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排序方式: 共有417条查询结果,搜索用时 62 毫秒
391.
The production of biosolids in three Spanish wastewater treatment plants (WWTPs) has been investigated. Biosolids produced from the treatment of urban wastewater in Spain are usually intended for agricultural use. The reliable production of biosolids mainly depends on both the quantity of suspended solids and the organic load influent to the treatment systems. The quality of the generated biosolids was independent of both the amount of treated water and the treatment process applied, with 20 to 25% dried matter, and 60 to 75%, 7% and 4% of organic matter, N and P, respectively, of the total matter. The biosolids contained ca. 11 to 19 g/kg of total metals in the dry matter, with Fe, Zn, Cu and Mn representing 97% of all of the metals present, and Hg being the minority metal. Such biosolids had the ability to concentrate the organic matter and metals from the wastewater up to 417 and 869 times, respectively, and thus, can be used in agricultural practice.  相似文献   
392.
表面流人工湿地处理糠醛生产废水的应用   总被引:2,自引:0,他引:2  
根据糠醛生产废水的特点,利用生产企业所处低洼盐碱地改造成表面流人工湿地,废水在湿地内以自然消耗的方式处理,无外排,处理的废水量等于湿地内废水的自然蒸发量、植物的蒸腾量与植物的贮存量。研究表明,经湿地处理后的废水COD去除率平均为94%,TN去除率平均为65%,TOC去除率平均为94.9%。处理后的废水pH值为6.22。  相似文献   
393.
膜生物反应器处理难降解废水的特性研究   总被引:3,自引:3,他引:0  
膜生物反应器与生物接触氧化法处理难降解废水的对比研究表明,在相同的运行条件下,膜生物反应器比生物接触氧化法具有更稳定的出水水质,其平均出水CODcr去除率达到88.41%,比接触氧化法提高了近30%;其平均色度去除率达到85.27%,相比接触氧化法,提高了近30%。通过出水分子量组成分析发现,膜出水以分子量介于3 000和10 000之间的物质为主,占总数的88.36%,接触氧化以分子量大于10 000的物质为主,占总物质的72.04%,介于3 000和10 000之间的仅占9.76%。  相似文献   
394.
The performance of a constructed wetland for wastewater treatment was examined for four months (December 1995 to March 1996). The study area, hereby referred to as the Splash wetland, is approximately 0·5 ha, and is located in the southern part of Nairobi city. Splash wetland continuously receives domestic sewage from two busy restaurants. Treated wastewater is recycled for re‐use for various purposes in the restaurants. Both wet and dry season data were analysed with a view of determining the impact of seasonal variation on the system performance. The physical and chemical properties of water were measured at a common intake and at series of seven other points established along the wetland gradient and at the outlet where the water is collected and pumped for re‐use at the restaurants. The physico‐chemical characteristics of the wastewater changed significantly as the wastewater flowed through the respective wetland cells. A comparison of wastewater influent versus the effluent from the wetland revealed the system's apparent success in water treatment, especially in pH modification, removal of suspended solids, organic load and nutrients mean influent pH = 5·7 ± 0·5, mean effluent pH 7·7 ± 0·3; mean influent BOD5 = 1603·0 ± 397·6 mg/l, mean effluent BOD5 = 15·1 ± 2·5 mg/l; mean influent COD = 3749·8 ± 206·8 mg/l, mean effluent COD = 95·6 ± 7·2 mg/l; mean influent TSS = 195·4 ± 58·7 mg/l, mean effluent TSS = 4·7 ± 1·9 mg/l. As the wastewater flowed through the wetland system dissolved free and saline ammonia, NH4+, decreased from 14·6 ± 4·1 mg/l to undetectable levels at the outlet. Dissolved oxygen increased progressively through the wetland system. Analysis of the data available did not reveal temporal variation in the system's performance. However, significant spatial variation was evident as the wetland removed most of the common pollutants and considerably improved the quality of the water, making it safe for re‐use at the restaurants. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
395.
含苯并三唑废水是一类常规方法不能处理的化工废水,需要探讨有效的处理方法。在纳米科技理论指导下,以纳米微粒的吸附特性为切入点,确立了纳米微粒与无机高分子混凝剂最佳混凝形态之间联系的纽带。围绕混凝作用进行了纳米粉体材料混凝试验、无机高分子混凝剂混凝试验和电凝聚试验。结果发现,应用电凝聚法能有效去除废水中由苯并三唑产生的COD,从而成功地探索出有效处理含苯并三唑废水的方法。  相似文献   
396.
Water pollution of river basin has increased with increasing discharge of sewage and the water quality has deteriorated due to the discharge of organic wastewater. Pretreatment of organic wastewater before discharging is of significance for the protection of water resources. The anaerobic digestion of organic substrates has been a well-developed biological treatment method for wastewater and wastes. Especially, the biohydrogen production using organic wastewater can produce an energy product and simultaneously reduce the pollution intensity of the wastes. Microorganisms with high hydrogen-producing capacity perform an important function in biohydrogen production. In this paper, we investigated the zymolytic characteristics of a novel strain of bacteria B49 isolated from anaerobic activated sludge using waste liquid from a sugarhouse as substrate. The effect of yeast extract on microbial conversion of waste liquid from the sugarhouse was investigated. Different carbohydrates (such as glucose, sucrose, trisaccharide, molasses, etc.) in the waste liquid serve as major energy sources for B49's cell growth. The hydrogen yield of 2410 mL-H2/L-culture was obtained using glucose as substrate. When the waste liquid from the sugarhouse (molasses) was used as substrate, maximum hydrogen yield of 2460 mL-H2/L-culture was obtained at 2% of molasses.  相似文献   
397.
主要介绍了碳材料在石油废水处理,给排水水质处理、大气治理中的应用。膨胀石墨含有大量孔隙,密度很低,用作吸附材料可以治理石油废水。碳材料可作为生物增殖的载体,分解生物能降解的污染物。用于给排水水质处理,能够提高水质;而经过特殊处理的石墨可以与金属纳米复合,形成金属基石墨层间化合物,改善石墨的抗菌性能。碳材料的比表面积大,可用作气相污染物的吸附脱除材料,在大气污染方面,表现出良好的应用前景。  相似文献   
398.
Abstract

Semi-arid coastal zones often suffer water-stress, as water demand is high and markedly seasonal, due to agriculture and tourism. Driven by scarcity of surface water, the communities in semi-arid coastal regions turn to aquifers as prime water source; but intensive exploitation of coastal aquifers causes seawater intrusion, which degrades the quality of groundwater. The cost-efficient and sustainable development of coastal aquifers can be achieved through a holistic management scheme which combines two non-traditional water sources: (a) saltwater, to be treated to the desired quality, and (b) wastewater, to be re-claimed to augment aquifer recharge for control of seawater intrusion, and also to meet certain demands. This management scheme is based on the idea that it is cost-advantageous to: (i) desalt brackish groundwater, instead of seawater, as the former requires far less energy, and (ii) to re‐use wastewater at only the differential cost to any treatment already practiced. In this paper, we present the general framework of the proposed management scheme, and a decision aid tool (DAT) which has been developed to assist decision makers to explore the scheme's decision space. The DAT uses cost as optimization criterion to screen various management scenarios, via modelling of the dynamic natural-engineered system behaviour, and identifies those cost-efficient ones that meet the water demand and achieve aquifer protection.

Citation Koussis, A. D., Georgopoulou, E., Kotronarou, A., Lalas, D. P., Restrepo, P., Destouni, G., Prieto, C., Rodriguez, J. J., Rodriguez-Mirasol, J., Cordero, T. & Gomez-Gotor, A. (2010 Koussis, A. D., Georgopoulou, E., Kotronarou, A., Mazi, K., Restrepo, P., Destouni, G., Prieto, C., Rodriguez, J. J., Rodriguez-Mirasol, J., Cordero, T., Schwartz, J., Ioannou, C., Georgiou, A. and Zacharias, I. 2010. Cost-efficient management of coastal aquifers in water-stressed regions via recharge with treated wastewater and desalination of brackish groundwater: application to the Akrotiri basin and aquifer, Cyprus. Hydrol. Sci. J, 55(7): 12341245. [Taylor & Francis Online], [Web of Science ®] [Google Scholar]) Cost-efficient management of coastal aquifers via recharge with treated wastewater and desalination of brackish groundwater: general framework. Hydrol. Sci. J. 55(7),1217–1233.  相似文献   
399.
在模拟含Cu2+废水中加入Mg2+和Al3+,以NaOH为沉淀剂,研究金属盐水解即时合成层状双氢氧化物去除Cu2+的可行性,同时考察了体系终点pH值、配料中Mg/Cu摩尔比值及反应温度和时间对Cu2+去除率的影响,探讨了Cu2+去除机理及层状双氢氧化物形成过程。结果表明,实验条件下体系终点pH值显著影响Cu2+去除率,在pH值8.0~11.0范围内去除效果较好,达99%以上。通过X射线衍射分析结合即时合成法特点,废水中Cu2+主要是在晶核生成阶段以Cu/Mg/Al三元层状双氢氧化物形式被去除;三元层状双氢氧化物的形成由反应体系中Al3+、Cu2+、Mg2+分步水解导致,最适pH值约为9.0。  相似文献   
400.
《地学前缘》2012,38(1)
采用厌氧/缺氧/好氧膜生物反应器对北京某城市污水处理厂的初沉池出水进行中试试验,约200 d的研究表明,在水力停留时间保持12.5 h后,化学需氧量、生物需氧量及总有机碳的去除率分别稳定在92%、98%、85%左右,其中生化降解部分与膜过滤部分对COD去除的贡献率分别为89%和11%;NH4+-N、总氮(total nitrogen,TN)的去除率分别为98%、79%左右,出水ρ(TN)平均在10 mg/L左右;系统在污泥龄为40 d左右时,总磷(totalphosphorus,TP)平均去除率为85%,出水ρ(TP)在0.93 mg/L左右;反硝化除磷、好氧吸磷、膜截留对总磷的去除所占的比例分别为44.6%、51.8%、3.6%;出水浊度极低且几乎无悬浮物,可直接回用于城市杂用水.间歇抽吸、曝气冲刷、在线水力反冲及定期药洗保证了该系统的可持续运行.  相似文献   
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