郑州市污水污泥特性及其堆肥的可行性分析

为了对郑州市城市污水污泥的有效资源化利用途径进行合理建议,对郑州市现有的3座城市污水处理厂的污泥进行了取样分析.结果表明,经过消化处理的污泥偏碱性,未经消化的污泥偏酸性,样品水分含量较高(78%～83%),含有丰富的有机质、全氮、全磷和全钾,重金属含量相对较低,均符合国家<农用污泥中污染物控制标准>;现有土地填埋法对环境存在很大隐患,也浪费了大量营养,对其营养成分和有害成分进行分析,表明对其进行堆肥处理是可行的.     

昆明城市污泥性质及土地利用方式探讨

分析昆明市6个生活污水处理厂污泥的特性.昆明城市污泥含水率、有机质、总氮、总磷含量很高,总钾含量偏低,重金属Cu、Zn、Pb、Cd、As、Hg的含量满足<城镇污水处理厂污泥处置农用泥质>(CJ/T309-2009)、<城镇污水处理厂污泥处置园林绿化>(GB/T23486-2009)以及<城镇污水处理厂污泥处置土地改良>(CJ/T291-2008)要求,昆明城市污泥可以用于园林绿化、矿山废弃地以及农用.     

市政污泥中重金属赋存状态及生物有效性

在分析污泥理化性质的基础上,采用Tessier连续提取法对污泥中的Cu、Zn、Pb、Ni、Cd、Cr进行形态及生物有效性分析.结果表明,该污泥中有机质含量达到45.62 %,N、P、K含量分别为1.55 %、4.26 %、1.01 %,重金属含量均低于污泥农用控制标准值.污泥中Cu的生物有效态占2.65 %,潜在有效态占36.52 %,不可利用态占60.83 %;Zn的生物有效态占1.24 %,潜在有效态占10.71 %,不可利用态占88.05 %;Pb全部以残渣态存在于污泥中,不可利用态占100 %;Ni的生物有效态占46.01 %,不可利用态占53.99 %;该污泥中未检测出Cd和Cr.污泥中重金属主要以非交换态形式存在,生物可利用程度低,对污泥堆肥农用非常有利.      

含铬电镀污泥资源化利用技术研究进展

混合电镀污泥中含有铬、铜、镍、锌等重金属和贵金属。介绍了含铬电镀污泥高值资源化方法研究进展,涉及酸浸法、氨浸法、微生物提取法、材料化利用等,分析了混合电镀污泥高值资源化利用的主要问题及发展趋势,指出铬的分离提取是电镀污泥高值利用的关键。     

城市污泥堆肥对菠菜生长和土壤环境的影响

[目的]探讨城市污泥堆肥施加于菠菜地的可行性及其施加控制量.[方法]以北京市庞各庄污泥堆肥厂的污泥堆肥作为蔬菜地施用的有机肥源,采用自制土柱试验装置,研究不同用量污泥堆肥施用后菠菜的生长情况及对土壤的影响.试验设4个处理,污泥堆肥施用量分别为0(ck)、2、4、和6 kg/m<'2>[结果]壤土和沙土上不同用量污泥堆肥施用后,菠菜的株高、冠幅和叶面积都有一定的增加,对菠菜生长有促进作用,以4 kg/m<'2>处理的效果最好.污泥堆肥施用后对菠菜重金属含量有显著影响,明显提高了菠菜地土壤中养分及有机质含量,污泥堆肥用量与污泥中重金属含量之间呈显著相关关系.[结论]城市污泥堆肥可以施加于蔬菜地,施加量以4 kg/m<'2>为宜.     

污泥堆肥应用于废弃金属矿山表土基质改良的研究

利用城镇污水处理厂污泥好氧堆肥产物与废弃矿山表土进行掺混开展盆栽试验，通过对土壤基本理化性质、植物生长情况、土壤酶活性以及微生物含量的分析，研究了城镇污水厂污泥应用于矿山表土改良的可行性。结果显示，在20%的污泥堆肥掺混比例下，与原废弃矿山表土相比，有机质含量提升了4.4倍，土壤全氮含量提升了9.5倍。因此，污泥堆肥可以显著的提升矿山表土的肥力，有效地改善土壤微生物数量与酶的活性，促进植物的生长和生态恢复。     

从电镀污泥中回收有价金属的研究进展

电镀污泥成分复杂,含有铁、铬、镍、铜和锌等多种有价金属,是重要的二次资源。综述了近年来国内外对电镀污泥中有价金属的回收方法及研究进展,分析了各方法的优缺点,认为化学沉淀法具有较好的应用前景。     

转炉污泥生产烧结矿研究

炼钢污泥含铁量高，是很好的二次原料，可以返回冶炼工序进行回收和利用。污泥主要含有粒度小于0．05mm的颗粒，因此在供给冶炼设备之前要求进行压块。     

电镀污泥中有价金属的湿法回收技术

电镀污泥中含有铜、镍、铬、锌等多种有价金属元素,本文以铜和镍的回收为重点,简述了从电镀污泥中回收有价金属的湿法工艺。     

蚯蚓堆肥在污泥处理中的应用

概述了利用蚯蚓处理污泥技术的基本原理、生活污泥和工业污泥蚯蚓堆肥研究的历史和现状,介绍了国内外的应用实例.蚯蚓污泥堆肥技术具有设备简单、操作方便、费用低廉等特点,能处理多种类型的污泥;处理后污泥无害化、稳定化和减量化,可资源化利用;该技术应用前景可观,尤其适合城镇小型污水厂的污泥处理.     

Using the Kinetics of Biological Flocculation and the Limiting Flux Theory for the Preliminary Design of Activated Sludge Systems. I: Model Development

Current activated sludge models consider that the removal of biodegradable organics by suspended growth includes rapid enmeshment of the organic particles in the microbial floc, hydrolysis of the complex organic molecules into readily biodegradable organic substances, and oxidation of dissolved organic substances. All of the models assume hydrolysis is the rate-limiting step, but none consider the role that the kinetics of biological flocculation and the sludge settling characteristics may play in defining the activated sludge operating parameters. Several researchers have studied the kinetic of biological flocculation, and have analyzed its role on the removal of particulate COD in suspended growth reactors. It has been demonstrated that a large proportion of the organic matter present in sewage can be removed by biological flocculation using short hydraulic retention times and subsequent settling. This paper demonstrates that the one-dimensional limiting flux theory may be useful for coupling the sludge settling properties with the aeration tank behavior, and is a reasonable first approximation that can be used for activated sludge system design and operation.     

Using the Kinetics of Biological Flocculation and the Limiting Flux Theory for the Preliminary Design of Activated Sludge Systems. II: Experimental Verification

Current activated sludge models consider that the removal of biodegradable organics by suspended growth includes: rapid enmeshment of the organic particles in the microbial floc, hydrolysis of the complex organic molecules into readily biodegradable organic substances, and oxidation of dissolved organic substances. All of the models assume that hydrolysis is the rate-limiting step, but none considers the role that the kinetics of biological flocculation and the sludge-settling characteristics may play in defining the activated sludge operating parameters. Several researchers have studied the kinetics of biological flocculation, and have analyzed its role on the removal of particulate chemical oxygen demand in suspended growth reactors. It has been demonstrated that a large proportion of the organic matter present in sewage can be removed by biological flocculation using short hydraulic retention times and subsequent settling. The first paper demonstrates that the one-dimensional limiting flux theory may be useful for coupling the sludge-settling properties with the aeration tank behavior, and the second paper presents experimental evidence that the proposed model is a reasonable first approximation that can be used for activated sludge system design and operation.     

Chemical Oxygen Demand and the Mechanism of Excess Sludge Reduction in an Oxic-Settling-Anaerobic Activated Sludge Process

A modified activated sludge process, called the oxic-settling-anaerobic (OSA) process, achieved effective reduction in excess sludge production. Its key feature is the insertion of a sludge holding tank in the sludge return circuit to provide an anaerobic sludge zone. Our previous studies suggested that such excess sludge reduction might be associated with an increased sludge decay rate and the effective consumption of organic substrates generated during the retention of the thickened sludge in the sludge holding tank under a low oxidation-reduction potential (ORP) at ?250?mV. To confirm this suggestion, we analyzed the chemical oxygen demand (COD) balance in the sludge holding tank through batch experiments to simulate the sludge concentration, ORP level, and retention time in the sludge holding tank. The COD generated from the sludge reduction in the tank was utilized by organic gas (mainly CH4) production, denitrification, sulfate reduction, and phosphorus release, among which the gas production accounted for 50% of the COD utilization. We confirmed that the mechanism of the excess sludge reduction in the OSA process is through enhancement of the sludge decay rate in the anaerobic sludge zone, which increases the soluble COD level, which in turn is mainly transformed into methane gas and carbon dioxide during denitrification.     

Comparison of PCR and cell culture for detection of enteroviruses in sludge-amended field soils and determination of their transport

PCR and cell culture assays for enteroviruses were conducted on soil samples collected from an experimental farm that had received mesophilic anaerobically digested sludge for the past 7 years. Of 24 samples assayed, 21 samples were positive by PCR, implying that at least some viral nucleic acid sequences remained intact. However, these viral particles were unable to infect the Buffalo Green Monkey cell line used in subsequent cell culture assays. It is significant that positive PCR detection of nucleic acid sequences occurred even though the most recent sludge application was 3 months prior to soil sampling. Viral nucleic acid sequences were detected by PCR at points vertically and laterally displaced from sludge injections, illustrating significant transport of viruses. Rainfall and irrigation events may have contributed to viral transport.     

Effect of the Sonophotocatalytic Pretreatment on the Volume Reduction of Sewage Sludge and Enhanced Recovery of Methane and Phosphorus

In this study, the sonophotocatalytic process, i.e., combination of ultrasonic irradiation (US) and photocatalytic reaction, was proposed as a pretreatment process for the anaerobic digestion of organic sludge in order to drastically reduce the amount of sludge and promote the recovery of methane and phosphorus. Several series of experiments employing different techniques, i.e., sonophotocatalysis (SPC), US, photocatalysis (PC), and thermal treatment, were conducted by using a batch type apparatus. The results of the SPC treatment showed a decrease in sludge volume by about 50% and the synergetic effects of US and PC treatments which were clearly observed as increases in dissolved chemical oxygen demand of sludge filtrate and in phosphorus compounds dissolution from sludge particles. In the SPC process of sewage sludge, the photocatalytic reaction was enhanced by the sufficient disintegration of sludge flocks due to the US treatment. Any pretreatments applied promoted the anaerobic digestion process, however, there was little synergetic effect and the long time SPC treatment resulted in a decrease in the reaction rate.     

Pathogenic micro-organisms in slaughterhouse sludge--a survey

During slaughtering of animals and subsequent meat processing the process water used becomes polluted with organic matter of animal origin (i.e. protein and fat). This organic sludge is, in principle, a product suitable for animal feeding. To investigate the microbiological contamination level of sludge, raw sludge was collected at pig (n = 8) and poultry (n = 5) slaughterhouses. Both flocculated and aerobically activated sludge was monitored. Slaughterhouse sludge was heavily contaminated with Enterobacteriaceae (6.3-10.0 in log10 N/gram dry matter) and enterococci (4.6-7.9). Clostridia were present in sludge at a level of 3.1-5.8 (in log10 N/g DM). Salmonella was present in the sludge from all slaughterhouses examined. Yersinia enterocolitica serotypes O:3 and O:9 were found in sludge from seven out of thirteen slaughterhouses. The prevalence of Campylobacter jejuni/coli was higher in flocculated poultry sludge than in both flocculated pig sludge and aerobically activated pig sludge. Obviously, decontamination of the sludge is mandatory when it is to be applied as a feed constituent, to prevent bacterial cycles from occurring in livestock, as well as the spread of human pathogenic zoonoses like campylobacter, salmonella and yersinia, to minimize loss of protein quality by the microbial breakdown of amino acids and the formation of possible toxic metabolites in sludge during storage.     

高炉喷吹煤粉混加冶金油泥的燃烧性能

 将冶金油泥与煤粉混合用于高炉喷吹可实现油泥资源化利用,提高煤粉燃烧效率。通过TG-MS研究了高炉喷吹煤粉添加污泥后的燃烧特性与气体释放特征,探究油泥有机组分和无机组分对高炉喷吹煤粉燃烧过程的影响。多种检测手段系统考察了油泥的理化性质,并通过TG-MS研究了高炉喷吹煤粉添加污泥后的燃烧特性与气体释放特征。结果表明,油泥组成主要为润滑油等有机物和以Fe₂O₃为主要成分的无机物,其粒度主要集中在0.7~3 μm,孔隙发达且多为介孔。添加油泥可以降低煤粉的着火温度和最大燃烧速率对应的温度,从而改善反应性,同时提高燃烧过程的放热量,使燃料燃烧更加充分,但当油泥添加量过大时,对煤粉燃烧热量影响较低。动力学研究发现,油泥的添加会降低煤粉燃烧反应的活化能,从而使煤粉燃烧更易进行。     

Removal of Refractory Organic Compounds in Liquid Swine Manure Obtained from a Biofiltration Process Using an Electrochemical Treatment

Swine wastewaters contain varied and high amounts of organic matter (proteins, antibiotic compounds, organic acids) which are difficult to oxidize biologically or chemically. The discharge of such effluents is undesirable and can cause excessive oxygen demand in the receiving water. In order to produce an effluent suitable for stream discharge, electrochemical techniques have been explored at the laboratory pilot scale, for refractory residual organic compound removal in liquid swine manure (LSM) following a biofiltration process. Two types of electrolytic cells (monopolar and bipolar electrode cells) using aluminum and mild steel electrodes were studied. Effectiveness was measured in terms of chemical oxygen demand (COD) and biological oxygen demand (BOD) reduction. The amount of residue sludge produced and energy consumed have been also considered. Results showed that the best performances of COD and BOD removal from LSM were obtained using either aluminum bipolar (Al-BP) electrodes or mild steel monopolar (Fe-MP) electrodes operated at current intensities of 0.5 and 2.0?A, respectively, through 30?min of treatment. The COD removal yields varied from 65 to 68%, whereas BOD removal reached 87%. The optimal conditions determined for organic compound removal, including energy consumption and metallic sludge disposal, involved a total cost of only $0.24?and?$0.29?United?States/m3 of treated LSM. The treatment using the Fe-MP system was found to be more economical and practical than the chemical treatment using FeCl3 as a coagulating agent.     

不同pH值下胞外聚合物对污泥脱水性能及束缚水含量的影响

研究了不同pH值下污泥脱水性能和束缚水含量的变化,通过测定污泥调理过程中各层胞外聚合物(S-EPS、LB-EPS和TB-EPS)中蛋白质和多糖的含量、S-EPS中有机官能团以及有机酸的含量,探讨了胞外聚合物对污泥脱水性能及束缚水含量的影响.酸性条件下,污泥的脱水性能明显好于中性条件,并且pH值为3.03时,污泥滤饼含水率(WC)和毛细吸水时间(CST)均降至最低,分别为60.8%和25.4 s;碱性条件下,污泥中束缚水的含量明显增加,WC和CST均大幅升高,污泥脱水性能恶化.酸碱的加入导致污泥中TB-EPS含量降低,LB-EPS和S-EPS含量升高,并且EPS各层组均与WC、CST以及束缚水含量具有很强的相关性,其中S-EPS与污泥脱水性能以及束缚水含量的相关性最显著.酸碱调理过程中,部分EPS水解生成有机酸等小分子有机物,S-EPS中有机官能团的总量和种类都有明显增多.      

Statistical Comparison of Bioassays for Assessment of Toxicity of Organic Components of Wastewater to Activated Sludge

In aquatic toxicity testing, no single test species responds appropriately to all toxicants. Therefore test batteries consisting of several individual assays are becoming more common. The species comprising a test battery should be representative of the entire system of interest. Each assay should be complementary to other components in the test battery and the test battery should not include redundant tests. We studied the selection of test battery components for the assessment of the toxicity of organic chemicals to activated sludge. The assays considered were the continuous Shk1, Microtox, Polytox, activated sludge respiration inhibition, Nitrosomonas, and Tetrahymena assays. The correlations between the toxicity data obtained from these assays were analyzed by examining the correlation matrix and by principal component analysis. These statistical methods showed that the Nitrosomonas assay should be included in test batteries plus one of the remaining five assays for assessing toxicity of organic compounds to activated sludge.