Search results

Filters

  • Journals

Search results

Number of results: 10
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Filtration process is one of the basic and essential processes in technological systems for treatment of municipal, community and industrial wastewater treatment. Filtration process is a subject of numerous published research and theoretical elaborations. This publication concerns theoretical analysis with basic character, and is a verification of theoretical analysis and physical equations describing process of filtration aided with empirical formulas.

Go to article

Authors and Affiliations

Tadeusz Piecuch
Jacek Piekarski
Grażyna Malatyńska
Download PDF Download RIS Download Bibtex

Abstract

Identification of coefficients determining flow resistance, in particular Manning’s roughness coefficients, is one of the possible inverse problems of mathematical modeling of flow distribution in looped river networks. The paper presents the solution of this problem for the lower Oder River network consisting of 78 branches connected by 62 nodes. Using results of six sets of flow measurements at particular network branches it was demonstrated that the application of iterative algorithm for roughness coefficients identification on the basis of the sensitivity-equation method leads to the explicit solution for all network branches, independent from initial values of identified coefficients.

Go to article

Authors and Affiliations

Jacek Kurnatowski
Download PDF Download RIS Download Bibtex

Abstract

The paper presents the results of study on heavy metals in needles of Pinus sylvestris in selected pine forests in Słowiński National Park. It was evidenced that heavy metal contents (Zn, Cu, Mn and Fe) in needles of Pinus sylvestris varied depending on the metal, the age of the needles and the humidity of a forest complex. Variation coefficients of such metals remained at the level of: 13-30% (Zn), 3-6% (Cu), 13-34% (Mn) and 12-30% (Fe) depending on the age of the needles. In the case of Zn, Mn and Fe higher concentrations of researched metal were found in the 2-year-old needles than in 1 year old needles, and in the case of Cu in 1 year old needles than in 2-year-old needles. The increase of zinc concentration found in 1-year-old needles after rainfall sums was (Bw, r = 0.67, p < 0.05, n = 24) and (Bśw, r = 0.39, p < 0.05, n = 24) in 2-year-old needles. The content of the above mentioned metals in needles of dry coniferous forests (Bs), fresh coniferous forests (Bśw) and humid coniferous forests (Bw) of the ground cover constitute the following decreasing series: Mn(323.8) > Fe(103.4) > Zn(65.5) > Cu(5.9).

Go to article

Authors and Affiliations

Agnieszka Parzych
Jerzy Jonczak
Download PDF Download RIS Download Bibtex

Abstract

Thirteen fractions of ambient dust were investigated in Zabrze, a typical urban area in the central part of Upper Silesia (Poland), during a heating season. Fifteen PAH and Cr, Mn, Co, Ni, As, Se, Cd, Pb contents of each fraction were determined. The dust was sampled with use of a cascade impactor and chemically analyzed with an energy dispersive X-ray fluorescence spectrometer (PANalytical Epsilon 5) and a gas chromatograph with a flame ionisation detector (Perkin Elmer Clarus 500). The concentrations of PM1 and the PM1-related PAH and elements were much higher than the ones of the coarse dust (PM2.5-10) and the substances contained in it. The concentrations of total PAH and carcinogenic PAH were very high (the concentrations of PM1-, PM2.5-, and PM10-related BaP were 16.08, 19.19, 19.32 ng m-3, respectively). The municipal emission, resulted mainly from hard coal combustion processes, appeared to be the main factor affecting the air quality in Zabrze in winter.

Go to article

Authors and Affiliations

Wioletta Rogula-Kozłowska
Barbara Kozielska
Krzysztof Klejnowski
Download PDF Download RIS Download Bibtex

Abstract

The inter-reservoir enrichment phenomenon was exploited to curtail the reservoir eutrophication process. The Plawnowice reservoir (South Poland - Upper Silesia Region) has an area of 225 ha, volume of 29 mln m3, and a depth of 15 meters. According to the monitoring results in the years 1993-1998 the reservoir was qualified as hypereutrophic. Beginning in December 2003 a bottom pipe for hypolimnetic withdrawal was installed. In the period 2004-2010 a negative phosphorous balance was achieved. The discharge load of total phosphorous was in the beginning twice as high as the inflowing. During the first eight years with an inflow of 75 Mg P, the removed load of total phosphorus was 103 Mg P. In effect the net balance was 28 Mg P. The load, in respect to the surface area, of 2.2 to 3.3 gP/m2 per year, was reduced to a negative load of - 0.48 to - 3.3 gP/m2. The hypolimnetic maximum concentration of orthophosphates equal to 1.254 mg P-PO4/dm3 in 2004, was reduced to 0.236 mg P-PO4/dm3 in 2011. The respective factors and rate of eutrophication curtailing, including changes of phosphorus compounds have been discussed. Also changes of pH and visibility of the Secchi disc are presented. It was concluded that the presented method of hypolimnetic withdrawal is a lasting and effective process

Go to article

Authors and Affiliations

Maciej Kostecki
Jan Suschka
Download PDF Download RIS Download Bibtex

Abstract

The procedure for simultaneous extraction from soil and determination by means of GC-ECD insecticides: aldrin, dieldrin, endrin and herbicide: atrazine was worked out. The proposed GC-ECD technique provides limits of detection in range 12 μg/mL - 18 μg/mL and 2 μg/mL, for insecticides and atrazine, respectively. Two different types of extraction: microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE) with different solvents were tested to choose the procedure that provides the highest recoveries of analytes and low detection limits, typical for trace analysis (100 ppm or 100 mg/g, IUPAC). On the basis of recoveries and precision both extraction methods were compared. The insecticides recovery from soil samples obtained by UAE were in range 40-85%, coefficient of variation (CV): 1.3-5.0%, whereas for atrazine recovery was below 15% (CV: 8-18%). The most efficient and precise extraction procedure turned out to be MAE with n-hexane: acetone. The recoveries were in range 70-85% for insecticides and 84% for atrazine, CV: 0.4-2.2% and 5.3% for insecticides and atrazine, respectively. The presented MAE-GC-ECD procedure enables extraction and determination of aldrin, dieldrin, endrin and atrazine in soil samples with high recoveries, precision and limits of detections in range 6 ng/g - 8 ng/g in the case of insecticides and 1.5 ng/g for atrazine.

The MAE-GC-ECD procedure was applied for the above mentioned pesticides determination in environmental samples. Soils were collected in agricultural as well as rural areas in Poland. In all cases atrazine was determined in concentration range: 0.0187 mg/g - 0.1107 mg/g. Aldrin and dieldrin was detected in soil samples from two locations.

Go to article

Authors and Affiliations

Marianna Czaplicka
Hanna Barchańska
Anna Giemza
Download PDF Download RIS Download Bibtex

Abstract

In this study, the dependence between volumetric exchange rate (n) in an SBR (Sequencing Batch Reactor) with a modified cycle and simultaneous nitrification and denitrification (SND) efficiency during the treatment of anaerobic sludge digester supernatant was determined. In the SBR cycle alternating three aeration phases (with limited dissolved oxygen (DO) concentration up to 0.7 mg O2/L) and two mixing phases were applied. The lengths of each aeration and mixing phases were 4 and 5.5 h, respectively. Independently of n, a total removal of ammonium was achieved. However, at n = 0.1 d-1 and n = 0.3 d-1 nitrates were the main product of nitrification, while at n = 0.5 d-1, both nitrates and nitrites occurred in the effluent. Under these operational conditions, despite low COD/N (ca. 4) ratio in the influent, denitrification in activated sludge was observed. A higher denitrification efficiency at n = 0.5 d-1 (51.3%) than at n = 0.1 d-1 (7.8%) indicated that n was a crucial factor influencing SND via nitrite and nitrate in the SBR with a low oxygen concentration in aeration phases.

Go to article

Authors and Affiliations

Katarzyna Bernat
Download PDF Download RIS Download Bibtex

Abstract

The primary evaluation of the economic losses caused by water pollution in Shanghai in the year 2009 is made by classification approach in order to provide basis for decision of the relative water management policy. The result shows that the portion of water pollution losses in GDP of Shanghai was 2.7%, which was still lower than the average level of whole China despite of the local high population density and the scale of industry, suggesting to some extent the continuous attention in water protection paid by Shanghai government.

Go to article

Authors and Affiliations

Bin Xu
Yan Liu
Download PDF Download RIS Download Bibtex

Abstract

The aim of our research was to investigate the genotoxic effects of cobalt chloride and copper chloride in mouse bone marrow cells using the micronucleus (MN) assay. The three different concentrations of cobalt chloride (11.2, 22.5 and 45 mg kg-1) and copper chloride (1.17, 2.35 and 4.70 mg kg-1) were injected intraperitoneally to mice for 24 and 48 hours. It was observed that both of these heavy metals induced a significant increase in frequency of micronucleated polychromatic erythrocytes (MNPCE) at different concentrations in mice for 24 and 48 hours when compared with the control. Furthermore, the significant reduction for the polychromatic erythrocyte/normochromatic erythrocyte (PCE/NCE) ratio which is indicative of bone marrow cytotoxicity was observed in bone marrow cells which were treated with copper chloride at all concentrations for 24 and 48 hours. No reduction of the PCE/NCE ratio was observed both 24 and 48 hours after all the doses of cobalt chloride tested as compared to the negative control. These results lead us to the conclusion that copper chloride may have genotoxic and cytotoxic properties due to induction in the frequency of MN and a reduction in PCE/NCE ratio in bone marrow cells of mice, whereas cobalt chloride induced only genotoxic effect in mice bone marrow

Go to article

Authors and Affiliations

Pinar Goc Rasgele
Meral Kekecoglu
Fulya Dilek Gokalp Muranli
Download PDF Download RIS Download Bibtex

Abstract

The paper presents results of research concerning operating of five small wastewater treatment plants working in two different technologies: hydrobotanical wastewater treatment plant and constructed wetland. Each object was designed for the treatment of domestic sewage after preliminary mechanical treatment in a septic tank. Hydrobotanical wastewater treatment plants and one of constructed wetland beds were built for treating sewage produced in educational institutions and resort. In the article attention is paid to possibility of exceeding the maximum allowable concentration of pollutants for three main indicators of pollution: BOD5, COD, and total suspension. The reduction of these indices is required by the Regulation of the Minister of Environment [14] for wastewater treatment plants with PE < 2000. In addition, the paper presents the effects of wastewater treatment to reduce biogens. The best quality of outflow was reached by outflows from constructed wetland treatment plants. None of the observed objects fulfilled the requirements in terms of allowable concentrations for total suspension. The most effective were objects operating in technology of “constructed wetland”.

Go to article

Authors and Affiliations

Katarzyna Pawęska
Krzysztof Kuczewski

This page uses 'cookies'. Learn more