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1.
The usability of the solid phase extraction method with Tenax-TA adsorbent for the forecasting of polycyclic aromatic hydrocarbon losses during sewage sludges composting has been evaluated in the present study. Four municipal sewage sludges were composted for 76 days. The PAH content in the sludges ranged from 3674 to 11 236 microg kg(-1). After composting, a significant reduction of PAH content was observed. The range of the PAH sum loss ranged from 29.3 to 48.6%. The share of fraction extracted by Tenax-TA in the sludges at the onset of the composting ranged from 28.1 to 54.0% in relation to the PAH sum, and from 0.31 to 100% for individual PAHs. After 76 days of composting, the presence of Tenax-TA extracted PAHs was still observed in the sludges. A significant reduction of this fraction was noted in the case of three sewage sludges. PAH's Tenax-TA fraction in the case of one sewage sludge did not undergo any changes during composting. A satisfactory prediction of PAH losses by the Tenax-TA method was rarely observed. The best reflection of the PAH losses was observed in the case of fluoranthene, anthracene and indeno[1,2,3-cd]pyrene.  相似文献   

2.
The concentrations and removal efficiencies of various kinds of micropollutants were investigated and the relationships between the input sources of industrial wastewater and occurrence patterns of each micropollutant were identified at nine on-site industrial wastewater treatment plants (WWTPs). The distribution pattern of each compound varied according to the WWTP type and several micropollutants were significantly related with specific industries: chlorinated phenols (ClPhs) with paper and metal industries, polycyclic aromatic hydrocarbons (PAHs) with petrogenic- and pyrogenic-related industries, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) with the paper industry, and chlorinated benzenes (ClBzs) with dye-related industries. The activated sludge (AS) process was very efficient in the removal of ClPhs and PAHs, and the filtration process in the removal of PCDD/Fs and 1,4-dioxane. Generally, the removal efficiencies of each micropollutant varied according to the WWTP type.  相似文献   

3.
Disinfection by-product formation potentials (DBPFPs) in wastewater effluents from eight wastewater treatment plants (WWTPs) were investigated. In addition, a WWTP with one primary effluent and two different biological treatment processes was selected for a comparative study. Formation potential tests were carried out to determine the levels of DBP precursors in wastewater. WWTPs that achieved better organic matter removal and nitrification tended to result in lower DBPFPs in effluents. For the WWTP with two processes, haloacetic acid, trihalomethane, and chloral hydrate precursors were predominant DBP precursors in the primary and secondary effluents. The percent reductions of haloacetonitrile and haloketone formation potentials averaged at 96% which was high in comparison to the reductions of other classes of DBPFPs. In addition, biological treatment changed the DBPFP speciation profile by lowering the HAAFP/THMFP ratio. The eight plant survey and the comparative analysis of the WWTP with two processes implied that besides nitrification, there may be other confounding factors impacting DBPFPs. Oxic and anoxic conditions, formation and degradation of soluble microbial products had impacts on the DBPFP reductions. This information can be used by water and wastewater professionals to better control wastewater-derived DBPs in downstream potable water supplies.  相似文献   

4.
The main goal of this study was to evaluate the impacts of a middle-sized Finnish urban area on the quality of sediments in an adjacent boreal lake. We investigated the sources and distribution of organic pollutants (polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs)) in the sediments from urban stormwater traps and from Lake Vesijärvi. Grab surface sediment samples were taken from Lake Vesijärvi at various distances (25–2,000 m) from four major stormwater drainage outlets and at 15 urban stormwater traps in areas with different degrees of urbanization. These samples were analysed for 16 PAHs and 28 PCBs with gas chromatography–mass spectrometry. The concentrations of pollutants in the lake sediments were elevated in the vicinity of the urban shore (∑PAH 3–16, ∑PCB up to 0.02–0.3 mg/kg dw) and decreased as a function of distance (∑PAH 0.1–2.5, ∑PCB 0.01–0.3 mg/kg dw at a distance of more than 500 m from the shore), whereas contamination levels in suburban areas were notably lower (∑PAH 0.1–3, ∑PCB?<?LOQ–0.03 mg/kg dw; did not decline with distance). Possible sources and pathways of contamination were also investigated. The majority of stormwater trap sediments contained predominantly asphalt-derived PAHs due to pulverized pavement. PAHs in lake sediments were of pyrogenic origin, including the combustion of gasoline, diesel and coal. Suggested pathways of lake contamination are urban runoff discharge, boat traffic and atmospheric deposition.  相似文献   

5.
The presence of the anesthetic lidocaine (LDC), the analgesic tramadol (TRA), the antidepressant venlafaxine (VEN) and the metabolites O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) was investigated in wastewater treatment plant (WWTP) effluents, in surface waters and in groundwater. The analytes were detected in all effluent samples and in only 64% of the surface water samples. The mean concentrations of the analytes in effluent samples from WWTPs with wastewater from only households and hospitals were 107 (LDC), 757 (TRA), 122 (ODT), 160 (VEN) and 637 ng L(-1) (ODV), while the mean concentrations in effluents from WWTPs treating additionally wastewater from pharmaceutical industries as indirect dischargers were for some pharmaceuticals clearly higher. WWTP effluents were identified as important sources of the analyzed pharmaceuticals and their metabolites in surface waters. The concentrations of the compounds found in surface waters ranged from 相似文献   

6.
The mass flows of selected pharmaceuticals and personal care products (PPCPs) were studied in the aqueous compartment of the river Somes in Romania. PPCPs were measured in wastewater treatment effluents and in the receiving river water. The analytical method for the determination of PPCPs in river water was based on solid phase extraction and GC-ITMS. Carbamazepine, pentoxyfylline, ibuprofen, diazepam, galaxolide, tonalide and triclosan were determined in wastewater effluents with individual concentrations ranging from 15 to 774 ng L(-1). Caffeine was measured at concentrations up to 42 560 ng L(-1). Due to the high contamination of WWTP effluents, the receiving river was also polluted. The most abundant PPCPs measured in the Somes were caffeine, galaxolide, carbamazepine and triclosan. They were present at all the 15 sampling sites along the Somes, the concentrations ranging from 10 to 400 ng L(-1). The concentrations in the effluents of the different wastewater treatment plants (WWTPs) varied considerably and the differences are due to different elimination efficiencies of the studied PPCPs during sewage treatment. Only one of 5 WWTPs studied, the WWTP in Cluj-Napoca, was working properly, and therefore technical measures have to be taken for upgrading the WWTPs and reducing the environmental load of micropollutants. This study is the first overview of PPCPs along on Romanian part of river Somes.  相似文献   

7.
多环芳烃(PAHs)是一类极其复杂的有机污染物,衍生物种类较多,1976年美国环保局因其致癌、致畸、致突变将其中的16种列为优先控制污染物。城市污水处理厂作为一个地区污染物迁移和转化的重要媒介,在控制和截断PAHs进入天然水体的过程中扮演着重要的角色。因此,研究污水处理厂中PAHs的浓度水平对于了解和控制PAHs进入天然水体和通过污泥进入到土壤中进而通过食物链危害人类健康具有重要的意义。文章综述了污水处理厂污水和污泥中PAHs的前处理技术、分析方法、浓度水平、生态风险以及国内外污水处理厂污泥土地利用现状。  相似文献   

8.
Endocrine-disrupting compounds (EDCs) are exogenous substances that cause adverse health effects in an intact organism, or its progeny, subsequent to the changes in endocrine function. Recent studies have shown that wastewater treatment plant effluents play an important role in the release of EDCs into aquatic environments. Therefore, in this study, influent and effluent samples from three different wastewater treatment plants (WWTPs) in Istanbul were analysed for the presence of the principal EDCs. These chemicals include steroids and synthetic organic chemicals. Thus, the occurrence and fate of EDCs of great health concern were monitored at three WWTPs in Istanbul. Furthermore, these WWTPs are employing different treatment processes. Therefore, the EDC removal performances of different treatment regimes were also evaluated. Phytosterol was the most abundant EDC in the influent samples. Second group of compounds at high influent levels were alkyl phenols. Pesticide levels of all three WWTP influent samples were low. Pasakoy Advanced WWTP is more effective at eliminating EDCs. Kadikoy Primary WWTP exhibits the lowest EDC elimination efficiencies. To the best of our knowledge, this work comprises the first detailed report on the occurrence and behaviour of both natural and synthetic EDCs in WWTPs of Istanbul and Turkey. The steroid estrogen levels of this study are higher than the previously documented values, except the levels given for Gaobeidian WWTP in Beijing, China. This is attributed to higher population densities of Beijing and Istanbul and as well as to lower individual water consumption rates in the two cities.  相似文献   

9.
In this study, the occurrence and distribution of polycyclic aromatic hydrocarbons (PAHs) were investigated in six sludge samples collected from Guangdong Province, China. Concentrations of PAHs varying from 2,534.1 to 6,926.6 μg kg???1 (dry sludge) were observed in three municipal wastewater treatment plants with phenanthrene (Phe), fluoranthene, and pyrene being the main compounds. In addition, 682.6 μg kg???1 PAHs were detected in one sludge sample from a food processing plant, with fluorene, Phe, and chrysene being the main components. No PAHs were detected in sludge samples obtained from two cosmetic plants. The levels and distributional characteristics of PAHs, polychlorinated biphenyls (PCBs), and polycyclic musks (PMs) from the samples were also compared. The results of this comparison indicated that petrochemical refineries and road traffic played important roles in the PAH loads in sludge, while PMs primarily originated from domestic wastewater and industrial wastewater from cosmetic plants. Finally, the presence of 98.8 μg kg???1 PCBs in sludge suggested diffusional emission sources from electrical components containing PCBs.  相似文献   

10.
Titanium dioxide nanoparticles increasingly will be used in commercial products and have a high likelihood of entering municipal sewage that flows to centralized wastewater treatment plants (WWTPs). Treated water (effluent) from WWTPs flows into rivers and lakes where nanoparticles may pose an ecological risk. To provide exposure data for risk assessment, titanium concentrations in raw sewage and treated effluent were determined for 10 representative WWTPs that use a range of unit processes. Raw sewage titanium concentrations ranged from 181 to 1233 μg L(-1) (median of 26 samples was 321 μg L(-1)). The WWTPs removed more than 96% of the influent titanium, and all WWTPs had effluent titanium concentrations of less than 25 μg L(-1). To characterize the morphology and presence of titanium oxide nanoparticles in the effluent, colloidal materials were isolated via rota-evaporation, dialysis and lyophilization. High resolution transmission electron microscopy and energy dispersive X-ray analysis indicated the presence of spherical titanium oxide nanoparticles (crystalline and amorphous) on the order of 4 to 30 nm in diameter in WWTP effluents. This research provides clear evidence that some nanoscale particles will pass through WWTPs and enter aquatic systems and offers a methodological framework for collecting and analyzing titanium-based nanomaterials in complex wastewater matrices.  相似文献   

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