模拟垃圾焚烧过程中氯对铅动态挥发特性的影响  

Effect of chlorides on plumbum dynamic volatilization during simulated municipal solid waste incineration

作　　者：张帅毅[1] 黄亚继[1] 王昕晔[1] 严玉朋[1] 刘长奇[1] 陈波[1] 

机构地区：[1]东南大学能源热转换及其过程测控教育部重点实验室,江苏南京210096

出　　处：《浙江大学学报（工学版）》2016年第3期485-490,498,共7页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(51476031);高等学校博士学科点专项科研基金资助项目(20130092110007)

摘　　要：使用管式炉模拟炉排炉内垃圾焚烧过程,收集连续变化时段内的飞灰并对其进行分析,研究垃圾中有机氯（PVC）和无机氯（NaCl）对铅（Pb）动态挥发特性的影响.在从室温（25℃）至900℃的焚烧过程中,PVC对Pb挥发的促进作用略强于NaCl,但是两者发生作用的温区完全不同.PVC的作用温度低于500℃,而NaCl的作用温度为800~900℃.进一步的机理研究表明：PVC通过间接氯化促进Pb挥发,NaCl则通过直接氯化促进Pb挥发.PVC在200~300℃开始释放HCl,通过HCl将高熔点的PbO氯化为低熔点的PbCl2,从而导致Pb挥发温度提前到500~600℃.NaCl在焚烧过程中不释放含氯气体,而是在800~900℃下直接与SiO2、Al2O3和PbO反应生成PbCl2,从而促进Pb的挥发.The incineration process in grate furnace was simulated by the waste combustion in a tube furnace.The effect of organic chlorine（PVC）and inorganic chlorine（NaCl）on the dynamic volatilization characteristic of Pb were investigated according to the continuous collection of fly ash during incineration from room temperature（25℃）to 900℃.The organic chlorine had more significant impact on Pb volatilization than inorganic chlorine.But the temperature zones where they worked were totally different.The effective temperature of PVC was under 500℃,but the effective temperature of NaCl was between 800℃and 900 ℃.The further mechanism study indicates that PVC promotes Pb volatilization by indirect chlorination,while NaCl promotes Pb volatilization by direct chlorination.PVC begins to release HCl at the temperature of 200℃to 300℃and transfer chlorinate PbO to PbCl2 during the incineration process,leading to the volatilization temperature of Pb at 500℃to 600℃.During the incineration process,NaCl does not release chloride gas,but chlorinate PbO at the temperatnre of 800℃to 900℃ with the combination of SiO2 and Al2O3to promote the volatilization of Pb.

关 键 词：管式炉 有机氯(PVC) 氯化钠(NaCl) 铅(Pb) 挥发 

分 类 号：X705[环境科学与工程—环境工程]