污泥热解处理过程中重金属迁移与转化规律综述

归纳总结了各种污泥重金属化学形态分析方法的发展和优缺点、重金属化学形态与生物毒性及生物有效性的关系、污泥重金属评估指数;并重点阐述了对于污泥热解过程中重金属迁徙转化的影响因子,包括污泥自身理化特性、热解终温与加热速率、催化剂、添加剂等对于不同种类重金属的作用规律,为在污泥热解处理中重金属未来的研究趋势方向提供了科学参考。     

谈生物淋滤去除污泥中重金属的方法

随着社会经济的不断发展,太原市污水排放量迅速增加,污泥产量也随之增加。土地利用是目前最有潜力的污泥处置方法,但是受到重金属的限制。针对太原市污泥中重金属的特性,摸索用生物淋滤去除重金属的方法。     

重金属在环境中的化学形态分析探寻

对于重金属污染风险以及生物有效性产生决定性作用的就是其在环境中的形态与迁移转化。文章将影响重金属形态环境条件及结合物特点作为着手点,全面分析重金属在环境当中同有机物和无机矿物质的交互作用机理,阐述了重金属形态分析的研究方法。     

土壤重金属污染生物修复研究进展

土壤中的重金属因积累效应威胁人类健康,其修复问题日益受到重视,生物修复技术是土壤重金属污染修复的重要方法。对土壤中的镉、铅、锰、铜生物修复研究现状进行了简述,并对以后该领域的研究趋势进行介绍。     

城市土壤重金属污染现状及治理方法

综述城市土壤重金属污染来源及危害,归纳常用治理方法,并介绍生物修复法,指出今后研究的重点是建立城市土壤重金属污染源预警信息系统,有针对性地开展污染治理措施研究。     

电镀污泥热处理重金属的形态变化研究-Sposito法

电镀污泥中重金属的含量及其生物有效性是对环境的重要限制因素。采用改进的Sposito顺序浸提法考察了不同温度(200,400,600,800)℃焚烧电镀污泥残渣中重金属Cu、Ni的赋存形态分布特征。结果表明:焚烧处理具有显著的减量化效应,残渣中的Cu、Ni重金属呈现出富集效益,重金属Cu的残渣态为73.39%,低于Ni(93.03%)。形态分析表明,随着焚烧温度的提高,生物可利用性形态含量呈现下降趋势,实现了不稳定态向稳定态的转化。     

鸽粪基生物炭对土壤重金属形态的影响

基于鸽粪基生物炭的优良特性,进行模拟重金属污染土壤修复试验,研究了其对Cu、Zn、Pb、Cd的作用效果及土壤中赋存形态转化的影响.结果表明:鸽粪基生物炭中的CO_3^2-及OH-可与溶液中的Pb反应产生Pb的碳酸盐和氢氧化物沉淀;在重金属复合污染土壤中添加生物炭后,生物有效性最强的可交换态Cu、Zn、Pb、Cd含量分别降低98.48%、61.79%、89.15%和32.76%.生物炭中的灰分使土壤pH值显著升高(2.5~3.13),从而增加了碳酸盐结合态含量;而土壤有机质含量的升高(37.75%~178.43%)直接导致有机结合态含量增加;和500℃生物炭相比,400℃生物炭有机质含量更高,灰分含量更低.本研究的结果可以为鸽粪基生物炭在重金属复合污染土壤修复中的应用提供一定的理论基础,也为鸽粪固废处理开拓了新的思路.     

浅析化验废液的处理

对CH3OH化验室中的废液,废气,含重金属废液,含H2S,CO废气,含氧化剂、还原剂的废液,含酸、碱、盐类物质的废液等化验室无机类废液的收集、处理方法及注意事项进行了分析.     

沸石对猪粪沼气发酵特性及沼渣、沼液中重金属Zn的影响

为减少重金属污染,以猪粪为发酵原料,采用厌氧发酵技术进行试验。结果表明:添加沸石对沼气发酵产气量、甲烷含量影响不大;厌氧发酵后,添加沸石组重金属Zn的89.88%存在于沼渣中,10.12%存在于沼液中;Zn总量下降了32.41%,下降幅度高于空白对照组;厌氧发酵后,沼渣、沼液中的重金属形态都以残渣态为主,添加沸石组的沼渣、沼液中残渣态的比例高于空白对照组;厌氧发酵后,空白组沼渣中重金属Zn的有效态含量占32.63%,添加沸石组重金属Zn的有效态含量占29.12%。添加沸石有利于降低重金属Zn的生物有效性,因此,建议在厌氧发酵过程中添加重金属钝化剂,以此减少沼肥回田后重金属污染的风险。     

低温等离子体在垃圾焚烧烟气治理中的应用

随着城镇化的速度加快,人口集中度逐渐提升,伴随而来的生活垃圾增量也不断提升,因此垃圾焚烧是处理垃圾的主流方向。垃圾焚烧烟气中二噁英及重金属含量较高,二噁英对生物和环境影响尤其大,由于存在生殖毒性和遗传毒性而备受公众广泛关注。因此二噁英和重金属的治理需要进一步提高。     

重金属处理技术研究进展

重金属是水环境中的主要污染物之一,随着社会的进步和工业的发展,含重金属离子废水的排放量在逐渐增多,主要来自电镀、采矿、冶金、化工等工业,具有潜在的危害性.近些年来,处理重金属废水的技术发展迅速,吸附法因为速度快、操作简单、吸附材料来源广等优点被人们广泛应用,尤其是金属离子印迹技术.目前为止,已经成功制备出了以Ni2＋、Cu2＋、Cd2＋、Zn2＋等多种金属离子为模板离子的金属离子印迹聚合物,并在环境分析和医药领域有着广泛的应用.     

垃圾综合治理焚烧过程中重金属的迁移规律

对实际运行中的垃圾焚烧炉灰渣的重金属含量和分布等物理特性进行测试分析，对各种元素间重金属分布特性的相关性及重金属迁移对运行设备造成的影响进行了详细的探讨，为灰渣填埋的重金属控制和化学稳定性措施与灰渣材料化治理利用提供基础。     

The kinetics of vaporization of a heavy metal from a fluidized waste by an inverse method

This study addresses the emission of heavy metals during the incineration of municipal solid waste. A global method was developed to determine the vaporization rate of the metal from the on-line analysis of exhaust gas. This method differs from direct models, which predict the time course of the metal concentration in the gas from the vaporization rate profile, but which are not practicable because this vaporization rate cannot be measured in real incinerators burning real wastes. The method is based on the determination of the global rate of release of heavy metal from the combustion of model wastes in a fluidized bed. It is an inverse method, which involves only the measured concentration of heavy metal in the exhaust gases and a model developed at the reactor scale. The thermal treatment of model wastes spiked with a metal was performed in a laboratory- scale fluidized bed. In fact, a solid matrix derived from real waste was dosed with Cd, Pb, or Zn and burned to simulate the metal’s release during the incineration of municipal solid waste. An on-line analysis system was linked to the gas outlet of the reactor, and the metal’s vaporization was tracked successfully by continuously measuring by inductively coupled plasma optical emission spectroscopy (ICP-OES) the relative concentration of the metal in exhaust gases. On the theoretical front, a bubbling bed model was developed and validated to calculate the metal’s vaporization rate from its concentration-time profile in the outlet gas. The inverse method consists in identifying these vaporization rates at the particle level from only the on-line diagnostic results and using the model, whatever the waste considered. The data obtained may be used in any process, in which wastes are heated rapidly (several hundreds of degrees per second), as in fluidized beds.     

纳米TiO2光催化剂负载和光催化反应器的研究进展

纳米TiO2光催化氧化技术在废水处理领域具有广阔的应用前景。将纳米Ti02负载到某种载体上，并设计出高效的光催化反应器是实现光催化氧化技术处理废水实用化的关键技术之一。本文对纳米TiO2光催化剂负载所用的载体、负载型光催化剂的制备方法及其光催化反应器进行了综述。     

Cu^2＋Zn^2＋Ni^2＋Cr^3＋对皮革废水厌氧消化抑制作用的研究

系统地研究了Ｃｕ２＋、Ｚｎ２＋、Ｎｉ２＋和Ｃｒ３＋四种金属离子加入浓度、溶解态离子浓度与皮革废水厌氧消化产气量的关系，其毒性大小的顺序为Ｃｒ３＋＞Ｎｉ２＋＞Ｃｕ２＋＞Ｚｎ２＋，提出维持正常厌氧消化时体系中溶解态离子浓度的上限，为厌氧生物处理皮革废水的实际应用提供了一定的科学依据。     

丙烯腈废水焚烧余热锅炉结渣分析与改造研究

针对丙烯腈装置废水焚烧余热锅炉严重结渣堵管的技术难题,通过试验和理论分析研究结渣成分和成因;根据分析结果,对废水焚烧余热锅炉结构提出具体的改进措施,结合具体的工程应用实例,证明改进结构对于回收废水焚烧余热的有效性。     

Land application of organic waste – Effects on the soil ecosystem

Growing populations and the increasing use of existing resources has led to growth in organic waste emissions. Therefore, a sustainable approach to managing this waste has become a major concern in densely populated areas. Biological treatment is an efficient method for reducing the amount of organic waste, and for producing energy. A large number of biogas plants and compost facilities that use organic waste as a substrate for electricity and fuel production are being built around the world. The biological treatment process in these plants produces large amounts of organic waste, and there is therefore a growing need to find a sustainable use for this material. Organic waste, such as biogas residues and compost can be a valuable fertilizer for agricultural soils. They can serve as a source of plant nutrients and can also improve soil structure and water holding capacity. However, as organic residues are known to contain both heavy metals and organic contaminants there is a need for long term field experiments to ensure that soil and plant quality is maintained. In order to investigate the potential risks and benefits of using organic waste in agriculture, an 8 year field experiment was established in central Sweden. Under realistic conditions, compost and biogas residues from source-separated household waste were compared with traditional mineral fertilizer. We examined crop yield and soil chemical and microbiological properties. The main conclusion from the field experiment was that biogas residues resulted in crop yields almost as high as the mineral fertilizer NPS. In addition, several important soil microbiological properties, such as substrate induced respiration, potential ammonium oxidation and nitrogen mineralization were improved after application of both biogas residues and compost. Moreover, no negative effects could be detected from using either of the organic wastes. In particular the genetic structure of the soil bacterial community appeared to resist changes caused by addition of organic waste.     

电泳涂装废水处理技术

叙述了涂装工艺、涂装废水性质以及废水处理技术,指出,废水的成分复杂,排放无规律,水质变化大,废水先经微电解氧化后加药中和沉淀,再经AO生化处理,活性炭吸附过滤后出水达到GB8978-1996污水综合排放标准中的一级排放标准。     

生物氧化技术除臭在污水处理厂中的应用

长庆石化运行三部污水区块现有碱渣预处理单元、高浓度污水处理系统、低浓度污水处理系统等8套污水、污泥处理设施。在生产过程中,无组织排放的废气对周围环境造成一定影响。废气主要组成为硫化氢、氨气、二甲苯、苯、甲苯、酚、烃类、甲硫醇、甲硫醚、二甲二硫等。对各种气体治理技术进行比对,选取生物氧化法工艺,该工艺集生物液滤、生物滴滤和生物氧化技术于一身,具有流程简单,装置占地少,减除效果明显,不产生二次污染,以及系统启动速度快、抗污染物冲击能力强、污染物去除效率高、运行成本低等优点。污染气体经过生物氧化系统处理后,在工况良好情况下,处理效果明显,可同时去除多种污染物组分。排放气体中VOC含量明显低于排放标准限值,显示出良好的处理效果。但由于系统补水为新鲜水(电导率约为1800μS/cm),导致生物氧化后系统排水电导率较高。准备将污水反渗透水引入生物氧化系统,以更好地提高生物氧化工艺的处理效果。     

A particulate model of solid waste incineration in a fluidized bed combining combustion and heavy metal vaporization

This study aims to develop a particulate model combining solid waste particle combustion and heavy metal vaporization from burning particles during MSW incineration in a fluidized bed. The original approach for this model combines an asymptotic combustion model for the carbonaceous solid combustion and a shrinking core model to describe the heavy metal vaporization. A parametric study is presented. The global metal vaporization process is strongly influenced by temperature. Internal mass transfer controls the metal vaporization rate at low temperatures. At high temperatures, the chemical reactions associated with particle combustion control the metal vaporization rate. A comparison between the simulation results and experimental data obtained with a laboratory-scale fluid bed incinerator and Cd-spiked particles shows that the heavy metal vaporization is correctly predicted by the model. The predictions are better at higher temperatures because of the temperature gradient inside the particle. Future development of the model will take this into account.