剩余污泥厌氧消化过程重金属形态转化及生物有效性分析

为研究污泥厌氧消化过程中物理化学性质的变化对典型重金属形态转化的影响,对其农用的可行性及生物有效性进行评估,对取自某城市污水处理厂的剩余污泥进行了序批式厌氧消化实验,在试验过程中测定了污泥理化学性质,采用Tessier分步提取法提取了污泥样品中的典型重金属,并采用电感耦合等离子发射光谱仪（ICP-OES）测定各形态重金属含量及总量。结果表明,厌氧消化过程中重金属的形态发生了显著变化,由不稳定态向比较稳定的残渣态和有机结合态转变,某些重金属形态与污泥理化性质如pH、碱度、VS/TS及氨氮显著相关。厌氧消化可以有效地降低污泥中重金属的潜在迁移能力和生物有效性,经厌氧消化后污泥可以更好地进行土地利用。     

农村生活垃圾半连续式厌氧消化产沼气性能及H2S含量控制

为探究农村生活垃圾厌氧消化过程及对H_2S产量的抑制,采用半连续完全混合式反应器,对农村生活垃圾进行半连续式厌氧消化试验,分析在不同有机负荷下厌氧消化系统中有机质的降解性能、产气性能及稳定性,确定生活垃圾厌氧消化最佳有机负荷。同时设计生活垃圾与浓缩污泥不同配比的序批式厌氧消化试验,观察沼气中H_2S含量的变化。研究结果表明:有机负荷为4 g/(L·d)时,产甲烷率上升最为显著,系统稳定运行且生活垃圾的有机质利用率较高;随着浓缩污泥添加量的增加,H_2S含量降低明显,当生活垃圾与浓缩污泥的VS质量比(VSRSW∶VSCS)为1∶0.25,1∶0.5,1∶0.75时,H_2S的降解率分别达到85.15%,88.18%,96.20%。生活垃圾与浓缩污泥的成分分析得出2种物料的金属含量并无明显差异,但浓缩污泥中的腐殖质含量远远高于生活垃圾,进而判断污泥中的腐殖质含量一定程度的影响厌氧消化系统中H_2S的产量。     

污水污泥的厌氧消化研究

本文对世界各国有关城市污水污泥的厌氧消化方法作一综述，着重介绍了中温厌氧消化，高温厌氧消化和其他新型高效的厌氧消化方法。     

污泥厌氧消化过程的流变规律与脱水性能

为阐明厌氧消化过程中污泥流变学与污泥理化性能(脱水性能)之间的关联及低温水解预处理对污泥厌氧消化产气的影响,对常规污泥及低温热水解预处理污泥进行厌氧消化试验,结果表明试验结束时,低温热水解-厌氧消化的挥发性固体(volatile solids, VS)去除水平较常规厌氧消化污泥提高3.7个百分点,低温热水解预处理也使得消化污泥的脱水性提高1.59%;污泥屈服应力分别了降低了64.51%和71.47%;稠度系数分别减小了90.94%和92.83%,污泥流动性增强。整个消化过程VS/总固体(totalsolids,TS)和屈服应力随时间的变化均呈对数下降趋势;通过线性方程拟合和皮尔逊相关性分析表明,屈服应力与VS/TS、屈服应力变化与脱水性能改善两两间的拟合优度(R^2)均大于0.94,表明在厌氧消化过程中屈服应力、屈服应力变化与污泥VS/TS、脱水性能具有较好的线性关系。研究结果从流变学角度为厌氧消化过程中的监控和优化提供新思路和理论依据。     

花生壳磁性生物炭对颜料污泥厌氧消化及重金属形态的影响

投加外源添加剂磁性生物炭（Magnetic Biochar,MBC）是解决颜料污泥厌氧消化效率低和重金属钝化效率低的有效途径。该研究选取农业废弃物花生壳制备生物炭（Biochar,BC）,而BC对厌氧消化和重金属钝化的影响有限,对其赋磁改性制得MBC以提升影响效果。设置3组厌氧消化批式试验,A组为对照组,B组投加BC,C组投加MBC,探索花生壳MBC对颜料污泥厌氧消化效率及重金属Cr和Ni钝化的影响。结果表明,MBC投加可有效提升消化系统挥发性脂肪酸（Volatile Fatty Acids,VFAs）的产量,最高VFAs浓度达914.5 mg/L,较对照组（最高浓度603.9 mg/L）提升51.4%。同时MBC可实现生物炭和Fe3O4的双重直接种间电子传递（Direct Interspecies Electron Transfer,DIET）效应的耦合,缓解消化系统的酸化并提高有机物去除率和CH4累积产量。与对照组相比,挥发性固体（Volatile Solid,VS）去除率、累积甲烷产量、平均日甲烷产量和平均日甲烷产率分别提升37.8%、56.3%、56.3%和37.2%。此外,MBC投加可有效降低颜料污泥的重金属生物可利用态分配率和提升钝化效率,与原料相比,Cr的可交换态、可还原态质量占比降低43.6%、61.6%,而可氧化态、残渣态质量占比提升53.2%、243.6%;Ni的可交换态、可还原态质量占比降低41.0%、59.2%,而可氧化态、残渣态质量占比提升65.2%、181.4%。研究结果表明MBC可有效提高颜料污泥厌氧消化效率并降低重金属Cr和Ni的生物利用度,该研究有助于实现颜料污泥的稳定化、无害化、资源化利用。     

餐厨垃圾高温厌氧消化接种物的驯化研究

研究不同投料方式对餐厨垃圾高温厌氧消化接种物产气活性的影响，探求餐厨垃圾高温厌氧消化接种物的最佳驯化方法。在55℃条件下，采用不同方式对厌氧污泥进行驯化作为餐厨垃圾高温厌氧消化的接种物，观察了驯化前后污泥中微生物菌群的形态结构，考察了驯化过程中污泥pH值和VFA(挥发性脂肪酸)浓度的变化，并且比较了驯化后污泥的产气活性，结果表明：污泥经过添加一定量的餐厨垃圾驯化培养后，其微生物菌群形态由球形演变为单一的杆状菌体，且分布较分散，产气活性也有所提高，其中每日投加餐厨垃圾2.5 g(污泥质量的0.5％)，驯化2     

投加粉煤灰污泥好氧消化对重金属稳定化研究

通过投加粉煤灰污泥好氧消化,来改变污泥中重金属的形态,使其稳定,以减弱对环境的危害。对污泥好氧消化前后重金属Cu、Ni、C(r总铬)、Mn、Zn等5种重金属化学形态的分析,结果表明:Cu、Ni、Cr3种重金属有机结合态及硫化物所占比重有所增加,Mn、Zn2种重金属不稳定态所占比重有所增加。污泥投加粉煤灰好氧消化可以稳定污泥中部分的重金属。     

连续污泥农用对土壤微团聚体及有机质组分中 重金属分布的影响

采用物理和化学相结合的分组方法,将土壤逐级分离成不同粒径后再分出以有机无机复合体存在的重组,研究施加不同污泥后土壤中不同粒径颗粒、不同重组结合态腐殖质组分中Cu、Zn、Cd的分配特征。结果表明:土壤重金属浓度随其粒径减小呈不断升高趋势,但施用污泥增加了土壤细砂粒级组分中的重金属比例,且随施用污泥中重金属浓度上升而增加。施加污泥后,不同粒径土壤颗粒中松结态腐殖质比例明显增加,紧结态腐殖质所占比例下降。施加污泥后土壤细砂颗粒松结态腐殖质中Cu、Zn、Cd所占比例上升,紧结态腐殖质中Cu、Zn、Cd比例下降。粉砂粒级松结态腐殖质中Cu、Cd比例上升,紧结态腐殖质中Cu、Cd比例下降。细粉砂和胶体粒级不同结合态腐殖质中Cu、Zn、Cd比例没有明显变化。不同粒径组分土壤颗粒中重金属比例变化不仅与不同结合态腐殖质的比例有关,还与土壤颗粒大小和土壤性质有关。     

葡萄酒生产废弃物与剩余污泥厌氧共消化研究进展

厌氧消化技术被广泛应用于多种行业废弃物的处置。然而,葡萄酒生产废弃物浓度高、pH值低以及季节性变化的特性容易造成负荷冲击,导致反应器微生物流失、运行不稳定。同时,剩余污泥组分复杂、水解率低导致产气效率低。厌氧共消化具有均衡营养素、减缓抑制效应、丰富菌群多样性和提高甲烷产量等优势,也逐渐成为一种重要的葡萄酒生产废弃物与剩余污泥的处置方式。尽管已有二者在不同运行策略下共消化性能的研究,但仍未有报道阐明其共消化的影响因素以及基于葡萄酒生产废弃物特性建立直接种间电子传递的研究进展。因此,该文介绍了葡萄酒生产废水与剩余污泥、葡萄酒生产固体废弃物与剩余污泥的共消化进展,并分别归纳了2种体系中影响消化效能的主要因子;随后总结了共消化体系中基于乙醇建立的直接种间电子传递的研究进展;最后,围绕以上内容展望了共消化技术在葡萄酒生产废弃物与剩余污泥协同处理的前景。     

连续污泥农用对土壤微团聚体及有机质组分中 重金属分布的影响

采用物理和化学相结合的分组方法,将土壤逐级分离成不同粒径后再分出以有机无机复合体存在的重组,研究施加不同污泥后土壤中不同粒径颗粒、不同重组结合态腐殖质组分中铜锌镉的分配特征。结果表明,土壤重金属浓度随其粒径减小呈不断升高趋势,但施用污泥增加了土壤细砂粒级组分中的重金属所占比例,且随施用污泥中重金属浓度上升而增率升高。施加污泥后,不同粒径土壤颗粒中松结态腐殖质比例明显增加,紧结态腐殖质所占比例下降。施加污泥后土壤细砂颗粒松结态腐殖质中铜锌镉所占比例上升,紧结态腐殖质中铜锌镉所占比例下降。粉砂粒级松结态腐殖质中铜镉比例上升,紧结态腐殖质中铜镉所占比例下降。细粉砂和胶体粒级不同结合态腐殖质中铜锌镉比例没有明显变化。不同粒径组分土壤颗粒中重金属比例变化不仅与不同结合态腐殖质的比例有关,还与土壤颗粒大小和土壤性质有关。     

污泥农用对土壤和作物重金属累积及作物产量的影响

以3 a定位试验为基础,比较3种不同处理的污泥肥料（消化污泥、污泥堆肥及污泥复混肥）农田施用下土壤养分、土壤和作物籽粒中Mn、Cu、Zn、Pb、Cd 5种重金属的积累以及作物产量的变化情况,以阐明污泥农用对土壤及作物的影响。研究表明,3种污泥肥料提高了土壤中氮素和有机质的含量;与空白和普通化肥处理相比,3种污泥肥料增加了土壤中Mn和Cu的含量,而对土壤交换态重金属含量没有显著影响;3种污泥处理均增加了小麦籽粒中Zn的含量;相对普通化肥处理,3种污泥肥料处理对小麦和玉米产量均无显著影响。合理施用污泥肥料可以有效地提高作物产量;污泥肥料施用对土壤重金属有一定累积效应,但短期施用对土壤比较安全。     

Effects of sewage sludge stabilization on organic‐N mineralization in two soils

Sewage sludge is a valuable source of organic matter, N, P and certain micronutrients that have beneficial effects on plant growth and biomass production. However, sanitary regulations often require the stabilization of sewage materials prior to applying them to soils as biosolids. Environmental regulations also demand appropriate management of biosolid‐N to avoid groundwater contamination. Because stabilization processes usually make sewage sludge less putrescible, we hypothesized that the mineralization rates of organic‐N from stabilized biosolids would be affected. Therefore, this study aimed to evaluate the mineralization of five biosolids in two soils – a sandy Spodosol and a clayey Oxisol. Digested sludge, composted sludge, limed sludge, heat‐dried sludge and solar‐irradiated sludge were mixed with soil samples at a concentration of 32.6 mg N/kg soil (1.0 dry t/ha of digested sludge) and incubated at 25 °C in a humidity chamber for 23 weeks. Results showed that the stabilization processes generally slowed the release of mineral‐N in soils relative to the digested sludge from which the biosolids originated. However, increments in the levels of mineral‐N were more influenced by soil type than by the type of stabilization process applied to the sewage sludge. Mineralization rates were up to 5‐fold higher in the Oxisol than in the Spodosol soil, and as a result, organic‐N in biosolids mineralized 10–24% in Spodosol and 23–52% in Oxisol. Any appropriate plan for the management of biosolid‐N for plant use should consider the interaction between soil type and biosolid type.     

污泥污水在棉花上的施用: Ⅰ.对土壤性质的影响

A field experiment with cotton was conducted on a well drained,calcareous,clay loamy Typic Xerochreph to investigate the utility of sewage sludge as a partial substitute for fertilizers and the influence of tis application on the basic soil properties and heavy metal concentrations.The experimental design was completely randomized blocks with five treatments replicated four times each.Sewage sludge came from the treatment plant of the municipality of Volos,Central Greece,with the following characteristics:organic matter content 36.6%,pH(H2O1:5)6.89,CaCO3 53.4g kg^-1,total N 265.g kg^-1,ttal P33.5g kg^-1,and total K 968mg kg^-1 soil.Heavy metal concentrations were Cd 5.24,Pb 442,Ni38,Cu 224,Zn1812,and Mn 260mgkg^-1 dry weight,respectively.The soil was high in potassium(K)and poor in available phosphorus(P).The results showed that sewage sludge application increased cotton yield and K and P concentrations in cotton leaves,Soil pH was reduced in the case of higher sewage sludge rate.Electrical conductivity,organic matter content,totalN,and avaiable P were significantly increased.Total concentrations of Zn,Pb,and Cu were slightly increased.DTPA-extractable Zn,Cu,and Mn were also significantly increased.Available forms of all heavy metals,except Cd,were significantly correlated with organic matter content in a positive way and negatively with soil pH.     

Elemental Relationships and Growth and Development of Spinach Grown with Sewage Sludge

A pot experiment with spinach (Spinacia oleraceae L. Fam.: Chenopodiaceae) was conducted aiming to investigate the effect of the addition of sewage sludge (SS) on soil substrate, the growth of spinach, and the plant interactions of CaxCd and ZnxCd. There were six substrates obtained by mixing soil and sludge in different proportions by volume (20:1, 10:1, 6.7:1, 5.0:1, 4.0:1, 3.3:1) and a control (only soil). The highest biomass was achieved in treatments 20:1 and 10:1. There was not a linear increase due to toxicity when SS was added in higher proportions. Sludge improved soil fertility by increasing organic matter and total N. Furthermore, in all plant parts of spinach, the Ca and Zn contents were synergistically interrelated with the Cd content, facilitating Cd uptake. The use of sewage sludge as soil amendment is not applicable on agricultural land due to the accumulation of Cd in plant.     

污泥中重金属的环境活性及生态风险评估

研究了湖南省长沙市、株洲市和常德市10个污水处理厂剩余污泥中As,Cd,Cu,Ni,Pb,Zn的含量和形态特征,并利用潜在生态危害指数法对污泥农用过程中重金属的生态风险进行了综合评价。结果表明,城市污泥中富含有机质及N,P,K等养分,然而,污泥表现为以Cd为主的多金属污染,不能直接农用。污泥中Cd含量为1.43～260mg/kg,以可还原态为主,占全量比例高于28.9%;As,Pb的可还原态,Ni,Zn的酸可溶态和可还原态,Cu可还原态和氧化态所占比例较高,表明污泥中重金属的潜在环境活性较高。风险指数评价结果表明,污泥中Cd和As是潜在的强生态风险元素;以工业废水处理为主的污水处理厂污泥重金属单因子生态风险相对较高,且综合潜在生态风险严重。     

Die Wirkung von ausgefaultem Klärschlamm auf den Stoffwechsel 3jähriger Fichten und Kiefern

Effect of digested sewage sludge on the metabolism of three year old spruce and pine trees. Three year old Norway spruce and Scots pine trees were grown in mixtures of sand and sewage sludge. The mixtures used were composed of 5 litres of sand and 1.25 or 1.67 litres of digested sewage sludges from municipal waste water treatment plants. A mixture of 5 litres of sand and 1.67 litres of peat was used as a control. In all cases sewage sludge depressed growth as measured by height and the yields of fresh material. The contents of N, Ca, Mg, Zn in the needle dry matter were higher than in control. The P content was only increased in the newly formed needles in the high sewage sludge treatments. However, the corresponding Mn contents were depressed, also the K contents in spruce. The higher rate of nitrogen assimilation, in the sewage sludge treatments especially in spruce, lead to a greater accumulation of the amino acid arginine and also to a reduction in the content of organic acids and polyphenols. These effects do not explain why some plants died. For spruce a lethal factor appears to be the depression of water uptake combined with high transpiration. The ratio of K/Ca in the needles was extremly low, which indicated a possibility of both potassium deficiency and calcium toxicity. The observed enrichment of proline is also associated with water stress. Scot pine was more sensitive than spruce to treatment with sewage sludge. In all treatments with sludge some Scot pine trees died, especially when municipal wastewater sewage sludge was used.     

贵州省典型城市污水处理厂污泥养分与重金属含量调查

分别采集贵州省8个典型地级城市污水处理厂冬季和夏季的脱水污泥样品,进行室内分析测试,研究其养分和重金属特性。结果表明,贵州省主要地级城市脱水污泥pH为6.5-7.4,盐分含量为0.4-0.9。城市污泥中有机质、全量N、P高于一般农家肥,但全K量较低。污泥中全量重金属Cu、Pb、Ni、Cr、Hg和As均远低于国家农用标准,但一个处理厂污泥Cd、Zn超标,另有一处理厂污泥Cd超标,有3个处理厂污泥存在Zn超标现象。形态分析表明,Cd在多数污泥中化学形态主要是以生物有效态的形式存在,而Zn主要以稳定的化学形态存在,说明Cd存在环境风险,而Zn相对安全,表明贵州地区脱水污泥多数可安全农用,冬季和夏季脱水污泥的养分和重金属浓度没有显著差异。     

Dynamics of Organic C Mineralization and the Mobile Fraction of Heavy Metals in a Calcareous Soil Incubated with Organic Wastes

Organic wastes such as sewage sludge and compost increase the input of carbon and nutrients to the soil. However, sewage sludge-applied heavy metals, and organic pollutants adversely affect soil biochemical properties. Therefore, an incubation experiment lasting 90 days was carried out to evaluate the effect of the addition of two sources of organic C: sewage sludge or composted turf and plant residues to a calcareous soil at three rates (15, 45, and 90 t of dry matter ha^–1) on pH, EC, dissolved organic C, humic substances C, organic matter mineralization, microbial biomass C, and metabolic quotient. The mobile fraction of heavy metals (Zn, Cd, Cu, Ni, and Pb) extracted by NH₄NO₃ was also investigated.The addition of sewage sludge decreased soil pH and increased soil salinity to a greater extent than the addition of compost. Both sewage sludge and compost increased significantly the values of the cumulative C mineralized, dissolved organic C, humic and fulvic acid C, microbial biomass C, and metabolic quotient (qCO₂), especially with increasing application rate. Compared to compost, the addition of sewage sludge caused higher increases in the values of these parameters. The values of dissolved organic C, fulvic acid C, microbial biomass C, metabolic quotient, and C/N ratio tended to decrease with time. The soil treated with sewage sludge showed a significant increase in the mobile fractions of Zn, Cd, Cu, and Ni and a significant decrease in the mobile fraction of Pb compared to control. The high application rate of compost resulted in the lowest mobility of Cu, Ni, and Pb. The results suggest that biochemical properties of calcareous soil can be enhanced by both organic wastes. But, the high salinity and extractability of heavy metals, due to the addition of sewage sludge, may limit the application of sewage sludge.     

生活污泥对滩涂土壤性质和苏丹草生长及重金属累积的影响

滩涂盐土农业利用的主要障碍是盐分含量过高和缺乏有机质。施用生活污泥可快速提高滩涂土壤有机质含量,加快土壤熟化,但由于担心污泥含有一定量的重金属,其施用受到一定的限制。采用盆栽苏丹草的试验方法,研究滩涂盐土施用不同量的生活污泥后对土壤性质、植物生长和对重金属累积的影响。结果表明,生活污泥施用于滩涂盐土后降低了土壤pH值,提高了EC值和总盐含量;苏丹草的出苗率、株高和鲜重增加;施用污泥提高了苏丹草植株中全氮、全磷及叶绿素的含量,且随施用量的增加而增大,但对植株中全钾的含量无显著影响;苏丹草中Zn、Cd含量随着污泥施用量增加呈增长的趋势,但Pb、Ni、Cu含量变化不大。在试验条件下,所施用污泥中重金属向苏丹草体内转移的比例介于0.13%-13.44%之间。就该种土壤而言,要更为注意含Pb量较高的污泥施用,而Cu则是最为安全的。总体考虑,一次性施用干污泥应控制在8t·667m^-2以下。     

蚯蚓活动对城市生活污泥重金属的影响

采用塑料温棚内垄式堆积污泥培养蚯蚓方式,研究了蚯蚓处理对污泥重金属的影响。结果表明,污泥经蚯蚓处理后,理化性质发生了显著的变化,污泥的pH值、有机质、总氮和总磷都有不同程度的降低;蚯蚓能吸收富集污泥中的重金属,其中对重金属Cd有较强的富集能力;蚯蚓处理使污泥中重金属含量均出现不同程度的下降,重金属Cr、Zn、Pb、Cd、Cu、Ni分别减少27.98%、31.46%、32.81%、13.85%、23.86%和22.92%。利用盆栽试验,研究了污泥施用于土壤后生菜体内重金属积累的情况,结果表明,生菜体内重金属Zn、Cu、Pb和Ni的含量为污泥处理高于蚓粪处理;Cr和Cd则分别为差异不显著和略有降低。