the TOC value. The best treatment efficiency was obtained for the light/Fe3O4/Fe0/H2O2 process with 250/750 mg/L Fe3O4/Fe0 reagent doses, a 1:1 hydrogen peroxide to Chemical Oxygen Demand (H2O2/COD) mass ratio, and a 120 min process time. These conditions allowed 75.7% TOC removal to a final TOC of 35.52 mg/L and 90.5% total nitrogen removal to a final content of 4.9 mg/L. The five-day Biochemical Oxygen Demand to Chemical Oxygen Demand (BOD5/COD) ratio was increased slightly from 0.124 to 0.161. Application of Head Space Solid-Phase Microextraction Gas Chromatography Mass Spectrometry (HS-SPME-GC-MS) analysis allows for the detection and identification of 23 compounds contained in the raw wastewater. The identified compounds were eliminated during the applied process. The HS-SPME-GC-MS results confirmed the high efficiency of the treatment processes.
Anita Rozmysłowska-Wojciechowska , Ewa Karwowska , Michał Gloc , Jarosław Woźniak , Mateusz Petrus , Bartłomiej Przybyszewski , Tomasz Wojciechowski , Agnieszka Jastrzębska
A recent discovery of the unique biological properties of two-dimensional transition metal carbides (MXenes) resulted in intensive research on their application in various biotechnological areas, including polymeric nanocomposite systems. However, the true potential of MXene as an additive to bioactive natural porous composite structures has yet to be fully explored. Here, we report that the addition of 2D Ti3C2Tx MXene by reducing the porosity of the chitosan-hyaluronate matrix nanocomposite structures, stabilized by vitamin C, maintains their desired antibacterial properties. This was confirmed by micro computed tomography (micro-CT) visualization which enables insight into the porous structure of nanocomposites. It was also found that given large porosity of the nanocomposite a small amount of MXene (1–5 wt.%) was effective against gram-negative Escherichia coli, gram-positive Staphylococcus aureus, and Bacillus sp. bacteria in a hydrogel system. Such an approach unequivocally advances the future design approaches of modern wound healing dressing materials with the addition of MXenes.
Edwin Koźniewski, Karolina Banaszak
In this paper, we present a new approach for the analysis of the dependence of construction costs on the geometric shape of a building. Instead of difficult or even impossible-to-establish uniform prices and costs, we propose a cost analysis concerning the amount of materials needed for construction. We show that the basic parameters are the base area of the building (plan), assumed in the study as the building area, and the area of the external walls of the building. The amount of consumption of most materials is proportional to the base area and the area of the external walls. The materials required for construction consume large amounts of energy during their manufacture. Therefore, shape optimization is not only economically significant for the investor but is also important in terms of the energy consumption, i.e., embodied energy. We propose a set of indicators to help a designer optimize the shape of the building at the initial design stage.
An experimental evaluation of an autocascade refrigeration (ACR) system was carried out. A zeotropic mixture of isobutane and CO2 was employed as a working fluid in an autocascade refrigeration (ACR) system. An experimental system was designed and built to study the influence of the recuperative heat exchanger (RHX) and openings of the throttle valves on the system performance. The use of RHX facilitated the condensation process and improved the cycle characteristics. The working mass concentration of CO2 was higher, as it was closer to the nominal concentration and the discharge pressure was lower by 19% to even 39% when the RHX was employed in the system. An increase of up to 20% in the coefficient of performance (COP) was observed. Furthermore, the effects of the openings of the throttle valves on the system characteristics were studied. The change in the openings of the expansion valves affected the mass flows and the working mixture composition. The working CO2 mass fraction increased with higher openings of the evaporator throttle. The subcooling degree of liquid CO2-rich refrigerant increased with higher openings of the expansion valve under the phase separator. The results of the present work should be helpful for design and optimization of autocascade systems working with natural and synthetic refrigerants.
Andrzej J. Osiadacz , Niccolo Isoli
The main goal of this paper is to prove that bi-objective optimization of high-pressure gas networks ensures grater system efficiency than scalar optimization. The proposed algorithm searches for a trade-off between minimization of the running costs of compressors and maximization of gas networks capacity (security of gas supply to customers). The bi-criteria algorithm was developed using a gradient projection method to solve the nonlinear constrained optimization problem, and a hierarchical vector optimization method. To prove the correctness of the algorithm, three existing networks have been solved. A comparison between the scalar optimization and bi-criteria optimization results confirmed the advantages of the bi-criteria optimization approach.
Marta Wiśniewska , Andrzej Kulig , Krystyna Lelicińska-Serafin
Biogas plants processing municipal waste are very important investments from the point of view of waste management and also the sustainable development of urban infrastructures. They may also have a potentially negative impact on the environment in the form of odour emission. Olfactometry is the main method for odour impact assessment. Field olfactometry allows for performing a wide range of tests, the results of which are practically instantaneous. The purpose of this work is to provide a tool for assessing the odour impacts of municipal management facilities, including biogas plants processing municipal waste and evaluating the correctness of processes carried out in these plants, namely the method of field olfactometry. In order to compare obtained olfactometric results with the concentration of chemical compounds, chromatographic tests were also carried out using the Photovac Voyager portable chromatograph (hydrogen sulphide – H2S and dimethyl sulphide – (CH3)2S. The results of the odour concentration tests are in line with the results of odorant concentration tests and indicate that cod is strongly related to the concentration of hydrogen sulphide. Thanks to this method, it is possible to find a relationship between odour nuisance, technological processes used in the plant and the type of treated waste.
An increasing number of municipal sewage treatment plants in Poland, desirable from an environmentalperspective, raises the problem of managing the growing volume of sewage sludge. The thermal treatment ofmunicipal sewage sludge (TTMSS) method, by greatly reducing the waste volume, increases the heavy metalconcentration in fly ash (primary, end product of the treatment process), which may constitute a risk factor whenattempting to utilize them economically. The research paper concentrates on determining the TTMSS fly ash heavymetal leaching level. For this purpose, ash samples were subjected to leaching with the batch and percolation tests,and the heavy metal content in eluates was determined by the FAAS method. The obtained results served as a base to determine the level of heavy metal immobilization in the ash, the element release mechanism (percolation test),and the impact of the L/S (liquid to solid) ratio and pH on the heavy metal leaching intensity (percolation test).The conducted research indicated high immobilization of heavy metals in TTMSS fly ash, regardless of the appliedstudy method, which corresponds to the results of other researchers. Lead was the most intensively eluted metal.
Mariusz Rogulski , Artur Jerzy Badyda
This article presents a long-term evaluation of low-cost particulate matter (PM) sensors in a field measurements campaign. Evaluation was performed in two phases. During the first five months of the campaign, two PM sensors were simultaneously compared with the results from the reference air quality monitoring station in various atmospheric conditions—from the days with freezing cold (minimum temperature below −10 °C) and high relative humidity (up to 95%) to the days with the maximum temperature above 30 °C and low relative humidity (at the level of 25%). Based on the PM10 measurements, the correlation coefficients for both devices in relation to the reference station were determined (r = 0.91 and r = 0.94, respectively), as well as the impact of temperature and relative humidity on measurements from the low-cost sensors in relation to the reference values. The correction function was formulated based on this large set of low-cost PM10 measurements and referential values. The effectiveness of the corrective function was verified during the second measurement campaign carried out in the city of Nowy Sącz (located in southern Poland) for the same five months in the following year. The absolute values of the long-term percentage errors obtained after adjustment were reduced to a maximum of about 20%, and the average percentage errors were usually around 10%.
Edward Majewski , Anna Wiktoria Komerska , Jerzy Kwiatkowski , Agata Malak-Rawlikowska , Adam Wąs , Piotr Sulewski , Marlena Goła , Kinga Pogodzinska , Jean-Loup Lecoeur , Barbara Tocco , Áron Török , Michele Donati , Gunnar Vittersø
Improving the eco-efficiency of food systems is one of the major global challenges faced by the modern world. Short food supply chains (SFSCs) are commonly regarded to be less harmful to the environment, among various reasons, due to their organizational distribution and thus the shortened physical distance between primary producers and final consumers. In this paper, we empirically test this hypothesis, by assessing and comparing the environmental impacts of short and long food supply chains. Based on the Life Cycle Assessment (LCA) approach, we calculate eco-efficiency indicators for nine types of food distribution chains. The analysis is performed on a sample of 428 short and long food supply chains from six European countries. Our results indicate that, on average, long food supply chains may generate less negative environmental impacts than short chains (in terms of fossil fuel energy consumption, pollution, and GHG emissions) per kg of a given product. The values of eco-efficiency indicators display a large variability across analyzed chains, and especially across different types of SFSCs. The analysis shows that the environmental impacts of the food distribution process are not only determined by the geographical distance between producer and consumer, but depend on numerous factors, including the supply chain infrastructure.
Ryszard Zwierzchowski , Marcin Wołowicz
The paper contains a simplified energy and exergy analysis of pumps and pipelines system integrated with Thermal Energy Storage (TES). The analysis was performed for a combined heat and power plant (CHP) supplying heat to the District Heating System (DHS). The energy and exergy efficiency for the Block Part of the Siekierki CHP Plant in Warsaw was estimated. CHP Plant Siekierki is the largest CHP plant in Poland and the second largest in Europe. The energy and exergy analysis was executed for the three different values of ambient temperature. It is according to operation of the plant in different seasons: winter season (the lowest ambient temperature Tex = −20 °C, i.e., design point conditions), the intermediate season (average ambient temperature Tex = 1 °C), and summer (average ambient temperature Tex = 15 °C). The presented results of the analysis make it possible to identify the places of the greatest exergy destruction in the pumps and pipelines system with TES, and thus give the opportunity to take necessary improvement actions. Detailed results of the energy-exergy analysis show that both the energy consumption and the rate of exergy destruction in relation to the operation of the pumps and pipelines system of the CHP plant with TES for the tank charging and discharging processes are low.
Grzegorz Wierzbicki , Mateusz Grygoruk , Maria Grodzka-Łukaszewska , Piotr Bartold , Tomasz Okruszko
The advances and retreats of ice sheets during Pleistocene significantly changed high- and mid-latitude landscapes and hydrological systems, albeit differently, in North America and Europe. On the southern margin of the Last Glacial Maximum (LGM) in the Baltic Sea basin, a specific type of valley has developed between glacial margins and upland or mountain slopes. We studied new geological data (boreholes, electrical resistivity imaging (ERI) from this geomorphic setting in Northeast Poland to understand: (1) how the landscape and river network evolved to eventually produce peat mires during the Holocene, and (2) the nature of groundwater recharge to fens in the upper Biebrza Valley. We present the results on a geological cross-section with hydrogeological interpretation. We also discuss regional geomorphology. In addition, we present the LGM extent derived from a spatial distribution of Vistulian (Weichselian) terminal moraines. These end moraines are also interpreted as Saalian kames. Thus, we additionally present another method of LGM extent delineation from a physicogeographical division. We link the steep slopes of the studied valley walls (kame terrace fronts) with thermokarst erosion in the periglacial zone. We then document the hydrogeological window (DISCONTINUITY in the till layer over the confined aquifer), which enables the outflow of groundwater into the peat bog. Although minerotrophic fen mire development in the study area is likely to be sustained in the near future through sufficient groundwater supply, the projected capture of the Biebrza River by the Neman River will not allow for sustaining peatland development.
Anna Rolewicz-Kalińska , Krystyna Lelicińska-Serafin , Piotr Manczarski
Densely populated areas with large incoming populations have difficulty achieving high separate collection rates of municipal solid waste. The manuscript analyzes the link between biowaste collection and circular economy requirements as a fulfilment of the recycling rates and using biogas as a sustainable energy source. Three biowaste collection scenarios and three technical scenarios for its treatment are considered. The first scenario assumes only composting for biowaste treatment, the next includes also anaerobic digestion. In the years 2020–2050, the separate biowaste collection level will increase, depending on the scenario, from 26.9 kg/inh. up to 148.1kg/inh. By 2030, the quantity of biogas generated from biowaste can grow to almost 9 million m3/year, enabling the production of renewable energy at annual levels of almost 17 GWh and 69 TJ. Using the third scenario, the quantity of biogas generated grows more than twice (in 2035). If the capture rate of biowaste increases from 15% to 20% and then to 25%, the quantity of biogas generated grows by, respectively, 65% and more than 100%. Unfortunately, none of the scenarios enables the required municipal solid waste recycling rates in 2030 (60%) and 2035 (65%), which demonstrates the significant need to develop more effective separate collection systems, including biowaste. Methodology applied in the paper can be used for other cities and regions trying to meet circular economy demands.
Andrzej Białowiec , Jakub Pulka , Marzena Styczyńska , Jacek A. Koziel , Joanna Kalka , Marcelina Jureczko , Ewa Felis , Piotr Manczarski
Improved technologies are needed for sustainable management of sewage sludge (SS). The torrefaction (also known as biomass “roasting”) is considered a pretreatment of SS before use in agriculture. However, it is not known whether the torrefaction has the potential to decrease heavy metals’ (HMs) leachability and the SS toxicity. Thus, the aim of the study was to evaluate the influences of the SS torrefaction parameters (temperature and process time) on HM contents in biochar, HM leachability, and biochar toxicity, and compare them with raw SS. The experiments were designed in 18 combinations (six temperatures, 200, 220, 240, 260, 280, and 300 °C; and three process times—20, 40, 60 min). Standard tests were used to determine HMs content, leachability, and toxicity. Results indicated that the torrefaction did not increase (p < 0.05) the HM content in comparison to the raw SS. The leachability of Zn, Ni, Cu, Cr, and Mn from SS biochars was similar to raw SS. However, the degree of leachability varied significantly (p < 0.05) from as low as 0.1% for Cu to high as 16.7% for Cd. The leachability of Cd (<16.7%) and Pb (<11.9%) from biochars was higher than from raw SS (<6.1% and <2.4%, respectively). The leachability of Cd from SS biochar, in five torrefaction combinations, was higher than the threshold value for hazardous waste. It is recommended that site-specific decisions are made for torrefaction of SS with respect to its HM content, as the resulting biochar could be considered as hazardous waste, depending on the feedstock. Moreover, the biochar produced under the whole range of temperatures during 20 min retention time significantly (p < 0.05) increased the Daphnia magna Straus mobility inhibition by up to 100% in comparison to the biochar obtained during 40 and 60 min torrefaction. Taking into account the increased leachability of specific HMs and D. magna Straus mobility inhibition, biochar should be considered a potentially hazardous material. Future research should focus on biochar dosage as a fertilizer in relation to its toxicity. Additional research is warranted to focus on the optimization of SS torrefaction process parameters affecting the toxicity.
Andrzej J. Osiadacz , Maciej Chaczykowski
The role of modeling and simulation in development and operational planning of gas distribution networks is crucially important for system designers and operators, since it allows to get a detailed knowledge of the hydraulic properties of the network. The challenges in simulation of gas distribution networks are usually that of computational efficiency of the methods due to large dimensionality of the simulated networks, though it can also be related to flexible incorporation of the peripheral equipment (e.g., valves, compressors, pressure, and flow regulators) into the network model. Today, however, new challenges emerge as a consequence of market changes facing the gas industry in a multienergy system environment. These changes are expected to bring about significant fluctuations and uncertainty in distributed gas supply and demand as a consequence of increased gas-to-power activities, and a number of decentralized entry points, where deliveries of both liquefied natural gas (LNG) and renewable gases, such as hydrogen and synthetic methane, can be achieved. In this article, technical challenges related to problems with maintaining a stable overall gas distribution system with growing diversification of gas quality combined with gas trading activities (nominations and allocations) in units of energy rather than volume are addressed. Models and selected methods of steady state and transient analysis of gas networks relevant to the ongoing discussion in the field of multienergy systems are considered. The simulation problems of a real large-scale gas distribution network are presented and discussed.
Anna Gnida, Monika Żubrowska-Sudoł, Katarzyna Sytek-Szmeichel, Jolanta Podedworna, Joanna Surmacz-Górska, Dorota Marciocha
Background The study aimed to evaluate the influence of the duration times of anaerobic phases on the bacterial biocenosis characterisation while denitrifying dephosphatation in the Integrated Fixed-Film Activated Sludge – Moving-Bed Sequencing Batch Biofilm Reactor (IFAS-MBSBBR). The experiment was conducted in a laboratory model. The study consisted of four series, which differed in terms of the ratio of the anaerobic phases. duration concerning the overall reaction time in the cycle. The anaerobic phases covered from 18 to 30% of the whole cycle duration. During the reactor performance that took 9 months, the influent and effluent were monitored by analysis of COD, TKN, NH4-N, NO2-N, NO3-N, TP, PO4-P, pH, alkalinity and the phosphorus uptake batch tests. Characterisation of the activated sludge and the biofilm biocenosis was based on fluorescent in situ hybridisation (identification of PAO and GAO) and the denaturing gradient gel electrophoresis patterns. Results The organic compounds removal was high (more than 95.7%) independently of cycle configuration. The best efficiency for nitrogen (91.1%) and phosphorus (98.8%) removal was achieved for the 30% share of the anaerobic phases in the reaction time. Denitrifying PAO (DPAO) covered more than 90% of PAO in the biofilm and usually around 70% of PAO in the activated sludge. A substantial part of the polyphosphate accumulating organisms (PAO) community were Actinobacteria. The denitrifying dephosphatation activity was performed mainly by Accumulibacter phosphatis. Conclusions High nutrient removal efficiencies may be obtained in IFAS-MBSBBR using the denitrifying dephosphatation process. It was found that the length of anaerobic phases influenced denitrification and the biological phosphorus removal. The extension of the anaerobic phases duration time in the reaction time caused an increase in the percentage share of denitrifying PAO (DPAO) in PAO. The biocenosis of the biofilm and the activated sludge reveal different species patterns and domination of the EBPR community.
Radosław Żyłka , Wojciech Dąbrowski , Paweł Malinowski , Beata Karolinczak
The intensification of biological wastewater treatment requires the high usage of electric energy, mainly for aeration processes. Publications on energy consumption have been mostly related to municipal wastewater treatment plants (WWTPs). The aim of the research was to elaborate on models for the estimation of energy consumption during dairy WWTP operation. These models can be used for the optimization of electric energy consumption. The research was conducted in a dairy WWTP, operating with dissolved air flotation (DAF) and an activated sludge system. Energy consumption was measured with the help of three-phase network parameter transducers and a supervisory control and data acquisition (SCADA) system. The obtained models provided accurate predictions of DAF, biological treatment, and the overall WWTP energy consumption using chemical oxygen demand (COD), sewage flow, and air temperature. Using the energy consumption of the biological treatment as an independent variable, as well as air temperature, it is possible to estimate the variability of the total electric energy consumption. During the summer period, an increase in the organic load (expressed as COD) discharged into the biological treatment causes higher electric energy consumption in the whole dairy WWTP. Hence, it is recommended to increase the efficiency of the removal of organic pollutants in the DAF process. An application for the estimation of energy consumption was created.
Almost all inhabitants of developed countries spend the majority of their time in buildings. Therefore, high expectations regarding the environment of the rooms they occupy should not surprise anyone. These expectations are addressed basically by architects and HVAC engineers. Surprisingly, more or less consciously, they try to reproduce the microclimate of the African savanna.
The investigation focused on the non-migrating mid-channel bars that emerged in the river channel as a consequence of river engineering. A reach of around 280 km of Middle Vistula River (Poland) was taken into account as the study site. The most vivid examples of the river engineering works potentially influencing the river channel are the ferry crossings. Along the Middle Vistula River reach, there are 17 ferry crossings that were constructed from 1970s to 1990s. A cartographic analysis was carried out to determine the influence of the ferry crossing construction over the river channel. It was performed on the basis of aerial photographs (traditional aerial photography and UAV photography). In 3 out of 17 potential localizations, the emergence of large non-migrating mid-channel bars was observed. A study of cartographic materials (from 1950s to 2000s) allowed determination of the dynamics of those bars, including time of emergence and the changes of their size.
Marta Wiśniewska, Andrzej Kulig, Krystyna Lelicińska-Serafin
Municipal waste treatment is inherently associated with odour emissions. The compounds characteristic of the processes used for this purpose, and at the same time causing a negative olfactory sensation, are organic and inorganic sulphur and nitrogen compounds. The tests were carried out at the waste management plant, which in the biological part, uses the methane fermentation process and is also equipped with an installation for the collection, treatment, and energetic use of biogas. The tests include measurements of the four odorant concentrations and emissions, i.e., volatile organic compounds (VOCs), ammonia (NH3), hydrogen sulphide (H2S), and methanethiol (CH3SH). Measurements were made using a MultiRae Pro portable gas detector sensor. The tests were carried out in ten series for twenty measurement points in each series. The results show a significant impact of technological processes on odorant emissions. The types of waste going to the plant are also important in shaping this emission. On the one hand, it relates to the waste collection system and, on the other hand, the season of year. In addition, it has been proved that the detector used during the research is a valuable tool enabling the control of technological processes in municipal waste processing plants.
Tomasz Owczarek, Mariusz Rogulski, Piotr O. Czechowski
The aim of the work is to demonstrate the possibility of building models to correct the results of measurements of particulate matter PM10 concentrations obtained using low-cost devices. Such devices apply the optical method to values comparable with those obtained using the reference gravimetric method. An additional goal is to show that the results corrected in this way can be used to carry out the procedure for testing equivalence of these methods. The study used generalized regression models (GRMs) to construct corrective functions. The constructed models were assessed using the coefficients of determination and the methodology of calculating the measurement uncertainty of the device. Measurement data from the two tested devices and the reference method were used to estimate model parameters. The measurement data were collected on a daily basis from 1 February to 30 June 2018 in Nowy Sącz. Regression allowed building multiple models with various functional forms and very promising statistical properties as well as good ability to describe the variability of reference measurements. These models also had very low values of measurement uncertainty. Of all the models constructed, a linear model using the original PM10 concentrations from the tested devices, air humidity, and wind speed was chosen as the most accurate and simplest model. Apart from the coefficient of determination, expanded relative uncertainty served as the measure of quality of the obtained model. Its small value, much lower than 25%, indicates that after correcting the results it is possible to carry out the equivalence testing procedure for the low-cost devices and confirm the equivalence of the tested method with the reference method.
Katarzyna Anna Affek , Adam Muszyński , Monika Załęska-Radziwiłł , Nina Doskocz , Aleksandra Ziętkowska , Marcin Widomski
Treated wastewater may be a valuable source of water and/or nutrients for crop production and fish farming. Disinfection of treated wastewater should be performed to protect water resources against pathogenic and opportunistic microorganisms, as well as micropollutants contained in effluents. However, in the case of ozonation of treated wastewater, a large portion of contaminants do not undergo complete mineralization and can be transformed into by-products of unknown toxicity. The research performed in this study by culture-dependent and independent methods showed that the inactivation of bacteria in treated wastewater by ozonation does not take place effectively and may depend on the presence of other contaminants that may first react with the disinfectant. Some bacterial cells proved to be damaged by a disinfectant to the extent that they were unable to grow on nutrient media, but they were still viable and potentially posing a sanitary threat. Possible reasons for the disinfection failure were investigated and discussed. Ecotoxicity tests with algae Desmodesmus quadricauda, crustacean Daphnia magna, and bacteria Aliivibrio fischeri showed that by-products may be formed during ozonation of treated wastewater which is toxic to aquatic organisms. The toxicity class of treated wastewater may change from the completely non-toxic to very high hazard category, and there is a clear relationship between the time of ozonation and the increase in ecotoxicity.
Joanna Rucińska , Anna Wiktoria Komerska , Jerzy Kwiatkowski
The decarbonisation goal stated in the Energy Performance of Buildings Directive (EPBD) regarding the building sector will be achieved only if the whole building life-cycle is considered. To fulfil this requirement, a benchmark based on the life cycle assessment (LCA) must be integrated into the early planning phase of buildings by designers. The estimation of such indicators requires the development of a database of building assessments. In this study, an LCA of 11 office buildings in Poland was used to set average values that can be used as a benchmark. The LCA methodology based on the Building Research Establishment Environmental Assessment Method (BREEAM) certification was used. The analysis did not concentrate on one type of office building. The main objective was to investigate a possible range of total Global Warming Potential (GWP) index values normalized to the usable unit floor area. The importance of the GWP of individual life-cycle phases was also considered. The study shows that the used methodology is adequate for LCA benchmark estimation to set preliminary average values for office buildings in Poland.
Marek Nawalany , Grzegorz Igor Sinicyn , Maria Grodzka-Łukaszewska , Dorota Mirosław-Świątek
Modelling of water flow in the hyporheic zone and calculations of water exchange between groundwater and surface waters are important issues in modern environmental research. The article presents the Analytical Hyporheic Flux approach (AHF) permitting calculation of the amount of water exchange in the hyporheic zone, including vertical water seepage through the streambed and horizontal seepage through river banks. The outcome of the model, namely water fluxes, is compared with the corresponding results from the numerical model SEEP2D and simple Darcy-type model. The errors of the AHF model, in a range of 11–16%, depend on the aspect ratio of water depth to river width, and the direction of the river–aquifer water exchange, i.e., drainage or infiltration. The AHF model errors are significantly lower compared to the often-used model based on vertical water seepage through the streambed described by Darcy’s law.
Klaudia Weronika Pałaś, Jarosław Zawadzki
Deforestation is currently among the most critical ecological issues, which need to be addressed urgently. Hence, identification of effective environmental monitoring methods is of top priority, especially in locations where no precise ground-based data are available. Constant development of remote sensing technology provides an increasing number of tools needed for that purpose, based on extraction of information about Earth’s surface. One of the most advanced Earth Observation (EO) programs is Copernicus, established by European Space Agency (ESA). It incorporates a constellation of Sentinel satellites continuously delivering imagery, which can serve as input data for further environmental analyses. They can be performed in the Sentinel Application Platform (SNAP), the software also developed by ESA. The Sentinel-2 (S-2) mission was designed specifically for Earth’s surface observation. It acquires high-resolution data within visible and infrared range of electromagnetic spectrum (EMS), which has found applications in forest cover monitoring. In this paper, S-2 imagery was processed in SNAP software to determine its potential for deforestation observation on the example of 2017 tree logging in Białowieża Forest. For this purpose, images from October 2016 and 2018, covering the area of interest, were downloaded from the Copernicus Open Hub Platform. They then underwent pre-processing, involving atmospheric correction, resampling, and subset operations. As a part of environmental analysis, a set of chosen radiometric and biophysical indices was computed to preliminarily determine their usefulness for deforestation mapping. Index values were extracted from tree logging areas using pinpoints and region of interest (ROI) mask. The most effective indicators were the MERIS Terrestrial Chlorophyll Index (MTCI) and the Brightness Index (BI). The Normalized Difference Vegetation Index (NDVI), as well as the Ratio Vegetation Index (RVI), also displayed promising results. The results were visualized in Quantum GIS (QGIS) software, provided by the Open Source Geospatial Foundation (OSGeo).
Monika Żubrowska-Sudoł , Aleksandra Dzido , Agnieszka Garlicka , Piotr Krawczyk , Michał Stępień , Katarzyna Umiejewska , Justyna Walczak , Marcin Wołowicz , Katarzyna Sytek-Szmeichel
The study objective was to adjust the hydrodynamic disintegrator dedicated to sewage sludge pre-treatment (HDS) to work with agricultural substrate. This involved the development and implementation of a mathematical model of flow via the device’s domain. An innovative disintegrator (HAD—hydrodynamic disintegrator for agriculture) was designed, built, and tested based on the obtained results. The main improvements to the HDS include the implementation of shredding knives in order to overcome clogging by crushed substrate, and the application of ribs in the recirculation zone, contributing to the development of an additional structure damage zone. The challenge of this study was also to determine the operating parameters of the HDA that would provide for an increase in methane production with positive energy balance. The testing procedures, for which maize silage was selected, involved batch disintegration tests and biochemical methane potential tests. No clogging of rotor or spontaneous shutting off of the device, in other words, problems that had occurred in the HDS, were observed. The applied pre-treatment method permitted an increase in the methane potential of maize silage by 34.4%, 27.0%, and 21.6%, respectively for samples disintegrated at energy densities of 10 kJ/L, 20 kJ/L, and 35 kJ/L with net energy profit.
The work presents the results of short-term health effects assessment of particulate matter (PM) in Warsaw, the capital of Poland. The influence of three PM fractions, PM10 (particles of aerodynamic diameter < 10 μm), PM2.5 (particles of aerodynamic diameter < 2.5 μm), and PMc (coarse fraction of diameter between 2.5 and 10 μm), modeled by the CALMET/CALPUFF system, has been studied in the period of 2013–2014. Six population health endpoints; daily counts of all-cause (ALL), cardiovascular (CV), and respiratory (RS) death cases; and ALL, CV, and RS hospital admissions were investigated with the use of statistical time series analysis via nonparametric generalized additive model (GAM) approach. The results show that PM2.5 increases the relative risk (RR) of ALL premature deaths by 0.7% per 10 μg/m3, as well as of CV mortality by 0.9%. PM10 exposures reveal the largest influence on mortality in a 2-day lag: 0.3% for all causes and 0.4% for CV causes, while for RS causes only in the elderly group (above 65 years, 1.4%) and for males (2.1%). The risk of hospitalizations increases with elevated PMc levels by 2.5%, 2.1%, and 4.6% for ALL, CV, and RS hospital admissions, respectively. The results suggest that the research on PM impact on health should concentrate more on attempts to assign specific health outcomes to PM originating from different types of sources, characterized by different granulation, as well as physical and chemical properties of emitted particles.
Karol Michał Przeździecki , Jarosław Zawadzki
Estimation of soil moisture condition on a local or regional scale is one of the most important problems in vegetation conditions monitoring. One of the most suitable approach to do this over vegetated areas is the Land Surface Temperature – Vegetation Index (LST-VI) Triangle Method. This method estimates water content in soil which is available for plants in contrast to methods using satellite observations in the microwave band, and it is superior to pixel by pixel soil moisture methods using observations in the optical band which neglect statistical relationship between VI and LST controlling evapotranspiration on vegetated area. This study tested a methodological modification of the method based on assumption that evapotranspiration depends on the difference between the air temperature and the terrain surface temperature. The spatial distribution of Temperature-Vegetation Dryness Indices, which reflect soil moisture in the root zone was calculated for vast areas of Central Europe using the classic Triangle Method and its modified version. Both NDVI and EVI indices were used as input data in these calculations. The air temperature at 2 m height was taken from SYNOP reports, and the terrain surface temperature from MODIS data. In addition, Matlab scripts were written by the authors to allow convenient access to free SYNOP data. Our results indicate that proposed modification increases the accuracy of soil moisture estimation. This was confirmed by comparing classic and modified Temperature-Vegetation Dryness Indices values with rainfall data.
Monika Żubrowska-Sudoł , Justyna Walczak , Agnieszka Garlicka , Katarzyna Sytek-Szmeichel , Katarzyna Umiejewska
The objective of the study was to verify whether the method of determining the efficiency of sewage sludge disintegration, i.e. the disintegration degree (DD), can also be used to assess agro-waste disintegration. The following types of agro waste were tested: remains of fruits, sugar beet pulp and sugar beet pulp in the form of pellets. It was shown that DD as used for sewage sludge can also be a useful tool in assessing the disintegration efficiency of agro waste, although it requires the following modifications: (a) a methodology of chemical hydrolysis for each type of agro waste in order to determine the total amount of soluble COD (SCOD) that can be released from the sample and (b) possible changes in the SCOD value that may occur in the sample left in ambient conditions for a time period corresponding to the duration of the disintegration process. DD of agro waste determined according to the formula adopted for sewage sludge resulted in a considerable overestimation of the value in comparison to the formula proposed by the authors, i.e. DD determined for an energy density of 35 kJ L−1 was higher by 55.9 ± 21.5%, and for an energy density of 140 kJ L−1 it was higher by as much as 73.8 ± 28.1%. Taking into account the differences in the determined disintegration degree values that result from the methodology of conducting the chemical hydrolysis, it is recommended, in order to assess the efficiency of disintegration of agro waste, to use the efficiency of organic compound release.
Lech Gawuć, Maciej Krystian Jefimow, Karol Paweł Szymankiewicz, Magdalena Kuchcik, Anahita Sattari, Joanna Strużewska
Urban heat island (UHI) is one of the most distinctive characteristics of urban climate. The objective of this study is to apply a statistical modeling of the nocturnal atmospheric UHI based on the relationship between observed air temperature from ground stations and remotely sensed temperature of the urban surface. The goal of the approach is to limit input data for the developed modeling method in order to assure transferability of the methodology in different cities. Time series of surface temperature and normalized difference vegetation index are obtained from the MODIS instrument for a 10-year period (2008–2017). The air temperature is collected from the in-situ observational network of 21 stations. The studies are conducted for different locations with gradual changes in urbanization in order to assess the impact of urbanization on the relationship between simultaneous air and surface UHI. The urbanization is described by commonly available land cover metrics. Results showed that the proposed approach provides satisfactory AUHI modeling results for the locations with the least degree of urbanization. The best results are obtained with a simple linear regression model with the iterative procedure to minimize the mean absolute gross error (MAGE). The lowest MAGE for modeled UHI is 1.18 °C with 69% of the variance explained. The strongest linear relationship between simultaneous SUHI and AUHI is noted for those station pairs whose surroundings have the highest differences in urbanization, and the highest UHI intensities are observed. The strength of the SUHI/AUHI linear relationship decreases gradually with the increasing urbanization of the stations’ surroundings.
Agnieszka Garlicka, Monika Żubrowska-Sudoł
The main objective of the study was the verification whether conducting the hydrodynamic disintegration (HD) of thickened excess sludge (TES) before the anaerobic hydrolysis (AH) can cause an increase in the efficiency of the hydrolysis process, and therefore a reduction in its duration, or allow for complete omission of the stage before the anaerobic digestion (AD). For this purpose, the HD (conducted in five levels of energy density (EL): 140, 280, 420, 560 and 700 kJ/L) of TES was carried out, and then all sludges (before and after disintegration) were subjected to the AH. The obtained results confirmed that the process of HD can be an effective method of increasing the solubilisation and bioavailability of TES. In the process of HD, the maximum increase in ΔVFA (308–428 mg VFA/L), was reported when EL was increased from 140 to 280 kJ/L (the solubilisation degree increased from approximately 2 to 8%). The obtained results also showed that the ΔSTN and ΔSTP were related to solubilisation degree. The most intensive increase in the ΔSTN was determined for solubilisation degree in a range of 15–20%. In the case of ΔSTP, constant intensity of release of the compounds to the sludge liquid was observed. The obtained results also confirmed that conducting the process of AH of disintegrated TES proved to change the SCOD value when contrasted with the value of this indicator at the start of the experiment (before hydrolysis): (i) the EL equal to 140 and 280 kJ/L allowed for a higher SCOD value; (ii) at EL higher or equal to 560 kJ/L it caused a decrease in the SCOD value.
Joanna Rucińska, Adrian Trząski
This paper deals with the impact of the use of daylight on the overall energy demand for heating, cooling, and lighting in educational buildings. The energy performance of buildings is currently of the utmost importance as current European regulations, starting from 31st December 2020 impose that all new buildings must meet nearly zero-energy building requirements. This paper presents a study of the illuminance distribution in an educational room obtained from measurements and simulation results using two different models. One of the models, integrated with a thermal simulation software, was used to estimate the impact of daylight on the energy demand. The analysis included the use of various window types, lighting control system, reference point location, and daylight calculation model for a sample room in an educational building. Results of the analysis indicate that, due to the high share of lighting demand (reaching up to 78% of the primary energy balance), there is a need to take into account the efficiency of lighting systems during the design process to correctly determine the actual energy balance of a building, increase the quality of the design of lighting systems, as well as to select the optimal parameters of windows.
Agnieszka Garlicka, Monika Żubrowska-Sudoł, Katarzyna Umiejewska, Otton Roubinek, Jacek Palige, Andrzej Chmielewski
The main purpose of this study was the assessment of the possibility of increasing the production of biogas through the pre-treatment of thickened excess sludge (TES) by means of the hydrodynamic cavitation (HC) conducted at different levels of energy density (EL) i.e., 70, 140 and 210 kJ/L. The experiments were performed on a pilot scale, and a mixture of thickened primary sludge (TPS) and TES was used as digester feed. The results documented that an important parameter determining the possibility of obtaining an enhanced methane production is the value of energy input in the HC process. This parameter determines the changes occurring in sludge as a result of disintegration (i.e., sludge floc deagglomeration, lysis of cells, re-flocculation process and the related release of compounds susceptible to biodegradation from sludge flocs). The maximum increase in methane yield (MY) of 152% was obtained for EL = 140 kJ/L. In this case, HC mainly caused sludge floc deagglomeration. An increase in MY was also recorded when TES was subject to the disintegration process at EL = 210 kJ/L. However, it was 4.3 times lower than that observed for EL = 140 kJ/L. Pre-treatment of TES at EL = 70 kJ/L did not contribute to an increase in methane production.
B. Kubat , Marian Kwietniewski
In the study, the authors have attempted to develop a failure rate prediction model for a selected water supply network using linear regression, taking into account the simultaneous impacts of many factors on the failure rate; also, possible methods of failure rate visualization for the examined network were presented. In the regression model, the dependent variable is the unit failure frequency (fail/(km year)), whereas independent variables (explaining this frequency) are: pipe material, age and diameter, soil type (impermeable, permeable) and soil moisture content (dry, wet). Statistical analyses have shown that the failure rate of the examined water supply network is affected only by soil conditions. Spatial distribution of the failure number and frequency was visualized, paying special attention to the parts of the network where the spatial concentration of failures was the greatest.
Nina Doskocz , Monika Załęska-Radziwiłł , Katarzyna Anna Affek , Maria Lucyna Łebkowska
In the literature, there are few ecotoxicological data concerning the effects of nanoparticles on reducers, which are an important element of the food chain in aquatic ecosystems. The work aimed to evaluate the influence of two types of engineering nanoparticles: aluminum oxide (nano-Al2O3) and zirconium oxide (nano-ZrO2) on micro-organisms. In this work enzymatic assay (bioluminescence test) with Vibrio fischeri was performed as well as two growth tests: test with Pseudomonas putida and test microbial assay for toxic risk assessment with 10 species of bacteria and 1 species of fungi). In this study, the effect of the activity of nano-Al2O3 and nano-ZrO2 on micro-organisms as compared to their bulk counterparts. The obtained values of concentrations of EC50 and no observed effect concentrations showed a different sensitivity of the organisms to the examined compounds. According to the European Union criteria, nano-Al2O3 was very toxic to P. putida (EC50 = 0.5 mg/L), while nano- ZrO2 was harmful to Pichia anomala (EC50 = 89.80 mg/L) and P. putida (EC50 = 25.4 mg/L). Nanoparticles proved to be more toxic to tested micro-organisms than their bulk counterparts. This indicates that the nano-form of a given substance may pose a greater hazard for the environment than the same substance in the large form.
Katarzyna Juda-Rezler, Magdalena Reizer, Katarzyna Maciejewska, Barbara Błaszczak, Krzysztof Klejnowski
For the purposes of this work, a first in Poland, full-year collection of daily PM2.5 (particulate matter with aerodynamic diameter smaller than 2.5 μm) samples was chemically analyzed to determine the contents of elemental and organic carbon, water-soluble inorganic ions and 21 minor and trace elements in PM in an urban background site in Warsaw. Annual mean PM2.5 concentration reached 18.8 μg/m3, with the lowest levels in summer (11.5 μg/m3 on average) and the highest in winter (27.5 μg/m3), with several episodes reaching over 80 μg/m3. Strong seasonal differences were observed mainly for the contents of nitrate and secondary organic carbon (SOC), while sulphate showed the least variability. Secondary species constituted on average 45% of PM2.5 mass, suggesting large influence of regional and long-range transport of pollutants. Source apportionment with the use of positive matrix factorization (PMF) method, supported by the analysis of enrichment factors, led to identification of six main sources of PM2.5 origin: residential combustion (fresh & aged aerosol) (46% of PM2.5 mass), traffic exhaust (21%) and non-exhaust (10%) emissions, mineral dust/construction works (12%), high-temperature processes (8%) and steel processing (3%). Including primary organic carbon (POC) and SOC as two separate constituents helped to distinguish between the primary and secondary sources of the aerosol. The identification of sources was also supported by investigating their yearly and weekly profiles, as well as the correlation of PM constituents with meteorological conditions, which are one of the main drivers of heat generation activities. We found that the most distinctive markers of PM sources in Warsaw are SOC, Cl− and As for residential combustion, NH4+, Sb and POC for road transport, Ca and Mg for construction works and SO42− for long-range transport of PM.
Monika Załęska-Radziwiłł , Nina Doskocz , Katarzyna Anna Affek , Adam Muszyński
The study examined structural and functional changes in the microcosm, inhabited by representatives of all trophic levels of the aquatic food chain, in the presence of aluminum oxide nanoparticles and their bulk counterparts (100 mg/L). The 28 d experiment showed negative effects of nano-Al2O3 on aquatic ecosystems, as evidenced by reduced biodiversity of microbenthic and plankton organisms. Furthermore, exposure to nanoparticles contributed to the increase of the activity of antioxidative enzymes of benthos. Cytochemical analysis of Daphnia magna crustacean cells showed accumulation of nanoparticles on the surface of organisms and in their mitochondria, causing swelling of mitochondrial cristae, as well as disturbances of their system with a clear matrix in the centre of organelles. However, there were no significant changes in microcosms with bulk counterparts of nanoparticles, as well as no accumulation of aluminum oxide on the surface, nor in the mitochondria of D. magna, was detected.
Joanna Rotnicka, Maciej Dłużewski, Maciej Dąbski, Mirosław Rodzewicz, Wojciech Włodarski & Anna Zmarz
Recent developments in unmanned aerial vehicles (UAVs) have resulted in high-resolution digital elevation models (DEMs) of vulnerable coastal environments, including beach–foredune topography. If performed repetitively, they can offer an excellent tool to determine the spatial and temporal changes in the sediment budget, which may be required for proper land management. However, the quality of a UAV, slope parameters, and vegetation significantly influence DEM accuracy. The aim of this study is to compare precise GPS-RTK transects across a section of the South Baltic coast in Poland with those obtained from a DEM based on high-resolution and high-accuracy images obtained by a wind-resistant, high-quality fixed-wing UAV during beyond visual line of sight operation (BVLOS). Different land cover classes, slope inclination, and general curvature, as well as surface roughness, were taken into consideration as possible factors influencing the uncertainty. The study revealed that marram grass greatly affects the accuracy of the UAV-derived model and that the uncertainty of the UAV-derived DEM increases together with increasing slope inclination and, to a lesser degree, with increasing general slope curvature. We showed that sediment budget determinations with the use of a UAV-based DEM are correct only where grass cover is sparse, in our study, up to 20% of the area.
Maria Teresa Markiewicz
In the event of an accident in an industrial plant, the damage caused by it can be enormous. There may be environmental contamination in a large area. Injured persons may be both employees of the plant staying on its premises and local residents. The control of major accidents is realised by implementing the procedures regarding: safety analysis, emergency and operational planning, effective land-use planning (LUP), strategic environmental assessment (SEA), environmental impact assessment (EIA) and public consultation. The paper presents findings of a case study aiming to analyse selected spatial planning documents prepared at the municipality and SEA reports accompanying them, with regard to hazards of major industrial accidents in six Polish cities. In addition, changes of relevant Polish legislation taking place from 1995 till now are explained referring to European Union (EU) law. This article is the very first to present the situation concerning LUP around hazardous plants in Poland based on such extensive data. The assessment shows that the way of recording the major accident hazards is varied, but legal norms, binding at the time when the documents were drawn up, were met in each of the analysed documents. Changes of relevant Poland legislation were not the only reason for differences in the ways of recording the hazards of major industrial accidents in these documents. The case study has revealed that relevant Polish regulations can be still improved. The results of the study have useful implications for the control of major accidents, spatial policy-making and environmental management.
Vishakh Vadakkedath, Jarosław Zawadzki, Karol Przeździecki
On-site monitoring in large areas located in inaccessible regions can be difficult and costly. Thus remote sensing is an essential tool for mapping and monitoring changes in such regions. Therefore, this paper describes long-term multisensory satellite observations of the expansion of the Batagaika crater in Northern Siberia and natural succession of vegetation in its interior from 1991 to 2018. Landsat 5 TM, Landsat 7 + ETM, Landsat 8 OLI/TIRS imageries were mainly used as a data source for analyses, although Sentinel-2A imagery and DEM image from ASTER satellite were also employed for calculating a vegetation index and expansion in the crater area. The observations were conducted in years 1991–2018 and were made in a summer season. The results reveal that the crater area increased by almost three times during these 27 years and that the fastest expansion took place between 2010 and 2014 with 22.7% increment. The analysis of elevation of the crater revealed that in 2018 its maximum depth was ca 70 m and that depth was decreasing towards its north-east tail. Additionally, the satellite imagery of land surface temperature which is a driving force of crater expansion was visualized for chosen hot days within the time frame 2010–2018. The study of temporal and spatial changes in NDVI spatial distributions inside the crater revealed also a high rate of the succession of vegetation, which may reduce melting of permafrost inside the Batagaika crater and its further expansion.
Elżbieta Kubrak, Janusz Kubrak, Adam Kiczko, Michał Kubrak
This study analyzes the possibilities of using an irrigation sluice gate in submerged conditions to measure water flow rate. Hydraulic experiments on sluice gate discharge capacity were performed on a model made on a 1:2 scale. Measurements were taken for the submerged flow of the sluice gate. Nomograms and relationships for discharge coefficients of the analyzed sluice gate were developed. The possibility of using the existing nomogram for discharge capacity of the submerged sluice gate to determine the discharge capacity of the modeled gate was also investigated. The effect of narrowing of the sluice gate cross-section resulting from different mounting techniques on its capacity was explained. The analyses confirmed the possibility of using the formulas for the submerged sluice gate to estimate the flow through the irrigation sluice gate.
Mirosław Maziejuk , Wiesław Lisowski , Tomasz Sikora , Łukasz Osuchowski , Jerzy Sowa , Jacek Hendiger , Halina Kamińska
Three species of ornamental plants (Sansevieria trifasciata, Epipremnum aureum, Dieffenbachia seguine) were used to improve the quality of the air in workplaces. The lab. tests confirmed removal of volatile org. comp. A new measurement techn. enabling continuous monitoring of the quality of the air in spaces was developed.
Accurate and efficient simulation of the hydraulic shock phenomenon in pipeline systems is of paramount importance. Even though the conservation-law formulation of the governing equations is here strongly advocated, the nonconservative form is still frequently used. This also concerns its mathematical conservative form. We investigated the numerical consequences of using the compressible gas flow model in the latter form while simulating a hydraulic shock. In this context, we also solved two Riemann problems. For the investigation, we used the third-, fifth- and seventh-order accurate weighted essentially non-oscillatory (WENO) scheme along with the Lax–Friedrichs solver at the cell interfaces. Both the classical finite volume WENO scheme and its modification WENO–Z have been implemented. A procedure based on the method of manufactured solutions has been developed to verify whether the numerical code solved correctly the hyperbolic set of equations. We demonstrated that the solutions of the conservative and nonconservative formulations are similar if we have smooth variations in the solution domain. The convective inertia term in the momentum equation should not be ignored. In the presence of shocks, differences in oscillating behavior and slope steepness near the discontinuities were observed. For the hydraulic shock problem, spurious oscillations appeared while using the nonconservative formulation in combination with the WENO–Z reconstruction.
Jakub Pulka , Piotr Manczarski , Paweł Stepien , Marzena Styczyńska , Jacek A. Koziel , Andrzej Białowiec
Sewage sludge (SS) recycling is an important part of the proposed ‘circular economy’ concept. SS can be valorized via torrefaction (also known as ‘low-temperature pyrolysis’ or ‘roasting’). SS can, therefore, be considered a low-quality fuel or a source of nutrients essential for plant growth. Biochar produced by torrefaction of SS is a form of carbonized fuel or fertilizer. In this research, for the first time, we tested the feasibility of torrefaction of SS with high ash content for either fuel or organic fertilizer production. The research was conducted in 18 variants (six torrefaction temperatures between 200~300 °C, and three process residence times of 20, 40, 60 min) in 5 repetitions. Fuel and fertilizer properties and multiple regression analysis of produced biochar were conducted. The higher heating value (HHV) of raw SS was 21.2 MJkg-1. Produced biochar was characterized by HHV up to 12.85 MJkg-1 and lower H/C and O/C molar ratio. Therefore, torrefaction of SS with high ash content should not be considered as a method for improving the fuel properties. Instead, the production of fertilizer appears to be favorable. The torrefaction increased C, N, Mg, Ca, K, Na concentration in relation to raw SS. No significant (p < 0.05) influence of the increase of temperature and residence time on the increase of biogenic elements in biochar was found, however the highest biogenic element content, were found in biochar produced for 60 min, under the temperature ranging from 200 to 240 °C. Obtained biochars met the Polish regulatory criteria for mineral-organic fertilizer. Therefore SS torrefaction may be considered a feasible waste recycling technology. The calculation of torrefaction energy and the mass balance shows energy demand <2.5 GJMg-1 w.m., and the expected mass yield of the product, organic fertilizer, is ~178 kgMg-1 w.m of SS. Further investigation should consider the scaling-up of the SS torrefaction process, with the application of other types of SSs.
The study aimed to assess the content of metals in water, suspended solids and bottom sediments sampled from the Wilanowskie Lake. The analyses of zinc, lead, cadmium, and copper showed that the metal concentration in water, suspended solids, and sediments differed at individual measurement points. It can be attributed to the influx of pollutants from the areas adjacent to the lake. During the sampling period, the concentration of dissolved forms of Cu varied from 33.1 to 186.5 μg/dm3; in the suspended form it ranged from 0.21 to 0.81 mg/dm3, and in bottom sediments, it was in the range 17–245 mg/kg dw. For cadmium, the concentration of dissolved forms ranged from 1.15 to 19.53 μg/dm3, in suspended form – from 0.02 to 0.1 mg/dm3, and in the sediments from 6.2 to 21.6 mg/kg dw. The concentration of dissolved forms of lead was from 3.19 to 106.7 μg/dm3, in the suspension from about 0.67 to 1.07 mg/dm3 and in sediments – from 200 to 450 mg/kg dw. For zinc, the results were respectively: from 65 to 632 μg/dm3 for the metal forms dissolved in water, from 1.1 to 2.2 mg/dm3 for suspended forms and from 70 to 2,900 mg/kg dw in sediments.
Marta Wiśniewska, Andrzej Kulig, Krystyna Lelicińska-Serafin
Biogas plants processing municipal waste are an important part of a circular economy (energy generation from biogas and organic fertiliser production for the treatment of selectively collected biowaste). However, the technological processes taking place may be associated with odour nuisance. The paper presents the results of pilot research conducted at six municipal waste biogas plants in Poland. It shows the relations between odour intensity and concentration and the occurring meteorological and ambient conditions (air temperature and relative humidity) and technological factors at biogas plants processing municipal waste. The impact of meteorological and ambient conditions was identified by measuring air temperature and relative humidity and observing their changes. The impact of technological factors was identified by measuring odorant concentration (volatile organic compounds and ammonia) and observing their changes between individual measurement series. At most analysed biogas plants, the influence of technological factors on odour emissions took place and was clearly noted. The elements of biogas installations characterised by the highest concentration of these odorants were indicated. Special attention should be paid to the choice of technological solutions and technical and organisational measures to reduce the impact of unfavourable atmospheric conditions on odour emissions.
Agnieszka Malesińska, Mariusz Wojciech Rogulski, Pierfabrizio Puntorieri, Giuseppe Barbaro, Beata Elżbieta Kowalska
The purpose of this study is to analyze the effect that inserting an elastic tube into a pressure pipeline has on the water hammer phenomenon. This research draws upon theoretical analysis, experimental testing, and numerical simulations. Assuming perfect elastic behavior of the system, the formula for the constant pressure wave velocity in a pipeline with an inserted tube was derived. Experimental tests were carried out, aimed at reducing the pressure increase in the pipeline due to inserting a silicone rubber tube in it. A significant reduction of the pressure increase has been achieved. Theoretical values of the pressure wave velocity were significantly lower than measured. Numerical calculations were performed, the purpose of which was to simulate the course of pressure changes in the pipeline with inserted tube. An approximate model of unsteady flow was used, which relates elastic behavior of water, pipeline, and tube materials to the continuity equation via the variable pressure wave velocity. By taking into account the variable celerity of the pressure wave and diffusive term, it was possible to obtain an acceptable compliance between the experimental data and the results of the numerical calculations.
Michał Kubrak, Apoloniusz Kodura
The purpose of this study is to analyze the effect that inserting an elastic tube into a pressure pipeline has on the water hammer phenomenon. This research draws upon theoretical analysis, experimental testing, and numerical simulations. Assuming perfect elastic behavior of the system, the formula for the constant pressure wave velocity in a pipeline with an inserted tube was derived. Experimental tests were carried out, aimed at reducing the pressure increase in the pipeline due to inserting a silicone rubber tube in it. A significant reduction of the pressure increase has been achieved. Theoretical values of the pressure wave velocity were significantly lower than measured. Numerical calculations were performed, the purpose of which was to simulate the course of pressure changes in the pipeline with inserted tube. An approximate model of unsteady flow was used, which relates elastic behavior of water, pipeline, and tube materials to the continuity equation via the variable pressure wave velocity. By taking into account the variable celerity of the pressure wave and diffusive term, it was possible to obtain an acceptable compliance between the experimental data and the results of the numerical calculations.
C.A.Belis, D. Pernigotti, G.Pirovano, O.Favez, J.L.Jaffrezo, J.Kuenen, H.Denier van Der Gon, M.Reizer, V.Riffault, L.Y.Alleman, M.Almeida, F.Amato, A.Angyal, G.Argyropoulos, S.Bande, I.Beslic, J.-L.Besombes, M.C.Bove, P.Brotto, G.Calori, D.Cesari, C.Colombi, D.Contini, G.De Gennaro, A.Di Gilio, E.Diapouli, I.El Haddad, H.Elbern, K.Eleftheriadis, J.Ferreira, M. Garcia Vivanco, S.Gilardoni, B.Golly, S.Hellebust, P.K.Hopkea, Y.Izadmaneshia, H.Jorqueraa, K.Krajsek, R.Kranenburg, P.Lazzeria, F.Lenartza, F.Lucarelli, K.Maciejewska, A.Manders, M.Manousakas, M.Masiola, M.Mirceaa, D.Mooibroeka, S.Navaa, D.Oliveirac, M.Paglioney, M.Pandolfi, M.Perronea, E.Petraliaa, A.Pietrodangeloa, S.Pillona, P.Pokornaa, P.Prati, D.Salameh, C.Samara, L.Sameka, D.Saraga, S.Sauvage, M.Schaap, F.Scottoa, K.Sega, G.Sioura, R.Tauler, G.Vallia, R.Vecchia, E.Venturinia, M.Vesteniusa, A.Wakedd, E.Yuberoar
In this study, the performance of two types of source apportionment models was evaluated by assessing the results provided by 40 different groups in the framework of an intercomparison organised by FAIRMODE WG3 (Forum for air quality modelling in Europe, Working Group 3). The evaluation was based on two performance indicators: z-scores and the root mean square error weighted by the reference uncertainty (RMSEu), with pre-established acceptability criteria. By involving models based on completely different and independent input data, such as receptor models (RMs) and chemical transport models (CTMs), the intercomparison provided a unique opportunity for their cross-validation. In addition, comparing the CTM chemical profiles with those measured directly at the source contributed to corroborate the consistency of the tested model results. The most commonly used RM was the US EPA- PMF version 5. RMs showed very good performance for the overall dataset (91% of z-scores accepted) while more difficulties were observed with the source contribution time series (72% of RMSEu accepted). Industrial activities proved to be the most difficult sources to be quantified by RMs, with high variability in the estimated contributions. In the CTMs, the sum of computed source contributions was lower than the measured gravimetric PM10 mass concentrations. The performance tests pointed out the differences between the two CTM approaches used for source apportionment in this study: brute force (or emission reduction impact) and tagged species methods. The sources meeting the z-score and RMSEu acceptability criteria tests were 50% and 86%, respectively. The CTM source contributions to PM10 were in the majority of cases lower than the RM averages for the corresponding source. The CTMs and RMs source contributions for the overall dataset were more comparable (83% of the z-scores accepted) than their time series (successful RMSEu in the range 25% – 34%). The comparability between CTMs and RMs varied depending on the source: traffic/exhaust and industry were the source categories with the best results in the RMSEu tests while the most critical ones were soil dust and road dust. The differences between RMs and CTMs source reconstructions confirmed the importance of cross validating the results of these two families of models.
Piotr Manczarski, Krystyna Lelicińska-Serafin, Anna Rolewicz-Kalińska
The objective of the study is research on a biofilter existing at a mechanical-biological waste treatment plant in Radom. The paper presents results of research on the filling of the analysed biofilter (moisture, organic matter content, nutrient content, pH, grain size composition, and equivalent diameter), process gases (temperature, humidity and pH, concentrations of the main pollutants – ammonia, hydrogen sulphide, volatile organic compounds, acetic acid, ethanol) and operational parameters (flow rate, height of the biofilter layer, surface load, gas residence time in the filter bed). Irregularities were observed related to biofiltration efficiency, particularly resulting from improperly selected filling material and improper biofilter operation. The technological research permitted the identification of problems and determination of the requirement of performing necessary operational changes. Further works will involve the design, manufacture, and installation of an integrated biofilter with two-stage gas purification process (a classic biofilter and a semi-permeable membrane).
Jarosław Chudzicki, Katarzyna Umiejewska
Since the 1990s, there have been trends in Central and Eastern European countries to reduce water consumption. This phenomenon is closely related to the political, social and economic changes in these countries and the introduction of economic instruments in water management. The article presents the changes in water consumption in households in the years 1950–2019 depending on the degree of equipping buildings with sanitary facilities, and the structure of water consumption for particular purposes. For the same period, the quality of sewage generated in households is presented on the basis of bibliography. The content of total suspended solids was the main analysed parameter. The last part of the article presents the quality of wastewater discharged to fourteen Polish wastewater treatment plants. The majority of the analysed plants show an increase in the concentration of total suspended solids in the domestic sewage discharged to them. This phenomenon may be influenced by the decreasing water consumption in households.
Ewa Duda, Krzysztof Dziurzyński
Nowadays, the digital competence is becoming as important as literacy and numeracy skills. For children and youths these competences seem to be natural and the role of teacher is to direct students in their learning and to develop cognitive curiosity. For adults, the learning process is different. It is not only developing of digital skills but sometimes even grassroots teaching. The article presents a two different approaches to teaching/learning process provided in the field of secondary education – Finnish and Polish systems. Documents containing curricula, school programmes and course grids were analysed. Both systems have been assessed in terms of their relevance to adult learners. The main discoveries and the key conclusions indicate that the Polish system does not adapt to the real needs of adult learners and the changing needs of the labour market.
Waste management is an important element of sustainable urban development. One of the directions of waste management is mechanical-biological treatment (MBT) of waste with biogas installation. In addition to the benefits of purifying waste from separate collection and sorting of raw material waste from the mixed waste stream (subsequently diverted to recovery or recycling), this direction is also characterised by energy benefits (energy production from biogas). Mechanical and biological treatment of municipal waste inevitably entails also negative impacts, such as odour emission. In Poland, there are no legal regulations concerning odour nuisances. Reference could be made, inter alia, to BAT conclusions on waste treatment or standards in other countries. There are many methods of testing for odour emissions, but none of them, taken individually, characterises it sufficiently. The paper presents the results of research carried out in one of the biogas plants in Poland. The results present the sources of the highest odour emission in the examined plant, to which they belong: digestate during the second-stage oxygen stabilisation in the open air and pump station of technological sludge.
Ferdinand Uilhoorn, Maciej Witek
Structural integrity and risk management have a wide interest because of its practical applications, such as oil and gas pipelines, piping systems under pressure in power stations, urban water, and heating networks. The main goal of this paper is twofold. Firstly, to estimate the unsteady pressureflow variations in a gas transmission grid within the framework of sequential data assimilation. This technique enables to determine accurately the maximum pressure at the localized defect on the pipeline by merging measurements that contain random errors into the inexact numerical flow model. For this purpose, a particle filter is used. The semi-discretization approach is applied to convert the nonisothermal flow model into an initial value problem of ordinary differential equations. The spatial discretization is based on a five-point, fourth-order finite difference approximation and the time marching was done using a diagonally implicit Runge-Kutta scheme. Secondly, to study the strength of steel tubes reinforced with composite sleeves containing localized part-wall thickness losses caused by corrosion while taking into consideration a safe operating pressure. For a steel thin-walled cylinder containing a wrap of fiberglass with epoxy resin, the burst pressure and sleeve thickness are determined. Finally, the repaired pipeline with a fiber-reinforced composite sleeve is investigated. The results enable operators to handle problems of corroded steel pipelines and develop effective repair activities during operation. For this reason, current research is important for the maintenance of underground steel networks.
Janusz Kubrak, Elżbieta Kubrak, Edmund Kaca, Adam Kiczko, Michał Kubrak
This article introduces a flow controller for an upstream water head designed for pipe culverts used in drainage ditches or wells. The regulator is applicable to water flow rates in the range of Qmin < Q < Qmax and the water depth H0, exceeding which causes the gate to open. Qmin flow denotes the minimum flow rate that allows water to accumulate upstream of the controller. Above the maximum flow rate Qmax, the gate remains in the open position. In the present study, the position of the regulator’s gate axis was related to the water depth H0 in front of the device. Derived dependencies were verified in hydraulic experiments. The results confirmed the regulator’s usefulness for controlling the water level.
Piotr O. Czechowski, Piotr Dąbrowiecki, Aneta Oniszczuk-Jastrząbek, Michalina Bielawska, Ernest Czermański, Tomasz Owczarek, Patrycja Rogula-Kopiec, Artur Badyda
This article marks the first attempt on Polish and European scale to identify the relationship between urban and industrial air pollution and the health conditions of urban populations, while also estimating the financial burden of incidence rates among urban populations for diseases selected in the course of this study as having a causal relation with such incidence. This paper presents the findings of a pilot study based on general regression models, intended to explore air pollutants with a statistically relevant impact on the incidence of selected diseases within the Agglomeration of Gdańsk in the years 2010–2018. In discussing the city’s industrial functions, the study takes into consideration the existence within its limits of a large port that services thousands of ships every year, contributing substantially to the volume of emissions (mainly NOx and PM) to the air. The causes considered include the impact of air pollution, seasonality, land- and sea-based emissions, as well as their mutual interactions. All of the factors and their interactions have a significant impact (p ≤ 0.05) on the incidence of selected diseases in the long term (9 years). The source data were obtained from the Polish National Health Fund (NFZ), the Agency for Regional Monitoring of Atmosphere in the Agglomeration of Gdańsk (ARMAAG), the Chief Inspectorate of Environmental Protection (GIOŚ), and the Port of Gdańsk Harbourmaster. The study used 60 variables representing the diseases, classified into 19 groups. The resulting findings were used to formulate a methodology for estimating the financial burden of the negative health effects of air pollution for the agglomeration, and will be utilized as a reference point for further research in selected regions of Poland.
Andrzej Kulig, Mirosław Szyłak-Szydłowski
Methodological aspects of odor studies in ex-post analyses for Polish wastewater management facilities were analyzed based on the example of a modernized and enlarged wastewater treatment plant (WWTP) in Mazovia, in the vicinity of the Warsaw agglomeration. It is a mechanical–biological treatment plant with increased efficiency of biogen removal, using activated sludge in the treatment process, with a maximum hydraulic capacity of 60,000 m3/day. Olfactometric research was carried out by means of a method based on identification and characterization of the odor plume emitted from the examined source. This paper presents the results of odor intensity assessment (in sensory examinations according to a 6-stage scale) and odor concentration measurement (using portable field olfactometers) after the completion of the project, and compares them with similar studies conducted before the commencement of the investment. A total of 10 measurement series were carried out before modernization, and 12 after modernization of the WWTP. Odor concentration and intensity were determined, and the current meteorological situation was assessed at the measurement and observation points (receptors) located within the premises (in total 462 points) and around the WWTP (342 points). In each series of measurements on the windward side of the treatment plant, the background of air pollution with odorous substances was marked. The research showed that air flowing into the area of the sewage treatment plant is clean in terms of odor. During the research, basic sources of odor nuisance were identified, and their impact before and after modernization was characterized. The results presented in radar diagrams show changes in the percentage distribution of frequency of occurrence of individual intensity values at receptor points within and outside the area of the treatment plant. After modernization, a significant decrease in the concentration of odor emitted from the sludge dewatering building and sludge containers was determined. The air-tightness of the sewage channel (covered with concrete slabs and sealed) resulted in a significant decrease in the concentration of odor emitted from this source. Waste (in particular, sewage sludge) collected in the emergency waste storage yard was identified as the main source of odor nuisance. The waste, even after modernization, was an emitter of odorous compounds spreading outside the area of the WWTP. Nevertheless, as a result of the investment, the desired effect of reduction of the degree of odor nuisance was achieved.
Tadeusz Magiera, Adam Łukasik, Jarosław Zawadzki, Wolfgang Rösler
Forest topsoil is subjected to physical and chemical degradation due to the deposition of urban and industrial dust and landfill, as well as physical disturbances including a relic of former cultivation, clearcutting, and afforestation. Such disturbances are observed in all natural and semi-natural forests across Europe, but most intensively in urban forests surrounding cities and industrial areas. Magnetic susceptibility constitutes a convenient physical parameter that is used for both, determination of levels of industrial and urban dust deposition alongside relevant potentially toxic elements (PTEs), and for the precise localization of polluted areas (so-called “hot spots”). Deposited on the soil surface, technogenic magnetic particles (TMPs) contained in different kinds of anthropogenic dusts increase the magnetic susceptibility of polluted topsoil. This effect can easily be measured “in situ” by applying a geophysical (geomagnetic) technique – soil magnetometry – for which magnetic susceptibility is the basic parameter. This technique can be performed inexpensively and rapidly with high spatial resolution at local (e.g., for individual trees, and forest stand areas around pollution sources) and regional (for whole regions or countries) scales. The application of combined magnetic-chemical analyses together with geostatistical methods (especially cokriging methods) can deliver more significant results regarding the spatial distribution of pollution than chemical testing alone. A high degree of correlation between magnetic susceptibility and PTEs content (expressed in the form of Pollution Load Index) significantly improves the level of precision in localizing polluted areas. Knowledge of forest topsoil quality and the use of magnetic susceptibility for the precise delineation of areas with considerable anthropogenic physical and chemical disturbances may facilitate the management application of the ecosystem service concept at local and regional scales.
Marta Wiśniewska, Andrzej Kulig, Krystyna Lelicińska-Serafn
Biogas plants processing municipal waste on the one hand represent a trend in waste management, and on the other hand constitute an alternative energy source. Next to their unquestionable benefits, due to the character of the provided activity, they can be a potential source of odours. Municipal waste, largely containing biodegradable fractions, is often subject to decomposition processes in uncontrolled conditions still before it is supplied to the mechanical biological treatment plant. One of the effects of the processes, both controlled and uncontrolled conditions, is emission of odorants. Their spread depends on the applied technologies and adherence to the technological regime during operation. One of the factors determining the types and concentrations of emitted odorants are also meteorological conditions in which waste is stored and processed. The paper presents results of two series of pilot research conducted at four plants, involving a preliminary analysis of the effect of meteorological conditions on the emission of odorants at biogas plants processing municipal waste.
Grzegorz Kubicki, Izabela Tekielak-Skałka, Marcin Cisek
Purpose: The aim of the analysis was to investigate how smoke would spread in the building in the case of fire, and how to protect staircases without
a pressure differential system (PDS). It was assumed that a ventilation system should:
– prevent the staircase against complete smokiness. The part of the staircase located below the level covered by the fire should be smoke-free to the
extent allowing the evacuation of people from the fire compartments;
– remove smoke from the staircase as fast as possible to prevent a significant increase in the level of pressure in the staircase.
Project and methods: Research was conducted in a full-scale 9-storey building. Three real fires were simulated. Typical apartment furnishings were
used in the fires. A smoke ventilation system was installed in the staircase with variable make-up air supply. Tests were carried out for the following
configurations of smoke ventilation systems:
– natural smoke exhaust with natural/gravitational make-up air;
– natural smoke exhaust with a mechanical (fixed volume of 14000 m3/h) make-up air inlet;
– natural smoke exhaust with a variable mechanical make-up air inlet.
The position of the door between the staircase and the apartment was used as an additional variable.
The measurements included temperature, light transmittance in the staircase, pressure difference between the staircase and the external environment,
and the flow of the air and smoke through the smoke damper.
Results: The results of the research show that the system of gravitational smoke ventilation is susceptible to ambient conditions such as temperature.
In some tests, it was observed that smoke could descend below the storey covered by the fire. The conducted research helped determine the best way
to reduce the amount of smoke in the staircase. The use of mechanical air supply in the smoke ventilation system facilitated fast smoke removal from
the staircase, and the proper air and smoke flow direction (from the test room to smoke exhaust devices).
The use of mechanical make-up air supply in the smoke ventilation system prevented the smoke from descending below the storey covered by the fire, so
that the staircase on the floor covered by the fire could remain free from smoke in the lower part, providing a way of escape from the level covered by the fire.
Conclusions: The conducted tests have revealed that the best solution to protect staircases without PDSs is to use a smoke ventilation system comprising
a smoke vent mounted at the top and mechanically adjusted make-up air supply on the ground level.
Marta Wiśniewska, Krystyna Lelicińska-Serafn
The paper presents examples of installations for the mechanical and biological treatment of municipal waste in Poland. Each of the presented installations is defined as a regional municipal waste treatment installation (RIPOK). Their technological solutions and work efficiency have been compared in this study. In addition, the loss of waste mass as a result of processes occurring in the biological part of individual installations was calculated in the research. The paper refers to the National Waste Management Plan (KPGO 2022) regarding the circular economy. As intended by the circular economy, MBP installations will be transformed into installations that will treat selectively collected municipal waste and become Regional Recycling Centers (RCR).
Wojciech Dąbrowski, Beata Karolinczak
In Poland, as well as across the whole world, an increase in craft beer production can be observed. In the last several years more than 150 of such breweries have appeared and according to Polish Brewery Association their number might ultimately reach 500. Many of them emerge in areas with no access to a central sewerage system so they have to solve the problem of waste management on their own. The article presents the results of research on the possibility of using a hybrid system for biological treatment of sewage from craft breweries. The sewage came from a craft brewery Waszczukowe located in Podlaskie province. A laboratory scale model consisted of a trickling filter (TF) (research model Gunt CE701e) and vertical flow constructed wetland (SS-VF). Innovative filling (Certyd produced by LSA company) of TF and SS VF was applied. The conducted study included determining changes in sewage parameters during hybrid treatment, as well as TF and SS VF efficiency separately. The aim of the research was to show the possibility of treating sewage to a point when it was possible to discharge it to a receiver, in compliance with Polish legal regulations. The research results might be used in designing a treatment system or sewage pretreatment in craft breweries. The average efficiency of TF operating with 100% recirculation was 76% for BOD5, 80% for COD, 26% for TN and 34% for TP while the total treatment efficiency of a hybrid system (TF and SS-VF) was 98%, 98%, 72% and 77% respectively. The load of TF during operation with recirculation was on average 0.38 kg BOD5 m-2d-1, 0.57 kg COD m-2 d-1. The load of SS-VF was on average 0.09 kg BOD5 m-2 d-1 and 0.12 kg COD m-2d-1. The obtained results of hybrid treatment permitted to discharge the sewage to the receiver.
Małgorzata Kwestarz, Maciej Chaczykowski
The power systems in European Union operate under energy policies where the greenhouse gases reduction, the increase of the share of renewable energy sources (RES) and the improvements in energy efficiency are the main objectives. Polish energy sector is currently based on inefficient usage of coal and must be transformed according to the requirements of EU energy and climate policy. A policy framework for climate and energy in the period from 2020 to 2030 established the target of 27% of share of RES in energy consumption. With the continuing increase in the use of RES, it is likely that more and more generation will have to be curtailed to maintain the stability of the power system which was not originally designed to integrate renewable generation. In this context, the conversion of renewable electricity to heat in connection with its storage in district heating systems, known as Power-to-Heat (PtH) can be considered as a viable option in increasing the share of RES and facilitating the stability of the power system. In this paper an attempt is made to estimate the potential of PtH technology for Poland up to 2030, including the high RES share scenario for the energy mix development.
Monika Żubrowska-Sudoł, Agnieszka Garlicka, Justyna Walczak, Katarzyna Sytek-Szmeichel, Aleksandra Mikołajczak, Michał Stępień, Piotr Krawczyk, Katarzyna Umiejewska, Marcin Wołowicz
This paper presents the results of the first stage of the project, aimed at the assessment of the applicability of the new apparatus for disintegration of excess waste activated sludge. It was documented that the analysed device allows for disintegration of sewage sludge with an efficiency comparable to that obtained in other devices dedicated for mechanical disintegration of sewage sludge described in the literature. The disintegration process at energy density in a range of 35–210 kJ/l resulted in the release from activated sludge flocs of 219–515 mg SCOD/l for 35 kJ/l to 2138–4884 mg SCOD/l for 210 kJ/l.
Ryszard Zwierzchowski, Olgierd Niemyjski
The paper presents a simulation of heat losses of a distribution network with different technical structure and under different operating conditions for a District Heating and Cooling (DHC) system. The DHC system consists of a Combined Heat and Power (CHP) plant and a Distribution Network (DN) with chambers and heat and cold substations. The different operating conditions of the DHC systems result in the DNs having variable transportation losses. The result of the analysis was used to verify the models and calculation methods of the fluid flow and heat losses in the DN, when cold is generated using either absorption or adsorption chillers. Different technical structure of a DN means a system of connected underground and aboveground piping with different diameters. DNs in Poland are usually installed as an underground, traditionally insulated piping placed in the concrete ducts (large diameter main pipelines) or a pre-insulated piping placed directly in the ground. The total heat losses of the DN differ according to the individual systems and depend on the size of the DHC system, its heating loads and quality of insulation of the piping. This paper presents the results of the numerical calculation of the temperature distribution in the soil around the piping channel using an FDA model. These results were utilized for numerical simulation of the water and heat flow through the DN and calculation of heat transportation losses. The numerical simulation of heat losses was performed for the particular system of connected underground and aboveground piping with different diameters. Finally, the heat transportation losses of the DN were calculated and compared for analyzed District Heating (DH) system i.e. without cold consumers and for the DHC system, when cold for consumers is generated using either the absorption or the adsorption chillers.
Ryszard Zwierzchowski, Michal Pachocki
Increasing the energy efficiency of industrial installations is one of the European Union’s priorities for achieving energy policy goals. These goals can be achieved, among others, by applying the appropriate methodology for modernization of cooling water distribution pipelines and improving their operation. Water distribution in cooling systems of large industrial installations is associated with significant hydraulic losses due to large flows and spatial spread of these systems. The losses are unavoidable and have a decisive impact on the energy consumption for pumping. Thanks to optimal design solutions, implementation of the repair program and proper operation of cooling water transmission pipelines, it is possible to significantly reduce hydraulic losses and water leakage. This will translate into reduced energy consumption for pumping and, as a result, improved energy efficiency. Abovementioned goals can be achieved by replacing or renovating pipelines. This paper deals with determination of a method and schedule of modernization of cooling water piping systems on the basis of a case study – a large industrial plant. Firstly, evaluation of the existing condition is carried out. Data on flow rate and cooling water pressure in the system are collected and analyzed. A graphical and numerical database of the cooling water system is made, which maps the system in terms of system geometry (lengths, pipe diameters, ordinates) and flow and pressure streams. The hydraulic losses of the cooling water system are simulated. The results of simulation calculations of pressure losses in water distribution system are presented in the form of maps of water pressure distribution in pipelines. Calculations for the pipeline network are performed in the current state for two hydraulic load cases: maximum and average. An assessment of the failure rate is made on the basis of information about the place, time, cause and type of damage. Wall thickness of pipelines in selected locations is measured and samples are taken from pipes in places of failure. The reasons for water pipeline failures are diagnosed. On the basis of pre-modernization simulation, information on failure rate and forecasts of future water demand are obtained, it is proposed which pipeline sections and in what order should be modernized. Depending on the technical condition, pipeline diameter and location in the field, pipe replacement or renovation is recommended. For pipes to be replaced, new diameters, adjusted to the forecasted demand are calculated. For pipes qualified for renovation, different site hardened liners or full wall pipes are recommended depending on pipe condition. Renovation methods, despite the reduction of the internal cross-section, provide similar or lower hydraulic resistance values. After selecting the variants of modernization of distribution pipelines, hydraulic simulations are carried out in the post-modernization condition, taking into account the future demand for cooling water. The presented method can be applied to cooling water systems as well as other industrial water piping systems.
Ryszard Zwierzchowski, Marcin Malicki, Maciej Lipka
The paper introduces an innovative conceptual model of a trigeneration system based on implementation of sorption devices in cascade configuration: absorption heat pumps and adsorption chillers connected with thermal energy storage, for recovering useless heat from secondary cooling circuit of a research nuclear reactor. Proposed trigeneration source provides building with useful heat for the purposes of heating system with thermal energy storage and cold for air-conditioning purposes. Also, desalinated water covering technological demand is produced. Useful heat is produced by an absorption heat pump, cold and desalinated water by adsorption chiller/desalinator. For the described trigeneration system calculations based on commercially available equipment (lithium-bromate absorption heat pumps and silica-gel adsorption chillers with desalination option) and required heat/cold/desalinate demand have been carried out. Operational data collected from an existing installation extended by introducing thermal energy storage to the system was used to simulate the heat demand during the year. 5-year operational data from the “MARIA” research nuclear reactor located at the National Center for Nuclear Research in Świerk, Poland was used to simulate low source variations for the absorption heat pump operation. The results of model implementation demonstrate a series of promising effects on many levels of system operation, including production of desalinated water on a large scale and significant reduction of: (I) energy usage (by 40% when considering only heating scenario), (II) nuclear fuel consumption, (III) heat delivery losses.
The paper contains a method for improvement of operation of steam cushion system including its energy savings analyses, for a Thermal Energy Storage (TES) tank. Energy savings analyses were performed using operational data from selected Combined Heat and Power plants, which supply heat to large cities in Poland and are furnished with the TES. The role of the steam cushion system in the TES tank is to prevent the stored water against absorbing oxygen from atmospheric air. In the TES tank, which is a non-pressure tank, oxygen from atmospheric air could penetrate to the network water through the surge chamber and safety valves. The steam pressure under the roof is generated from technological steam injected under the roof. Energy savings in the steam cushion system are generated by using an appropriate technical solution for the upper orifice and suction pipe for circulation water, i.e., to make it movable through the use of pontoons. An isolating buffer layer is created at the top of the tank with very small convective and turbulent heat transport, which causes limited heat transfer from steam bed to the stored water in the tank. This results in heat flux of approximately 10% of the heat flux that occurs in the typical technical solution of the upper orifice and suction pipe for circulation water in the TES tank. This technology offers great opportunities to improve the operating conditions of District Heating System, cutting energy production costs and emissions of pollutants to the atmosphere.
Wastewater from breweries usually contains high levels of organic components, which are generally easily biodegradable. Ideally, the mainstream method of brewery wastewater treatment is based on biological transformation, which have been reported to be effective in efficiently reducing COD concentration. Anaerobic digestion technology plays an important role in the treatment of high strength wastewater . The benefit of the process is biogas production and recovering the energy. The main goal of the paper is to present the results of a full-scale research performed in a brewery WWTP in 2016. Wastewater from brewery containing COD, a priority pollutant of organic components, is treated in IC reactor. The biogas produced during the anaerobic digestion is transformed into heat. Total COD and soluble COD were measured 5 days a week in wastewater before and after anaerobic reactor. In raw wastewater, average total COD was 5226 mg/L with the percentage share of soluble COD 89.4%. As a result of anaerobic treatment 83,7% reduction of total COD and 92.9% reduction of soluble COD were obtained. The average daily biogas production was 4089 m3/d.
Piotr Fabijańczyk, Jarosław Zawadzki
This paper presents a new approach to the assessment of the uncertainty of using geostatistical Gaussian simulation in soil magnetometry. In the study area, numerous measurements of soil magnetic susceptibility were made, and spatial distributions of soil magnetic susceptibility were simulated. The parameters of variograms of soil magnetic susceptibility measured in the study area were determined and compared with those of simulated soil magnetic susceptibility. Regardless of the measurement scheme used, reproducibility of the original semivariograms of soil magnetic susceptibility was satisfactorily achieved when applying simulated values. A nugget effect, a sill, and a range of correlations of variograms of simulated values of soil magnetic susceptibility were similar to those of measured values. When the input data for the geostatistical simulation were averaged, the measured values of soil magnetic susceptibility and simulated spatial distributions were characterized by slightly lower standard deviations in comparison with the result of simulations based on the non-averaged, measured ones. At the same time, however, local variability of soil magnetic susceptibility was reproduced less. The accuracy of the calculations of point parameters and spatial distributions—based on the averaged values of soil magnetic susceptibility—were satisfactory, but when using geostatistical methods, it is recommended to use non-averaged magnetic susceptibility measurements.
E. Pisoni, C. Guerreiro, S. Lopez-Aparicio, M. Guevara, L. Tarrason, S. Janssen, P. Thunis, F. Pfäfflin, A. Piersanti, G. Briganti, A. Cappelletti, I. D’Elia, M. Mircea, M.G. Villani, L. Vitali, L. Matavž, M. Rus, R. Žabkar, M. Kauhaniemi, A. Karppinen, A. Kousa, O. Väkevä, K. Eneroth, M. Stortini, K. Delaney, J. Strużewska, P. Durka, J.W .Kaminski, S. Krmpotic, S. Vidic, M. Belavic, D. Brzoja, V. Milic, V.D. Assimakopoulos, K.M. Fameli, T. Polimerova, E. Stoyneva, Y. Hristova, E. Sokolovski, C. Cuvelier
This paper presents the first outcomes of the “FAIRMODE pilot” activity, aiming at improving the way in which air quality models are used in the frame of the European “Air Quality Directive”. Member States may use modelling, combined with measurements, to “assess” current levels of air quality and estimate future air quality under different scenarios. In case of current and potential exceedances of the Directive limit values, it is also requested that they “plan” and implement emission reductions measures to avoid future exceedances. In both “assessment” and “planning”, air quality models can and should be used; but to do so, the used modelling chain has to be fit-for-purpose and properly checked and verified. FAIRMODE has developed in the recent years a suite of methodologies and tools to check if emission inventories, model performance, source apportionment techniques and planning activities are fit-for-purpose. Within the “FAIRMODE pilot”, these tools are used and tested by regional/local authorities, with the two-fold objective of improving management practices at regional/local scale, and providing valuable feedback to the FAIRMODE community. Results and lessons learnt from this activity are presented in this paper, as a showcase that can potentially benefit other authorities in charge of air quality assessment and planning.
Krystyna Lelicińska-Serafin, Anna Rolewicz-Kalińska, Piotr Manczarski
This study aimed to assess the efficiency of removal of volatile organic compounds (VOCs) from process gases from a food industry plant in East Poland, producing high-quality animal (goose, duck, and pig) and vegetable fats, using a two-stage method which is a combination of biological purification and membrane-separation. The research, conducted on the semi-technical scale, compared the effects of traditional and two-stage biofiltration carried out under the same process conditions. The concentrations of VOCs in process gases were measured by means of a multi-gas detector. Additionally the temperature and humidity of gases were determined by a thermoanemometer under filter bed, following the EU and Polish National Standard Methods Two different types of filling materials (the mix of stumpwood chips and bark, and the mix of stumpwood chips, bark, and compost) and two types of membranes (three-layer semi-permeable membrane fabrics were used, with differences in air permeability and water tightness) were analyzed. During all processes basic operational parameters, the biofilters were controlled, including surface load, volumetric load, duration of gas contact with the filling layer, flow rate, and pressure drops (in the biofilter and on the membrane). The analyzed gases were characterized by very high variability of VOC concentrations (ranging from 350 ppb to 11,170 ppb). The effectiveness of VOC removal (REvoc) was calculated by comparing the analytical results of raw and purified gases. The effectiveness of VOC removal with the application of traditional biofiltration during the experiment varied between 82% to 97% and was related to different parameters of the filling materials (mainly specific surface and moisture), reaching lower value for the mix of stumpwood chips and bark filling. The obtained results showed that the application of membrane improved the efficiency of biofiltration in all the analysed cases from 7% to 9%. The highest effectiveness was obtained using the filter bed in the form of stumpwood chips, bark, and compost in connection with the more permeable membrane. It was maintained between 96% to 99%, reaching an average value of 98%. The selection of the membrane should be determined by its permeability and the values of flow resistance.
Magdalena Juszczak, Mirosław Szyłak-Szydłowski
The paper presents the results of the spread of the tetrahydrothiophene (THT) – used as odourant – in the gas network. Such analyses allow quick detection of leaks in networks, systems and devices of gas supply directly
to consumers. The main goal of the study was to determine the effectiveness of the use of portable chromatograph and comparing it with a stationary odourant concentration analyser. Based on these studies, an attempt to determine the odouration zone for the selected city have been also taken. For this purpose, three series of measurements were made – in each series 13 points were analysed. Obtained results confirmed the effectiveness of the measurement a concentration of odourant in the gas network using a portable gas chromatograph – difference in relation to the stationary chromatograph ranged from 1.91 to 2.55 %.
Agnieszka Malesińska, Mariusz Rogulski, Pierfabrizio Puntorieri, Giuseppe Barbaro, Beata Kowalska
Pipe lines are useful for transporting water for drinking, irrigation and for fireing over long distances, this pipe lines are called “Transmission line” and are used to carry conveying raw or treated water from a well field or remote storage (large lake, reservoir, etc.,) facility to a treatment plant and/or distribution storage tank. In water-carrying piping systems, dangerous phenomena may occur. One such phenomenon is water hammer.
The water hammer has always been an area of study, which has captivated the minds of researchers due to its complex and challenging phenomena. Modeling the phenomenon in real conditions is extremely difficult. Due to the dimensions of the piping systems, conducting research at real scales is impossible. However, thanks to the development of numerical methods, the study of water hammer and its effects can be performed using simulation programs. Unfortunately, the simulation results are not always consistent with the actual course of the phenomenon.
One of the parameters that describes the nature of the course of a water hammer is the velocity of propagation of the pressure wave, c, which is called celerity. The transient surge pressure, p, may be calculated from the pressure celerity c, and the sudden change in fluid flow velocity, ∆ v. In a piping system, the value of the pressure wave celerity is not equal to the individual celerity, c, for a single pipeline. Therefore for piping systems for ∆p calculations the equivalent celerity shell be used.
This article presents value of the equivalent celerity calculated from equations derived using linear analysis of natural vibrations of the system. For implement of the equations, an algorithm in MATLAB has been developed that allows one to easily calculate the equivalent celerity, ce, for N pipelines connected in series with varying diameter, length and material composition.
Krzysztof Radzicki, Łukasz Rybiański, Paweł Popielski
The thermal method is nowadays the only one that allows precise location of leaks in a shorings of a planned deep excavation, still before this excavation is made. It also allows to determine the leak intensity. As a consequence, it enables precise and early repair work, especially sealing. It allows to prevent or significantly reduce the serious consequences and losses resulting from a leaky excavation shoring. The paper presents the first in Poland case of the thermal detection of leaks in the excavation shoring at a construction site. This method has proven very effective in solving this complicated problem. The leaks were many and occurred in the diaphragm wall as well as under its lower edge. The depth of their occurrence reached over forty meters. The substrate‘s geology was highly heterogeneous. The method produced accurate details about the locations and intensity of the leaks.
Apoloniusz Kodura, Katarzyna Weinerowska-Bords, Wojciech Artichowicz, Michał Kubrak, Paweł Stefanek
This paper presents a numerical model of transient flow in a pressure slurry pipeline network with verification based on in situ measurements. The model, primarily verified in laboratory conditions, has been extended and applied to the case of a large and complex slurry pipeline network in Poland. In the model, the equivalent density concept was applied. In situ experiments were performed for various unsteady flow episodes, caused by different pump operation strategies in the industrial pipeline network. Based on the measurements of slurry concentration and pressure variations, the numerical model was tested and verified. A satisfactory coincidence between the calculated and the observed pressure characteristics was achieved. Additional numerical tests led to important conclusions concerning safe pump and valve operation and system security threats.
Agnieszka Machowska, Zbigniew Kledyński, Iwona Wilińska, Barbara Pacewska
The results of a study on the early hydration process of pastes composed of ground granulated blast furnace
slag and fly ash from fluidized bed combustion of brown coal are presented here. The results of the tests concerning
setting time, hydration processes (spectroscopy, calorimetry and thermogravimetry) and mechanical strength confirm that the
hydration process occurs and solid microstructures and hydration products (hydrated calcium silicates and aluminosilicates,
sulphoaluminates and calcium hydroxide) are formed. The presence of calcium carbonate was confirmed. Increasing the
amount of fly ash in pastes intensifies the process of early hydration, thereby accelerating the initial setting time and
increasing the amount of water bound in hydration products. The early compressive strength is also improved. For example,
the specimen containing the highest amount of fly ash showed a decrease in the initial setting time by about 20% and an
increase in the 2-day compressive strength by 22%, compared to the specimen containing the lowest amount of fly ash.
Michał Sobieraj, Marian Rosiński
A high phase-separation efficiency auto-cascade refrigeration (ACR) system working with a zeotropic mixture of CO2 is proposed in this study. The selection of a high boiling-point component is analysed. A novel zeotropic mixture consisting of a high CO2 (R744) mass fraction together with isobutane (R600a) as a carrier fluid is proposed. An experimental setup was designed, built, and verified to study the ability of the ACR to provide isothermal refrigeration at temperatures lower than the R744 triple-point temperature. The setup employs a recuperative heat exchanger (RHX) for the maximum phase-separation efficiency. The effect of the refrigerant mass charge on the ACR operation was examined. The temperature distribution across the internal heat exchangers (IHXs) was studied as well. The results revealed that the system was very sensitive to the refrigerant mass charge. With a low mass charge, the ACR did not operate correctly owing to the pinch points occurring between the hot and cold ends of the IHXs. High mass charge resulted in increased power consumption and a decreased coefficient of performance (COP). Moreover, tests were conducted to examine the ability of the ACR system, working with a binary mixture of R744/R600a, to provide isothermal refrigeration with different evaporator heat loads. The ACR system was compared in terms of the evaporation pressure and mass flow to a cascade system working with trifluoromethane (R23) in the low stage. The ACR system can be a promising alternative to cascade systems working with R23. The mixture of R744/R600a presented a significant decrease in the global warming potential (GWP) compared with R23. Near-isothermal evaporation was possible with this mixture over a range of vapour quality values. The application range of CO2 was extended to temperatures lower than the CO2 triple-point temperature, using isobutane as a solvent for dry ice. The enthalpy–mass fraction diagrams incorporating a solid fraction area were constructed for the graphical representation of the ACR system.
The aim of this study was to analyse the work of the MultiRAEPro gas detector in terms of its application in monitoring odour emissions from biogas plants processing municipal waste constituting part of a mechanical–biological waste treatment plant. The obtained results provided the basis for formulating conclusions concerning the use of a gas detector in monitoring odour emissions from biogas plants processing municipal waste. The study results can be applied in practice in biogas plants processing municipal waste as well as in other municipal facilities.
Łukasz D. Kaczmarek, Paweł Popielski
Stability of slopes is a topical and substantial issue, affecting areas where there are natural slopes as well as man-made slopes in urban areas, e.g. railway and road embankments, deep excavations or dams [1, 2, 3]. In these all cases, there are a large number of factors influencing the final safety factor value. Furthermore, numerical evaluation of the slope equilibrium state requires accurate representation in a computational model of soil and water conditions, which are determined by the geological structure. This is particularly important in areas which have been tectonically active or subject to intensive geodynamic processes in their geological history [e.g. 4, 5, 6, 7]. This is due to the potential occurrence of peculiar geological features, such as soil layers with reduced strength parameters [e.g. 8], layering associated with strength anisotropy [e.g. 9] and the presence of fault or discontinuity zones in the soil or rock mass [e.g. 10, 11]. For this reason, numerical models often do not adequately replicate real geological conditions. As a consequence, the modelled equilibrium state may not accurately correspond to reality and the computational geometry of the mass movement slip surface may be incorrect.
Moreover, in numerical modelling there are various consequences deriving from the calculation method selected for slope stability analysis, as discussed in  and . Appropriate definition of the slope numerical model is also important (including: right type, sufficient number and proper size of finite elements). These aspects of modelling were discussed by the authors in an earlier publication .
This paper presents universal multistep significance analyses of the impact of individual specific soil and water conditions of a theoretical slope on its stability, expressed in terms of safety factor (SF). An evaluation of this type should be conducted in each case where there is a complex geological structure, on the basis of a properly planned parametric analysis, taking into account different cases of selected geological features.
Piotr Marcinowski, Jan Bogacki, Maciej Majewski, Jarosław Zawadzki, Sridhar Sivakumar
Pollution released into the environment as the result of the combustion of energy fuels is a significant global threat. For instance, wastewater in coal–fired power plants is often heavily polluted by organic compounds, heavy metals and boron. Therefore, there is an urgent need for efficient flue gases and wastewater treatment. However, to be industrially implemented, the treatment processes have to be simultaneously effective and inexpensive. This research systematically studied the efficiency of inexpensive coagulation processes using aluminum-based coagulants applied to flue gas desulfurization (FGD) wastewater treatment. Additionally, the differences in the efficiency of total organic carbon (TOC) and chemical oxygen demand (COD) removal between sedimentation and coagulation processes were systematically studied. It was found that coagulation with the appropriate dose of PAX19XL coagulant achieved a satisfactory effect with significant boron removal and almost complete heavy metals removal. The polyelectrolyte use did not improve coagulation effectiveness and did not accelerate sludgesedimentation and volume decreasing. The detailed statistical analyses did not confirm the positive, pronounced effect of coagulation compared to sedimentation, although there were observed exceptions that should be considered separately. The results obtained suggest that inexpensive aluminum-based coagulants may be effective in improving the efficiency of flue gas desulfurization wastewater treatment in coal–fired power plants.
J. Sowa, J. Hendiger, M. Maziejuk, T. Sikora, Ł. Osuchowski, H. Kamińska
Plants are the planet’s source of oxygen and the sink that removes carbon dioxide produced by burning, respiration and decay of organisms. The studies performed in small chambers indicated that plants also reduce volatile organic compounds (VOC’s). All these phenomena result in a fact that potted plants have a potential to improve IAQ and to some extent to support ventilation. Trends to “go green” increase the growing interest in the introduction of a large number of plants to offices. One should remember that work in modern offices is often associated with a high level of stress. Ornamental plants give highly significant reductions in negative mood states – reductions in anger, anxiety, depression, confusion, fatigue and stress. Leaves provide also additional sound attenuation and cooling effect due to evaporation. The paper summarises the R&D project devoted to the development of the efficient, safe and competitive systems of biofiltration based on the properties of potted plants. The paper presents examples of laboratory tests and describes first experiences from applications in two pilot office buildings.
Adam Muszyński, Piotr Marcinowski, Justyna Maksymiec, Klaudia Beskowska, Ewa Kalwarczyk, Jan Bogacki
Wastewater from a cosmetic factory, with an initial chemical oxygen demand (COD) of 1140 mg/L, was treated using a combined light/Fe0/H2O2 process followed by biological treatment. The light/Fe0/H2O2 process, with 1000/2280 mg/L Fe0/H2O2 doses and 120 min process time, resulted in 70% COD removal, to final COD of 341 mg/L. The chemically treated wastewater was successfully subjected to biological treatment in a sequencing batch reactor (SBR), with up to 20% volume fraction in the influent, without significant deterioration of COD, nitrogen and phosphorus removal, but with possible small negative effects on polyphosphate accumulating organisms (PAOs), nitrifiers and other bacteria present in the microbial community. The COD of the effluent was in the range of 14–28 mg/L, resulting in overall COD removal of up to 97.7%. Untreated cosmetic wastewater, subjected to biological treatment in SBR, caused crucial changes in the microbial community structure, leading to a significant decrease in the efficiency of organic carbon, nitrogen and phosphorus removal.
Arkadiusz Weglarz, Pawel Gilewski
In the changing world, the construction sector undergoes significant changes. New innovative technologies must be introduced, so this sector meets the requirements of sustainable development. In this article, we provide a comprehensive overview of various aspects of methods and techniques that when applied help to achieve the ambitious goals in terms of sustainability. Those aspects are methods applied to the support the design process of buildings, innovative building materials, modern installation systems, building management systems, and systems for managing the process of building operation.
The paper presents the methodology and results of cost-effectiveness analysis of selected methods of wastewater treatment: activated sludge and biofi lter. The analysis concerns small municipal wastewater treatment plants with capacity of 10 to 500 m3d-1 in Poland (~100 to 5000 PE). It is based on data on total investment outlays, annual operating costs and total average annual costs. It has been shown that, in the case of investment outlays, there are no statistically signifi cant differences between technologies. However, the annual operating costs and the total average annual cost of wastewater treatment are the lowest when applying the biofi lter technology. The models presented in the paper can be used for costs estimation at the initial stage of designing municipal wastewater treatment plants. The total average annual cost of wastewater treatment determines the charges for sewerage services. This charge, alongside technological and environmental factors, as well as local conditions, should be one of the criteria for choosing a method for wastewater treatment.
Piotr Fabijańczyk, Jarosław Zawadzki, Tadeusz Magiera
The paper presents systematic study concentrations of selected rare-earth elements, namely La and Ce in soils of highly industrialized regions using geochemical and magnetometric measurements as well as geostatistical methods. Soil magnetometry was used to determine if the concentrations of La and Ce in soil could be a result of anthropogenic pollution or natural soil properties. Results of analyses revealed that the highest concentrations of La and Ce were observed near a waste heap of the plant producing and processing batteries, and in the region of the Jizera Mountains, natural REE-rich minerals are very common. It was also found that the lowest concentrations of La and Ce in soil were observed in forested areas of where the dominant type of pollution sources was associated with the metallurgical industry. Distributions of magnetic susceptibility in soil profiles collected in areas with predominant industrial influence showed visible peak in topsoil, what confirmed anthropogenic origin of La and Ce in soil. In areas where large volumes of wastes were deposited in past, industrial activity, vertical distributions of soil magnetic susceptibility showed also secondary, strong peak in subsoil. Thus, the results reveal that magnetometric measurements in soil profile might be useful as supplementary method for analyzing of concentrations of rare-earth elements. Contrary, magnetometric measurements performed on the soil surface were poorly correlated with a concentration of La and Ce in soil, because they have weaker magnetic properties than typical fly ashes emitted by industry.
Ryszard Zwierzchowski, Olgierd Niemyjski
This paper deals with different operating conditions of a District Heating and Cooling (DHC) System and its influence on heat transportation losses of a District Heating Network (DHN). The different operating conditions of the DHC System’s mean different flow rate and temperature of the network water flowing in the DHN. These different operating conditions of the DHC System result in the DHNs having variable transportation losses. The analyzed DHC System consists of the Heat Only Boilers (HOB) plant and the DHN with substations and chambers. The DHNs in Poland are usually installed as underground, traditionally insulated piping placed in concrete ducts (large diameter and main pipelines) or pre-insulated piping placed directly in the ground. The result of the analysis was used to verify calculation methods of fluid flow and heat transportation losses of the DHN, when cold for consumers is generated using either absorption or adsorption chillers. The total heat transportation losses of the DHN differ according to individual systems and depend on the size of the DHC System, its heating loads and quality of insulation of the piping. This paper presents the results of the numerical calculation of the temperature distribution in the soil around the piping channel using an FDA model. The results of the numerical simulation of water and heat flow through the DHN allow to determine the total heat transportation losses of the DHN for different operating conditions of the DHC System.
Marian Kwietniewski, Katarzyna Miszta-Kruk, Kaja Niewitecka, Mirosław Sudoł, Krzysztof Gaska
The security of water delivery of the required quality by water supply networks is identified with the concept of reliability. Therefore, a method of reliability evaluation of water distribution of the required quality was developed. The method is based on the probabilistic character of secondary water contamination in the water supply network. Data for the method are taken from monitoring of the water distribution system. The method takes into consideration the number and locations of individual measurement points and the results of the tests of water quality indicators at these points. The sets of measurement points and water quality indicators constitute a matrix research (observation) field in the model. The proposed method was implemented to assess the reliability of a water distribution process with respect to water with the required microbiological quality indicators in a real distribution system.
Marta Wiśniewska, Andrzej Kulig, Krystyna Lelicińska-Serafn
Anaerobic digestion of the organic fraction from municipal solid waste offers the possibility of producing alternative energy from the produced biogas. Currently, there are eight biogas plants in Poland, where municipal waste is the feedstock for the fermentation process, but in the future, it is likely that much more will be built. For this reason, it is very important to characterise the sources of odour emissions in the plants in order to prevent complaints from residents of the region. The paper presents results of preliminary research in the field of identification and characteristic of odour sources in two selected biogas plants processing municipal waste in Poland: Wólka Rokicka-WR and Stalowa Wola-SW. The basic sources of odour were identified in relation to the biological treatment process and the pre-treatment of waste. The odour intensity and the concentration of odour and leading impurities were analysed. Results of the research of various technological solutions carried out in biogas plants were compared. The majority of big concentrations of odour and odorants are related to the operation of the biological part of both plants. The study revealed a strong dependency between the applied operation procedures, technological regime and the obtained measurement results. The highest correspondence between the results was obtained in both tested installations in the case of odour intensity and odour concentration, and in the case of concentration of NH3 and VOC.
Ferdinand Evert Uilhoorn
In this work, we introduce a multiobjective optimization approach that seeks the optimal process noise statistics in the extended Kalman filter (EKF). The bi‐objective Mesh Adaptive Direct Search (Bi MADS) algorithm was used to minimize a performance index based on state estimate errors. The EKF estimated the gas flow dynamics in a pipeline system. Simulations were conducted with outflow boundary conditions for the flow model that contain gradual changes and discontinuities. To ensure shock‐capturing properties, the model was approximated with a semidiscrete finite volume scheme using Roe’s SUPERBEE limiter. The knee point in the Pareto front was based on normal boundary intersection approach and selected to compute the flow estimates. Numerical experiments demonstrated that Bi MADS is suitable for tuning the EKF and, compared to the normalized weighted sum method and nondominated sorting genetic algorithm, it showed to be superior in terms of computation time and most effective in finding Pareto optimal solutions.
M. Rogulski, A. Badyda
Air quality is a serious problem in modern cities due to the significant impact of air pollution on the health of the population, the global environment and economy. Recent studies point to the crucial role of information about pollution on micro level, which translates into direct exposure of people to air pollutions. To provide such information, it is necessary to create real-time systems with large spatio-temporal resolution, since such information cannot provide conventional measurement systems performing measurements according to the legislative regulations of particular countries. Current researches focus on the concept of a next-generation air pollution monitoring systems that use new measurement technologies and techniques for communicating and delivering data. These systems can be complementary to traditional air quality monitoring systems. The article presents current trends in the world in this area – the example of static, social and vehicle measurement systems. There are also shown Polish initiatives related to environmental quality monitoring.
Paweł Marcinkowski, Adam Kiczko, Tomasz Okruszko
Multi-channel rivers support diverse and productive ecological communities, and their rareness in the developed world places a great importance on their conservation. The design of side channel restoration projects remains poorly informed by theory or empirical observations. One of the last examples of anastomosing rivers in Europe is a stretch of River Narew in Poland protected as a national park. Park Authorities face a problem of side channels extinction in last few decades and therefore a dedicated plan of protection measures (submerged weir construction, dredging and mowing of side channels) was established aimed at anastomosing system conservation. The objective of this study was an ex-ante assessment of the impact of proposed protection measures on discharge distribution, flow velocity and sediment transport potential in the anastomosing section of the river, using a hydraulic, one-dimensional model. Among the tested measures, more invasive dredging and damming were significantly more efficient than less invasive vegetation removal. Compared to other restoration projects of multi-channel rivers (Narew and Rhône cases), supported by extensive post-restoration monitoring, efficiency level was comparable reaching on maximum tenfold increase in discharge and fivefold increase in reach-averaged flow velocity in restored side channels. Post-conservation alterations of hydraulic properties in the anabranches resulted in a significant increase in sediment transport potential for measures changing channel geometry. Such change could potentially ensure the stability of restoration eliminating the main cause of channels extinction i.e. excessive sediment deposition.
Jeremi Hubert Naumczyk, Małgorzata Anna Kucharska, Joanna Agnieszka Ładyńska, Dominik Wojewódka
This study on tannery wastewater treatment showed that indirect electrooxidation by chlorine generated at a Ti/SnO2/PdO2/RuO2 (SPR) anode led to full ammonia removal and a decrease in chemical oxygen demand (COD) up to 58.9%. Summarized current efficiency of ammonia removal and apparent current efficiency of COD removal was very high and (up to 127.2%). Individual compounds present in raw and electrochemically treated wastewater and in synthetic tannin solutions were identified by GC-MS method. Dibutyl phthalate was determined in all samples of raw and/or wastewaters treated by electrooxidation and also in tannin solutions. For the wastewater sample D, current density of 1.0 A/dm2 values of adsorbable organically bound halogens were: 15.7, 19.8 and 12.9 mg/L after 15, 30 and 46 min, respectively. Additionally, a cost evaluation of this process was established. At a current density of 1.5 A/dm2, the energy consumption was in range from 78.2 to 171 kWh/kg of N–NH4+.
Jan Bogacki, Jarosław Zawadzki
Magnetic material may be added to proppant, as the magnetic marker allows to determine the range and efficiency of hydraulic fracturing. However, magnetic proppant may be also used in flowback fluid treatment and monitoring of environmental pollution. As a result of shale gas hydraulic fracturing, large volume of flowback fluid is created. Flow back fluid have similar properties to fracturing fluid, but it is potentially enriched with large amount of salts and organic compounds leached from shale. Magnetic proppant may serve as a heterogeneous catalyst during organic pollutants decomposition. Additionally, in case of leakage and consequently the fracturing fluid pollution, magnetic proppant is placed into the soil environment. It can be detected using magnetometric methods. This article discusses the above-mentioned issues based on the knowledge and experience of the authors and the literature review.
Michał Sobieraj, Marian Rosiński
Carbon dioxide, a natural refrigerant, is attracting attention as a direct solution to the legal restrictions on hydrofluorocarbon (HFC) refrigerants. The use of carbon dioxide as a refrigerant is limited by the triple point temperature of −56.5 °C. However, used along with a carrier fluid, carbon dioxide can provide refrigeration to temperatures lower than the triple point. A blend composed of carbon dioxide (R744) and isobutane (R600a) is experimentally studied. An experimental setup was designed, built, and verified in order to obtain the sublimation heat transfer coefficients of R744/R600a mixtures at temperatures lower than −56.5 °C. The test section comprises a horizontal copper tube with an inner diameter of 10 mm and length of 1 m. The tube is electrically heated by a copper wire heater wrapped uniformly around the tube. The tests were conducted with a novel refrigerant blend at heat fluxes from 3630 W m−2 to 8480 W m−2. The heat transfer coefficient decreases with increasing heat flux. Furthermore, a heat transfer coefficient calculation correlation has been developed.
Andrzej Białowiec, Karolina Sobieraj, Grzegorz Pilarski, Piotr Manczarski
There are insufficient data for the development of process design criteria for constructed wetlands systems based on submerged plants as a major treatment agent. The aim of the study was to evaluate the oxygen transfer capacity (OTC) of E. densa, in relation to wet plants’ mass (w.m.), and the influence of E. densa on the oxygen concentration and contaminants’ removal efficiency from municipal wastewater. The obtained oxygen concentration and temperature data allowed to calculate the OTC values (mg O2·L−1·h−1), which had been related to wet plants’ mass unit (mg O2·L−1·h−1·g w.m.−1). The efficiency of wastewater treatment was determined in relation to initial wastewater content in the mixture of wastewater and tap water (0%, 25%, 50%, and 100%) during 3 days of the experiment duration. The simulation of day and night conditions was done by artificial lighting. Before and after finishing the second experiment, the COD, Ntotal, and P-PO4 concentration were analyzed in wastewater solutions. The OTC ranged from 3.19 to 8.34 (mgO2·L−1·h−1·g w.m.−1), and the increase of OTC value was related to the increase of wet plant’s mass. The research showed that E. densa affected positively on the wastewater treatment efficiency, and the highest efficiency was achieved in 25% wastewater solution: 43.6% for COD, 52.9% for Ntotal, 14.9% for P-PO4.
Aniela Glinicka, Szymon Imiełowski
In aggressive environments structural steel components
of engineering structures may become affected by
corrosion. Even with corrosion protection, their critical load
capacity and stability are seriously affected by the consequences
of corrosion in aggressive environments due to impurities and
possible failures. In this paper a critical state analysis of corroded
struts is presented. The input data for the analysis was taken from
laboratory corrosion tests in which steel pipes of a few different
diameters were subjected to the attack of sulphuric and
hydrochloric acids and placed in salt spray tester. The loss of
material due to corrosion was determined and graphs, presenting
the loss of material as a function of pipe diameter and the
corrosion rate over time, were determined. The relative decrease
of the maximum elastic strain energy which can be stored in the
strut and the relative decrease of the critical load of elastic
buckling were calculated for a series of corroded pipes. The
curves of the relative change of the maximum elastic strain energy
and the relative change of critical load over the time of corrosion
progression were found to follow a similar path. For determining
the critical load for a given strut, boundary conditions are taken
into consideration. However, it is not necessary in the case of
maximum elastic strain energy, which makes it a more convenient
stability measure of the critical load capacity of strut.
The aim of this study was to find the most favourable shape of the front panel perforation shape, which would allow us to obtain the greatest cooling effect and – at the same time – be positively perceived by the people. The capacity of the personalized ventilation (PV) system to affect human thermal sensation, with different shapes of front panel perforation used, was analyzed.
Once the pilot study was conducted, it used a rectangular nozzle of front pattern size 320 mm × 125 mm and six different front patterns perforation shapes with round holes were tested. Operational parameters such as: airflow 20 l/s, supply air temperature at 24 °C or ambient temperature at 28 °C were invariable. The experiment consisted of a two-stage analysis of air jets characteristics and of tests in which people participated. Twenty-five male volunteers, at the age of 22–23 were engaged. They their assessed thermal sensation and completed relevant questionnaires.
On the basis of the results of the above study, differences in jet characteristics depending on the pattern shapes and their different impact on thermal sensation of the volunteers were demonstrated. The biggest cooling effect was obtained using front panels with small hole size (d = 5 mm). These perforations allowed us to obtain a more even air outflow from the entire panel. This ensured a broader airflow of lower velocity, reaching and affecting a larger area. With holes of larger size (d = 15 mm), air outflow occurred mainly through the central part, which produced narrow jets of higher velocity.
Jacek Wąsowski, Dariusz Kowalski, Beata Kowalska, Marian Kwietniewski, Małgorzata Zawilska
This research focused on a model setup fed with underground water pumped into a water supply network. The scope of the research included a long- and a short-term stagnation of water in the setup and a water flow of 0.1 m/s. The water supplied into the system gradually lost its corrosive properties and developed calcium carbonate precipitation capability. These processes indicated that cement components migrate from the lining into the water. Apart from the primary components, the presence of the following trace elements was found: iron (399.6 ppb), magnesium (17.8 ppm), zinc (26.9 ppb), barium (22.6 ppb), boron (21.6 ppb), sodium (10.8 ppm), gallium (2.1 ppb). At early stages of the operation, recorded quantities were not significant. Leaching of the trace elements from cement increased after water was chlorinated. In turn, the highest percent increases were observed in the case of zinc (217%), boron (19%) and gallium (12%), whereas the increase for sodium, iron, barium and magnesium in water was insignificant (reaching a few percent). A repeated analysis of samples of stagnant water in the setup showed that most of trace elements were below the detectability level. Final concentrations of all elements identified in the water after its contact with internal cement mortar lining were much lower than the limit values set out for drinking water
Sonam Wangchuk, Tobias Bolch, Jarosław Zawadzki
The majority of glacial lakes around the world are located in remote and hardly accessible regions. The use of remote sensing data is therefore of high importance to identify and assess their potential hazards. However, the persistence of cloud cover, particularly in high mountain areas such as the Himalayas, limits the temporal resolution of optical satellite data with which we can monitor potentially dangerous glacial lakes (PDGLs). The ability of Synthetic Aperture Radar (SAR) satellites to collect data, irrespective of weather and at day or night, facilitates monitoring of PDGLs by without compromising temporal resolution. In this study, we present a semi-automated approach, based on a radar signal intensity threshold between water and non-water feature classes followed by post-processing including elevations, slopes, vegetation and size thresholds, to delineate glacial lakes in Sentinel-1 SAR images in Bhutan Himalaya. We show the capability of our method to be used for delineating and monitoring glacial lakes in Bhutan Himalaya by comparing our results to 10 m resolution Sentinel-2 multispectral data, field survey data, meteorological data, and a time series of monthly images from January to December 2016 of two lakes. Sentinel-1 SAR data can, moreover, be used for detecting lake surface area changes and open water area variations, at temporal resolution of six days, providing substantial advantages over optical satellite data to continuously monitor PDGLs.
Jakub Pulka, Piotr Manczarski, Jacek A. Koziel, Andrzej Białowiec
We propose a ‘Waste to Carbon’ thermal transformation of sewage sludge (SS) via torrefaction to a valuable product (fuel) with a high content of carbon. One important, technological aspect to develop this concept is the determination of activation energy needed for torrefaction. Thus, this research aimed to evaluate the kinetics of SS torrefaction and determine the effects of process temperature on fuel properties of torrefied products (biochars). Torrefaction was performed using high ash content SS at six (200~300 °C) temperatures and 60 min residence (process) time. Mass loss during torrefaction ranged from 10~20%. The resulting activation energy for SS torrefaction was ~12.007 kJ·mol−1. Initial (unprocessed) SS higher heating value (HHV) was 13.5 MJ·kg−1. However, the increase of torrefaction temperature decreased HHV from 13.4 to 3.8 MJ·kg−1. Elemental analysis showed a significant decrease of the H/C ratio that occurred during torrefaction, while the O/C ratio fluctuated with much smaller differences. Although the activation energy was significantly lower compared with lignocellulosic materials, low-temperature SS torrefaction technology could be explored for further SS stabilization and utilization (e.g., dewatering and hygienization).
Marta Dudek, Kacper Świechowski, Piotr Manczarski, Jacek A. Koziel, Andrzej Białowiec
Biochar (BC) addition is a novel and promising method for biogas yield increase. Brewer’s spent grain (BSG) is an abundant organic waste with a large potential for biogas production. In this research, for the first time, we test the feasibility of increasing biogas yield and rate from BSG digestion by adding BC, which was produced from BSG via torrefaction (low-temperature pyrolysis). Furthermore, we explore the digestion of BSG with the presence BCs produced from BSG via torrefaction (low-temperature pyrolysis). The proposed approach creates two alternative waste-to-energy and waste-to-carbon type utilization pathways for BSG: (1) digestion of BSG waste to produce biogas and (2) torrefaction of BSG to produce BC used for digestion. Torrefaction extended the short utility lifetime of BSG waste turned into BC. BSG was digested in the presence of BC with BC to BSG + BC weight ratio from 0 to 50%. The study was conducted during 21 days under mesophilic conditions in n = 3 trials. The content of dry mass 17.6% in all variants was constant. The kinetics results for pure BSG (0% BC) were: reaction rate constant (k) 1.535 d−1, maximum production of biogas (B0) 92.3 dm3∙kg−1d.o.m. (d.o.m. = dry organic matter), and biogas production rate (r), 103.1 dm3∙kg−1d.o.m.∙d−1. his preliminary research showed that the highest (p < 0.05) r, 227 dm3∙kg−1d.o.m.∙d−1 was due to the 5% BC addition. This production rate was significantly higher (p < 0.05) compared with all other treatments (0, 1, 3, 8, 10, 20, 30, and 50% BC dose). Due to the high variability observed between replicates, no significant differences could be detected between all the assays amended with BC and the variant 0% BC. However, a significant decrease of B0 from 85.1 to 61.0 dm3∙kg−1d.o.m. in variants with the high biochar addition (20–50% BC) was observed in relation to 5% BC (122 dm3∙kg−1d.o.m.), suggesting that BC overdose inhibits biogas production from the BSG + BC mixture. The reaction rate constant (k) was not improved by BC, and the addition of 10% and 20% BC even decreased k relatively to the 0% variant. A significant decrease of k was also observed for the doses of 10%, 20%, and 30% when compared with the 5% BC (1.89 d−1) assays.
Andrzej Białowiec, Jacek A. Koziel, Piotr Manczarski
In this research, we explore for the first time the use of leaf stomatal conductance (gs) for phytotoxicity assessment. Plants respond to stress by regulating transpiration. Transpiration can be correlated with stomatal conductance when the water vapor pressure gradient for transpiration is constant. Thus, our working hypothesis was that the gs measurement could be a useful indicator of the effect of toxic compounds on plants. This lab-scale study aimed to test the measurement of gs as a phytotoxicity indicator. Our model plants were two common hydrophytes used in zero-effluent constructed wetlands for treating landfill leachate. The toxic influence of two types of leachate from old landfills (L1, L2) on common reed (Phragmites australis (Cav.) Trin. ex Steud.) and sweet flag (Acorus calamus L.) was tested. The gs measurements correlated well with plant response to treatments with six solutions (0 to 100%) of landfill leachate. Sweet flag showed higher tolerance to leachate solutions compared to common reed. The estimated lowest effective concentration (LOEC) causing the toxic effect values for these leachates were 3.94% of L1 and 5.76% of L2 in the case of reed, and 8.51% of L1 and 10.44% of L2 in the case of sweet flag. Leachate L1 was more toxic than L2. The leaf stomatal conductance measurement can be conducted in vivo and in the field. The proposed approach provides a useful parameter for indicating plant responses to the presence of toxic factors in the environment.
Agnieszka Tabernacka, Ewa Zborowska, Katarzyna Pogoda, Marcin Żołądek
A one-step technological system containing activated sludge fed with synthetic domestic wastewater was applied to treat waste air polluted with tetrachloroethene (PCE). In the first stage of the experiment, air passed through a bioscrubber; in the second and third stages, it passed through the bioreactor containing activated sludge and bacteria immobilised in oak chips. These bacteria are active in PCE biodegradation. Process efficiency in the final stage of the experiment was high; the elimination capacity was 0.23 g m−3 h−1 with the PCE mass loading rate of 0.58 g m−3 h−1. It has been shown that in the activated sludge bioreactor, bacteria adapted to PCE biodegradation and the wood chips protected microorganisms from the toxic effects of pollution. The dominant strains of bacteria immobilised in wood chips have been identified. Most of them were Gram-negative rods – Pseudomonas aeruginosa, Pseudomonas putida, Ralstonia pickettii and Ochrobactrum anthropii. Only one strain was Gram-positive and of cylindrical shape. The results of the study indicate the potential of immobilised bacteria capable of degrading chlorinated aliphatic hydrocarbons for the air and wastewater treatment. The low cost of the treatment process is an advantage.
Riverbed under the influence of natural and anthropogenic factors is constantly being transformed. The changes of the channel parameters related to natural phenomena are rarely dynamic. Contrarily it is in the case of human activity. The introduction of river engineering structures to the riverbed aims to quickly adapt the river to the requirements. If construction of such forms is designed taking account of natural conditions prevailing in the riverbed, then negative effects cannot be observed. The situation is different when the river’s characteristics were not considered in the design process. The article discusses the changes that the riverbed has undergone due to its intensive contraction at the ferry crossing at km 488 of Vistula, in Gassy. Current and archival aerial photographs were analyzed in terms of the transformation of the riverbed width, as well as the size of the mid-channel islands. The focus was concentrated on a section of the river 2 km above and 4 km below the ferry crossing. In particular, the parameters of the channel bar located directly below the narrowing and their change over the last decades were analyzed. Conclusions were drawn regarding the case study and recommendations for designing analogous solutions ensuing from the analysis were formulated.
Jan Bogacki, Piotr Marcinowski, Balkess El-Khozondar
One of the major environmental concerns associated with waste disposal is the large amount of generated landfill leachates (LL), which are considered a type of wastewater with a complex composition. There is an urgent need to find an effective LL treatment method. LL were subjected to pretreatment followed by the Fe0/H2O2 process. Pretreatment efficiency was coagulation at pH 6.0 >> coagulation at pH 9.0 > acidification at pH 3.0. Coagulation at pH 6.0 in an optimal Fe3+ dose of 1000 mg/L decreased total organic carbon (TOC) from the initial concentration of 1061 mg/L to 491 mg/L while acidification to pH 3.0 decreased TOC to 824 mg/L. After acidification, the Fe0/H2O2 process with 8000/9200 mg/L Fe0/H2O2 reagent doses decreased TOC to 499 mg/L after a processing time of 60 min. Performance of the Fe0/H2O2 process after coagulation at pH 6.0 for optimal Fe0/H2O2 8000/5540 mg/L reagent doses decreased TOC to 268 mg/L (75% TOC removal). Treatment of landfill leachates with combined process coagulation and Fe0/H2O2 also increased their susceptibility to biodegradation, expressed as the biochemical oxygen demand/chemical oxygen demand (BOD5/COD) ratio from 0.13 to 0.43, allowing LL to be considered as susceptible to biodegradation. Fe0/H2O2 process kinetics was described. A statistical analysis confirmed the obtained results. The proposed method can be successfully applied for LL treatment.
Wojciech Dąbrowski, Beata Karolinczak, Paweł Malinowski, Dariusz Boruszko
Reject water is a by-product of every municipal and agro-industrial wastewater treatment plant (WWTP) applying sewage sludge stabilization. It is usually returned without pre-treatment to the biological part of WWTP, having a negative impact on the nitrogen removal process. The current models of pollutants removal in constructed wetlands concern municipal and industrial wastewater, whereas there is no such model for reject water. In the presented study, the results of treatment of reject water from dairy WWTP in subsurface vertical flow (SS VF) and subsurface horizontal flow (SS HF) beds were presented. During a one-year research period, SS VF bed reached 50.7% efficiency of TN removal and 73.8% of NH4+-N, while SS HF bed effectiveness was at 41.4% and 62.0%, respectively. In the case of BOD5 (biochemical oxygen demand), COD (chemical oxygen demand), NH4+-N, and TN (total nitrogen), the P-k-C* model was applied. Multi-model nonlinear segmented regression analysis was performed. Final mathematical models with estimates of parameters determining the treatment effectiveness were obtained. Treatment efficiency increased up to the specific temperature, then it was constant. The results obtained in this work suggest that it may be possible to describe pollutant removal behavior using simplified models. In the case of TP (total phosphorus) removal, distribution tests along with a t-test were performed. All models predict better treatment efficiency in SS VF bed, except for TP.
Damian Zasina, Jarosław Zawadzki
Emission mapping distinctly facilitates observations and analysis of the anthropogenic CO2 emission impact, and the population data is frequently used for preparing spatial distributions of the CO2 emissions and also its precursors. Spatial analysis of the emissions or e.g. carbon footprint estimated for the spatially scattered sector such as residential combustion (IPCC sector 1A4bi) can be very hard to carry out, especially if in particular location considerable part of population is supplied with the heat from the district heating infrastructure. In this paper we propose the algorithm for spatial split between dwellings supplied from the district heating (CO2 emission in the sector 1A1a) and not supplied – emitting CO2 in the sector 1A4bi. Applying of the proposed algorithm changes distinctly the CO2 emission’s spatial distribution. The emissions are corrected only in grid cells which have non empty intersection with the district heating arteries. Validation of the model indicated 6% difference between the actual number of dwellers supplied from the heating system, and modelled. The authors suggest applicability of the algorithm for the CO2 emissions inventoried together with its precursors.
A. Rozmysłowska-Wojciechowska, E. Karwowska, S. Poźniak, T. Wojciechowski, L. Chlubny, A. Olszyna, W. Ziemkowska, A. M. Jastrzębska
The number of investigations regarding the application of 2D nanosheets of MXenes in different technological areas is growing rapidly. Different surface modifications of MXenes have been introduced to date in order to tailor their properties. As a result, surface-modified MXenes could be released in the environment from filtration membranes, adsorbents, or photocatalysts. On the other hand, assessment of their environmental impact is practically unexplored. In the present study, we examined how modification of the antimicrobial Ti3C2 MXene with ceramic oxide and noble metal nanoparticles affects its toxic behavior. The expanded 2D sheets of the Ti3C2 MXene phase were modified with Al2O3/Ag, SiO2/Ag, and SiO2/Pd nanoparticles using the sol–gel method and extensively characterized. The obtained 2D nanocomposite structures were characterized by antibacterial properties. The ecotoxicological assays considered green algae (Desmodesmus quadricauda) as well as two higher plants: sorghum (Sorghum saccharatum) and charlock (Sinapis alba). Our results revealed that obtained nanomaterials can cause both stimulating and inhibiting effects towards algae, and the ecotoxicity depended on the concentration and the type of modification. The study reveals the intriguing property of pristine Ti3C2 which highly stimulated green algae growth at low concentrations. It also shows that modification of pristine Ti3C2 MXene with different nanoparticles changes the ecotoxicological effects of the resulting nanocomposite 2D structures. We have also indicated nanocomposite structures that does not revealed the toxic effect on tested organisms i.e. the Ti3C2 MXene surface-modified with Al2O3/Ag was not phyto- and eco-toxic. This work helps with better understanding of the reactivity of surface-modified MXenes towards chosen organisms, giving more information concerning the potential impact of tested nanocomposites on the ecosystems.
Agnieszka Maria Jastrzębska, Ewa Karwowska, Tomasz Wojciechowski, Wanda Ziemkowska, Anita Rozmysłowska, Leszek Chlubny, Andrzej Olszyna
The expanded Ti2C and Ti3C2 MXene phases were synthesized from their parent Ti2AlC and Ti3AlC2 MAX phases using the same conditions of the classical acidic aluminum extraction method. The assumption for the study was that the expanded Ti2C and Ti3C2 MXenes are composed of the same atoms and if are synthesized from MAX phases using the same conditions of the classical acidic aluminum extraction method, the observed bio-effects can be related only to the changes in their structures. The scanning electron microscope investigations indicated that the expanded Ti2C and Ti3C2 sheets formed the specific network of slit-shaped nano-pores. The x-ray photoelectron spectroscopy for chemical analysis (ESCA-XPS) showed almost no difference in surface chemistry of Ti2C and Ti3C2 MXenes. The high-resolution transmission electron microscope investigations revealed, however, differences in atomic structure of the individual Ti2C and Ti3C2 sheets. Measured distance between Ti-C atomic layers in Ti2C was 9.76 Å and was larger by 0.53 Å in comparison with Ti3C2 (9.23 Å). Our investigations of bioactive properties toward model gram-negative Escherichia coli bacterial strain showed that the Ti2C MXene did not influence the viability of bacteria. Contrarily, the Ti3C2 MXene showed antibacterial properties. The results of the study indicate that the structure at the atomic scale may play a key role in the bioactivity of MXenes of the same chemical composition, but different stoichiometry, just like in case of Ti2C and Ti3C2.
Kwestarz Małgorzata, Osiadacz Andrzej J., Kotyński Łukasz
Leak detection in transmission pipelines is important for safe operation of pipelines. The probability of leaks may be occurred at any time and location, therefore pipeline leak detection systems play a key role in minimization of the occurrence of leaks probability and their impacts. During the operation of the network there are various accidents or intentional actions that lead to leaks of gas pipelines. For each network failure, a quick reaction is needed before it causes more damage. Methods that are used to detect such network failures are three-staged-: early identification of leakage, an accurate indication of itslocation and determine the amount of lost fluid. Methods for leak detection can be divided into two main groups: external methods (hardware) and internal methods (software). External leak detection methods require additional, often expensive equipment mounted on the network, or use systems that could display only local damage on the pipeline. The alternative are the internal methods which use available network measurements and signalling gas leakage signal based on the mathematical models of the gas flow. In this paper, a new method of leak detection based on a mathematical model of gas flow in a transient state has been proposed.
Barbara Błaszczak, Kamila Widziewicz-Rzońca, Natalia Zioła, Krzysztof Klejnowski, Katarzyna Juda-Rezler
Air pollution by particulate matter (PM) is recognized as a one of the most important environmental issue. A particular attention is being paid to fine PM fraction (PM2.5, PM1.0) due to its detrimental impact on human health and long-term persistence in the air. Presented work is an in-depth bibliometric study on the concentrations and chemical composition of PM2.5 among 27 rural and 38 urban/urban background stations dispersed across the Europe. Obtained results indicate that the chemical composition of PM2.5, in terms of mass concentrations and percentage contribution of main chemical constituents, is relatively different in various parts of Europe. Urban and urban background stations are typically characterized by higher share of total carbon (TC) in PM2.5, compared to rural background sites, mostly pronounced during the heating periods. The share of the secondary inorganic aerosol (SIA) is typically higher at rural background stations, especially in North-Western Europe. In general, the relative contribution of SIA in PM2.5 mass, both at rural and urban background stations, showed more or less pronounced seasonal variation, opposite to Polish measurement sites. Moreover, Poland stands out from the majority of the European stations by strong dominance of total carbon over secondary inorganic aerosol.