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Number of results: 6
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Abstract

The aim of this study was to examine the pollution level of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and selected chloroorganic pesticides (HCH isomers, DDT and its metabolites, aldrin, dieldrin, endrin, heptachlor, endosulfan I and II, and methoxychlor) in surface sediments from selected fjords, tidal plains and lakes from the North Svalbard area. The sediments were collected from 34 sampling stations in July 2005. Only endosulfan I and methoxychlor, among selected chloroorganic pesticides, were measured in concentrations near detection limit (LoD) in fourteen sediment samples. The sum of seven PCB congeners varied from < 0.9 to 5.6 ng g-1 d.w. in sediments from fjords and tidal plains and from < 0.1 to 14.6 ng g-1 d.w. in sediments from lakes. The concentrations of analysed PAH compounds in surface sediments from lakes were over ten times higher (Ʃ16PAHs to 429 ng g-1 d.w.) than in sediments from fjords and tidal plains (Ʃ16PAHs to 36 ng g-1 d.w.).
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Abstract

The paper presents the results of studies on the changes in the PAHs concentration during pre-filtration and ultrafiltration (UF) processes. In the study, biologically treated wastewater (after denitrification and nitrification processes), discharged from the biological treatment plant and used in coke plant, was used. A gas chromatography-mass spectrometry (GC-MS) was used in order to qualify and quantify the PAHs. Sixteen PAHs listed by EPA were determined. The wastewater samples were collected three fold and initially characterized for the concentration of nitrate nitrogen, ammonium nitrogen, COD, TOC and pH. In the first step, wastewater was filtrated on the sand bed. Total concentration of 16 PAHs in the treated wastewater before initial filtration was in the range of 44.8‒53.5 mg/L. During the process the decrease in the concentration of the most studied hydrocarbons was observed. Concentration of PAHs after initial filtration ranged from 21.9 to 38.3 μg/L. After the initial filtration process the wastewater flew to the ultrafiltration module and then was separated on the membrane (type ZW-10). The total concentration of 16 PAHs in the process of ultrafiltration was in the range of 8.9‒19.3 mg/L. The efficiency of removal of PAHs from coke wastewater in the process of ultrafiltration equaled 66.6%. Taking into account the initial filtration, the total degree of removal of PAHs reached 85%. The obtained results indicate the possibility of using the ultrafiltration process with the initial filtration as additional process in the coke wastewater treatment.
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Abstract

The objective of the experiment was to evaluate the energy efficiency of the phytoremediation process, supported using energy crops. The scope of conducted work includes the preparation of a field experiment. During the evaluation, 2 factors were into consideration – total energy demand and total energy benefit. The case study, used as an origin of data, consists a 3-years field study, conducted with the use of 2 energy crops – Phalaris arundinacea L. and Brassica napus L. The area subjected to the experiment was polluted with polycyclic aromatic hydrocarbons (PAHs) and herbicides, classified as phenoxy acids (2, 4 D). The experimental design consisted of 4 groups of fields, divided according to the used plant species and type of treatment. For each energy crop, 2 types of fertilization strategies were used. Therefore the 1st and 3rd sets of fields were not treated with any soil amendment while the 2nd and 4th sets were fertilized with compost. The obtained data allowed to observe that the cultivation of P. arundinacea L. and B. napus L. allowed a positive energy balance of the process to be achieved. However, it should be noted, that the B. napus L. growth in the first vegetation season was not sufficient to fully compensate a total energy demand. Such a goal, in the mentioned case, was possible after the 2nd vegetation season. The collected results show also that the best energetic potential combined with the most effective soil remediation were obtained on the fields with the cultivation of P. arundinacea L. fertilized with compost. The number of biofuels, collected from the 1 ha of such fields, can reach a value equal even to12.76 Mg of coal equivalent.
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Abstract

The work presents examination results of the common determination of PAHs and PCBs in industrial sludge and supernatants. Sewage sludge was taken from the wastewater treatment plant, and supernatants were obtained by their centrifuging. The prepared samples of sewage sludge and supernatants were subjected to extraction with applying the mixture of organic solvents. Cyclohexane and dichloromethane were used for constant samples, and methanol, cyclohexane and dichloromethane - for liquid. Extracts, after separation from samples of sewage sludge and supernatants, were cleared on the silica gel in vacuum conditions and concentrated in the stream of nitrogen. In such prepared extracts there was conducted the qualitative-quantitative analysis of 16 PAHs using the GC-MS system. Next, the samples were evaporated and poured with water and methanol until the clear solution was obtained. Extracts were cleared on octadecyl C18 columns, and then concentrated in the nitrogen stream. In these extracts PCBs was also determined with the application of the gas chromatograph with mass spectrometer. The range of concentrations 16 PAHs in sewage sludge equalled 10-16 mg/kgd.w. Summary average concentration 16 PAHs in supernatants was reached 17 μg/L. Average recovery of PAHs introduced to sewage sludge in the form of reference mixture was 78% (with consideration of naphthalene). In the case of supernatants, the average value of recovery reached 60%. Average PCBs concentration in supernatants equalled 10 ng/L. For sewage sludge the sum of marked PCBs was an average 1.23 μg/kgd.w.. In the case of particular PCBs the percentage recovery of the reference mixture for supernatants was 86%, while for sewage sludge it was 55%.
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Abstract

The furan resin offers advantages such as high intensity, low viscosity, good humidity resistance and is suitable for cast different casting alloys: steel, cast iron and non-ferrous metal casting. For hardening furan resins are used different hardeners (acid catalysts). The acid catalysts have significant effects on the properties of the cured binder (e,g. binding strength and thermal stability) [1 - 3]. Investigations of the gases emission in the test foundry plant were performed according to the original method developed in the Faculty of Foundry Engineering, AGH UST. The analysis is carried out by the gas chromatography method with the application of the flame-ionising detector (FID) (TRACE GC Ultra THERMO SCIENTIFIC).
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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.
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