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Abstract

Along with the increase in popularity of the sewage sludge thermal treatment methods in Poland resulting from the implementation of European Union law, a management problem with ash, which is produced as a result of this process, appeared. The paper analyses the chemical composition and physical properties of fl y ash from thermal treatment of municipal sewage sludge in terms of its use in concrete technologies in relation to EN 450-1 Fly ash for concrete. Defi nition, specifi cations and conformity criteria (2012) and EN 197-1 Cement. Composition, specifi cations and conformity criteria for common cements (2011) standards. The tested material did not meet the requirements related to use of fl y ash for concrete production (chemical composition, low activity index, high water demand and fi neness), and as main and minor components for cement production. On the basis of the carried out research and analyses, it was found that the hardening slurry technology creates the greatest possibilities related to the management of fl y ash from thermal treatment of municipal sewage sludge.
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Abstract

Monitoring of activated sludge flocs may provide important information for effective operation and control of wastewater treatment. The research objective is to demonstrate methodology for activated sludge image processing aimed to describe morphological characteristics of activated sludge flocs. The proposed software- -based method was presented and verified by analysis of several activated sludge samples. The results show high efficiency of image segmentation and floc recognition of more than 94% floc components. The analysis of a series of 50 pictures gives rapid and reliable results and can be performed in an automatic or semiautomatic mode. Given inherent heterogeneity of activated sludge flocs, multiple and repeated sample images capture (processing of 50 pictures at a time, repeated at least 4 times ) is recommended.
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Abstract

One of the methods of sewage sludge disposal, which is based on its fertilizing properties, is its use in nature, e.g. in farming (if all the permissible standards are met). However, the sludge used for soil fertilization might also contain heavy metals, pathogenic microorganisms, thus causing contamination in soil foundation and deterioration of the conditions for development of indigenous organisms. Particular threat is posed by the existence of drug-resistant microorganisms in sewage sludge. This problem has not been researched in detail yet. The authors of the present study aimed to determine qualitative changes in drug-resistant microorganisms in sandy soil fertilized with selected sewage sludge. Sewage sludge after different types of drying process (natural and solar) was added to the degraded sandy soil. The effect of the methods of sewage sludge drying on concentration of drug-resistant microorganisms in soil fertilized with the sludge was analysed. The study demonstrated that sewage sludge dried naturally in drying beds pose threat to soil environment and, potentially, to people and animals which have contact with fertilized soils. In sandy soils fertilized with these types of sewage sludge, pathogenic forms which exhibit resistance to first-line antibiotics can be found.
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Abstract

The subject of the research is one of the largest World’s mine tailings disposal sites, i.e. Żelazny Most in the Legnica-Głogów Copper Mining District (south-western Poland), where flotation tailings are poured out after copper ore treatment. The protective hydraulic barrier made of 46 vertical drainage wells was characterized and evaluated in view of reduction of major contaminants (Cl, Na, SO4, Ca) migrating from the facility to its foreground. The efficiency of groundwater protection was determined on the basis of a new approach. In applied method the loads of characteristic and commonly recognizable compounds, i.e. salt (NaCl) and gypsum (CaSO4) were calculated, instead their chemical components. The temporal and spatial variability of captured main contaminants loads as well as its causes are discussed. The paper ends with the results of efficiency analyses of the barrier and with respect to the predicted increase in contaminant concentrations in the pulp poured out to the tailings site.
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Abstract

“Wartowice” tailings pond was closed in 1989, resulting in 232,4 ha tailings pile requiring reclamation. The major problem is heavy metals presence and poor nutrient conditions and physicochemical structure of soil which disturbs the plants development. In order to assess the real condition of studied area the complete biological characteristic has been done. The physicochemical conditions were assessed altogether with phytosociological, microbiological and toxicological studies of deposits. We recorded only 27 species of vascular plants belonging to 15 families on the tailings pond of which 5 belong to Rosaceae, 4 to Asteraceae and 3 to Poaceae and Saliceae. Species inhabiting the tailings depended on their dispersal capacity, metal tolerance and rhizome strategy. Microbiological analyses revealed the low number of bacteria and fungi on the tailings pond, apart from the small uplift area where the plants were indentified. Bacteria identified on the tailings pond were classified to 8 genera. The low number of bacteria suggests the lack of nutrients which affects the development of soil microflora. Toxicity tests showed that post-flotation sludge is not toxic to microorganisms because of its high pH. Some plants, such as lucerne could even influence positively the microorganisms development what has been proved in our studies. The tailings toxicity was higher towards producers, where Secale cereale appeared to be the most sensitive species. Amendment with topsoil from adjacent areas can influence positively the phytotoxic properties of tailings and enrich them into native seeds.
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Abstract

Water mint (Mentha aquatica L.) belongs to the arsenic tolerant plant species suitable for cultivation in Central European climate conditions. Therefore, its possible application for remediation of contaminated soil was investigated in pot and field experiments. Two M. aquatica plants of different origin, i) commercially market-available mint plants, and ii) plants habituated at the arsenic contaminated former mining area in southern Tuscany (Italy) were tested for their arsenic uptake, transformation, and speciation. The total arsenic concentrations in the experimental soils varied from 21 to 1573 mg As kg-1, the mobile fractions did not exceed 2% of total soil arsenic. The mint plants originating from the contaminated area were able to remove ~400 µg of arsenic per pot, whereas the commercial plant removed a significantly lower amount (~300 µg of arsenic per pot). Only arsenite and arsenate, but no organoarsenic compounds were identified in both stems and leaves. Arsenate was the predominant arsenic compound and reached up to 80% regardless of the origin of the mint plants. Although M. aquatica seems to be able to grow in contaminated soils without symptoms of phytotoxicity, its efficiency to remove arsenic from the soil is limited as can be demonstrated by total elimination of As from individual pots not exceeding 0.1%. Moreover, the application of plants originating from the contaminated site did not result in sufficient increase of potential phytoextraction efficiency of M. aquatica. Although not suitable for phytoextraction the M. aquatica plants can be used as vegetation cover of the contaminated soil at the former mining areas
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Abstract

Ammonia-oxidizing bacteria communities were evaluated in a completely mixed, laboratory scale membrane reactor (MBR) working under anoxic conditions for 5 months. The microorganisms in activated sludge were fed a synthetic medium containing 66-150 mg NH4 +-N/l. The age of the activated sludge in MBR was 50 days and the hydraulic retention time (HRT) was 3.3 days. The estimation of the diversity and complexity of the AOB community together with the identification of the dominant bacteria in the activated sludge under anoxic conditions were performed using denaturing gradient gel electrophoresis (DGGE) and DNA sequencing. Molecular analysis of the microbial community carried out with two microbial molecular markers, 16S rRNA gene and amoA gene, suggested that nitrification was led by a Nitrosomonas-like species. In the biocenosis of the investigated bioreactor, oxygen was the crucial selective parameter. The results obtained in this work showed that amoA gene research is more suitable to study the stability and effectiveness of ammonia oxidation. This information emphasizes the necessity of the usage of molecular markers based on functional genes instead of ribosomal ones in order to present the actual state of the process performed in bioreactors. It was also stated that Nitrosomonas -like bacteria are able to perform nitritation even in anoxic environment, that is probably the reason why these bacteria are the most common AOB in different bioreactors.
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Abstract

Treatment of leachate from an exploited since 2004 landfill by using two methods of advanced oxidation processes was performed. Fenton’s reagent with two different doses of hydrogen peroxide and iron and UV/H2O2 process was applied. The removal efficiency of biochemically oxidizable organic compounds (BOD5), chemically oxidizable compounds using potassium dichromate (CODCr) and nutrient (nitrogen and phosphorus) was examined. Studies have shown that the greatest degree of organic compounds removal expressed as a BOD5 index and CODCr index were obtained when Fenton’s reagent with greater dose of hydrogen peroxide was used - efficiency was respectively 72.0% and 69.8%. Moreover, in this case there was observed an increase in the value of ratio of BOD5/CODCr in treated leachate in comparison with raw leachate. Application of Fenton’s reagent for leachate treatment also allowed for more effective removal of nutrients in comparison with the UV/H2O2 process.
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Abstract

Exploitation of lignite within the area of Muskau Arch, carried out from the mid-nineteenth century, contributed to the transformation of the natural environment and changes in water regime. In the post-mining subsidences pit lakes were formed. The chemical composition of waters is a consequence of the intensive weathering of pyrite (FeS2), which is present in Miocene lignite-bearing rock forming the embankments of the lakes. This process leads to the formation of Acid Mine Drainage (AMD) and finally acidification of lake waters. This paper presents results of the identification of hydrogeochemical processes affecting the chemistry of waters from these reservoirs carried out using the speciation and statistical (cluster and factor) analyses. Cluster analysis allowed to separate from the analyzed group of anthropogenic reservoirs 7 subgroups characterized by a similar chemical composition of waters. The major processes affecting the chemistry of waters were identified and interpreted with help of factor and speciation analysis of two major parameters (iron and sulfur).
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Abstract

This paper deals with wastewater treatment systems placed in motorway service areas (MSAs). In the years 2008-2009 eight of such facilities installed on the stretch of the A2 motorway between Poznań and Nowy Tomyśl were examined and analyzed. The system consists of a septic tank, a submerged aerated biofilter and an outflow filter. The volume of traffic on the highway was analyzed, the amount of water use was measured and peak factors were calculated. On this basis it was concluded that the inflows to the wastewater treatment systems in many cases exceeded the nominal design values. Based on the analysis of effluent quality it was found that the effects of plant operation in large part did not meet the requirements. It was found that the bioreactor aeration system and the design of the suspension separator (outflow filter) should be modified. One of the solutions was to use the soil-reed bed for wastewater treatment. The treatment of wastewater from the MSAs is a task that must take into account the unusual character of these facilities and the atypical quality of the effluent.
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Abstract

FA discharged from the wastewater treatment plant were extracted from purifi ed effl uents for the quantitative and qualitative analysis. The treated sewage from municipal treatment plants was acidifi ed to pH <2 and extracted with ion exchange resins in a laboratory column. After desorption with NH4 OH, the fulvic acids were condensed under vacuum and tested for mass performance, UV-VIS light spectra, IR absorption spectra, elementary composition and other elements. Their structure was analysed and compared to FA present in surface waters and in sewage treated in other sewage treatment plants based on the authors’ own research and the literature data. The concentration of FA in the treated sewage was 5.2 mg/L. There is a high interdependence between the IR spectrum analysis in the visible light and the elementary composition of FA extracted from different environments, confi rming the conclusions pertaining to the structure and properties of the acids being tested. The longer sewage is subjected to a biological treatment process, the greater the degree of aromatic condensation and humus maturity of the FA contained within it. FA contained in the sewage treated in the three biological sewage treatment plants have the ratio A2 /A3 (the ratio of the absorbance of light with the wavelength of 250 and 300 nm) equal to the value 1.7. There is a high interdependence between the IR spectrum analysis in the visible light and the elementary composition of FA extracted from different environments, confi rming the conclusions pertaining to the structure and properties of the acids being tested.
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Abstract

Sediments of two dam reservoirs in SE Poland, Zalew Zemborzycki (ZZ) and Brody Iłżeckie (BI) were studied. The sediments from both reservoirs were sampled in the transects perpendicular to the shoreline, at the river inflow and the frontal dam. The total concentration of Mn, Zn, Pb, Cd, Cu, Cr and Ni was determined by ICP-EAS method after the sample digestion in the mixture of concentrated HNO3 and HClO4 acids. The statistical analyses: value intervals, mean values, variation coefficient, the median and the skewed distribution were performed. To estimate differences between the means for transects, Tukey’s test was applied with least significant difference (LSD) determination. The maps of the metal spatial distribution were drawn and sediment quality according to the geochemical and ecotoxicological criteria evaluated. Differences between the reservoirs in terms of heavy metals concentration in bottom sediments, and regularities in their spatial distribution were found. In the ZZ sediments the concentration was at the level of geochemical background (Zn, Cr), slightly (Cd, Cu, Ni) or moderately (Pb) contaminated sediments. The metal concentration in the sediments of the BI was up to eight times higher as compared to the ZZ. Moreover, sediments from the BI reservoir showed a greater variability of metal concentration than those from ZZ, which resulted from the dredging operation performed in the part of the reservoir. Metal concentration in sediments of the dredged part was ca. 2–5 times lower than in the undredged one, which indicates that after the dredging operation, accumulation of these metals was slight. The concentrations of Zn, Pb and Cd from the undredged part of BI were at the level of contaminated sediments and exceeded the probable effects level (PEL). In the ZZ, the greatest accumulation of metals occurred in the upper part of the reservoir and at the frontal dam, and the lowest in the middle part of the reservoir. In BI, the lower outflow of water in this reservoir caused a lower metal concentration in the sediments at the frontal dam, as compared with the other sediments in the undredged part of the reservoir. The results indicate that in small and shallow reservoirs, areas of accumulation of heavy metals depend on such factors as a parent river current, reservoir depth, water waving, reservoir shape (narrowing, coves/bays), and type of water outflow.
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Abstract

The aim of this work was to determine the effect of various cadmium and copper concentrations on the activated sludge dehydrogenase activity. The investigations were carried out in six aerated chambers with activated sludge, volume of 1L each, by the continuous culture method (one control chamber, not contaminated with heavy metals and five with 0.5; 1; 2; 4; 8 mg L-1 Cu+2 and 0.1; 0.3; 0.9; 2.7; 8.1 mg L-1 Cd2+). Cadmium sulfate and copper sulfate as a source of heavy metals were used. The concentrations of these metal ions, causing 50% dehydrogenase activity inhibition were determined. The particular attention was paid to the toxic effect of metal ions, as well as the variations of the microbial respiration activity proceeded during toxins exposition. The investigation showed that even the lowest concentration of the investigated metal ions caused significant changes of the activated sludge dehydrogenases activity. Copper ions showed to be more toxic than cadmium ions.
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Abstract

The most common chemical’s spills in typical transportation accidents are those with petroleum products such as diesel fuel, the consequence of which is an extensive pollution of the soil. In order to plan properly fuel recovery from the soil, it is important to gain information about the soil depth which may be affected by pollutant and to predict the pollutant concentration in different soil layers. This study deals with the impact of basic atmospheric conditions, i.e. air temperature and humidity on the diesel fuel migration through the soil. The diesel fuel was spilled into columns (L = 30 cm; D = 4.6 cm) filled with sandy and clay soil samples, and its concentrations at various depths were measured after 11 days under various air temperature (20 and 40°C) and relative humidity (30–100%) conditions. The effects observed were explained by understanding physical processes, such as fuel evaporation, diffusion and adsorption on soil grains. The increase in temperature results in higher fuel evaporation loss and its faster vertical migration. The relative humidity effect is less pronounced but more complex, and it depends much on the soil type.
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Abstract

According to data of the Central Statistical Office, the amount of sludge produced in municipal wastewater treatment plants in 2010 amounted to 526000 Mg d.m. The forecast of municipal sewage sludge amount in 2015 according to KPGO2014 will reach 642400 Mg d.m. and is expected to increase in subsequent years. Significant amounts of sludge will create problems due to its utilization. In order to solve this problem the use of thermal methods for sludge utilization is expected. According to the National Waste Management Plan nearly 30% of sewage sludge mass should be thermally utilized by 2022. The article presents the results of co-combustion of coal and municipal sewage sludge in a bubbling fluidized bed boiler made by SEFAKO and located in the Municipal Heating Company in Morag. Four tests of hard coal and sewage sludge co-combustion have been conducted. Boiler performance, emissions and ash quality were investigated.
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Abstract

The research aimed to use chemical, geochemical, and ecotoxicity indices to assess the heavy metals content in soils with different degrees of exposure to human pressure. The research was conducted in southern Poland, in the Malopolska (Little Poland) province. All metal contents exceeded geochemical background levels. The highest values of the Igeo index were found for cadmium and were 10.05 (grasslands), 9.31 (forest), and 5.54 (arable lands), indicating extreme soil pollution (class 6) with this metal. Mean integrated pollution index (IPI) values, depending on the kind of use, amounted to 3.4 for arable lands, 4.9 for forests, and 6.6 for grasslands. These values are indicative of a high level of soil pollution in arable lands and an extremely high level of soil pollution in grasslands and forests. Depending on the type of soil use, Vibrio fischeri luminescence inhibition was from -33 to 59% (arable lands), from -48 to 78% (grasslands), and from 0 to 88% (forest). Significantly the highest toxicity was found in soils collected from forest grounds.
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Abstract

The aim of the study was to analyze and assess the possibility of using a two-stage filtration system with ceramic membranes: a 3-tube module with 1.0 kDa cut-off (1st stage) and a one-tube module with 0.45 kDa cut-off (2nd stage) for treating effluent water from a juvenile African catfish aquaculture. The study revealed that during the 1st filtration stage of the effluent water, the highest degrees of retention were obtained with respect to: suspended solids SS (rejection coefficient RI=100%), turbidity (RI=99.40%), total iron (RI=89.20%), BOD5 (RI=76.0%), nitrite nitrogen (RI=62.30%), and CODCr (RI=41.74%). The 2nd filtration stage resulted in a lower reduction degree of the tested indicators in comparison to the 1st filtration stage. At the 2nd stage, the highest values of the rejection coefficient were noted in for the total iron content (RIV=100%), CODCr (RIV=59.52%; RV=64.28%, RVI=63.49%) and turbidity (RIV and RV = 45.0%, RVI=50.0%). The obtained results indicate that ceramic membranes (with 1.0 and 0.45 kDa cut-offs) may be used in recirculation aquaculture systems as one of the stages of effluent water treatment.
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Abstract

High intake of over-the-counter, non-steroidal anti-inflammatory drugs, such as ibuprofen, has resulted in their presence in wastewaters and surface waters. The potentially harmful effect of ibuprofen present in the waters has led to a search for new methods of drugs’ removal from the environment. One of the most important technological and economical solutions comprises microbiological degradation of these resistant pollutants. Searching for new strains able to degrade ibuprofen could be one of the answers for increasing the detection of pharmaceuticals in the waters. In this study, the ability of bacterial strain Bacillus thuringiensis B1(2015b) to remove ibuprofen is described. Bacteria were cultured in both monosubstrate and cometabolic systems with 1, 3, 5, 7 and 9 mg L-1 ibuprofen and 1 g L-1 glucose as a carbon source. Bacillus thuringiensis B1(2015b) removed ibuprofen up to 9 mg L-1 in 232 hours in the monosubstrate culture, whereas in the cometabolic culture the removal of the drug was over 6 times faster. That is why the examined strain could be used to enhance the bioremediation of ibuprofen.
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Abstract

In this work, response surface optimization strategy was employed to enhance the biodegradation process of fresh palm oil mill effluent (POME) by Aspergillus niger and Trichoderma virens. A central composite design (CCD) combined with response surface methodology (RSM) were employed to study the effects of three independent variables: inoculum size (%), agitation rate (rpm) and temperature (°C) on the biodegradation processes and production of biosolids enriched with fungal biomass protein. The results achieved using A. niger were compared to those obtained using T. virens. The optimal conditions for the biodegradation processes in terms of total suspended solids (TSS), turbidity, chemical oxygen demand (COD), specific resistance to filtration (SRF) and production of biosolids enriched with fungal biomass protein in fresh POME treated with A. niger and T. virens have been predicted by multiple response optimization and verified experimentally at 19% (v/v) inoculum size, 100 rpm, 30.2°C and 5% (v/v) inoculum size, 100 rpm, 33.3°C respectively. As disclosed by ANOVA and response surface plots, the effects of inoculum size and agitation rate on fresh POME treatment process by both fungal strains were significant.
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Abstract

The presented results of research on the effectiveness of enzymatic hydrolysis of lignocellulosic waste, depending on their initial depolymerisation in alkaline medium were considered in the context of the possibility of their further use in the fermentation media focused on the recovery of energy in the form of molecular hydrogen. The aim of this study was to determine the appropriate dose and concentration of a chemical reagent, whose efficiency would be high enough to cause decomposition of the complex, but without an excessive production of by-products which could adversely affect the progress and effectiveness of the enzymatic hydrolysis and fermentation. The effect of treatment on physical-chemical changes of homogenates’ properties such as pH, COD, the concentration of monosaccharide and total sugars and the concentration of total suspended solids and volatile suspended solids was determined. The enzymatic decomposition of lignocellulosic complex was repeatedly more efficient if the sample homogenates were subjected to an initial exposure to NaOH. The degree of conversion of complex sugars into simple sugars during enzymatic hydrolysis of homogenates pre-alkalized to pH 11.5 and 12.0 was 83.3 and 84.2% respectively, which should be sufficient for efficient hydrogen fermentation process.
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Abstract

A laboratory study was performed to study the effects of various operating factors, viz. adsorbent dose, contact time, solution pH, stirring speed, initial concentration and temperature on the adsorption of triphenyltin chloride (TPT) onto coal fly ash supported nZnO (CFAZ). The adsorption capacity increases with increase in the adsorbent amount, contact time, pH, stirring speed and initial TPT concentration, and decrease with increase in the solution temperature. The adsorption data have been analyzed by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) adsorption models to determine the mechanistic parameters associated with the adsorption process while the kinetic data were analyzed by pseudo first-order, pseudo second-order, Elovich, fractional power and intraparticle diffusivity kinetic models. The thermodynamic parameters of the process were also determined. The results of this study show that 0.5 g of CFAZ was able to remove up to 99.60% of TPT from contaminated natural seawater at 60 min contact time, stirring speed of 200 rpm and at a pH of 8. It was also found that the equilibrium and kinetic data fitted better to Freundlich and pseudo second-order models, respectively. It can therefore be concluded that CFAZ can be effectively used for shipyard process wastewater treatment
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Abstract

Cd and Pb concentrations were measured in water, sediment and plant organs collected from selective sites located along the Bogdanka river (Poznań, Poland) in the 2012 growing season. The aim of the investigations was to monitor changes in heavy metal (HM) concentrations in different media over the periods, as well as to evaluate potential of two littoral plants, Phragmites australis and Typha angustifolia, for phytoremediation under natural conditions. Investigations revealed differences in HM concentrations in water and sediments. Higher values were observed in sediments than in water. The decrease in concentrations of both HMs in sediments was noted in two of the three selected water reservoirs during growing seasons, which suggests the possibility of their adsorption and accumulation by aquatic plants. Both investigated plant species accumulated ample amount of Cd and Pb in underground and aboveground plant tissues, however T. angustifolia revealed higher Cd translocation potential than P. australis. The latter revealed higher Pb accumulation in two lakes. Moreover, the translocation ratio was usually higher in spring, especially for Pb, in both plant species. Increasing level of pollution load index in sediment along the Bogdanka watercourse indicates accumulation of measured HMs.
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Abstract

The article describes problems related to intensification of energy production at a sewage treatment plant. The authors analyze anaerobic co-digestion of sludge from a water treatment plant and sewage treatment plant. The authors proposed a methodology of the research and analyzed the preliminary results, which showed that co-digestion of sewage and water sludge enhanced biogas production. The authors hope that the results of the study will provide a basis for development of methodology for sludge control and disposal.
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Abstract

Over the two-year study (2008–2009) we monitored the influence of integrated and conventional production systems on microbiological activity in soil and strawberry yield. The experiment also involved fertilizers applied in three variants of treatment. The studied parameters were monitored over 2008 and 2009 by determining the total number of soil microorganisms, the number of ammonifying bacteria and the strawberry yield. The results of the study suggest the pronounced inhibitory effect of insecticides on number of studied microorganism groups in all three conventionally treated variants, over the both years of study, which further infers negligible stimulative influence of strawberry plants on yield.
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