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Abstract

The subject of investigations was the fragment of low peatland complex located close to Miękinia, about 30 km from Wrocław. Within the range of the examined area of peat bog complex there can be distinguished three parts differing in their utilization and composition of species, namely: 1/ the area degraded by the attempt to afforest it with alder trees Alnus glutinosa (L.) Gaertner, 2/ occasionally used bog hay meadow and 3/ typical peat forming phytocenosis. Total number of determined species, belonging to 11 phytosociological classes, ranged 77, out of which more than a half constitute representatives of Molinio-Arrhenatheretea class. As far as a non-afforested area was concerned, there were determined 5 phytocenosis, including 4 classified as peat forming ones and one typical for post-bog meadows (Alopecuretum pratensis). The afforested area featured herbaceous plant composition which indicated that the area with Alopecuretum pratensis phytocenosis had been degraded. Analysis of environmental requirements, done with the use of ecological numbers, proved that prevailing number of species characterize similar requirements. It was mainly afforested part to feature taxons of broader ecological scale, e.g. Polygonum bistora L., Carex hirta L. and Plantago lanceolata L. The afforested area was purchased by a private person, therefore it can be assumed that the reason for such a way of peatlands utilization was obtaining EU subsidies at minimum work effort. A higher financial profit, however, would have been made by the owner if he had maintained a bog area as an extensive meadow.
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Abstract

A number of inorganic compounds, including anions such as nitrate(V), chlorate(VII), bromate (V), arsenate(III) and (V), borate and fluoride as well as metals forming anions under certain conditions, have been found in potentially harmful concentrations in numerous water sources. The maximum allowed levels of these compounds in drinking water set by the WHO and a number of countries are very low (in the range of µg/l to a few mg/l), thus the majority of them can be referred to as charged micropollutants. Several common treatment technologies which are nowadays used for removal of inorganic contaminants from natural water supplies, represent serious exploitation problems. Membrane processes such as reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF) and microfiltration (MF) in hybrid systems, Donnan dialysis (DD) and electrodialysis (ED) as well as membrane bioreactors (MBR), if properly selected, offer the advantage of producing high quality drinking water without inorganic anions. I
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Abstract

This work presents the results of a study whose aim was to determine the influence of algal blooms on precipitation of heavy metals. The scope of the study covered culture of a mixed population made up of Scenedesmus and Pseudokirchneriella algae in experimental conditions and initiating a metal biosorption process with the use of culture biomass by administering ions of Zn(II) and Ni(II). The process was controlled by assessing the level of biosorption of metals entered at a one-off basis in the form of Zn(II) and Ni(II) salts or in the form of mixture of both ions, in comparison to the control sample, at different exposure times (2 hours and 24 hours). The presence of metals was determined both in the biomass and in the culture medium. The presented results of the study confirm the effectiveness of Chlorophyta in the process of zinc and nickel biosorption. A phenomenon of competitiveness between the metals was observed when they were administered at the same time.
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Abstract

In Poland, according to the statistical data, about 40% of sewage sludges originating from wastewater treatment plants are applied in the agriculture. The mentioned way of application of sewage sludges causes the hazard of contamination of environment with carcinogenic compounds due to the presence of some organic micropollutants, such as polycyclic aromatic hydrocarbons (PAHs). The proposal of changing UE Directive obligates control of organic pollutants (PAHs and others) in sewage sludges applied in the agriculture. The aim of the investigations was to estimate the persistence of PAHs under stored conditions by determining half-life of their decomposition. Eight carcinogenic PAHs, among 16 compounds, listed by EPA were determined. In this study, the quantity changes in the concentration of PAHs in stored sewage sludges were investigated. Sewage sludges were stored under aerobic conditions for 16 weeks. At the same time the sewage sludges with sodium azide added, in order to deactivate the microorganisms (abiotic samples), were also stored. Gas chromatography-mass spectrometry was used to qualify and quantify PAHs in 2- and 4-week intervals. Sewage sludges were taken two fold from a municipal wastewater treatment plant. In practice, the sewage sludges are directed to the disposal site. The initial concentration of 16 PAHs in sewage sludge was equal to 582 μg/kg.d.m. The changes in the concentration of PAHs corresponded to exponential function. Values of correlation coefficients indicate a significant dependence of PAHs persistence and concentration on time exposition. Under experimental conditions the half-lives of individual compounds were diversed. In biotic samples half-life of hydrocarbons was in the range of 17 to 126 days. Half-life of PAHs in abiotic sewage sludges was in the range of 32 to 2048 days. The most persistent were benzo(a)pyrene and benzo(b) fluoranthene, respectively. A significant dependence of PAHs' decrease on the presence of microorganisms in sewage sludges after 10 weeks of storage was found.
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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

The paper describes the effectiveness of mycoestrogen removal in an integrated ozonation - nanofiltration system for water treatment. The results were compared to those obtained for ozonation and nanofiltration carried out as single processes. It has been found that the effectiveness of mycoestrogen removal in the integrated system was higher than that observed for single ozonation. During ozonation, the removal of micropollutants was affected by the dose of an oxidizing agent and type of treated water. As far as nanofiltration is concerned, its effectiveness both in the integrated system and as a single process was similar. Nevertheless, it is advisable to precede nanofiltration with ozonation because of membrane efficiency.
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Abstract

Zinc plant residue is a hazardous waste which contains high quantity of nickel and other valuable metals. Process parameters such as reaction time, acid concentration, solid-liquid ratio, particle size, stirring speed and temperature for nickel extraction from this waste were optimized using factorial design. Main effects and their interactions were obtained by the analysis of variance ANOVA. Empirical regression model was obtained and used to predict nickel extraction with satisfactory results and to describe the relationship between the predicted results and the experiment results. The important parameters for maximizing nickel extraction were identifi ed to be a leaching time solid-liquid ratio and acid concentration. It was found that above 90% of nickel could be extracted in optimum conditions.
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Abstract

The study was conducted on the Biała Lądecka River which is a mountain river. It is similar to many European mountain rivers in terms of hydromorphology and catchment management. The aim of this study was to determine the bioconcentration factors of heavy metals (Pb, Cd, Hg, Ni, Cr, Cu and Zn) in Ranunculus aquatile (L.) Dumort., Fontinalis antipyretica (L. ex Hedw.), and Lemanea fluviatilis (L.) C.Ag. The content of metals in water, sediment, and submerged plants was determined. The metal concentrations in plants can be arranged as follows: Hg < Cd < Cr < Ni < Cu < Pb <Zn. The highest concentrations of Hg, Ni, Cr, and Cu were observed in F. antipyretica, but the highest concentrations of Pb, Cd, and Zn were in R. aquatile. L. fluviatilis always contained the least amounts of heavy metals. Bioconcentration factors (BCFs) were lowest in L. fluviatilis and highest in F. antipyretica. Among the analyzed metals, plants accumulated the highest amount of Zn, and the least of Hg. The BCFs for Zn were from 24111 (in L. fluviatilis) to 97574 (in R. aquatile), and BCFs for Hg were from 29 (in L. fluviatilis) to 226 (in F. antipyretica).
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Abstract

Aluminium is one of the main soil components. Usually it is a part of non-toxic aluminosilicates but in low pH values its mobility is higher and - especially in monomeric form is toxic for plants. Selenium is an essential element necessary for animals and humans. Its compounds have anticancer and anti mutagenic character. However, its high uptake from environment, e.g. with food or water could lead to various diseases including embryonic deformity, decreased hatchling survival and death to aquatic organisms. Soil contamination with aluminium leads to disturbances in plant growth as a result of low calcium and magnesium uptake. High concentrations of selenium lead to its accumulation in plant tissues what is the beginning of selenium fate in food chain. In this work a cultivated layer of soils located near five industry plants in the town of Opole (southern Poland) were investigated. Aluminium and selenium content in soils is an effect of two factors: its natural occurrence in rocks (natural content) and human activity - especially chemicals from agriculture, industrial and transport pollutants. Aluminium was determined in the range of 3440 to 14804 mg/kg d.w. Obtained results of selenium concentration covered the range from 27.1 to 958.1 μg/kg d.w. These results are slightly higher than concentrations noted in natural or non-polluted soils, but still low. These amounts of selenium could have more positive than negative effects. Aluminium and selenium concentrations were discussed concurrently with base soils parameters, such as pH, EC and granulometric fractions composition.
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Abstract

A forecast of the negative impact exerted on the environment by selected trace elements in “Bełchatów” Power Plant has been prepared on the basis of the results of investigations into these elements’ distribution carried out as part of earlier research on coal from “Bełchatów” Field and the data on updated analyses of the content of these elements in 55 brown coal samples from test boreholes. Work in “Bełchatów” Power Plant, which is supplied with coal from “Szczerców” Field, will be accompanied by trace elements transfer. On the basis of the conducted investigations it has been found that the biosphere is most threatened by mercury emissions. As shown by the presented results of analyses and calculations, the emissions of mercury in “Bełchatów” Power Plant are low. Mercury is accumulated chiefl y in gypsum produced in the FGD plant. The content of mercury in slag and ash is low.
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Abstract

Trace elements contained in coal escape with flue gas from energy sources into the air or move towards other components of the environment with by-products captured in electrofilters (EF) and flue gas desulphurisation (FGD) plants. The existing knowledge about the distribution of frequently dangerous trace elements contained in these products is insufficient. Studies were therefore undertaken in selected power plants to investigate the distribution of trace elements in coal, slag, as well as dust containment and flue gas desulphurisation products, such as fly ash captured in dust collectors, desulphurisation gypsum and semi-dry scrubbing FGD products. Using the technique of flame atomic absorption spectrometry (F-AAS) and mercury analyser, the following were determined in the research material samples: Cr, Cu, Hg, Mn, Ni, Pb and Zn. The studies have a reconnaissance character. The authors have presented the results of determinations for selected trace elements in samples taken at Jaworzno III and Siersza Power Plants, which burn hard coal, and in Bełchatów Power Plant, burning brown coal. A balance of the examined trace elements in a stream of coal fed into the boiler and in streams of waste and products carried away from the plant was prepared. The balance based on the results of analyses from Bełchatów Power Plant was considered encouraging enough to undertake further investigations. The research confirmed that due to the distribution in the process of coal combustion and flue gas treatment, a dominant part of particular trace elements’ stream moves with solid waste and products, while air emission is marginal. Attention was paid to the importance of research preparation, the manner of sample taking and selection of analytical methods.
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Abstract

The paper presents the investigations aimed at the determination of the effect of time and wavelength of ultrasound field on the value of capillary suction time (CST), sludge thickening and dry matter of the excess sludge subjected to the process of stabilization. The investigations were carried out on the excess sludge which comes from communal waste treatment plant. The sludge was exposed to ultrasound field, using ultrasound generator with power of 1500 W, frequency of 20 kHz and amplitude 39.42 μm (which corresponded to the amplitude of 100%). Sonication of the sludge was carried out for different amplitudes and sonication times. The non-conditioned sludge and the sludge initially conditioned with ultrasound field were subjected to the process of stabilization in laboratory flasks (V = 0.5 dm3) for the period of 10 days. On each day, sludge thickening and dewatering capacities were determined. The sludge subjected to the effect of ultrasound field exhibited elevated levels of CST. However, the sonication time had positive effect on the increase in the degree of thickening for each of the amplitudes studied. Also, the process of stabilization positively affected final thickening and dewatering of the sludge.
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Abstract

The factor which essentially affects sludge biodegradation rate is the degree of fluidization of insoluble organic polymers to the solved form, which is a precondition for availability of nutrients for microorganisms. The phases which substantially limit the rate of anaerobic decomposition include hydrolytic and methanogenic phase. Subjecting excess sludge to the process of initial disintegration substantially affects the effectiveness of the process of anaerobic stabilization. As a result of intensification of the process of hydrolysis, which manifests itself in the increase in the value and rate of generating volatile fatty acids (VFA), elongation of methanogenic phase of the process and increase in the degree of fermentation of modified sludge can be observed. Use of initial treatment of sewage sludge i.e. thermal disintegration is aimed at breaking microorganisms' cells and release of intracellular organic matter to the liquid phase. As a result of thermal hydrolysis in the sludge, the volatile fatty acids (VFA) are generated as early as at the stage of the process of conditioning. The obtained value of VFA determines the course of biological hydrolysis which is the first phase of anaerobic stabilization. The aim of the present study was to determine the effect of thermal disintegration of excess sludge on the effectiveness of the process of hydrolysis in anaerobic stabilization i.e. the rate of production of volatile fatty acids, changes in the level of chemical oxygen demand (COD) and increase in the degree of reduction in organic matter. During the first stage of the investigations, the most favourable conditions of thermal disintegration of excess sludge were identified using the temperatures of 50°C, 70°C, 90°C and heating times of 1.5 h - 6 h. The sludge was placed in laboratory flasks secured with a glass plug with liquid-column gauge and subjected to thermal treatment in water bath with shaker option. Another stage involved 8-day process of anaerobic stabilization of raw and thermally disintegrated excess sludge. Stabilization was carried out in mesophilic temperature regime i.e. at 37°C, under periodical conditions. In the case of the process of anaerobic stabilization of thermally disintegrated excess sludge at the temperature of 50°C and heating time of 6 h (mixture B) and 70°C and heating time of 4.5% (mixture C), the degree of fermentation of 30.67% and 33.63%, respectively, was obtained. For the studied sludge, i.e. mixture B and mixture C, maximal level of volatile fatty acids i.e. 874.29 mg CH3COOH/dm3 and 1131.43 mg CH3COOH/dm3 was found on the 2nd day of the process. The maximal obtained value of VFA was correlated on this day with maximal COD level, which was 1344 mg O2/dm3 for mixture B and 1778 mg O2/dm3 for mixture C.
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Abstract

The removal of benzene (B) and toluene (T) from aqueous solution by multi walled, single walled, and hybrid carbon nanotubes (MWCNTs, SWCNTs, and HCNTs) was evaluated for a nanomaterial dose of 1 g/l, concentration of 10-100 mg/l, and pH 7. The equilibrium amount removed by SWCNTs (B: 9.98 mg/g and T: 9.96 mg/g) was higher than for MWCNTs and HCNTs. Toluene has a higher adsorption tendency on CNTs than benzene, which is related to the increasing water solubility and the decreasing molecular weight of the compounds. The SWCNTs performed better for B and T sorption than the MWCNTs and HCNTs. Isotherms study based on isofit program indicate that the Generalized Langmuir-Freundlich (GLF) isotherm expression provides the best fit for benzene sorption, and that Brunauer-Emmett-Teller (BET) isotherm is the best fit for toluene adsorption by SWCNT. SWCNTs are efficient B and T adsorbents and possess good potential applications to water and wastewater treatment and maintain water of high quality that could be used for cleaning up environmental pollution.
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Abstract

Zinc (II) removal using low-cost sorbents requires a proper process parametric study to determine its optimal performance characteristics. In this respect, the present study proposes a new modeling and simulation procedure for heavy metal removal system and is carried out to optimize input variables such as initial pH, adsorbent dosage, and contact time for biosorption of Zinc (II) by using bentonite. The proposed experimental system is cost-effective and requires less calculation for determining optimal values, i.e., input variables and their related removal capacity, Rem%. To optimize the adsorption process, cubic spline curve fitting and numerical differentiation techniques are used for required calculations. According to the proposed calculations, the removal capacity is calculated as 98.66%, while the optimal values are calculated as initial pH – 6.76, adsorbent dosage – 1.14 g L-1, contact time – 13 minutes. To evaluate the results, full factor experimental design and 3 way ANOVA test are used for comparison.
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Abstract

Concentrations and elemental composition of fine (PM2.5) and coarse (PM2.5-10) ambient particles, at two sampling points located at the same urban background sites, were investigated. The points were 20 m distant from each other and at various heights (2 and 6 m) above the ground. A dichotomous sampler, equipped with a virtual impactor, and a cascade impactor were used to sample the dust. An X-ray fluorescence spectrometer was used in the elemental analyses. The investigations revealed heterogeneity of the spatial distribution and the elemental composition of suspended dust at the investigated urban background site. Coarse dust, whose concentration at 2.0 m above the ground was affected by secondary emission from roads, soil and other local low-level sources in some periods, appeared more heterogeneous.
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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

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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Abstract

Photodegradation by sunlight radiation is one of the most destructive pathways for pesticides after their application in the field. The generated photoproducts can exhibit various toxicological properties and affect non–target organisms. Sulcotrione is a herbicide believed to be a relatively non–toxic alternative to atrazine herbicides used on corn fields. Despite many tests required for placing plant protection products on the market, it still happens that transformation pathway and the toxicological profile of these compounds is not fully understood. The results presented in this article are complementary to the research performed by a research group from National Center for Scientific Research (CNRS) at the University of Blaise Pascal (Auvergne, France). Sulcotrione is one of main herbicides used to protect the maize plantations in the region of Auvergne (France), as well as in Poland. As part of the experiments, the distribution of sulcotrione under the influence of polychromatic radiation (fluorescent lamp, l > 295 nm, suitable for environmental tests) in aqueous solution of pH 6.5 was tested. The main products of these reactions were 1H–xanthene–1,9–dione–3,4–dihydro–6–methylsulfonyl (CP) and 2-chloro-4-methylsulfonyl-benzoic acid (CMBA), which are the result of intra-molecular cyclization and hydrolysis of sulcotrione, respectively. These products were quantified by using HPLC-diode array detector analysis. The studies clearly show an increase in toxicity towards tested organism (Vibrio fischeri bacteria) with the increase of irradiation time and appearance of the photoproducts. The results suggest that the observed increase in toxicity may be rather attributed to the occurrence of the same minor photoproducts than to the presence of the major photoproducts (CP and CMBA). Identification of the minor photoproducts could not be performed using the current instrumental equipment.
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