动电技术去除城市污泥中重金属的研究概况

介绍了动电技术去除重金属的基本原理和常见的几种动电技术工艺,并总结了动电技术处理城市污泥中重金属的应用研究概况。     

不同固体浓度下不同菌去除重金属效果

在污泥中分别接种10％的氧化硫硫杆菌菌液与氧化亚铁硫杆菌菌液，研究了不同菌种情况下，10g／L到40g／L梯度的污泥浓度对生物淋滤重金属Zn和Cu的影响。实验表明，在不同固体浓度下两种菌对污泥中Zn和Cu的去除率都很高，污泥浓度越低，污泥中重金属的去除率越高。淋滤过程中，低固体浓度污泥，氮、磷、钾及有机质等营养物质流失量比高固体浓度污泥明显增多；而同浓度下，氧化硫硫杆菌在去除污泥中重金属的同时，营养物质的损失小于氧化亚铁硫杆菌。     

酸化污泥中重金属在电动力作用下的去除率研究

分析了长沙市某污水处理厂污泥中重金属分布.对污泥样品用HNO3进行酸化处理,酸化后pH值为3.2、1.9.分析了酸化处理后Cd、Zn、Cu在污泥中的形态分布.重点研究了酸化污泥中的Cd、Zn、Cu在电动力作用下的去除率.酸化污泥在电动力的作用下,经过5 d后,Cd、Zn的去除率明显提高,Cu的去除率提高相对较少.针对我国污泥中Zn含量较高的特点,提出在污泥厌氧消化处理时,同时用电动力处理污泥中的重金属,可大大提高重金属的去除率.     

混凝沉淀法去除水中六价铬、砷、汞的实验研究

随着工业的发展,重金属废水、废渣、污泥等污染永源,对人类产生的危害日益严重,日益引起人们的重视。研究和解决水中重金属的有效、实用的处理技术是非常必要的,目前尽管有许多处理重金属的方法,但用羟基氯化铝和明矾作为混凝剂来混凝沉淀去除水中重金属的报道不多。因此,为给消除水中的重金属提供依据,我们进行了如下研究。     

施用城市污泥对土壤中重金属积累和迁移的影响

目的 了解城市污泥农用后土壤重金属的积累和迁移。方法 于1998年分不同季节，从苏州、无锡、常州3个城市污水处理厂采集污泥样本，用原子吸收光谱仪分析样本中重金属(Pb、Zn、Cu、Cd、Hg、As)含量和不同形态含量，分析污泥农用后土壤重金属积累及迁移特性。结果 城市污泥重金属含量远高于土壤背景值，3城市污泥中Zn含量均超标，分别达到1199，00、784．00、1216．00mg／kg。长期施用能导致土壤重金属积累。污泥中重金属具有一定的活性和潜在迁移性。结论 城市污泥农用可能会导致土壤和生物体重金属积累，存在着一定的环境重金属积累风险。     

城市污泥中有害重金属检测与评估

城市污泥是活性污泥法处理城市生活污水和工业污水产生的固体废弃物,污水中50%～80%以上的重金属浓缩在产出的污泥中.Hg、Cd、Pb、Cr（Ⅵ）等重金属是我国第一批立法颁布的重点控制污染物,能在人体内长期积蓄并产生毒害.污泥中重金属的存在严重危害着包括人类在内的各种生命体的健康与生存,而且成为限制其资源化的主要障碍因素.本文从沈阳的污染状况出发,采用电感耦合等离子体质谱技术,对沈阳污水处理厂污泥中主要污染的重金属元素进行分析,以期为沈阳的环境质量评价和污染监控提供参考依据.     

混凝沉淀法去除水中六价铬

随着工业的不断发展,重金属废水、废渣、污泥等排于环境,污染水源,使水体重金属含量不断增加,对人类产生的危害日益严重。目前尽管有许多重金属处理方法,但用羟基氯化铝和明矾作为混凝剂来混凝沉淀去除水中重金属的报道为数还不多。因此,为了研究和解决水中重金属的有效、实用的处理技术,我们采用羟基氯化铝和明矾作为混凝剂,进行混凝沉淀去除水中六价铬、砷、汞的试验研究。首先在室温17℃、水温13℃,水pH7的条件下,选择出最佳混凝剂浓度。结果以每     

垃圾填埋场渗滤水预处理厂设计参数的调整

描述了美国东北部一个垃圾填埋场渗滤水预处理厂设计参数变化的情况.预处理是将渗滤水排入当地污水处理厂之前去除重金属(主要是铁、锰、锌)的过程.其主要反应是在一个加有石灰和凝聚剂的固体接触澄清器中进行,用来凝聚和沉淀重金属,而将澄清液进行中和之后排入下水道.富含重金属的污泥用压滤器脱水到45%,然后运去填埋.预处理厂于1988年底建成并顺利运转.文中提供了预处理厂的设计参数、渗滤水的成分及试验的可处理性,与污泥分级浸提毒性数据.     

动电技术修复城市污泥中重金属的研究

对动电技术的基本原理(包括电渗透、电迁移、扩散作用、电泳和电解反应)作了详细地介绍,分析了影响动电技术修复污泥中重金属的主要因素,包括电解液的组成和pH值、污泥性质、元素的化学性质和存在形态、电压、电流与电极等。探讨了动电技术修复污泥中重金属的可行性,并在此基础上对动电技术应用于修复污泥重金属的前景作出展望。     

不同钝化剂对污泥堆肥过程中重金属形态的影响研究

利用污泥和秸秆进行高温堆肥,研究粉煤灰、磷矿粉、沸石和草炭4种钝化剂对污泥堆肥中重金属（Cu、Zn、Pb、Cr）形态的影响。结果表明：堆肥过程中添加钝化剂可有效降低污泥中重金属有效态的含量,其中以粉煤灰的钝化效果最为显著。粉煤灰用于污泥堆肥不仅实现污泥的资源化,而且解决了粉煤灰的利用问题。     

Evaluation for Agricultural Usage with Speciation of Heavy Metals in a Municipal Sewage Sludge

This study was carried out to evaluate the agricultural usage of an anaerobically digested sludge in the contents and fractions of heavy metals. Therefore, a sequential extraction scheme according to the BCR's (Community Bureau of Reference) guidelines and total acid digestion were applied to sewage sludge samples. The results of total heavy metal concentrations in sewage sludge showed that the highest total concentrations were Fe, Zn and Mn. When Turkish, Europe and US EPA directives were compared with each other by depending on the use of sludge for agricultural purposes, all the heavy metals determined for this sludge were below the maximum permitted levels, except for Cd. This sludge should not be applied to land due to its high Cd content. The results of heavy metal fractions indicated that some metals (Cd, Mn, Pb, and Fe) distributed mainly in the residual fraction. All fractions of Zn showed no variation. Cu and Cr were most abundant in the oxidizable phase while Ni was in exchangeable phase. Although total content of Ni in the sludge is lower than the maximum levels allowed by all the directives, it tends to be easily moved and dispersed in the environment. Due to its high mobility, the examined sewage sludge may cause phyto-toxicity after its agricultural application.     

重金属的环境化学行为与毒理学研究

施用污泥及污水灌溉是造成土壤重金属污染的重要原因之一。随灌溉水进入土壤的重金属被吸附、固定在耕作层中，对土壤以及植物的生理性化和生长发育产生不良影响。因此应对重金属污染予以治理。     

Assessment of the environmental hazard from municipal and industrial wastewater treatment sludge by employing chemical and biological methods

Chemical analyses and toxicity testing were employed in conjunction to evaluate the environmental hazard from the wasted sludge generated during the biological treatment of urban and industrial wastewaters. Chemical analyses included determination of seven polychlorinated biphenyls (PCBs), 13 polycyclic aromatic hydrocarbons (PAHs), total organic carbon (TOC), and seven heavy metals (As, Cd, Cr, Cu, Pb, Mn, and Zn) in sludge and sludge leachates deriving from two standard leaching procedures: (a) the mild leaching test EN-12457-2 proposed by EC and (b) the relatively aggressive toxicity characteristic leaching procedure (TCLP) leaching test proposed by US EPA. Acute toxicity measurements were performed in aqueous sludge elutriates and leachates by using bioluminescence bacteria. The urban sludge was found to be more enriched with PAHs than the industrial sludge, however, at levels below the EU limits for sludge application. The total PCB content (Sigma7PCBs) in both sludges, particularly in the industrial sludge, exceeded the proposed European limit for sludge use as soil amendment. With regards to their heavy metal content, both sludges met the requirements for use in agriculture. The urban sludge exhibited high ecotoxicity, while the industrial sludge with almost two times lower toxicity was classified as not toxic to slightly toxic. The EN and the TCLP leaching procedures resulted in different sludge characterizations both from chemical and from ecotoxicological points of view. The EN procedure appeared to be more sensitive to the potential environmental risk from sludge disposal. The results of the study revealed the necessity for combining chemical with ecotoxicological criteria for integrated characterization of wasted sludge and the need for harmonization of the methods employed for waste classification.     

Analytical survey of elements and other constituents in Central New York state sewage sludges

Thirty-nine elements, polychlorinated biphenyls (PCBs), volatile N-nitrosamines and gamma emission were determined by several instrumental methods in sewage sludges from 24 communities in Central New York. Relatively high concentrations of certain elements or PCBs were found in sludges from specific communities. For example, antimony and certain rare earth elements used in glass manufacture were found at elevated levels in sludge from Corning, New York. Various volatile N-nitrosamines were found in all of the sludges in trace amounts. Gamma emission levels were relatively low in all sludges. One-third of the sludges would be classified as unsuitable for agricultural land application based on presently suggested federal guidelines for acceptable heavy metal or PCB concentrations in sludges. The question of the application of sludge to agricultural land is discussed.     

城市污泥重金属监测控制

分析了城市污泥的污染特性和其对生态环境的影响与危害。利用扫描电镜，x荧光分析仪，原子吸收光谱等现代分析技术对上海某城市污水处理厂污泥中复杂的化合物的形貌及无机化合物的物种进行了综合分析，确定了痕量重金属的存在状态，为控制、处理和资源化污泥提供理论依据。     

Environmental problems from the disposal of sewage sludge in Greece

The current situation on the quantities and disposal methods of sewage sludge in European Union is discussed, together with the trends up to 2005 and the future sludge disposal possibilities. The problems relating to the methods currently used in Greece and the requirement for land suitable for the safe agricultural application of sewage sludge are evaluated. This concept will be important to the decision-makers for the purpose of the disposal of sewage sludge in the future. Soil measurements in lands used for sludge disposal in western and southern Greece show that some soils have been already polluted by heavy metals and should be abandoned while others need careful monitoring until their saturation.     

Reduction of mercury,copper, nickel,cadmium, and zinc levels in solution by competitive adsorption onto peanut hulls,and raw and aged bark

Summary The competitive adsorption of common heavy metal ions by peanut hulls, raw bark, and composted bark was studied. These solid wastes were found to adsorb significant amounts of one or more of the heavy metals (Hg, Cu, Ni, Cd, Zn) commonly found in municipal sludge and wastewater.     

矿化垃圾的重金属淋溶试验研究

通过土柱实验模拟矿化垃圾以及矿化垃圾与污泥混合物在淋溶条件下重金属的淋失情况,并利用污染综合指数法分析矿化垃圾中重金属迁移对地下水的影响.结果表明淋溶的不同阶段对地下水易造成污染的金属元素有所不同,需要分阶段进行监控.淋溶初期需监测[As]、[Cr]、[Co]、[Cu]和[Mn];淋溶中期需监测[Ni]和[Pb];淋溶末期需对[Fe]进行监测.综合污染指数评价表明矿化垃圾以及矿化垃圾与污泥混合土壤的淋溶液对地下水造成潜在污染的最关键因子为Mn,其次是Fe.     

自来水厂污泥的表征及其垃圾覆盖土可行性研究

对自来水厂污泥进行了较系统的试验研究,如浸出毒性实验、剪切试验、重金属含量的检测等,以及作为垃圾覆盖土的可行性。研究结果表明,自来水厂污泥在1～2kg／cm^3压力作用下,含水率从61．3％减少到46．3％,渗透系数达到10^-7cm／s,无渗透毒性。用该污泥作垃圾填埋场覆盖土的边坡稳定性能较好,基本上满足作为覆盖土的技术要求,使用后不会给垃圾渗滤液的处理增加负担。因此,以自来水厂污泥作为生活垃圾填埋场覆盖土。可同时解决平原型填埋场缺土和污泥的最终出路问题。