混合化工污水处理工艺的试验研究

本文介绍了利用混凝沉淀一生物接触氧化法治理混合化工污水的试验工艺选择,对生化进水的预处理工作进行了初步的探索,在生化试验中,研究了水力停留时间和有机负荷对污水处理效果的影响,并观察了微生物的生长和发展规律,初步探讨了其动力学模型,试验证明：本法能有效地处理混合化工污水,在适宜的条件下,ＣＯＤｃｒ、ＢＯＤ５的去除率可达５５％和９０％以上,色度和ＳＳ的去除率分别可达８０％和５０％以上。     

CHARACTERIZATION OF TOXIC CONDITIONS ABOVE WILSON'S CREEK NATIONAL BATTLEFIELD PARK,MISSOUR1

ABSTRACT: Wilson's Creek has an extensive history of toxicity from both point and nonpoint sources. Seven-day chronic daphnid (Ceriodaphnia dubia) bioassays identified one toxic site in the Wilson's Creek watershed. Procedures for the characterization phase of a Toxicity Identification Evaluation (TIE) were modified for chronic assessment and performed on four water samples from the toxic site. The characterization involved chemical/physical alterations of samples, combined with bioassays, to help in identification of the class(es) of toxicants; followed by chemical analyses. To help understand the additivity of mixtures, toxic units were derived. Successive samples contained concentrations of copper, cadmium, nickel and zinc that literature values describe as being chronically toxic to daphnids. Summed chronic toxic units for these values greatly exceeded ambient toxic units, and more than accounted for observed toxicity. Substantial fluctuations in water quality occurred over the five sampling periods of the characterization studies and a Test of Methods, June through August, 1991. This variability illustrates the difficulty in detecting and documenting nonpoint sources of pollution. Tests using living organisms, in conjunction with toxicity identification methods, on samples taken over time appear to be appropriate for detecting acute and chronic toxicity in areas impacted by intermittent point and nonpoint-source toxicity.     

Chemical industry wastewater treatment

Treatment of chemical industrial wastewater from building and construction chemicals factory and plastic shoes manufacturing factory was investigated. The two factories discharge their wastewater into the public sewerage network. The results showed the wastewater discharged from the building and construction chemicals factory was highly contaminated with organic compounds. The average values of chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were 2912 and 150 mgO₂/l. Phenol concentration up to 0.3 mg/l was detected. Chemical treatment using lime aided with ferric chloride proved to be effective and produced an effluent characteristics in compliance with Egyptian permissible limits. With respect to the other factory, industrial wastewater was mixed with domestic wastewater in order to lower the organic load. The COD, BOD values after mixing reached 5239 and 2615 mgO₂/l. The average concentration of phenol was 0.5 mg/l. Biological treatment using activated sludge or rotating biological contactor (RBC) proved to be an effective treatment system in terms of producing an effluent characteristic within the permissible limits set by the law. Therefore, the characteristics of chemical industrial wastewater determine which treatment system to utilize. Based on laboratory results engineering design of each treatment system was developed and cost estimate prepared.     

EFFICIENCY PROBLEMS FROM USER FEES IN MUNICIPAL WASTEWATER TREATMENT1

ABSTRACT: The Environmental Protection Agency administers a construction grant program to encourage abatement of wastewater pollution by sharing with municipalities the costs of wastewater treatment facilities. The enabling legislation (P.L. 92–500) specifies that EPA's cost share will be 75% of construction costs. It further requires municipalities to collect user fees from industrial users of the facilities to repay that part of the federal grant allocable to the treatment of industrial wastewater. The municipality must return half of the user fees collected to the U.S. Treasury; the municipality is allowed to retain the remaining half. Retention by municipalities of these user fees lowers their effective cost shares and results in the following consequences: (1) a bias for municipalities to select certain kinds of abatement techniques regardless of whether or not they are the least-cost techniques from the national perspective; (2) a bias for municipalities to select larger-than-optimal scales of abatement facilities; (3) a hidden federal subsidy to industry; and (4) grants that favor industrial communities. This article examines the legislative and regulatory requirements for user charges, derives the algebraic expressions for calculating the real federal, municipal, and industrial cost shares with user fees; computes municipal cost shares for selected values of the determinant factors; evaluates efficiency and other consequences of current user fee arrangements; and concludes that the efficiency distortions brought about by the impacts of user fees on cost sharing could be eliminated by requiring that all user fees collected from industry against the federal cost share be returned to the U.S. Treasury.     

Cost-effectiveness of two operational models at industrial wastewater treatment plants in China: A case study in Shengze town,Suzhou City

The widespread illegal discharge of industrial wastewater in China has posed significant challenges to the effective management of industrial wastewater treatment plants (IWTPs) and caused or exacerbated critical social issues such as trans-boundary environmental pollution. This study examines two operational strategies, decentralized model and an innovative integrated model, that have been used in the industrial town of Shengze (located in Suzhou City) over the past two decades at IWTPs handling wastewater from the city’s dyeing industry. Our cost-effectiveness analysis shows that, although the operational cost of IWTPs under the integrated model is higher than under the original decentralized model, the integrated model has significantly improved IWTP performance and effectively reduced illegal discharge of industrial wastewater. As a result, the number of reported incidents of unacceptable pollution in local receiving water bodies had declined from 13 in 2000–1 in 2008. Key factors contributing to the success of the innovative integrated model are strong support from municipal and provincial leaders, mandatory ownership transfer of IWTPs to a centralized management body, strong financial incentives for proper plant management, and geographically-clustered IWTPs.     

Biosolids-derived nitrogen mineralization and transformation in forest soils

Utilization of biosolids through land application is becoming increasingly popular among wastewater managers. To minimize the potential contamination of receiving waters from biosolids-derived nitrogen (N), it is important to understand the availability of N after land application of biosolids. In this study, four secondary biosolids (two municipal and two pulp and paper industrial biosolids) were used in a laboratory incubation experiment to simulate N mineralization and transformation after land application. Municipal biosolids were from either aerobically or anaerobically digested sources, while pulp and paper industrial biosolids were from aerated wastewater stabilization lagoons. These biosolids were mixed with two New Zealand forest soils (top 100 mm of a volcanic soil and a brown soil) and incubated at two temperatures (10 and 20 degrees C) for 26 wk. During incubation, mineralized N was periodically leached from the soil-biosolids mixture with 0.01 M CaCl2 solution and concentrations of NH4 and NO3 in leachate were determined. Mineralization of N from aerobically digested municipal biosolids (32.1%) was significantly more than that from anaerobically digested biosolids (15.2%). Among the two pulp and paper industrial biosolids, little N leached from one, while as much as 18.0% of total organic N was leached from the other. As expected, mineralization of N was significantly greater at 20 degrees C (average 22.8%) than at 10 degrees C (average 9.7%). It was observed that more N in municipal biosolids was mineralized in the brown soil, whereas more N in pulp and paper industrial biosolids mineralized in the volcanic soil. Transformation of NH4 to NO3 was affected by soil type and temperature.     

MBR/RO组合工艺回收处理己内酰胺废水的中试研究

对己内酰胺生产过程废水的回用处理工艺进行了研究。以某己内酰胺化工厂的LUCAS出水作为研究对象,采用膜生物反应器和反渗透膜处理工艺,研究此系统对己内酰胺废水的处理效果。试验结果表明,膜生物反应器工艺适用于该化工厂的生产废水,出水COD平均值为31.33mg/L,平均浊度为0.2NTU,氨氮平均值为2.81mg/L,可以满足反渗透膜的进水要求。在浓缩倍数为3时,反渗透膜系统运行稳定,且产水可以满足化工部循环冷却水用再生水水质标准。     

中国工业废水治理效率评价

基于投入产出的思想,应用DEA模型对2008年中国工业废水治理效率进行静态评价,得出各地区当前工业废水治理效率.用Malmquist指数对中国2003-2008年工业废水治理效率进行动态评价,分别得出近几年中国工业废水治理的名义全要素生产率和实际全要素生产率.结果表明,中国工业废水平均治理效率仅为0.630,2008年达到DEA有效的地区仅占16.7％,几乎所有地区都处在规模收益递减;2003-2008年间的中国工业废水治理名义T下P为0.922,实际TFP为0.943,即分别在此期间平均每年下降7.8％和5.7％,造成逐年下降的主要原因是技术的落后.     

Biological treatment of synthetic wastewater containing 2,4 dichlorophenol (DCP) in an activated sludge unit

Chlorophenol compounds present in many chemical industry wastewaters are resistant to biological degradation because of the toxic effects of such compounds on microorganisms. Synthetic wastewater containing different concentrations of 2,4 dichlorophenol (DCP) was subjected to biological treatment in an activated sludge unit. Effects of feed DCP concentration on COD, DCP, and toxicity removals and on sludge volume index were investigated at a constant sludge age of 10 days and hydraulic residence time (HRT) of 25 h. The Resazurin method based on dehydrogenase activity was used for assessment of toxicity for the feed and effluent wastewater. Percent COD, DCP, and toxicity removals decreased and the effluent COD, DCP, and toxicity levels increased with increasing feed DCP concentrations above 150 mgl(-1) because of inhibitory effects of DCP. Biomass concentration in the aeration tank decreased and the sludge volume index (SVI) increased with feed DCP concentrations above 150 mgl(-1) resulting in lower COD and DCP removal rates. The system should be operated at feed DCP concentrations of less than 150 mgl(-1) in order to obtain high COD, DCP, and toxicity removals.     

城镇污水处理厂项目环境影响评价中的重点分析

根据城镇污水处理厂项目的特点,对此类项目环境影响评价中的厂址选择、处理规模及进出水水质的确定以及地表水、恶臭环境影响预测及二次污染控制、污泥处置方案的可行性论证等重点内容进行了分析。     

A modified anaerobic baffled reactor for municipal wastewater treatment

A nine-chambered modified anaerobic baffled reactor (MABR) was developed to evaluate its suitability for the treatment of municipal wastewater and to establish the understanding of the relationship between reactor design and operational parameters. The paper presents the configuration of the MABR, its start-up, effect of variation of hydraulic retention time (HRT) on treatment efficiency, and performance evaluation of the MABR while treating the municipal wastewater. To assess the self-inoculation potential of the MABR, the start-up was carried out without seed sludge at a HRT of 6 d.     

三维电极法处理废水的研究进展

传统二维电极面体比小、电流效率低、能耗高等不足而制约了其降解废水的实际应用。三维电极相对于二维电极来说,具有面体比大、离子间距小、传质效果好等优势,因而在降解废水中得到了广泛应用。本文介绍了三维电极的分类、制备方法和载体种类,并对三维电极电催化废水的研究进行了简单的综述。阐述了三维电极在处理废水中的电化学催化机理,同时对三维电极所面临的急需解决的问题和发展趋势作了简要的分析。     

市政污泥与高浓度废弃物的厌氧共消化：一种生物质能源净产生的途径

厌氧共消化是一种绿色、实用的回收废弃物中能源的技术。本文介绍了厌氧共消化技术的原理，并介绍了美国佐治亚州F. Wayne Hil水资源处理中心采用油脂废弃物（FOG）和含糖工业废水与市政污泥进行连续流厌氧共消化的实际应用案例。结果表明，厌氧共消化可显著提高甲烷产量达2倍以上，甲烷产量随着高浓度有机废弃物负荷率及厌氧消化反应器停留时间的延长而增加，且COD和VS降解率可保持在合理范围内，经济效益显著。     

化学合成类制药废水处理工程的工艺设计

根据化学合成类制药废水高盐分、难降解、高浓度的特点,提出了"废水分质分流,物化+生化"的处理思路。高浓度工艺废水经二级氧化处理后再与低浓度废水混合,进入生化处理工艺流程。物化采用"多维电催化+高效微电解"的二级高级氧化处理,生化段采用"UASB厌氧+水解+好氧"的处理工艺。这种联合处理工艺具有处理效果稳定、占地面积小、运行成本较低的特点,废水处理后达到工业园区污水厂接管标准后接入污水管网。     

Performance of an overland flow system for advanced treatment of wastewater plant effluent

Overland flow (OF) systems were evaluated and compared for advanced treatment of municipal and industrial effluents, including nutrients and nondegradable chemical oxygen demand (COD) removal. Three pilot plants were constructed at the Shahin Shahr Wastewater Treatment Plant (WWTP), Isfahan, Iran. Each pilot was assigned a specific wastewater and all were simultaneously operated for 8 months. Treatment of primary effluent, activated sludge secondary effluent, and lagoon effluent of textile wastewater was investigated at application rates (ARs) of 0.15, 0.25, and 0.35m(3)m(-1)h(-1). During 5 months of stable operation after a 3-month acclimation period, mean removals of total 5-day biochemical oxygen demand (TBOD(5)), total COD (TCOD), total suspended solids (TSS), total nitrogen (TN), total phosphorus (TP) and turbidity were 74.5%, 54.8%, 66.2%, 39.4%, 35.8%, and 67.7% for primary effluent; 52.9%, 52.9%, 66.5%, 44.4%, 39.8%, and 50.1% for activated sludge effluent; 65.7%, 58.7%, 70.3%, 41.7%, 41.3%, and 54.9% for textile wastewater lagoon effluent, respectively. The model of Smith and Schroeder, 1985. Field studies of the overland flow process for the treatment of raw and primary treated municipal wastewater. Journal of Water Pollution Control Federation 57, 785-794] was satisfactory for TBOD(5). For all treatment parameters a standard first-order removal model was inadequate to represent the data but a modified first-order model provided a satisfactory fit to the data. Based on the results of this study, it can be concluded that an OF system as advanced treatment had the ability to meet effluent discharge permit limits and was an economical replacement for stabilization ponds and mechanical treatment options.     

城市污水处理技术探讨

本文对城市污水处理技术进行了分类分析综述,阐明了当前污水技术发展趋势及应用情况。也对随着经济发展我国水处理标准制订的演变进行了说明。论述了现有城市污水处理厂工艺适扩和投资背景。     

Wastewater treatment with multilayer media of waste and natural indigenous materials

Wastewater treatment using waste materials (refuse concrete, waste paper and charcoal) and natural indigenous rocks (andesite, limestone, granite and nitrolite) in the form of multilayer media was investigated. The removal of suspended solids (SS), phosphate ion, nitrate ion, ammonium ion, toxic metals and chemical oxygen demand (COD) were evaluated for the multilayer wastewater treatment system. Effective removal of heavy metals such as cadmium, chromium, mercury and lead was demonstrated. SS and phosphate ion were removed with relatively high efficiency and the COD after treatment was lessened using certain combinations of media. The present wastewater treatment system is simple, convenient and low cost. Therefore, this method can be applied in small scale plants for wastewater treatment in local and nonexclusive areas.     

Use of toxicity identification evaluation techniques to identify dredged material disposal options: A proposed approach

It is common to use the results of various solid-phase and aqueous-fraction toxicity tests as part of the decision-making process for selecting disposal options for dredged sediments. The mere presence of toxicity, however, does not provide a logical basis for selecting economical, environmentally protective disposal techniques. To achieve this, it is necessary to be able to identify specific compounds responsible for sediment toxicity. Toxicity identification evaluation (TIE) procedures, originally developed for complex effluents, represent a useful approach for identifying acutely toxic compounds in dredged materials. Herein we present a conceptual overview for TIE use in part of the decision-making framework for selecting dredged material disposal options; included are discussions concerning appropriate test fractions and species for TIE analyses, and specific TIE manipulations useful for ascertaining whether toxicity is due to any of a number of common sediment contaminants including ammonia, hydrogen sulfide, metals, or nonpolar organics.     

基于EBM模型的长江经济带工业用水效率时空差异及影响因素分析

工业化进程的加快使得工业水资源需求不断增加，工业废水排放量也越来越大，如何提高工业用水效率从而缓解水资源压力成为日益严峻的问题。本文选取工业用水量、工业就业人数、工业固定资本和工业废水治理费用作为投入指标，以工业增加值与工业废水排放量作为期望与非期望产出指标。首先利用EBM模型计算长江经济带2008—2017年工业用水效率，其次利用泰尔指数来分析工业用水效率的区域差距，最后利用面板Tobit模型来分析影响不同地区工业用水效率的驱动因素。结果显示，近年来长江经济带的工业用水效率呈波动下降趋势，不同地区效率差异明显；经济发展水平、工业化程度、技术水平、水资源禀赋和政府环境管制力度对长江经济带的工业用水效率都有一定影响，但存在地区差异。     

硫磺回收装置脱硫废液处理的试验研究

采用将脱硫废液与炼油废水按比例混合之后对其进行处理的方法,通过批式试验,考查混合废液的BOD5/COD指标及其COD、NH3-N、S2-的去除率。筛选合适的混合液配比,分别对500︰1和800︰1的混合废液进行了模型试验,分析了COD去除效果。结果表明:800︰1的混合废液在10d之后,出水COD为134mg/L,达到了《污水综合排放标准》(GB8978—1996)二级标准要求。最终确定炼油废水与脱硫废液混合的合适比例应不低于800︰1。