电厂燃煤飞灰固化脱硫污泥重金属铅特性研究  

Study on the Characteristics of Heavy Metal Lead in Desulfurization Sludge Solidified by Coal-Fired Fly Ash in Power Plant

作　　者：张宏伟 张永生[1] 汪涛[1] 王家伟[1] ZHANG Hongwei;ZHANG Yongsheng;WANG Tao;WANG Jiawei(School of Energy,Power and Mechanical Engineering,North China Electric Power University,Changping District,Beijing 102206,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,北京市昌平区102206

出　　处：《发电技术》2024年第3期527-534,共8页Power Generation Technology

基　　金：国家自然科学基金项目(52276110)。

摘　　要：【目的】燃煤电厂脱硫污泥中重金属富集显著,降低脱硫污泥中重金属含量十分必要。【方法】提出利用电厂飞灰固化脱硫污泥重金属的思路,并和常见固化剂开展对比。【结果】以铅为对象,在水泥、飞灰、螯合剂二硫代氨基甲酸酯(dithiocarbamate,DTC)和螯合剂三聚硫氰酸三钠盐(TMT-15)中,飞灰对脱硫污泥中铅固化效果最好;不同飞灰及脱硫污泥固化效率在40%~100%。机理分析表明,类似于水泥,飞灰化学成分主要含有SiO2、Al2O3、CaO、Fe2O3等,可与脱硫污泥发生水化反应等,生成对重金属固化稳定有利的水化硅酸钙C-S-H等水化产物及钙矾石等物质,同时生成物对重金属铅等具有吸附作用。【结论】在燃煤电厂脱硫污泥中掺入一定比例的飞灰可以实现铅的固化稳定,为脱硫污泥从危险固废降低为一般固废提供了方法。[Objectives]The enrichment of heavy metals in desulphurization sludge of coal-fired power plant is significant,so it is necessary to reduce the content of heavy metals in desulfurization sludge.[Methods]This paper put forward the idea of solidifying heavy metals in desulfurization sludge with fly ash from power plants and compared with common curing agents.[Results]Among cement,fly ash,chelating agent DTC(dithiocarbamate)and chelating agent TMT-15(trisodium thiocyanate),fly ash has the best solidification effect on lead in desulfurization sludge.The solidification efficiency of different fly ash and desulfurization sludge is between 40%and 100%.The mechanism analysis shows that,similar to cement,the chemical composition of fly ash mainly contains SiO2,Al2O3,CaO and Fe2O3,etc.,which can react with desulfurization sludge to generate hydration products such as hydrated calcium silicate C-S-H and ettringite,etc.It is beneficial to the solidification of heavy metals.The products can adsorb heavy metals such as lead.[Conclusions]It can be seen that adding a certain proportion of fly ash into the desulfurization sludge of coal-fired power plants can realize the solidification and stability of lead,which provides a method for reducing the desulfurization sludge from dangerous solid waste to general solid waste.

关 键 词：燃煤电厂 脱硫污泥 飞灰 稳定固化 

分 类 号：TK09[动力工程及工程热物理]