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城市污水污泥资源化利用研究 总被引:1,自引:0,他引:1
为确定城市污水的污泥在农用过程中是否存在重金属毒害,文章系统研究了西宁城市污水的污泥中重金属特征。研究表明:①西宁城市污水的污泥中重金属含量较我国其他城市略低;②EDTA(乙二胺四乙酸)提取污泥时,重金属的提取率在18%-55%,这部分重金属有可能被植物吸收。③污泥中所含的有机质、氮、磷、钾微量元素及土壤改良剂(有机腐殖质)等成分可以改善土壤结构,提高土壤的肥力。 相似文献
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《四川环境》2019,(6)
为了解工业园区周边土壤重金属污染状况,选取园区周边12个采样点,测定土壤样品中重金属含量,采用地累积指数法和潜在生态风险对土壤重金属污染现状进行了评价。结果显示,园区周边土壤重金属平均含量高于背景值(除Cu和Ni),Hg、Pb、Zn最多超出背景值4.040、3.005、3.900倍。部分点位Pb和Zn含量超超过国家土壤环境质量标准限值。地累积指数法表明,园区Hg、Pb、Zn的多数点位介于中度污染和重度污染水平之间,部分点位处于重度以上污染水平,其余重金属多为中度及以下污染水平。潜在生态风险评价表明,单个金属生态风险程度为:HgCdPbAsZnNiCuCr。由于Hg和Cd元素的毒性系数较大,潜在的生态危害的可能也较大,其余6种重金属均处于轻微低风险级别。整体的潜在生态风险来看,工业园区周边土壤多数处于中等风险级别状态。可见,工业园区周边土壤整体状况较差,存在中等的潜在生态危害。 相似文献
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《四川环境》2017,(3)
为了解泸州市蔬菜种植地土壤重金属的污染状况,分析了泸州市蔬菜地土壤中的p H值、有机质以及重金属(Cd、Hg、As、Pb、Cr、Cu)含量,并用单因子污染指数法、综合污染指数法、地积累指数法以及潜在生态危害指数法对该地区土壤重金属污染状况以及生态风险进行评价。结果表明,该地区土壤中Cd、Hg、As、Pb、Cr、Cu的平均含量水平未超过四川土壤背景值土壤。利用农业行业标准(NY/T391-2000)中土壤污染元素的浓度限值进行评价,泸州市蔬菜种植地土壤重金属均未超标。地积累指数及潜在生态危害综合指数评价结果表明,泸州市蔬菜种植地土壤中重金属污染处于轻微污染或无污染以及轻微的潜在生态风险水平,Cd的潜在生态危害系数最高,贡献最大。 相似文献
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通过对钒钛磁铁矿尾矿库周边农用土壤的采样调查,测定了6种重金属(Cr、Ni、Pb、Cd、Hg、As)的含量,并采用单因子污染指数法、内梅罗综合污染指数法和潜在生态危害指数法探讨了研究区土壤重金属的污染程度。结果表明:研究区土壤中的重金属含量均未超过GB15618-2018风险筛选值,但Cr、Ni、Cd、Hg等重金属平均值高于四川省土壤环境背景值;评价显示土壤中各采样点的重金属单因子污染指数均小于1,内梅罗污染指数均小于0.7,说明各监测区域土壤环境质量处于清洁水平;从潜在生态风险指数评价结果来看,尾矿库周边农用地各重金属潜在生态风险程度强弱顺序为Hg>Cd>As>Ni>Pb>Cr,研究区整体处于中等生态危害。 相似文献
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动电技术去除城市污泥中重金属的可行性探讨 总被引:3,自引:0,他引:3
本文简要介绍了我国城市污泥的处理处置和利用现状及动电技术去除重金属的基本原理,分析动电技术处理土壤中重金属的国内外的试验研究和应用情况,对动电技术处理城市污泥中重金属的可行性进行探讨,认为动电技术去除城市污泥中的重金属具有可行性,并提出了今后研究的方向. 相似文献
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用污水污泥生产生物炭并应用于土壤改良,是一种经济有效的土壤修复方法,具有提高土壤肥力、固定重金属、增加土壤生物量等效果。为了深入评估污水污泥基生物炭在土壤应用中的可行性,论述了污泥生物炭的制备方法与性质,探讨了污泥生物炭施入土壤后对土壤理化性质、重金属污染及有机物污染等方面的作用,分析了污泥生物炭作为土壤改良剂的可行性和潜在的危险,并对污泥生物炭研究与应用的方向进行了展望,对促进污泥资源化利用和土壤修复具有现实意义。 相似文献
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城市道路两侧土壤重金属分布特征及生态风险评价 总被引:1,自引:0,他引:1
通过采集吕梁市G209线公路两侧土壤,研究土壤中锌、铜、镍、铅4种重金属的分布特征,并采用单因子污染指数法和内梅罗综合指数法进行生态风险评价。结果表明:采样点距离公路直线距离越大,土壤中重金属含量越低,且主要富集在0~20m可耕层,表现出明显的垂直递减规律。土壤重金属污染程度为:Pb(中度污染)>Cu(轻微污染)>Ni(轻微污染)>Zn(未污染),生态风险评价等级为Ⅴ,属于重污染。汽车尾气的排放是主要污染来源,对于农业用地,农药、化肥的施用也是主要污染源。 相似文献
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Mohammad Khan Jamali Tasneem Gul Kazi Mohammad Bilal Arain Hassan Imran Afridi Nusrat Jalbani Jameel A. Baig Abdul Niaz 《The Environmentalist》2008,28(4):366-375
The recycling of sewage sludge on agriculture land represents an alternative, advantageous, disposal of this waste material.
The aim of the present study was to evaluate the feasibility of using industrial sewage sludge, produced in Pakistan, as a
fertiliser. Agricultural soil amended with 25% (w/w) sewage sludge with or without lime treatment was used for growing a variety
of sorghum (PARC-SS-1). The mobility of the heavy metals (HMs) (Cd, Cu, Cr, Ni, Pb and Zn) and metalloid (As) in the untreated
industrial waste water sewage sludge (UIWS) samples were assessed by applying a modified BCR (Community Bureau of Reference)
sequential extraction procedure. The single extraction procedure comprised of the application of mild extractant (CaCl2) and water for the estimation of the proportion of easily soluble metal fractions. The precision and accuracy of BCR was
evaluated by using a certified reference material of soil amended with sewage sludge BCR 483. The plant available metal contents,
as extracted by the deionised water and 0.01 M CaCl2 solution and exchangeable fraction of BCR sequential, decreased with lime application in the range of 10–44% for As, Cr,
Ni, Pb and Zn, except in the cases of Cd and Cu, where their mobility was increased by 10% and 24%, respectively. Sludge amendment
enhanced the dry weight yield of sorghum and the increase was more obvious after liming up to 25%. The uptake of HMs were
lower in test samples (3.2–21.8%), except for Cu and Cd, which was higher (4%), while they were below the permissible limit
of these metals. The present experiment demonstrates that liming was important in factors facilitating the growth of sorghum
in sludge-amended soil. 相似文献
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超声波去除农用污泥中重金属的试验研究 总被引:1,自引:0,他引:1
污水处理厂污泥中的重金属浓度高是污泥农用的主要障碍。为了降低农用污泥中的重金属含量,以Cu、Zn、Ni、Pb为对象,研究了超声波对其的影响。结果表明:超声对污泥中重金属有一定的溶出作用。当超声时间为30min时,溶解状态Cu、Zn、Ni、Pb的析出率分别为42.1%、37.5%、12.7%、14.7%;总的析出率分别为52.7%、44.7%、23.6%、71%。其中析出的Pb大部分以胶体状态存在,而溶解状态只占很少一部分。其他几种金属则以溶解状态为主。 相似文献
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污泥中重金属的稳定化研究进展与去除方法简述 总被引:1,自引:0,他引:1
通过"十一五"污水处理厂的建设,我国污泥产量也随之大幅增长,污泥的处理处置已经成为制约社会经济发展的重要问题。国际上的经验表明土地利用是污泥最终处置的主要发展方向,然而污泥中的重金属成为其土地利用的主要障碍。越来越多的研究者意识到,重金属的环境危害不仅仅取决于其总量,更取决于重金属存在形态。目前,Tessier分步提取法作为主流的污泥重金属划分方法,取得了广泛应用,该法将污泥中的重金属分成5种形态,分别为可交换态、碳酸盐结合态、铁锰氧化物结合态、有机结合态和残渣态。本文以此为基础综述了目前国内外主要的污泥重金属稳定和去除方法的原理及研究进展,比较了不同重金属稳定及去除方法的优点与不足,并提出了新的展望。 相似文献
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During the treatment of sewage, a huge volume of sludge is generated, which is disposed of on land as soil fertilizer/conditioner due to the presence of nitrogen, phosphorus, potassium and other nutrients. However, the presence of toxic heavy metals and other toxic compounds in the sludge restricts its use as a fertilizer. Over the years, bioleaching has been developed as an environmentally friendly and cost-effective technology for the removal of heavy metals from the sludge. The present paper gives an overview of the various bioleaching studies carried out in different modes of operation. The various important aspects such as pathogen destruction, odor reduction and metal recovery from acidic leachate also have been discussed. Further, a detailed discussion was made on the various technical problems associated with the bioleaching process, which need to be addressed while developing the process on a larger scale. 相似文献
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Use of metal-rich sewage sludge as soil fertilizer may result in trace- metal contamination of soils. This study was conducted to evaluate the effects of long-term sludge application on trace-metal (Zn, Cu, Pb, and Ni) distribution and potential bioavailability in Nigerian soils under a tropical wet-dry climate. Total metal analyses, sequential chemical fractionation, and DTPA extractions were carried out on samples of control and sludge-amended pedons in Nigeria (a Rhodic Kandiustult and two Rhodic Kandiustalfs from Nigeria, respectively). The sewage sludge applied to the soils contained higher levels of Zn and Cu than Pb and Ni. The control pedon contained low levels of all four metals. Soil enrichment factors (EF) were calculated for each metal in the sludge-amended pedons. Compared with the control soil, the sludge-amended pedons showed elevated levels of Zn and Cu, reflecting the trace-metal composition of the sewage sludge. Zinc and Cu in the sludge-amended soils were strongly enriched at all depths in the profile, indicating that they had moved below the zone of sludge application. The sequential extraction and DTPA analyses indicated that the sludge-amended soils contained more readily extractable and bioavailable metal ions than the unamended soil. 相似文献