贵州省城市污泥重金属组成特征与农用风险评价

分别选取了贵州省7个主要城市的10个典型污水处理厂脱水污泥样品进行检测,统计了2009~2012年污泥中重金属Cu、Zn、Pb、Cd、Ni、Cr、As、Hg的含量。结果表明,城市污泥中重金属含量受到各地区工矿业发展的影响,部分重金属在某一污水处理厂出现了远大于其它地区的极值,具有明显的地域特征。2009~2012年贵州省城市污泥重金属的变化表现为As、Hg呈升高趋势,其它重金属变化趋势不明显,As、Hg升高可能是因为贵州省近年来燃煤消耗量增加,烟气排放污染所致。对污泥重金属的农用风险评价显示,贵阳中部（S2）、黔西地区(S9)污泥农用重金属的生态风险较高,不推荐直接施用,其它各地区污泥农用风险较低,可以进行农用,建议各污水处理厂应根据本地区污泥重金属特征制定合理的污泥处置措施     

关于纺织印染行业环保治理和建设生态工业园的设想

污染治理问题已成为制约纺织行业发展的一个主要因素,本文基于实践经验总结提出纺织行业集中建设生态工业园的设想,即围绕纺织印染企业,集中配套建设热电厂、净水厂、污水厂和污泥热干化处理中心,生态工业园主要实现以下功能:(1)园区企业产生的污染物在园区内消纳,不产生二次污染,包括印染废水集中处理和综合利用、废气集中处理,印染污泥减量化、稳定化、无害化和资源化处置;(2)利用供热锅炉、废水、废气、污泥等污染物处理设施集中建设的特点,在园区内实现余热蒸汽、水、污泥等资源的梯级利用和回用,减少印染企业能源消耗和污染治理成本;(3)园区内水、气、污泥等环保处理设施相互利用,避免重复建设和分散建设,减少管理成本和固定资产投入。通过行业生态工业园的建设,以期解决纺织行业中高能耗重污染企业面临的污染治理压力,避免产业转移产生污染转移问题,为中国纺织行业产业链完整性和污染物有效控制提供一种解决思路。     

江苏省化工园区污水处理厂污泥重金属污染及生态风险评价

污水处理厂的排放污泥是诸多污染物的最终环境归宿之一,其环境影响值得重视。在江苏省全境调查了49家化工园区集中式污水处理厂,对其外排污泥及其浸出液中的5种重金属(砷、镉、铬、汞和铅)含量进行了测定,采用Hakanson潜在生态危害指数法评价了污泥中重金属生态风险。结果表明:49家化工园区污泥浸出液中5种重金属均不超标,但污泥中的砷、铬、汞含量超标,超标率分别为24.5%、6.1%和4.1%,最大超标倍数分别为131、2.12和0.41。污泥中砷含量显著高于我国城市污泥,潜在生态风险程度呈现汞砷铬。从地域分布来看,苏北地区化工园区污泥重金属风险更大。     

金坛市饮用水源地保护方案研究

:钱资荡是金坛市目前直接饮用水源地 ,根据环境环境监测结果 ,已处于中营养化后期。本文借鉴国内外先进的湖泊管理的成功经验 ,运用系统工程的思想和方法提出了切实可行的金坛市饮用水源地保护方案。该方案由 4个工程子系统组成 ,(1)截污工程 :在岸丘桥和南州桥位置各筑一节制闸 (而岸丘桥工程又是首选工程 ) ,以封住湖泊两头入流 ,杜绝污染物进入水源地的截污工程 ;(2 )引水工程 :是截污工程的配套工程 ,利用下游长荡湖来补充水量 ,并对 3个引水工程设想进行了系统分析 ,推荐涵管方案 ,同时将长荡湖作为该市战略水源地一并纳入保护体系中 ;(3)湿地生态处理工程 :对进入荡区前的芦苇区进行综合整治 ,发展以芦苇为主的湿地生态处理工程 ;(4 )环湖绿色自然保护带工程 :包括建设围湖芦苇荡、环湖林带、绿色食品基地以及污泥处置。最后还提出了三级水域保护区范围、水域行政管理体系建设以及工程方案分步实施计划     

金坛市饮用水源地保护方案研究

钱资荡是金坛市目前直接饮用水源地,根据环境监测结果,它已处于中营养化后期。借鉴国内外先进的湖泊管理经验,运用系统工程的思想和方法提出了切实可行的金坛市饮用水源地保护方案。该方案由4个工程子系统组成,（1）截污工程：在岸丘桥和南州桥位置各筑一节制闸（而岸丘桥工程又是首选工程）,以封住湖泊两头入流,杜绝污染物进入水源地的截污工程;（2）引水工程：是截污工程的配套工程,利用一游长荡 湖来补充水量,并对3个引水工程设想进行了系统分析,推荐涵管方案,同时将长荡湖作为该市战略水源地一并纳入保护体系中;（3）湿地生态处理工程：对进入荡区前的芦苇区进行综合整治,发展以芦苇为主的湿地生态处理工程;（4）环湖绿色自然保护带工程：包括建设围湖芦苇荡、环湖林带、绿色食品基地以及污泥处置。最后还提出了三级水域保护区范围、水域行政管理体系建设以及工程方案分步实施计划。     

污水处理厂的"二次污染"不可忽视

污水处理厂是减少水体污染的一个重要关口 ,但是由于技术的局限 ,它在处理污水的同时 ,自身也会产生污泥和其他废弃物 ,如果处理不当 ,也会对水体和土壤造成“二次污染”。在上海举办的首届“中国国际环保、能源和资源综合利用博览会”上 ,上海市排水管理处副总工程师唐建国指出 ,上海市区现共有污水处理厂 3 4座 ,每天污水处理过程中产生的污泥总量约在 10 0 0立方米 ,到 2 0 0 5年 ,预计每天将产生 40 0 0立方米的污泥。目前 ,上海污水处理过程中产生的污泥 ,除个别污水处理厂经过了厌氧消化稳定 ,绝大部分污泥仅做到了浓缩和机械脱水 ,因…     

中国风电产业供需环境分析与发展预测

本文利用波特五力模型对中国风电产业所处竞争环境进行分析,认为中国风电产业内部竞争激烈,外来威胁不明显,替代品威胁力较弱,产业链上游核心零部件生产呈现"技术空心化"。通过对"风电零部件供给-风电整机制造-风电场运营开发"整个风电供需链的分析,认为现阶段制约我国风电产业持续发展的最大障碍,并不在于风电的制造、生产和运营,而是受制于风电并网的约束。为进一步研究未来我国风电市场的发展趋势,本文基于预测效果优于BP神经网络的STA-LSSVM模型,利用1993-2011年中国风电装机新增容量、累计容量及风电并网新增容量、并网累计容量等数据,预测了风电生产供给与风电并网需求的发展趋势。结果显示,2012-2015年我国风电装机容量增长率逐年上升趋势明显,而风电并网容量增长率则趋于平缓。预计到2014年风电累计并网容量缺口将达到4 817.03 MW,需求缺口将愈来愈大,风电消纳远远滞后于风电生产,风电产能"相对过剩"的局面将更加严重。鉴于此,本文在政策层面上给出如下建议:(1)进一步加强国家电网建设。要有重点、分步骤地建设偏远地区电网设施,并建立更大区域的电力市场,在区域电网内甚至在区域电网外寻找风电消纳市场;(2)创新风电并网技术及应用。政府应积极支持风电开发和并入电网所需要的输电投资;(3)加强风电项目风险控制。国家电力监管部门要重视风电场与电网的相互影响,加强监管力度;(4)创新风电利用方式。通过开发供热、农业提水灌溉等灵活用电负荷,促进风电就地消纳和利用。     

三峡库区危险工业废物的现状及清理处置分析

目前，三峡库区沿江堆存有大量的危险废物，这对蓄水在即的长江三峡水利枢纽工程极具威胁，对库区生态环境，水资源及人群的身心健康有潜在的危害性，必须进行全部清理处置。库区堆存的危险废物近1．5万t，种类多，成分复杂，毒性大，清理处置困难。分析了典型危险废物的危害性，同时根据三峡库区库底废物清库要求和规范，结合库区实际情况，提出库区库底堆存危险废物的清理处置方案：危险废物中约578t可进行化学中和稳定化处理，焚烧处理，综合利用等无害化处理，其余不能进行无害化处理的危险废物，在坝前177m水位以上选择合理的地点进行安全，可靠的临时贮存处置，待库区危险废物处理处置中心建成后再进行最终的处理处置。     

突发水污染事故风险评估体系的研究现状与问题

本文对我国突发水污染的致因及其风险评估体系的研究现状进行了述评,指出了目前风险评估体系在事故发生前的预判性、与应急处置难度的关联性以及对处置结果的后续影响的兼顾性等方面的不足,并对相关领域可借鉴的研究技术方法进行了综述,为完善我国突发水污染风险评估体系提出了建设性意见。     

关于青岛市废旧电器循环利用对策的思考

随着科技的不断进步，家电产品更新换代的速度不断加快，由于废旧电器的不当处置所引发的环境问题日益突出。如何在保障环境安全的前提下，建立有效的废旧电器回收体系，实现废旧电器的资源最大化和环境无害化处置是当前我国大力发展循环经济主要面对和重点要解决的问题之一。本文以青岛市电器产品的生产和保有状况、废旧电器排放和资源化利用状况调查为基础，分析了静脉产业类生态工业园区的建设对促进废旧电器“3R”化的重要作用。揭示了建立合理的回收体系是青岛市废旧电器循环利用的主要因素。结合“延伸生产者责任制度”，提出青岛市废旧电器循环利用的对策及各相关方责任。为青岛市制订废旧电器相关地方性法规提供了重要依据，同时也为国家相关立法工作提供了重要借鉴。     

Mechanical performance and capillary water absorption of sewage sludge ash concrete (SSAC)

Disposal of sewage sludge from waste water treatment plants is a serious environmental problem of increasing magnitude. Waste water treatment generates as much as 70 g of dry solids per capita per day. Although one of the disposal solutions for this waste is through incineration, still almost 30% of sludge solids remain as ash. This paper presents results related to reuse of sewage sludge ash in concrete. The sludge was characterised for chemical composition (X-ray flourescence analysis), crystalline phases (X-ray diffraction analysis) and pozzolanic activity. The effects of incineration on crystal phases of the dry sludge were investigated. Two water/cement (W/C) ratios (0.55 and 0.45) and three sludge ash percentages (5%, 10% and 20%) per cement mass were used as filler. The mechanical performance of sewage sludge ash concrete (SSAC) at different curing ages (3, 7, 28 and 90 days) was assessed by means of mechanical tests and capillary water absorption. Results show that sewage sludge ash leads to a reduction in density and mechanical strength and to an increase in capillary water absorption. Results also show that SSAC with 20% of sewage sludge ash and W/C = 0.45 has a 28 day compressive strength of almost 30 MPa. SSAC with a sludge ash contents of 5% and 10% has the same capillary water absorption coefficient as the control concrete; as for the concrete mixtures with 20% sludge ash content, the capillary water absorption is higher but in line with C20/25 strength class concretes performance.     

Nonylphenol in the environment: a critical review on occurrence, fate, toxicity and treatment in wastewaters

Nonylphenol is a toxic xenobiotic compound classified as an endocrine disrupter capable of interfering with the hormonal system of numerous organisms. It originates principally from the degradation of nonylphenol ethoxylates which are widely used as industrial surfactants. Nonylphenol ethoxylates reach sewage treatment works in substantial quantities where they biodegrade into several by-products including nonylphenol. Due to its physical-chemical characteristics, such as low solubility and high hydrophobicity, nonylphenol accumulates in environmental compartments that are characterised by high organic content, typically sewage sludge and river sediments, where it persists. The occurrence of nonylphenol in the environment is clearly correlated with anthropogenic activities such as wastewater treatment, landfilling and sewage sludge recycling. Nonylphenol is found often in matrices such as sewage sludge, effluents from sewage treatment works, river water and sediments, soil and groundwater. The impacts of nonylphenol in the environment include feminization of aquatic organisms, decrease in male fertility and the survival of juveniles at concentrations as low as 8.2 mug/l. Due to the harmful effects of the degradation products of nonylphenol ethoxylates in the environment, the use and production of such compounds have been banned in EU countries and strictly monitored in many other countries such as Canada and Japan. Although it has been shown that the concentration of nonylphenol in the environment is decreasing, it is still found at concentrations of 4.1 mug/l in river waters and 1 mg/kg in sediments. Nonylphenol has been referred to in the list of priority substances in the Water Frame Directive and in the 3rd draft Working Document on Sludge of the EU. Consequently there is currently a concern within some industries about the possibility of future regulations that may impose the removal of trace contaminants from contaminated effluents. The significance of upgrading sewage treatment works with advanced treatment technologies for removal of trace contaminants is discussed.     

Fate, behavior and effects of surfactants and their degradation products in the environment

Surfactants are widely used in household and industrial products. After use, surfactants as well as their products are mainly discharged into sewage treatment plants and then dispersed into the environment through effluent discharge into surface waters and sludge disposal on lands. Surfactants have different behavior and fate in the environment. Nonionic and cationic surfactants had much higher sorption on soil and sediment than anionic surfactants such as LAS. Most surfactants can be degraded by microbes in the environment although some surfactants such as LAS and DTDMAC as well as alkylphenols may be persistent under anaerobic conditions. LAS were found to degrade in sludge amended soils with a half-lives of 7 to 33 days. Most surfactants are not acutely toxic to organisms at environmental concentrations and aquatic chronic toxicity of surfactants occurred at concentrations usually greater than 0.1 mg/L. However, alkylphenols have shown to be capable of inducing the production of vitellogenin in male fish at a concentration as low as 5 microg/L. More toxicity data are needed to assess the effects on terrestrial organisms such as plants.     

Selection of an effective sludge dewatering system for a small wastewater treatment plant

The Jahra Plant was commissioned in 1981 as a secondary treatment plant employing the extended aeration process. The plant has been upgraded since that time by constructing additional tertiary filtration units to improve effluent quality. The plant has a design capacity of 66 000 m³/d. At present, the daily inflow to the plant is about 47 000 m³/d of domestic sewage. The sludge produced at the Jahra Plant can be classified as excess activated sludge which combines the primary and secondary solids. At present, there are 30 drying beds receiving about 100 m³ of sludge dally. Sewage-sludge production represents about 0.5% of the total flow treated at the plant and is increasing yearly with increases in population and water consumption. Present dewatering systems are not adequate to cope with expansion in sewage treatment. Increasing the capacity of the existing plant would require more drying beds that could exacerbate existing odor problems. Some dewatering systems, such as the belt filter press and the centrifuge, have been tested to determine the most effective one under local conditions. Appropriate polymer doses for thickening have been determined. This paper describes present sludge dewatering units and operating techniques which have been developed during the operation of this facility.     

Assessment of polychlorinated dibenzo-p-dioxins and dibenzofurans in sludges according to the European environmental policy

The amount of sewage sludge generated in Europe is expected to surpass the 10 million tons/year in 2006 as a result of the waste water treatment process according to the Water Policy in European Union. Sewage sludge is what is left behind after water is cleaned in waste treatment plants and is characterized for this high content in nitrogen and phosphorous that could be of great importance in agriculture as fertilizer or soil conditioner. On the other hand, pollutants like metals and organic contaminants are usually removed from water and are accumulated in the sewage sludge, reaching the food chain if their concentrations are not below the safe limits established by the European legislation. The latter issue is of great concern nowadays and in this sense, different works alert against the use of the sewage sludge in agriculture arguing that serious illnesses, even resulting in death as well as adverse environmental impacts are associated to the application of sewage sludge. This work is a continuation of a former comprehensive survey on of priority organic pollutant in sludges for agricultural purposes carried out by our group in Catalonia and this time is focused on the polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), one of the most toxic group of organic compounds listed in the Work Document on Sludge which is the reference tool in this field in Europe and is also included in the Stockholm Convention. Eighty eight samples were collected from the end of 2003 to April 2006 and the concentrations detected were lower than the 100 ng/kg I-TEQ limit recommended by the European legislation (EC, 2000). Thus, sewage sludges generated in Catalonia do not represent a threat to human health if they are used as fertilizers in agriculture.     

污水处理生物技术的应用

针对环保要求日益严格，而水源污染却越演越烈的现象，选择性地综述了湿地工艺、固定化藻类和活性污泥等生物技术在污水处理中的应用实例及其在净化废水、减轻水体富营养化方面的显著作用。三项生物技术的共同特点是高效快速、低耗节能、简易实用、管理方便且能耐受高负荷污水的冲击。净化污水主要通过基质的过滤吸附、微生物的分解代谢、植物根系或藻类的吸收利用等理化和生物的协同作用。确保和提高污水净化效果的关键因素是：湿地系统——水力负荷与停留时间、有机污染物负荷、根系发达的植物种类；固定化藻类——载体的传导性能和孔径、校固定藻类的细胞粒径、密度和生长状态、藻类生长的最适pH和温度条件；活性污泥技术——单位体积内好气性微生物的浓度及其与其他活性生物的比例、活性污泥的循环速度与回用、系统中的溶氧浓度和好气条件。     

The influence of zeolite type A on heavy metal transfer in the activated sludge process

In areas which are highly urbanised, where water re-use is frequently necessary, the importance of “heavy metal” removal during sewage treatment cannot be overestimated. One critical factor controlling the forms of the metals in the sewage is the chemical matrix of the sewage; as a consequence of their chelating capacity detergent builders are important in modifying the sewage matrix. Laboratory simulations of the activated sludge process have been studied to estimate the impact of the detergent builder zeolite type A on the removal of heavy metals from sewage in this treatment process.Experiments have also been undertaken in which the influent concentrations of the builder were doubled, in an endevour to simulate the effect of a “wash day”. It is apparent from the data presented that under conditions of constant loading, zeolite type A did not significantly affect the concentrations of any of the metals studied with the exception of zinc. However, removal of some of the metals was less than in the presence of a condensed phosphate solution. Under conditions of shock loading the improvement in metal removal which has been observed when condensed phosphates were added under conditions o of variable loading was not observed when zeolite type A was added under similar conditions.