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1.
本文通过对城市污水常用的两种处理方法——污水二级处理和污水潜没排海(江)的经济、环境损益分析,揭示了两种处理方法固有的优劣,从而得出;对具有大容量受纳水体的城市,采用污水潜没排海(江)处理城市污水更为合理。  相似文献   

2.
随着城市建设和工业的发展,大量的生活污水和工业废水排放到环境水体中,污水中的有毒、有害组分的有机物也随之带入水体. 北京是首都,人口密集、工业集中且门类繁多,城市污水总量为14.25亿方/年,其中工业污水占60%. 北京排污河为承担北京市污水排放而人  相似文献   

3.
污水处理工程--两段式活性污泥工艺   总被引:1,自引:0,他引:1  
我国中小城市的污水处理通常有如下特点(1 )工业废水所占比重较大,甚至超过50 %,致使要处理的城市污水的污染物浓度较高,污染物负荷变化较大 ;(2)城市财政状况比较紧张,可用于建设污水处理厂的资金有限.两段式活性污泥工艺是对传统活性污泥工艺的改进,在好氧处理之前采用一个缺氧或厌氧段,用于有机物的水解酸化或生物除磷.两段式工艺有以下优点处理效率高、工程投资和日常运行费用低,更适合我国国情.本文以两个工程项目为例,论述了两段式活性污泥工艺的工程设计与实际应用.山东省招远市污水处理厂于1999年7月投入运行,处理后排放水中的污染物指标低于设计值.蓬莱市污水处理厂工程即将竣工,设计处理能力20000m3 /d,工程总投资约1200万元,远远低于目前国内的平均水平.  相似文献   

4.
本文针对嫩江沿岸采用氧化塘处理污水的特点,为充分合理利用水环境容量,以流域总量控制的原则为指导,建立了水污染物总量分配模型,预测不同流量和不同排污情况下的水质,确定不同流量下给定水质目标的临界距离和允许排污量。  相似文献   

5.
以长江口区域开发为例,通过建立平面二维数学模型,预测开发区产生的废水,经污水处理厂处理达标排入长江后,对长江口(北支)湿地自然保护区的水环境影响。预测结果表明,尾水正常排放时,对保护区的影响不大,这为区域开发的环境管理,提供了科学的依据。  相似文献   

6.
大量未经处理的污水排入水体时 ,会导致地面水体严重污染。受污染水体的水质恢复方法有物理法、化学法和生物法 ,它们能控制水体外源性和内源性污染物的排入量、人工强化水体自身的净化能力 ,以降低水体中污染物的浓度、提高溶解氧浓度 ,恢复水生生物的多样性  相似文献   

7.
针对南方典型山塘区农村散排污水未经处理直接入河引起水体水质恶化问题,因地制宜开发了基于给水污泥基质填料的山塘湿地生态治理技术,形成适于山塘区农村散排污水的强化化粪池—潮汐式给水污泥生态填料床—生物塘三级处理新工艺,并进行工程示范。现场试验表明,潮汐式给水污泥生态填料床对COD、氨氮、总氮、总磷的去除率分别为55.66%、87.02%、36.77%、91.62%,新工艺最终出水水质达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准。综合经济分析,该工艺运行费用约为0.059 5万元/a,单位污水综合处理成本为0.4元/t,具有经济性、环境友好和可推广性。  相似文献   

8.
污水处理工程——两段式活性污泥工艺   总被引:5,自引:1,他引:4  
我国中小城市的污水处理通常有如下特点:(1)工业废水所占比重较大,甚至超过50%,致使要处理的城市污水的污染物浓度较高,污染负荷变化较大;(2)城市财政状况比较紧张,可用于建设污水处理厂的资金有限,两段式活性污泥工艺是对传统活性污泥工艺的改进,在好氧处理之前采用一个缺氧或厌氧段,用于有机物的水解酸化或生物除磷。两段式工艺有以下优点:处理效率高、工程投资和日常运行费用低,更适合我国国情。本文以两个工程项目为例,论述了两段式活性污泥工艺的工程设计与实际应用。山东省招远市污水处理厂于1999年7月投入运行,处理后排放水中的污染物指标低于设计值。蓬莱市污水处理厂工程即将竣工,设计处理能力20000m^3/d,工程总投资约1200万元,远远低于目前国内的平均水平。  相似文献   

9.
通过中试研究了不同溶解氧浓度、有机负荷、HRT条件下,反应沉淀一体式矩形环流反应器(RPIR)对深圳市南山污水处理厂低C/N城市污水的处理效果。结果表明,在控制溶解氧浓度为1 mg/L、COD容积负荷小于2.5 kg/m3.d、NH4+-N容积负荷不超过0.2 kg/(m3.d)、HRT为4 h时,COD平均去除率可达90%,NH4+-N平均去除率超过80%。RPIR在处理该城市污水过程中具有良好的抗冲击负荷能力,污染物去除效率高,运行稳定。  相似文献   

10.
河道暗渠化是影响城市建成区河流黑臭水体治理的重要因素,为探究河道暗渠化对城市河流水环境的影响,以深圳市龙华区观澜河流域主要支流暗渠为研究对象,通过现场勘查并结合暗渠段水质分析,探讨了暗渠段主要环境问题,并分析了暗渠对河流水质的影响。结果表明:暗渠段对城市河流水质的影响是显著的,主要污染物为氨氮和总磷;污染最为严重的塘水围氨氮的平均值为22.29 mg·L~(-1),为重度黑臭水体氨氮标准(15 mg·L~(-1))的1.49倍,而其氧化还原电位的平均值为-154 mV,远低于轻度黑臭水体标准(50 mV),其中最低值为-190 mV,接近于重度黑臭水体的标准值(-200 mV)。在明渠-暗渠-明渠分布的空间格局中,暗渠内淤泥的大量累积、垃圾的清理不及时、污水排口的封堵不彻底等是造成暗渠段水质恶化的主要原因。在工程解决措施上,应结合区域城市发展规划,遵循"定位、揭盖、加窗、联涵、疏泥"十字方针,通过顶层覆盖物拆除或开窗、挡墙拆除或加固、污水收集与处理、淤泥与垃圾的清除等工程措施实现暗渠段污染的消除。以上研究结果可为城市河流黑臭水体治理和河流暗渠环境综合整治提供参考。  相似文献   

11.
根据上海市水环境污染物排放的现状及有关统计数据,采用Sigmoid模型,对未来的变化趋势进行了预测。并通过上海市污水治理设施状况及其水环境质量状况的调查数据,研究了水环境质量与社会经济发展的关系,进一步分析了水环境质量对上海中长期发展的制约。在此基础上,对改善水环境质量以减少对未来发展的制约,提出了相应的对策与建议。  相似文献   

12.
The physical nature of the Bilbao Estuary (Spain) has been highly modified since the end of the last century, mainly by means of dyking, canalization, and dredging to meet the needs of navigation. Together with its industrial use, the estuary is also used for the disposal of domestic sewage. Until the completion of a sewerage plan in the year 2002, the sewage of about 1 million people and the wastes from industries will continue to be discharged into this 15-km-long estuary with a limited freshwater flow of 25 m(3) s(-1). An abrupt decrease in faunal abundance followed by defaunation characterized the biotic response to the disturbance in almost three-quarters of its tideway. Relationships between biotic and environmental variables were investigated using the BIO-ENV procedure of the PRIMER computer package. Gross organic enrichment, water oxygen depletion and anaerobic sediment conditions appear to be the dominant anthropogenic influences on the Bilbao Estuary. It is concluded that the level of wastewater discharges into the estuary may substantially drop below that concentration which assures the protection and propagation of native heterotrophic resources within sediments. Biological monitoring is thus essential to assess the efficacy of the sewerage plan promoted by the local Water Authority.  相似文献   

13.
以深圳市宝安区为例,探讨以再生水满足城市水系环境需水的方法.应用一维恒定与非恒定水质模型计算了4种补水水质方案下该区10条主要河流的环境需水量,从水量平衡角度提出全区再生水BOD5的平均值,并进一步分析了补水水质与河流环境需水量的关系.结合该区水系与污水处理系统空间位置,提出3种再生水的空间配置方法.结果表明:茅洲河和...  相似文献   

14.
Eighteen organochlorine contaminants from the water samples of the Yangtse River have been qualitatively and quantitatively analyzed. The analysis of polychlorinated organic compounds (PCOCs) extracted by C18 Solid Phase Extract (SPE) was performed using HP6890 gas chromatograph coupled by ECD detector. The analytical results demonstrate that the analytical methods are reliable based on the fact that most of the recoveries for the targeted compounds are 60-90%. Most of the concerned contaminants, i.e. chlorinated pesticides and PCBs were found in the water samples of the Yangtse River, but their concentration was very low, <2.97 ng l(-1), which is far less than 1 microg l(-1)--the standard of drinking water of China. It is apparent that the PCOCs were in high concentration during the dry season, and in low concentration during the rainy season. The situation of PCOCs contamination in the water of the Yangtse River in 1999 was greatly improved in comparison with 10 years ago.  相似文献   

15.
Polycyclic aromatic hydrocarbons (PAHs) in a sediment core taken from intertidal flat in the Yangtze Estuary were determined by gas chromatography-mass spectrometry. The results indicate that the total concentration of PAHs ranged from 0.08 to 11.74 microg/g. The concentration levels of total and individual PAHs changed dramatically with depth. The concentrations of PAHs were relatively high above 35 cm depth and remained constantly low below this depth. The historical record of PAHs in the core shows subsurface maximum (one or more peak values), followed by decreased levels to the surface and with depth. And, PAH sediment record in the core profile is in agreement with historically sewage discharge events during the 1980s to 1990s. The distribution of target molecule acenephthene, the fluoranthene/pyrene ratio, the proportion of 2-3-ring and 4-5-ring PAHs, and alkylated naphthalene to parent naphthalene in the core profile show that the sources in this area are characterized by petroleum-derived PAH contamination (mainly sewage discharge and the river runoff) and the incorporation of atmospheric inputs. Studies indicate the PAH profile pattern in this site in comparison with other regions appear to reflect its particular local position (near the sewage outlet). Moreover, physico-chemical conditions and sedimentation rate as well as biodegradation also affect the PAH concentration levels in the core sediments.  相似文献   

16.
油气田环境保护与控制技术   总被引:3,自引:0,他引:3  
如何控制和减少钻井、采油等作业过程中对环境的危害,一直是国内外众多科学家所研究的问题。介绍了一种从根本上解决和消除钻井、采油过程中对环境污染的油气田环境污染控制技术和各种废钻井液、钻屑、钻井废水及采油污水的处理方法。  相似文献   

17.
Steroid estrogens in ocean sediments   总被引:4,自引:0,他引:4  
This paper gives results from a study measuring the abundance of steroid hormones in ocean sediments in the proximity of a deep ocean sewage outfall. The outfall is discharge point for an enhanced primary sewage treatment plant and sediment samples were taken adjacent and 7 km from the outfall. All samples contained steroid estrogens at nanogram per gram levels with higher concentrations at the 7 km sampling site. The concentration of estrone ranged from (0.16-1.17 ng/g), 17beta-estradiol (0.22-2.48 ng/g) and the synthetic 17alpha-ethinylestradiol (<0.05-0.5 ng/g). The values detected correspond with estimates based on the proportion of estrogens sorbed to particles in the effluent and the expected proportion of particles originating from sewage in the ocean sediments. The results suggest that estrogens associated with the particulate fraction aggregate on contact with high ionic strength seawater and settle to the seafloor after discharge through deep ocean outfalls.  相似文献   

18.
Yan H  Zhang CJ  Zhou Q  Chen L  Meng XZ 《Chemosphere》2012,88(11):1300-1305
Perfluorinated acids (PFAs) are the subject of increasingly intense environmental research. In this study, sewage sludge samples were collected from 25 wastewater treatment plants (WWTPs) in Shanghai, China to evaluate the levels and profile of C3-C14 PFAs. The results showed a ubiquitous PFAs contamination of sewage sludge in Shanghai with the total PFAs (∑PFAs) range of 126-809 ng g(-1)dw. Perfluorooctanoic acid (PFOA) was found to be the dominant PFA pollutant and its concentration ranged from 23.2 to 298 ng g(-1)dw, much higher than the levels in other countries. Moreover, concentrations of short-chain PFAs (相似文献   

19.
城市污水污泥的重金属离子Pb、Zn超过国家固体废弃物排放最高允许值,属于危险废物。污水污泥的最佳出路是无害化处理,资源化利用,产业化发展。研究了以上海市污水污泥为原料,加入一定比例的固化剂和矿物掺合料使之固结,经养护满足路用强度性能,测试其固结体重金属离子浸出质量浓度亦满足国家固体废弃物排放标准,即污泥中的重金属离子得到有效的束缚和稳定固化,既解决了环境问题,又为污泥产业化发展开辟了新的途径。  相似文献   

20.
改善深圳河水质的补水方案及生态影响初步分析   总被引:3,自引:0,他引:3  
深圳河旱季天然径流量小而污染负荷高,为了改善河流水质,在削减入河污染物的同时有必要采取补水措施。利用水质模型,计算了不同污水处理率下,分别以污水资源化再生水、珠江口海水和大鹏湾海水为补水水源时,深圳河达到基本不黑臭所需的补水量。讨论了补水方案对河流水质、盐度、水动力条件的改变及其对生态系统的影响。研究表明,引海水对河流生态系统的冲击不容忽视。而污水资源化是较优的补水方案。  相似文献   

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