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991.
本研究考察了污水再生处理系统对颗粒物(包括浊度和粒径分布)和微生物指标(包括隐孢子虫、贾第鞭毛虫、粪大肠菌群和SC噬菌体)的去除特性以及不同指标间的相关关系。研究结果表明,污水再生处理系统对浊度的平均去除率为3.53-log,其中二级生化处理及砂滤对浊度的去除率较高,分别为1.52-log和1.35-log。粒径分析结果表明,絮凝沉淀后粒径均值达到最大值223.2μm;而再生水中粒径均值最小,仅为5.8μm。污水再生处理系统对各微生物指标的去除率为2.96-log~4.11-log。各处理单元中,二级生化处理单元对粪大肠菌群和SC噬菌体的去除率较高,分别为2.81-log及2.14-log;而砂滤对SC噬菌体去除效果较差,仅为0.18-log。从再生处理工艺整体上看,水样浊度、粪大肠菌群、SC噬菌体和两虫浓度具有显著相关性。而对于单个取样点,除污水厂进水中SC噬菌体和两虫浓度表现出一定相关性外,其他情况下各指标与两虫浓度间均无显著相关关系。 相似文献
992.
PCBs, PCNs and PBDEs in sediments and mussels from Qingdao coastal sea in the frame of current circulations and influence of sewage sludge 总被引:2,自引:0,他引:2
Influence of current circulation and sewage sludge on spatial distributions of polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and polybrominated diphenyl ethers (PBDEs) in sediments and mussels from the Qingdao coastal sea were investigated. Total concentrations of PCBs, PCNs and PBDEs in sediments ranged 6.5-32.9, 0.2-1.2, and 0.1-5.5 ngg(-1) dry wt, respectively. The maximum concentrations were all found near the Haibo River mouth, affected by sewage sludge input from the river. Under the current system in Jiaozhou Bay the organic pollutants were subject to deposit on the east side of the bay and trapped inside the bay. Sewage sludge was an important source of PCBs, PCNs and PBDEs in the bay and exponentially magnified the enrichment of PCBs. On the other hand, the congener profiles of PCBs in sediments outside the bay may signify an atmospheric source of PCBs. Total Concentrations of PCBs, PCNs and PBDEs in mussels were 61.4-88.6, 9.0, and 13.8 ngg(-1)lipid, respectively. Mussels enriched significantly PCBs, PCNs and PBDEs relative to the sediments. The total toxicity equivalent quantities (TEQs) of PCNs in mussels were generally lower than that of PCBs. The fluxes of the total PCBs and their TEQs have been decreased steadily since 1950s. The lower chlorinated/brominated congeners of PCNs and PBDEs may exhibit a greater tendency due to less lipophilic and thus a greater probability of being affected by the current circulation in the bay. 相似文献
993.
A fuzzy composting process model 总被引:2,自引:0,他引:2
Qin X Huang G Zeng G Chakma A Xi B 《Journal of the Air & Waste Management Association (1995)》2007,57(5):535-550
Composting processes are normally complicated with a variety of uncertainties arising from incomplete or imprecise information obtained in real-world systems. Previously, there has been a lack of studies that focused on developing effective approaches to incorporate such uncertainties within composting process models. To fill this gap, a fuzzy composting process model (FCPM) for simulating composting process under uncertainty was developed. This model was mainly based on integration of a fractional fuzzy vertex method and a comprehensive composting model. Degrees of influence by projected uncertain factors were also examined. Two scenarios were investigated in applying the FCPM method. In the first scenario, model simulation under deterministic conditions was conducted. A pilot-scale experiment was provided for verifications. The result indicated that the proposed composting model could provide an excellent vehicle for demonstrating the complex interactions that occurred in the composting process. In the second scenario, application of the proposed FCPM was conducted under uncertainties. Six input parameters were considered to be of uncertain features that were reflected as fuzzy membership functions. The results indicated that the uncertainties projected in input parameters will result in significant derivations on system predictions; the proposed FCPM can generate satisfactory system outputs, with less computational efforts being required. Analyses on degree of influence of system inputs were also provided to describe the impacts of uncertainties on system responses. Thus, suitable measures can be adopted either to reduce system uncertainty by well-directed reduction of uncertainties of those high-influencing parameters or to reduce the computational requirement by neglecting those negligible factors. 相似文献
994.
995.
监测井在化工厂区土壤和地下水污染监测中的应用 总被引:2,自引:0,他引:2
文章分析了监测井在化工厂区土壤和地下水污染监测中的应用 ,指出对化工厂区土壤和地下水污染进行有效监测的必要性 ,并探讨化工厂区监测井的整体规划和设计。 相似文献
996.
天津市工业污染源结构分析与产业政策建议 总被引:1,自引:0,他引:1
赵喜梅 《城市环境与城市生态》2000,13(5):33-35
文章通过对天津市工业污染源结构分析,确定了天津市工业污染的重点工业行业、重点污染物排放区域以及各区域的重点排污行业,并在此基础上提出了天津市工业发展的产业政策建议。 相似文献
997.
998.
水解酸化—膜生物反应器处理印染废水 总被引:1,自引:1,他引:0
采用平行比较实验,研究了加入聚合硫酸铝铁(PAFS)的水解酸化—膜生物反应器(MBR)工艺(1号系统)和未加PAFS的水解酸化—MBR工艺(2号系统)对模拟印染废水(简称废水)的处理效果和膜污染状况。实验结果表明,PAFS所形成的含铁含铝活性污泥可以提高废水的COD去除率和脱色率。运行期间1号系统膜污染引起的系统抽吸压力增长速率远小于2号系统。污染膜表面的电子显微镜照片表明加入PAFS后减缓了MBR中活性污泥在膜表面的沉积。1号系统膜组件的污染主要是Fe3+、Al3+及它们的氢氧化物为主的无机物在膜表面和膜孔内沉积所形成;2号系统的膜污染以微生物及其有机代谢产物所形成的污泥层附着为主。 相似文献
999.
Chaocan Li Shouliang Huo Zhiqiang Yu Beidou Xi Xiangying Zeng Fengchang Wu 《Environmental science and pollution research international》2014,21(20):12028-12039
Twenty-nine sediment samples were collected from Lake Chaohu, a shallow eutrophic lake in Eastern China, and were analyzed for 15 priority polycyclic aromatic hydrocarbons (PAHs) to determine the spatial distribution and exposure risks of PAHs. Three receptor models, the principal component analysis-multiple linear regression (PCA-MLR) model, the positive matrix factorization (PMF) model, and the Unmix model, were used in combination with the PAHs diagnostic ratios to investigate the potential source apportionment of PAHs. A clear gradient in the spatial distribution and the potential toxicity of PAHs was observed from west to east in the sediments of Lake Chaohu. ∑15PAH concentrations and the TEQ were in the range of 80.82-30 365.01 ng g?1 d.w. and 40.77-614.03, respectively. The highest values of the aforementioned variables were attributed to urban–industrial pollution sources in the west lake region, and the levels decreased away from the river inlets. The three different models yielded excellent correlation coefficients between the predicted and measured levels of the 15 PAH compounds. Similarly, source apportionment results were derived from the three receptor models and the PAH diagnostic ratios, suggesting that the highest contribution to the PAHs was from coal combustion and wood combustion, followed by vehicular emissions. The PMF model yielded the following contributions to the PAHs from gasoline combustion, diesel combustion, unburned petroleum emissions, and wood combustion: 34.49, 24.61, 16.11, 13.01, and 11.78 %, respectively. The PMF model produced more detailed source apportionment results for the PAHs than the PCA-MLR and Unmix models. 相似文献
1000.