论城市污泥农用资源化与可持续发展

根据可持续发展观的基本思想，在对城市污泥的特征、处理现状及其对农业和城市发展的影响进行分析的基础上，认为城市污泥的农用资源化对于城市和农业的可持续发展具有重要意义和紧迫性，也是未来城市污泥处置的根本出路，关键在于控制污泥中毒性污染物的含量，科学合理地施用。     

施用污泥对小白菜生长及其迁转重金属的影响

采用盆栽方式,以厦门市筼筜污水处理厂的污泥作为有机肥种植小白菜,探讨污泥施用对小白菜生长和产量的影响及重金属在小白菜-土壤间的迁移转化和积累情况.结果表明:污泥中氮、磷、钾和有机质含量丰富,重金属含量均低于国家农用污泥中污染物控制标准;适宜的污泥施用量可促进小白菜的生长,污泥用量为5%时,小白菜长势最好,生物量最大;污...     

城市污泥应用于陆地生态系统研究进展

随着城市化进程加快和人口剧增,城市污泥已成为世界许多城市面临的主要环境问题之一,且不合理的管理可引发严重的环境污染.城市污泥含有大量、微量元素和有机质,可能对土壤及其生产力有利,特别对退化土壤能进行有机修复,并改善土壤理化特性,譬如土壤结构和营养含量.目前,污泥作为一种有机肥料已成为普遍措施.但来自工业及生活污水的污泥常含有重金属、病原物及有毒有机物等,潜在的毒性可能对生态系统构成危险,因此必须经过污泥预处理才可安全施用.评述了近年来国内外污泥应用于陆地生态系统4个方面的主要研究进展:(1)污泥处理与处置方法;(2)污泥应用于农田、草地及森林生态系统;(3)污泥对土壤生态系统的影响,包括污泥对土壤理化性质、土壤酶及微生物的影响;(4)污泥应用的环境效应.提出未来我国污泥处置及利用需要重视的研究领域和方向.     

城市污泥处理处置技术及资源化利用研究

城市污泥的产量巨大并且成分复杂,如何对城市污泥处置与利用已成为人们所关注的问题.污泥是有用的生物资源,如能合理利用则不仅能变废为宝,还能增加经济效益,所以,探讨适合我国国情的有效处理处置和利用污泥的技术具有重要的现实意义.本文对城市污泥的特性、国内外处理、处置技术和污泥资源化技术的现状进行了分析,认为对污泥进行资源化利用是符合我国国情的一种经济、有效的途径,污泥的资源化利用尤其是农业利用不但可以节省大量的污泥终端处置费用,更可以为肥力低下的农田增添有机质、提高肥力,促进农业生产发展、实现农业生态环境的良性循环.     

污泥的农林处置与利用

1　污泥处置与农林利用现状污泥处置与利用 ,乃当前环境科学中的重要课题。一些污水处理的专家认为 ,污泥处置是污水处理厂当前迫切要解决的难度最大的问题。污泥的处置主要包括农用、填埋、焚烧、排海等。据1 996年资料报道 ,世界上 1 2个发达国家对污泥的处置方式 (表 1 ) ,45.3%为农用 ,38%为填埋 ,1 0 .5%为焚烧 ,6.0 %为排海。西欧、美国和英国的污泥处置 ,西欧以填埋为主 ,美国和英国以农用为主 ,加拿大以焚烧为主 (占 40 % ) [1 ] 。 1 991年和1 998年 ,美国和欧盟已规定禁止向海洋倾倒污泥[1 1 ] ,并且一些发达国家已经明令禁止焚烧…     

污泥堆肥对黄梁木幼苗生长和元素吸收的影响

污泥含有丰富的有机质和植物所需的营养元素,将污泥堆肥后用作苗木栽培基质逐渐成为新型的污泥生态化处置途径.通过7个月的盆栽试验,研究污泥堆肥不同添加量,即0%(CK)、25%(T₁)、50%(T₂)、75%(T₃)、100%(T₄)对黄粱木幼苗生长及营养元素和重金属吸收的影响,以及栽培后基质中元素变化特征.结果表明: 污泥堆肥添加量对黄梁木生长有显著影响,纯污泥(T₄)中黄梁木苗木不能正常生长,移栽两周后植株全部死亡,而T₁、T₂和T₃处理则显著增加了黄梁木株高、地径和总生物量,其中,T₂处理效果最佳,3个生长指标均显著高于其他处理;T₂、T₃处理显著促进黄梁木对N、P、K以及重金属(Cu、 Zn、Pb、Cd)的吸收,而T₁处理仅对N和Pb吸收有显著促进作用;同一处理条件下,黄梁木对污泥堆肥重金属吸收能力表现为Zn>Cu>Pb>Cd.盆栽试验结束时,污泥混合基质中有机质,以及N、P、K含量较高,但仍残留一定量重金属,不过均低于农用污泥污染物控制标准,具有再次利用的价值.     

中国城市污泥土地利用关注的典型有机污染物

污泥土地利用是国内外城市污泥主要的处置方式之一,而污泥中的有机污染物是污泥土地利用的限制性因素之一.本文分析了国内外城市污泥中有机污染物的浓度和研究现状,针对我国国情,认为多环芳烃(PAHs)是城市污泥中一种常见的有机污染物,总含量一般在1 ～ 10 mg·kg-1,有的因污水来源复杂而超过了100 mg·kg-1;壬基苯酚(NP/NPE)在我国污水处理厂污泥样品中均有检出,浓度在1～128 mg·kg-1.污泥园林绿化、林地利用、土壤改良等将是今后主要的利用方向,要实现污泥安全、环保的土地利用,多环芳烃(PAHs)和壬基苯酚(NP/NPE)将是主要考虑的典型有机污染物.     

施污土壤重金属有效态分布及生物有效性

以城市污泥为研究对象,将城市污泥与土壤按照一定的质量比配成污泥混合土壤.采用6种不同性质提取剂(0.05mol/L EDTA、0.1 mol/L CH3 COOH、0.01 mol/L CaC12、1 mol/L CH3COONH4,0.05 mol/L NaHCO3和0.05 mol/L Tris-HCl)分别对污泥混合土壤中重金属(Cd、Pb、Cu和Zn)的螯合态、酸溶态、中性交换态、中性结合态、碱性交换态和蛋白质结合态进行提取,考察污泥的添加对土壤中不同形态重金属的消长规律.通过黑麦草盆栽试验,探究污泥混合土壤中不同形态重金属的植物可利用性.结果表明:污泥混合土壤中重金属螯合态比例较大,占总量的20.3％-40.0％;其次为酸溶态和中性结合态,而中性交换态、碱性交换态和蛋白质结合态的含量较低.污泥的添加促进了黑麦草对Cd、Cu和Zn的吸收,在污泥添加率为44.4％时根部对其吸收量达最大,分别较CK处理增加了0.3、2.3和6.5倍.抑制了对Pb的吸收,在污泥添加率为37.5％时,根部对Pb的吸收较CK处理下降0.4倍.Pearson相关系数分析结果表明:污泥混合土壤中以螯合态、酸溶态和中性结合态存在重金属可被黑麦草吸收利用.     

中国城市污泥有机质及养分含量与土地利用

土地利用是城市污泥的重要处理处置方法,其有机质和养分含量是土地利用中很受关注的问题。关于中国的城市污泥虽然已有不少研究报道,但不同研究结果之间结论并不一致,且缺乏系统的总结。通过系统搜集了20世纪80年代以来全国城市污泥相关的文献资料,重点评述中国城市污泥的有机质含量及其土地利用问题。通过29个城市污泥组成的统计分析发现,中国城市污泥(不包括工业污泥)的有机质平均含量达到384g／kg,全氮、全磷和全钾分别为27、14．3和7g／kg;有机质、全氮、全磷比纯猪粪分别高出1／3～2／3,但全钾比纯猪粪低1／3。中国城市污泥的有机质含量呈逐年增加的趋势,但氮、磷含量变化规律不明显。研究证明,城市污泥在粮食作物、蔬菜、经济作物及园林绿地上使用,具有明显的肥效和改良土壤的效果。近年来,城市污泥中重金属含量越来越低,这有利用促进城市污泥的土地利用,但中国在有机污染物和病原体的危害方面研究相对较少,对城市污泥土地利用的潜在风险仍缺乏长期的定位试验研究。     

城市污泥的特性研究与再利用前景分析

城市污泥的再利用是普遍认可的一种污泥处理途径 ,针对上海 3种典型城市污泥 ,即曲阳生活污泥、金山石化污泥和桃浦化工污泥的特性进行了分析。结果表明 ,3种污泥中Zn和Cd的浓度都超过了相关标准 ,重金属的含量和污泥的类型有关 ,形态分布显著不同 ;曲阳生活污泥中不同气候条件下的大肠菌值≥ 12 0 0MPNs·g-1DM ,而且还有许多其它传染性病原体 ;关于优先控制有机污染物 ,金山石化污泥检出 6种 ,桃浦化工污泥检出 8种 ,而曲阳生活污泥中没有检出。本文还讨论了我国和欧美关于污泥农用的相关控制标准 ,并在此基础上进一步阐述了我国城市污泥再利用的前景和待解决的关键问题     

城市污泥土地利用研究

通过培养试验、盆栽试验和田间试验系统地研究了污泥的组分特征、性质及其农地和城市园林绿化地利用对作物或绿化灌木、土壤肥力及其环境的影响,结果表明,污泥富含有机质和氮磷养分,且养分当季有效性介于化肥农家肥之间。施用污泥将明显提高土壤肥力,表现改善土壤物理性质;增加土壤肥机质和氮磷水平,并增加土壤生物活性,因此施用污泥的处理作物产量较高,并有利于后茬作物的稳健生长。但污泥施用也存在重金属、病原物等污染     

Distribution of heavy metals in a sewage oxidation pond and their adsorption in residual solid (sewage sludge ash)

Abstract

Electrometric studies were carried out on the interaction of heavy metal ions such as manganese, chromium, nickel, copper, zinc, cadmium and lead with the extracted organic matter, humic and fulvic acid from the sludge in a sewage oxidation pond. The distribution of heavy metals was between 60 and 97%, which is associated with the solid waste (sludge) of the oxidation pond. The adsorption/removal efficiency of metal ions onto the sludge ash was more than 90% and 97%, respectively, in the pure system. To obtain the ash, the sludge was burnt at 500°C, treated with nitric acid (1+1) to leach out all the metals and then filtered; the residue left on the filter paper was the pure ash. Both this and that coated with organic matter were studied. The adsorption isotherm for metals, humic/fulvic acids and metal-humic/fulvic acid complexes in the metal-free sludge ash and in the organic matter in the pure system were studied using the Freundlich relationship. Good agreement was found suggesting that sediment and humic/fulvic acids have an important role in the mobility, dispersion and sedimentation of metal ions in an aquatic environment. More of these heavy metals are removed in the pure system than in the natural system. This may be due to the lesser availability of humic and fulvic acids in the lagoons during the short detention time of sewage in suspension in the oxidation pond, whereas the sludge which has settled to the bottom of the pond for several years contains rich decomposed organic matter in the form of humic and fulvic acids containing heavy metals. Such pure systems could be useful for the effective removal of heavy metals.     

Effects of Municipal Sewage Sludge Doses on the Chlorophyll Contents and Heavy Metal Concentration of Sugar Beet (Beta vulgaris var. saccharifera)

The present study was conducted to assess the suitability of sewage sludge amendment (SSA) in soil for Beta vulgaris var. saccharifera (sugar beet) by evaluating the heavy metal accumulation and physiological responses of plants grown at a 10%, 25%, and 50% sewage sludge amendment rate. The sewage sludge amendment was modified by the physicochemical properties of soil, thus increasing the availability of heavy metals in the soil and consequently increasing accumulation in plant parts. Cd, Pb, Ni, and Cu concentrations in roots were significantly higher in plants grown at 25% as compared to 50% SSA; however, Cr and Zn concentration was higher at 50% than 25% SSA. The concentrations of heavy metal showed a trend of Zn > Ni > Cu > Cr > Pb > Cd in roots and Zn > Cu > Ni > Cr > Pb > Cd in leaves. The only instance in which the chlorophyll content did not increase after the sewage sludge treatments was 50%. There were approximately 1.12-fold differences between the control and 50% sewage sludge application for chlorophyll content. The sewage sludge amendment led to a significant increase in Pb, Cr, Cd, Cu, Zn, and Ni concentrations of the soil. The heavy metal accumulation in the soil after the treatments did not exceed the limits for the land application of sewage sludge recommended by the US Environmental Protection Agency (US EPA). The increased concentration of heavy metals in the soil due to the sewage sludge amendment led to increases in heavy metal uptake and the leaf and root concentrations of Ni, Zn, Cd, Cu, Cr, Pb, and Zn in plants as compared to those grown on unamended soil. More accumulation occurred in roots and leaves than in shoots for most of the heavy metals. The concentrations of Cd, Cr, and Pb were more than the permissible limits of national standards in the edible portion of sugar beet grown on different sewage sludge amendment ratios. The study concludes that the sewage sludge amendment in the soil for growing sugar beet may not be a good option due to risk of contamination of Cr, Pb, and Cd.     

构树的污泥适应性及养分和重金属吸收累积特征

构树是我国重要速生经济树种,具有适应性强、生物量大和重金属富集能力强等优点,而污泥中含有大量养分和重金属,在污泥中种植构树有望同时实现污泥生态修复和构树资源生产。本研究通过盆栽试验,分析在对照(赤红壤)、50%污泥(污泥、赤红壤混合基质,重量比各50%)和100%污泥基质中构树生长及不同部位(根、茎、叶)养分和重金属吸收累积特征,并通过主成分分析和隶属度函数对吸收累积能力进行综合评价。结果表明: 构树在50%和100%污泥中均可正常生长且株高、生物量显著高于对照,在100%污泥中长势最好,质量指数(1.02)分别是对照和50%污泥处理的4.3和2.4倍。50%和100%污泥处理构树各部位N含量和茎P含量显著高于对照,100%污泥处理构树茎、叶K含量显著低于对照。构树对Cu、Zn、Pb、Cd、Ni的吸收部位以根为主,根系重金属含量与污泥比例呈正相关,叶Pb、Cd含量符合《饲料卫生标准》(GB 13078—2017)。构树对Cd的吸收累积效果好于其他重金属元素。与对照相比,50%和100%污泥处理构树根部Zn、Pb、Cd滞留率显著提高(57.8%~85.8%),100%污泥处理构树根部Cu、Ni滞留率显著提高(67.5%和74.8%)。污泥处理全株养分和重金属累积量均显著大于对照,其中100%污泥处理显著大于50%污泥处理。与50%污泥处理相比,100%污泥处理构树各部位及全株养分和重金属累积量大幅提高。不同处理下构树污泥适应性和元素吸收累积的综合评价得分为100%污泥(0.848)>50%污泥(0.344)>对照(0.080)。构树对污泥具有良好的适应性,在纯污泥中能够正常生长并具有较强的吸收累积养分和重金属能力,可在修复污泥的同时进行构树资源生产。     

Mid‐term effects on ecosystem services of quarry restoration with Technosols under Mediterranean conditions: 10‐year impacts on soil organic carbon and vegetation development

The use of Technosols for the restoration of limestone quarries overcomes the usual “in situ” scarcity of soil and/or its poor quality. The use of mine spoils, improved with mineral and/or organic amendments, could be an efficient and environmentally friendly option. Properly treated sewage sludge from urban wastewater treatment plants could be a suitable organic amendment and fertilizer (rich in N and P) whenever its pollutant burden is low (heavy metals and/or organic pollutants). Its appropriate use could improve essential soil physical and chemical properties and, therefore, promote key ecosystem services of restored areas, such as biomass production and carbon sequestration, as well as biodiversity and landscape recovery. However, the mid‐term impacts of these restoration practices on soil functioning and their services have rarely been reported in the available literature. In this study we assess the mid‐term effects (10 years) of the use of sewage sludge as a Technosol amendment on soil organic carbon (SOC), nutrient status, and plant development in several restored quarries. Soils restored using sewage sludge showed a threefold increase in SOC compared to the corresponding unamended ones, despite the moderate sludge dosage applied (below 50 tonnes/ha). Plant cover was also higher in amended soils, and recruitment was not affected by sludge amendment at these doses. This study demonstrates that, used at an appropriate rate, sewage sludge is a good alternative for the valorization of mine spoils in quarry restoration, improving some important regulatory ecosystem services such as carbon sequestration, without compromising woody plant encroachment.     

Terrestrial Chironomidae on agricultural soil treated with sewage sludge

Adult Chironomidae were caught in emergence traps for three subsequent years (1988–1990) on agricultural soil. Larvae were extracted from soil samples taken since June 1989. The field was subdivided into 5 plots treated with different amounts of sewage sludge. On some plots the sludge was artificially enriched with heavy metalts. The phenology of Chrinonomidae in the three years and their distribution over the different plots are discussed. The results suggest that the abundance of Chironomidae is increased by sewage sludge and appears to be also increased by heavy metals.     

Mobility and Distribution of Zinc,Cadmium and Lead in Calcareous Soils Receiving Spiked Sewage Sludge

Leaching column experiments were conducted to determine the degree of mobility and the distribution of zinc (Zn), cadmium (Cd), and lead (Pb) because of an application of spiked sewage sludge in calcareous soils. A total of 20 leaching columns were set up for four calcareous soils. Each column was leached with one of these inflows: sewage sludge (only for two soils), spiked sewage sludge, or artificial well water (control). The columns were irrigated with spiked sewage sludge containing 8.5 mg Zn l^?1, 8.5 mg Cd l^?1, and 170 mg Pb l^?1 and then allowed to equilibrate for 30 days. At the end of leaching experiments, soil samples from each column were divided into 18 layers, each being 1 cm down to 6 cm and 2 cm below that, and analyzed for total and extractable Zn, Cd and Pb. The fractionation of the heavy metals in the top three layers of the surface soil samples was investigated by the sequential extraction method. Spiked sewage sludge had little effect on metal mobility. In all soils, the surface soil layers (0-1 cm) of the columns receiving spiked sewage sludge had significantly higher concentrations of total Zn, Cd and Pb than control soils. Concentration of the heavy metals declined significantly with depth. The mobility of Zn was usually greater than Cd and Pb. The proportion of exchangeable heavy metals in soils receiving spiked sewage sludge was significantly higher than that found in the control columns. Sequential extraction results showed that in native soils the major proportion of Zn and Pb was associated with residual (RES) and organic matter (OM) fractions and major proportion of Cd was associated with carbonate (CARB) fraction, whereas after leaching with spiked sewage sludge, the major proportion of Zn and Pb was associated with Fe-oxcide (FEO), RES, and CARB fractions and major proportion of Cd was associated with CARB, RES and exchangeable (EXCH) fractions. Based on relative percent, Cd in the EXCH fraction was higher than Zn and Pb in soils leached with spiked sewage sludge.     

几种花卉植物对污泥中铅的富集特征

土地利用是资源化利用城市污水厂污泥的有效途径。为了解污泥中重金属污染物在土壤、植物之间的迁移富集规律,选用8种园林用植物进行污泥混配土种植实验。结果表明,植物对污泥混配土土壤中铅的富集能力,以及铅在植物中各器官的富集系数均不同,且不同种类植物差别较大。植物根部对铅有较强的富集能力,其次是叶和茎。菊花对铅的富集能力较强。植物对土壤中铅的富集能力也受土壤铅含量和赋存形态影响。     

城市污泥在矿山废弃地复垦的应用探讨

Based on the analysis of the existing problems in reclaimingabandoned mining land and their negative effect on the ecological environment,and in view of the limited factors to reclaim abandoned mining land,this paper puts forward the suggestions of using sewage sludge as an alternative in mining land reclamation.Application of sewage sludge in reclamation has beneficial effects, such as increasing organic matter content, preventing soil erosion,recovering vegetation,and promoting microbial population and its activities.Unfavorable factors including heavy metal and organic pollutant for applications of sewage sludge and their countermeasures are also discussed.