摘要
建立高温线板式静电除尘实验系统,将某干法水泥窑尾粉尘作为实验样品,测试粉尘比电阻.通过X射线荧光分析、场发射扫描电镜及马尔文激光粒度仪分析粉尘的化学成分、形貌及粒径分布特性,研究373~773K下静电除尘器对水泥窑尾粉尘的脱除规律.结果表明:水泥窑尾粉尘CaO质量分数高达42.91%,K2O与Na2O质量分数低至0.57%、0.16%,导致粉尘比电阻的最高值达到1.75×1013Ω·cm.粉尘脱除效率随温度的升高先下降后上升,在423~673K高比电阻段(>1012Ω·cm),粉尘脱除效率低于90%.水泥窑尾粉尘PM1.0颗粒粒子数密度约占颗粒总数目的87.5%,373K下,PM1.0脱除效率为82.1%,明显低于PM2.5、PM10脱除效率的95.1%、95.7%,但高温强化了细颗粒的扩散荷电;773K下,PM1.0脱除效率与PM2.5、PM10的差距减小.增大比收尘面积可以有效地提高高温下水泥窑尾粉尘的脱除效率.
A wire-plate electrostatic precipitator was constructed to analyze the particle collection characteristics from 373 Kto 773K.The resistivity,chemical composition,morphology and particle size distribution of cement kiln ash were analyzed.Results show that CaO mass fraction of the cement kiln dust is 42.91%,and Na2O/K2 O mass fraction is 0.57%/0.16%,the maximum resistivity is 1.75×1013Ω·cm at 453 K.Particle removal efficiency first decreases,and then increases with the increasing temperature.The removal efficiency is below 90% at temperatures from 423 Kto 673K,because ash resistivity under these temperatures is larger than 1012Ω·cm.The number fraction of PM1.0is 87.5%to the total cement kiln fly ash particles,and the removal efficiency of PM1.0is 82.1% at 373 K,much lower than 95.1%、95.7%for PM2.5and PM10.PM2.5and PM10 removal efficiencies decrease more rapidly with the increasing temperature than PM1.0,for high temperature strengthens diffusion charge of fine particles.Cement kiln ash removal efficiency can be improved by enlarging the specific collecting area of high-temperature electrostatic precipitator（ESP）.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2017年第10期1959-1966,共8页
Journal of Zhejiang University：Engineering Science
基金
杭州市产学研合作资助项目(G20150101)
中央高校基本科研资助项目(2016FZA4009)
国家"973"重点基础研究发展规划资助项目(2013CB228504)
国家"863"科技支撑计划资助项目(2015BAA05B02)
关键词
水泥窑尾
高温气体
粉尘比电阻
粒径分布
静电除尘(ESP)
cement kiln
high temperature gas
ash resistivity
particle size distribution
electrostatic precipitator（ESP）
