基于钙基吸收剂的旋风烟道内垃圾焚烧烟气脱氯特性研究  

Study on Dechlorination Characteristics of Waste Incineration Flue Gas in Cyclone Flue Based on Ca-Based Sorbents

作　　者：邱华禹 陈冬梅[1,2] 何智 冉景煜[1,2] 牛俊天 QIU Hua-Yu;CHEN Dong-Mei;HE Zhi;RAN Jing-Yu;NIU Jun-Tian(Key Laboratory of Low-grade Energy Utilization Technologies and Systems,Chongqing University,Chongqing 400044,China;School of Energy and Power Engineering,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学低品位能源利用技术及系统教育部重点实验室,重庆400044 [2]重庆大学能源与动力工程学院,重庆400044

出　　处：《工程热物理学报》2022年第3期712-719,共8页Journal of Engineering Thermophysics

基　　金：重庆市重点产业共性关键技术创新专项(No.cstc2016zdcy-ztzx20006)。

摘　　要：如何在高温区脱除HCl气体,减轻炉排炉垃圾焚烧发电中的高低温腐蚀,提高余热锅炉效率是急需解决的关键问题。于此,作者提出了垃圾焚烧烟气旋风烟道预处理技术,并采用CFD方法研究了旋风烟道内CaCO_(3)颗粒的脱氯特性。结果表明,旋风烟道内脱氯反应主要发生在导流体段,并且随着颗粒粒径d_(cc)以及喷射速度v_(cc)的增加,CaCO_(3)颗粒在导流体段的平均停留时间先增加后减小。旋风烟道内CaCO_(3)颗粒的脱氯效率随着Ca/Cl摩尔比α的增加而增加,当α>8时,脱氯效率不再明显增加,随着颗粒粒径d_(cc)、入口烟气温度T_(g)、入口烟气流速v_(g)的增加而减小。综合考虑各种因素,较佳的脱氯反应条件为α=8,d_(cc)=35~45μm,T_(g)=850℃,v_(g)=15 m/s,v_(cc)=60 m/s,可使旋风烟道内的脱氯效率达到74.4%以上。Incineration plays an increasingly important role in the treatment of municipal solid waste.It will be the main way to deal with municipal solid waste in the future,but secondary pollution is inevitably during the incineration,and chlorine is one of the important elements that cause secondary pollution.The presence of chlorine will promote the volatilization of heavy metals and the synthesis of dioxins,cause the corrosion of heating surface at high and low temperatures,and limit the further improvement of steam parameters.Therefore,the removal of HCl from incineration flue gas at high temperatures is very important.For this problem,this study proposes adiabatic cyclone flue arranged at the exit of the first-stage furnace of grate furnace,and the calcium are sprayed into the flue.Under the effect of the swirling flow,the reaction time of absorbent and flue gas is extended,so that the reaction is more sufficient,and at the same time,the reaction products and the unreacted particles can be separated.In this paper,the dechlorination characteristics of CaCO_(3) particles in cyclone flue were studied by CFD method,combining discrete phase model(DPM)and particle surface reaction model.The results show that the dechlorination reaction mainly occurs in the vortex finder section.With the increase of particle diameter(d_(cc))and injection velocity(v_(cc)),the average residence time of CaCO_(3) particles increases first and then decreases in vortex finder section,and the impact of injection velocity was small.The dechlorination efficiency of CaCO_(3) particles increases with the increase of Ca/Cl(α),whenα>8,the dechlorination efficiency no longer increases significantly.With the increase of particle diameter(d_(cc)),inlet flue gas temperature(T_(g)),and inlet flue gas velocity(v_(g)),the dechlorination efficiency decreases,and the temperature has the smallest effect on the dechlorination efficiency.Considering economy,particle separation efficiency,dechlorination efficiency,dioxin pyrolysis comprehensively,the better react

关 键 词：烟道气 吸附剂 脱氯效率 旋风烟道 数值模拟 

分 类 号：TK09[动力工程及工程热物理]