首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
<正>2015年1月26日,国家发改委、财政部、住建部联合下发《关于制定和调整污水处理收费标准等有关问题的通知》(以下简称《通知》),2016年底前,城市污水处理收费标准原则上每吨应调整至居民不低于0.95元,非居民不低于1.4元;县城、重点建制镇原则上每吨应调整至居民不低于0.85元,非居民不低于1.2元。目前,污水处理费主要涵盖在各城市收取的水费中。国观智库发布的报告显示,2013年全国32个城  相似文献   

2.
根据谷里镇提供的水质监测资料、处理要求及现有地形条件,选用A2/O+曝气生物滤池作为该镇污水处理工程的核心处理工艺。该镇污水处理工程的设计规模为5 000 m3/d,污水处理工程的进水水质为pH:6~9 mg/L、CODCr:300 mg/L、BOD5:150 mg/L、氨氮:30 mg/L、TN:35 mg/L、TP:3 mg/L、SS:150 mg/L、动植物油:15 mg/L,经采用A2/O+曝气生物滤池作为该镇污水处理工程的核心处理工艺治理后,预计出水可以达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级A标准。  相似文献   

3.
随着我国村镇生活污水处理技术的快速发展,众多技术被研发和应用在村镇污水处理领域。但村镇污水处理技术在实际应用过程中仍然存在着多种问题,如过度参考城镇经验、技术选择缺乏标准指导和规范、技术装备缺乏标准化等。基于我国村镇污水处理常用技术的主要优缺点分析,梳理了我国村镇污水处理技术的应用现状,并对我国村镇污水处理技术的发展方向进行了展望。目前,我国村镇污水处理技术在适应性、标准化、规范化等方面仍然存在很多问题。未来,村镇污水处理技术需要在标准化、低耗高效、自动化和智能化等方面进行突破,应强化技术设备的适应性。  相似文献   

4.
污水处理设施已经成为中国区域环境质量改善的主要手段,通过对污水处理设施信息的收集整理、分析研究,明晰了中国污水处理设施的基本现状,分析了可能存在的问题并提出了相应的对策和措施,为中国城市污水处理相关研究提供基础和借鉴。截至2013年底,我国共建成各类污水处理设施6 124处,总设计处理能力1.66亿t/d,处理污水451.6亿t。已建成的污水处理设施规模以低于2万t/d为主,平均负荷率为74.4%。现有污水处理设施存在管网配套不合理、进水浓度偏低、负荷率普遍不足、执行排放标准偏低等问题。应从污水处理设施所在区域特点出发,因地制宜地选择合适的主体工艺类型和设计规模,科学配置相关管网设施,有效提高设施利用率。  相似文献   

5.
运用生命周期评价(LCA)方法对西安市北石桥污水净化中心污水处理工艺从其原材料开采和加工开始直到污水厂施工建设、处理运行以及废弃拆除的生命周期全过程资源消耗、能耗和环境影响进行了识别和量化分析,同时结合一维水质稀释模型,提出污水处理环境效益估算模型。采用最大污染权重因子对模型进行计算,结果表明,采用深度处理比常规二级处理多产生1 708.52×109kJ的环境正效益。  相似文献   

6.
本研究旨在为白洋淀淀中村生活污水处理技术选择提供一个优化决策方法。在对国内外农村生活污水处理技术深入调研的基础上,采用二级模糊综合评价法,对14项预选处理技术进行综合评估。首先从处理效果、技术性能以及经济性能三方面对各处理技术进行初级量化评估,再根据其评估数据对各项技术进行二级评估,最后结合淀中村自身特点筛选出较好的生活污水处理技术,探讨最适合白洋淀淀中村生活污水处理的优化方案。纯水村人口相对集中地区可采用人工湿地和水解酸化+人工湿地技术,人口相对分散地区可采用沼气净化技术;半水村人口相对集中地区可采用厌氧滤池+土壤渗滤和人工湿地+氧化塘技术,人口相对分散地区可采用沼气净化技术和土壤渗滤技术。  相似文献   

7.
拼装式反应器是一种采用栓接方式将经过防腐处理的钢板现场拼接的新型的污水处理设备.反应器的设计由反应器罐体结构设计、基础设计及配套产品的嵌接设计3个方面构成;拼装式反应器与成熟的污水处理技术(如UASB、水解工艺、SBR、BAF等)的结合提高了污水处理设备的技术含量.拼装式反应器已在猪场废水、食品加工废水、制药废水、啤酒废水及城市污水等废水处理工程中得到了成功应用.  相似文献   

8.
为了提高污水脱氮效果,在传统A2O工艺的基础上,增加后置缺氧段并与膜生物反应器相结合,构建了AAOA-MBR污水处理中试装置,进行了中试实验。实验结果表明,在进水COD浓度为100.00~280.00 mg/L、TN浓度为18.32~31.86 mg/L、NH+4-N浓度为12.78~24.44 mg/L时,COD、TN和NH+4-N的平均去除率分别达到了90.0%、72.1%和99.0%,出水水质达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中的一级A标准;通过多点进水优化了内源配置,节约了碳源,强化了脱氮效果;采用膜池回流供氧,可在节能的同时保证缺氧池1的缺氧环境,提高了反硝化效果。本文的研究成果为实际污水处理工程市场提供了一套高效脱氮的新工艺。  相似文献   

9.
为响应国家减污降碳政策的号召,满足污水处理行业碳排放核算与评价的实际需求,根据碳排放核算标准化工作需要,中国环境保护产业协会于2022年6月首次发布了污水处理厂低碳相关的团体标准——《污水处理厂低碳运行评价技术规范》(T/CAEPI-2022)。该标准是我国污水处理领域首个低碳团体标准,规定了以城镇污水处理厂为主的污水处理厂碳排放核算的方法和低碳运行的评价等级划分,适用于污水处理厂的碳排放核算、低碳运行评价、低碳设计和改造等方面。从标准制订背景出发,阐述了碳排放强度核算和评价的依据、基本条件、内容、流程,并通过案例以期为广大同行理解标准、落实标准和推广标准提供参考。  相似文献   

10.
以浙江《农村生活污水处理设施水污染物排放标准》(DB33/973—2015)的修订为研究切入点,对比了现行标准与国家和浙江农村生活污水治理的管理要求,分析了浙江农村生活污水处理现状并梳理其他省(自治区、直辖市)标准情况.研究发现DB33/973—2015已不符合浙江实际情况且不能满足浙江对农村生活污水的管理需求,必须开...  相似文献   

11.
Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.  相似文献   

12.
Book review     
The Pesticide Manual ‐ A World Compendium, 8th Edition, C.R. Worthing, Editor and S.B. Walker, Assistant Editor, British Crop Protection Council, BCPC Publications Sales, Bear Farm, Binfield, Bracknell, Berkshire RG12 5QE, England. 1987, 1100 pp., UK £50; Overseas £56. ISBN 0–948404–01–9.  相似文献   

13.
Organochlorine compounds in a three-step terrestrial food chain   总被引:1,自引:0,他引:1  
The concentrations of 15 organochlorine chemicals (PCBs and pesticides) were studied in a Central European oak wood food chain system: Great tit (Parus major), caterpillars (Tortrix viridana, Operophtera brumata, Erannis defoliaria), and oak-leaves (Quercus robur). Juvenile tits receive organochlorines from the mother via egg transfer and, eventually to a greater extent, from the caterpillar food source during nestling period. The concentrations of PCB 153 (2,2′,4,4′,5,5′-hexachlorobiphenyl, the most abundant in this study) was found in leaf material at ca. 1 ng/g, in caterpillars 10 ng/g, and in bird eggs 170 ng/g on an average and on a dry mass basis.  相似文献   

14.
Abstract

The active ingredients in commercial formulations of malathion, oxamyl, carbaryl, diazinon, and chlorpyrifos diluted to “spray tank”; concentrations with buffered distilled or natural water of pH 4–9 were stable for at least 24 hr. Formulations of trichlorfon were not stable at pH 7 or above but disappearance rates were slower than for the pure chemical in homogeneous solution. Cupric ion was observed to be an effective catalyst for the hydrolysis of a variety of pure organophosphorus insecticides but did not catalyze hydrolysis of the active ingredients of the formulations examined. Increasing the dilution of the formulation increased the susceptibility of malathion, oxamyl, and carbaryl to hydrolysis.  相似文献   

15.
Abstract

One of the dominant tree species growing within and around the eastern portion of Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis). Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food—the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of 3H, 137Cs, 90Sr, totU, 238Pu, 239, 240Pu, and241 Am in soils (0‐ to 12‐in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (3) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of 3H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 lb [4.5 kg]) was 0.0018 mrem (0.018 μSv); this is far below the International Commission on Radiological Protection (all pathway) permissible dose limit of 100 mrem (1000 μSv). Soil‐to‐nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables.  相似文献   

16.
Degradation and sorption/desorption are important processes affecting the leaching of pesticides through soil. This research characterized the degradation and sorption of imidacloprid (1-[(6-chloro-3-pyridinyl)-methyl]-N-nitro-2-imidazolidinimine) in Drummer (silty clay loam) and Exeter (sandy loam) surface soils and their corresponding subsurface soils using sequential extraction methods over 400 days. By the end of the incubation, approximately 55% of imidacloprid applied at a rate of 1.0 mg kg?1 degraded in the Exeter sandy loam surface and subsurface soils, compared to 40% of applied imidacloprid within 300 days in Drummer surface and subsurface soils. At the 0.1 mg kg?1 application rate, dissipation was slower for all four soils. Water-extractable imidacloprid in Exeter surface soil decreased from 98% of applied at day 1 to > 70% of the imidacloprid remaining after 400 d, as compared to 55% in the Drummer surface soil at day 1 and 12% at day 400. These data suggest that imidacloprid was bioavailable to degrading soil microorganisms and sorption/desorption was not the limiting factor for biodegradation. In subsurface soils > 40% of 14C-benzoic acid was mineralized over 21 days, demonstrating an active microbial community. In contrast, cumulative 14CO2 was less than 1.5% of applied 14C-imidacloprid in all soils over 400 d. Qualitative differences in the microbial communities appear to limit the degradation of imidacloprid in the subsurface soils.  相似文献   

17.
Abstract

Five organophosphorous insecticides: Leptophos, EPN, Cyano‐fenphos, trichloronate and salithion proved to cause irreversible ataxia not only to chicken but also to mice and sheep. TOCP was included as a reference. Cyanofenphos blocked the catecholamine B‐receptor binding activity with 3H‐norepinephrine at a level similar to that of the specific inhibitor propranolol in the mouse heart preparation. In the lamb heart preparation, the B‐receptor was more sensitive to Leptophos, salithion and TOCP than to propranolol. The six compounds and their oxons were screened for their in‐vitro inhibition to monamine oxidase (MAO), acetyl cholinesterase (AChE) and neurotoxic esterase (NTE) in the brain of either mouse, lamb or chicken. It is believed that their AChE inhibition stands for their acute toxicity, while NTE inhibition is responsible for their paralytic ataxia.  相似文献   

18.
土壤中砷的化学平衡   总被引:2,自引:0,他引:2  
本文比较详细地综述了砷的化学特性,环境背景值及来源和循环,土壤中砷的三大化学平衡即沉淀溶解平衡,氧化还原平衡,吸附解吸平衡,以及微生物对砷的转化。  相似文献   

19.
The total concentration of toxic elements (aluminum, cadmium, chromium and lead) and selected macro and micro elements (iron, manganese, copper and zinc) are reported in six leafy edible vegetation species, namely lettuce, spinach, cabbage, chards and green and red types of Amaranth herbs. Although spinach and chards had greater than 125 mv of iron, both the amaranthus herbs recorded > than 320 μ g g? 1 dry weight. In both the spinach and chard species, the Mn and Zn levels were appreciable recording > 225 μ g g? 1 and 150 μ g g? 1 dry weight, respectively. Aluminum concentrations were (in μ g g? 1 dry weight) lettuce (10), cabbage (11), spinach (167), chards (65), amaranthus green (293) and amaranthus red (233). All the micro and macro elements and the toxic elements (Ni, Cr, Cd and Pb) elements analyzed, were below the recommended maximum permitted levels (RMI) in vegetables. Further the elemental uptake and distribution of the nine elements, at three growth stages of the lettuce plant grown on soil bed under controlled conditions are detailed. In the soil, except for iron (16%), greater than 33% of the other cations were in exchangeable form. Generally in the lettuce plant, roots retained much of the iron (> 224 μ g g? 1) and aluminum (> 360 μ g g? 1), while leaves had less than 200 μ g g? 1 of iron and 165 μ g g? 1 of Al. Although the concentrations of elements marginally decreased with growth, the lettuce leaves had significant amounts of Mn (30 μ g g? 1), Zn (50 μ g g? 1) and Cu (3.6 μ g g? 1). Some presence of lead in leaves (2.0 μ g g? 1) was noticed, but all the toxic and other elements analyzed were well below the RMI values for the vegetables.  相似文献   

20.
Abstract

The dissipation of 1.0 ppm nonylphenol in stream and pond water, incubated in flasks at 16°C under simulated field conditions up to 44 days indicated that the half‐life was 2.5 days if the flasks were open, and 16 days if they were closed. A transformed product was detected in the closed flasks.

Translocation of nonylphenol in water occurred when treated water samples were incubated in the presence of sediment. After 10 days, nonylphenol was detected only in the sediment, but not in water (detection limit = 10 ppb). About 80% of the nonylphenol was degraded in 71 days, but no degradation occurred if the water and the sediment were autoclaved prior to incubation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号