厌氧条件下硫酸盐对重金属形态的转化作用

对城市污水处理厂污泥厌氧消化过程中不同浓度的硫酸盐对铜、锌、镍三种重金属化学形态变化所起的作用进行了分析研究 .结果表明 ,硫酸盐的存在能够促进污泥中重金属向稳定的硫化物形态转变     

从下水污泥中回收重金属

在污水处理中,污泥富集了污水中绝大部分重金属,而在污泥消化时,它们又几乎全部以硫化物形态转入消化污泥,这给回收利用提供了可能性。以下两种方法,可供参考选择。 一、细菌浸出污泥中的重金属 氧化硫杆菌、氧化铁杆菌和氧化铁硫杆菌     

污水处理厂脱水污泥中重金属的形态分布特征研究

研究了污水处理厂脱水污泥中重金属的形态及总量分布特征,对所采集的活性污泥和消化污泥样品的分析结果表明,镉、铜、铁和锌的主要分布形态为可还原态,在活性污泥中分别占各自总量的48.67%、83.74%、87.21%和64.90%,在消化污泥中则分别占各自总量的37.62%、83.44%、65.99%和61.64%;铬主要以残渣态存在,在活性污泥和消化污泥中分别占其总量的85.83%和67.64%;活性污泥中锰主要以弱酸提取态和可还原态存在,分别占47.16%和44.69%,在消化污泥中则主要以弱酸提取态存在,占61.69%;铅的5种形态分布比较均衡。活性污泥中7种重金属的总量呈现铁>铜>锌>锰>铬>铅>镉的趋势;消化污泥中7种重金属的含量排序则为铁>锰>锌>铜>铬>铅>镉。活性污泥中7种重金属的总量均高于消化污泥。     

ATAD自热式污泥好氧消化技术对市政污泥的处理效果

文章从工艺原理、技术特点、经济参数等方面介绍了ATAD自热式污泥好氧消化技术。ATAD自热式污泥好氧消化技术处理的是经过浓缩的初沉、二沉或两者的混合污泥,国外有众多案例证明经ATAD自热式污泥好氧消化技术处理后污泥中挥发性有机质减量达50%～60%,实现污泥减量化、稳定化、无害化,在重金属不超标的前提下也可进一步资源化。为验证该技术对中国污泥的适用性,在某污水厂进行了中试,发现经ATAD自热式污泥好氧消化技术处理后中国的市政污泥也可取得明显的升温、减容效果。     

污泥处理现状及资源化利用研究综述

随着城市化进程推进,城镇工业及生活废水量逐年上升,随之而来的是产生大量污水污泥。污泥含有病原体、重金属元素等,其处置不当会对环境产生二次污染。对国内外污泥常规处理方法及固化技术、厌氧消化技术等进行了综述,总结了目前我国污泥处理方法,希望为淤泥处理的深入研究及探索资源化利用新方法提供思路。     

上海城市污水厂污泥的农用处置方法研究

历时一年的调查显示，上海11家城市污水厂的污泥中含有大量的植物养分，但是在某些时期重金属含量会超过国家《农用污泥质量标准》，为此采用生物法和化学法对污泥中的重金属进行了沥滤试验。沥滤7d后的结果表明，采用生物法双用浓H2SO4酸化具更好的滤除效果；在生物法沥滤重金属的过程中还具有酸化法所没有的泥消化功能。     

超声/碱预处理剩余污泥的中温厌氧消化效果

考察了超声/碱联合预处理对剩余污泥中温厌氧消化的影响,并与原污泥直接进行厌氧消化的效果进行了比较.试验结果表明,在高投配率(10%)下原污泥直接进行厌氧消化对有机物的去除率不高,经过超声/碱预处理后,消化过程中对TCOD的去除率提高了29.6%,单位污泥的日均产气量提高了67.9%,对VS和VSS的去除率分别提高了58.9%和28.6%.     

硫酸盐对重金属化学形态的转化作用

研究了污泥厌氧消化过程中硫酸盐对铜、锌、镍三种重金属化学形态变化所起的作用。结果表明，硫酸盐的存在能够促进重金属向稳定的硫化物形态转变。     

北方地区污泥厌氧消化工艺应用现状分析

通过对我国北方地区108座大型污水处理厂污泥处理工艺的调研,总结了污泥厌氧消化工艺在我国北方大型污水处理厂的应用现状.结果显示,在108座污水处理厂中,共有27座采用厌氧消化工艺,其中具有代表性的9座污水厂中仅有3座正常运行.针对采用污泥厌氧消化工艺的污水处理厂,分别从工艺类型、污泥泥质、消化池池型、污泥搅拌系统、沼气利用以及系统运行管理等方面对污泥厌氧消化系统的运行状况进行了对比分析,探讨了污泥厌氧消化工艺在我国北方大型城市污水处理厂应用中存在的主要问题,并指出了解决方向.     

城市污水处理厂污泥的好氧处理研究

为了实现污泥的稳定化、减量化和无害化,对城市污水处理厂的浓缩污泥和厌氧消化污泥进行了好氧处理试验研究.试验结果表明,污泥好氧处理使污泥中有机物质含量降低,臭味减小.厌氧污泥经好氧消化处理后,一方面使污泥得到稳定化和减量化;另一方面,可以把污泥中的致病菌杀死.污泥经好氧消化后沉降性能有明显提高,絮凝剂的加入使其脱水性能也得到一定的改善.     

Source identification of heavy metals in sewage sludge and the effect of influent characteristics: a case study from China

To advance the reclamation of sewage sludge and evaluate the potential risk during sludge application, wastewater and sludge were sampled from seven secondary wastewater treatment plants seasonally in 2016 and 2017. The influent characteristics and the accumulation of eight toxic heavy metals in sludge were analyzed. According to the results, copper, chromium, nickle and zinc were the main heavy metals constraining reclamation of sewage sludge in Shanghai and they were mainly from domestic wastewater. Influent concentration, treatment process and coexisting elements had significant effects on accumulation of heavy metals in sludge. Lead concentration in sludge from AAC plants was generally higher than that from AAO plants, but for other metals the differences were insignificant or depended on the initial concentrations. Nutrients, suspended solids and coexisting heavy metals had significant effects on heavy metal accumulation in sludge when the initial concentration was controlled.     

电动力修复技术去除城市污泥中的重金属研究

分析了城市污水处理厂污泥中重金属的形态，重点考察了不同形态的Cd、Zn在电动力作用下的去除率。结果表明，污泥经电动力作用5d后，对Cd、Zn的总去除率分别为64．50％、65．02％，其中对易被植物吸收的非稳态（可交换态、碳酸盐结合态和铁锰氧化物结合态）Cd、Zn的去除效果尤为明显，去除率分别高达68．60％、75．73％。可见，应用电动力修复技术去除污泥中的重金属是可行的，修复后的污泥可进行土地利用。     

Significance and behaviour of heavy metals in waste water treatment processes II. Sludge treatment and disposal

The literature concerning the significance and behaviour of heavy metals in sewage sludge treatment and following sludge disposal is reviewed. Particular attention is given to metal form during anaerobic digestion and following sludge disposal to agricultural land and to sea, and the influence of metal form on toxicity. It is evident that anaerobic digestion results in a strong association between sludge particulates and heavy metals due to the formation of inorganic precipitates, organo-metallic interactions and by association with the biomass. Toxic inhibition of anaerobic digestion by metals is concluded to be a direct result of the free metal ion concentration and thus mechanisms designed to reduce metal toxicity are based on artificial modification of heavy metal speciation in the digester.Guidelines and legislation designed to limit the application of sludge to agricultural land and the disposal of sludge to sea are reviewed and discussed. Following the application of sludge to agricultural land significant changes occur in heavy metal speciation, which ultimately determine metal availability to plants and potential contamination of groundwaters. Guidelines for application to land currently take limited account of metal form, although the importance of metal speciation is being recognised. Sludge disposal to sea has received relatively little attention with efforts being directed towards monitoring rather than more fundamental research. However, it is apparent that significant heavy metal solubilisation may occur following sludge discharge to the marine environment.It is concluded that sludge disposal to agricultural land and sea, which are increasingly becoming subject to more stringent international pressures, should take account of the ultimate forms of heavy metals in the receiving environment and that a more unified approach should be adopted in the formulation of standards for all forms of sludge disposal.     

污泥堆肥化对重金属生物可利用性的影响

通过重金属形态分析及在模拟雨水、酸雨淋溶条件下重金属迁移实验和理论分析，研究了堆肥化处理对污泥中重金属生物可利用性的影响。结果表明：堆肥化处理使重金属的不稳定形态含量降低，原污泥在酸雨淋溶下重金属已经迁移到约16厘米深的土柱中，而经过处理后的污泥淋出液中的重金属含量很低，仅有少量污泥中含量较高的元素向土柱深层迁移。迁移量及深度明显低于未处理的原污泥。实验及理论分析均证明了堆肥化处理可以降低污泥中重金属在土壤中的迁移性，使重金属的生物可利用性降低。     

Attenuation of heavy metal toxicity of the activated sludge process by treatment with ferric chloride

Industrial wastes containing heavy metals can interfere with the normal operation of municipal wastewater treatment plants utilizing biological treatment processes. It is well known, however, that activated sludge can become acclimated to toxic levels of heavy metals if the dosages are increased gradually. Although such an acclimation procedure could prevent inhibitory effects of slug loads of toxins, the use of toxic heavy metals for normal plant operation is too perilous for consideration. It is, however, acceptable to utilize a nontoxic metal that may give general tolerance to toxic metals.

Laboratory experiments were conducted to examine the use of ferric chloride acclimation for treatment against heavy metal toxicity of an activated sludge process. The oxygen uptake of acclimated and unacclimated seed was measured by respirometry to determine the inhibitory effects of Ag and Pb.

The toxic effects of Ag and Pb were greatly reduced for acclimated seed. The experimental data area utilized in kinetic rate equations, and families of curves are developed to show the inhibition of Ag and Pb at a range of concentrations when the activated sludge is acclimatized at different concentrations of Fe(III).     

造纸污泥堆肥对葡萄的肥效及其重金属风险评价

通过田间试验,考察了造纸污泥堆肥及其复合肥对葡萄的肥效及重金属污染风险.结果表明,施加造纸污泥堆肥和复合肥可以显著提高葡萄的生物量,改善葡萄果实品质,且果实重金属含量符合国家食品卫生标准,对葡萄园土壤的重金属含量也无明显影响,不存在明显的重金属风险.因此,土地施用污泥堆肥及复合肥是合理处置造纸污泥的重要途径.     

城市水质净化厂污泥的好氧发酵处理和利用

城市水质净化厂的污泥含有丰富的有机物和氮、磷、钾等营养素,但也含有重金属、致病菌和寄生虫卵等有害物质,在利用前必须无害化、稳定化。以上海市中心城区水质净化厂80%含水率的脱水污泥为研究对象,进行好氧发酵试验研究,经过1级、2级发酵,所得到的成品能达到无害化、稳定化的目标,可资源化利用。     

堆肥处理对排水污泥中重金属的钝化作用

讨论了城市排水污泥中重金属的含量和形态分布特征，分析了堆肥处理对污泥中重金属结合形态转化的影响。根据不同学者的研究结果，提出堆肥处理可降低污泥中Zn、Cu、Pb、Mn等重金属的活性，并指出堆肥处理是降低污泥在土地利用中重金属污染风险的途径。     

The change in activated sludge surface properties after heavy metals leaching

The change in colloid-chemical properties of natural sludge sol formed as a result of biological treatment of domestic wastewater in the process of heavy metals leaching induced by metabolizing heterotrophic (acidogenic and alkaligenic) chemotrophic biocoenosis was investigated. It was found that bioleaching of heavy metals involving heterotrophs results in hydrophobization of sludge colloids and reduces its negative charge. Heavy metals leaching also results in destabilization of sludge sol, maximum in biological processes. Exopolysaccharides significantly stabilizing sludge sol have a little effect on its stability after heavy metals have been leached.     

电渗析法去除未脱水污泥中重金属的试验研究

为了降低城镇生活污泥中重金属含量,采用三槽型电解槽研究了反应时间和NaClO预处理对未脱水污泥中重金属Zn、Cu、Cr和Ni去除率的影响。试验结果表明,延长反应时间可以提高未脱水污泥中重金属去除率。电渗析反应时间为14 h时,污泥中Zn、Cu、Cr和Ni的去除效果较好,去除率分别为52. 08%、27. 24%、31. 66%和46. 42%。污泥中重金属的初始非稳定态比例越大,电渗析反应后的去除率越高。NaClO/HNO_3组合预处理的污泥中重金属去除率最高,对Zn、Cu、Cr和Ni的去除率分别达到70. 32%、35. 39%、36. 80%和56. 78%。