烧结烟气钙基脱硫灰微量元素的浸出特性研究  

Research on the leaching characteristics of trace elements in sintering flue gas calcium-based desulfurization ash

作　　者：朱哲[1] 任爱玲[1] 崔素玲[2] 郭斌[1] 贡丽鹏[1] 郭琳[3] 

机构地区：[1]河北科技大学环境科学与工程学院,河北省固体废物资源化工程技术研究中心,石家庄050018 [2]河北省科技厅,石家庄050018 [3]石家庄市环境监测中心,石家庄050011

出　　处：《安全与环境学报》2010年第6期36-40,共5页Journal of Safety and Environment

基　　金：国家高技术研究发展计划(863)项目(2007AA061702)

摘　　要：通过浸出特性试验,分别以去离子水和3种不同pH值的酸性缓冲溶液作浸取剂,研究5种重金属Cu、Zn、Pb、Cd、Ni与F在密相法、循环流化床烧结烟气钙基脱硫灰中的质量浓度分布情况及浸出规律。结果表明,烧结烟气钙基脱硫灰不具有腐蚀性,其重金属和F^-的浸出量与浸出液pH值密切相关,易在酸性条件下浸出,脱硫灰自身的碱性对其重金属等微量元素的浸出质量浓度亦有较大的影响。烧结烟气钙基脱硫灰中微量元素的质量浓度均远低于《危险废物鉴别标准浸出毒性鉴别》(GB 5085.3—2007)规定值,不属于具有浸出毒性的危险废物。脱硫灰中Pb^(2+)、Ni^(2+)、Cd^(2+)的浸出质量浓度稍高于西德的固体废弃物填埋标准,在脱硫灰处置时应关注其中Pb、Ni、Cd可能带来的潜在危害。Leaching tests have been performed on sintering flue gas desulphurization （FGD） calcium-based ash from Dense tower and circulating fluidized bed desulfurization in order to study concentration distribution and the law of leaching of five targeted heavy metals （ Cu, Zn, Pb, Cd, Ni） and F in ashes, and the de-ionized water and three different pH values of buffer solution as leaching agent were used respectively in this study. The samples are subjected to a leaching test, in which sintering FGD ash is shaken with water or buffer solution in a liquid to solid ratio （L/S） of 10 for 24 h at room temperature. The relationships between the concentration of trace element in ash and the pH value of leaching agents are investigated. The results of our work indicate that the leaching quantity of heavy metals and F- which could be easily leached in the acidic leaching conditions is closely related with the pH values of leachate. Their alkaline of ashes themselves has a greater influence on concentration of trace elements leaching. The lower the alkalinity of the ash itself, the higher the concentration of leaching element will be. The leaching results from our experiments show that pH values of leachate in FGD ash do not exceed the standard value prescribed in ＂Identification standards for hazardous wastes-Identification for corrosivity＂ （GB 5085.1--2007）, where the ash is not a corrosive substance, and both the concentrations of heavy metals and F- in sintering FGD calcium-based ash prove to be all lower than that of standard of ＂Hazardous Waste Iden- tification Standard-leaching Toxicity Identification＂ （GB 5085.3-- 2007） for extraction toxicity. The leachate concentration in sintering FGD ash is in line with solid waste landfill standards in West Germany, except that the concentrations of Pb^2＋ , Ni^2＋ and Cd^2＋ are slightly higher, so more attention should be paid to the potential hazard of FGD ash brought about by Pb, Cd and Ni. Thus, it can be seen that the above investigation and ana

关 键 词：环境工程学 烧结烟气 脱硫灰 微量元素 浸出特性 

分 类 号：X705[环境科学与工程—环境工程]