电晕驻极滤袋对荷电微细颗粒物捕集效率  

Collection efficiency of electret bag filter for charged fine particulate matter

作　　者：吕超 杨小川 朱冕 柳静献 LYU Chao;YANG Xiao-chuan;ZHU Mian;LIU Jing-xian(Filter Test Center,School of Resources&Civil Engineering,Northeastern University,Shenyang 110819,China;Shanghai Baoye Group Corp.,Ltd,Shanghai 200000,China)

机构地区：[1]东北大学资源与土木工程学院,滤料检测中心,辽宁沈阳110819 [2]上海宝冶集团有限公司,上海200000

出　　处：《中国环境科学》2024年第2期663-669,共7页China Environmental Science

基　　金：国家十四五重点专项(2022YFC2503200);国家自然科学基金资助项目(52174215);辽宁省兴辽人才计划(XLYC2002091);辽宁省揭榜挂帅科技攻关专项(2021JH1/10400023);浙江省重点研发计划项目(2020C03089)。

摘　　要：本文利用单针-板电极负直流高压电晕放电装置对针刺毡滤袋进行电晕驻极处理,设计搭建了由线-板式预荷电器和驻极滤袋集尘装置组成的复合电/袋过滤实验平台,系统的研究了电晕驻极滤袋对未荷电、单极荷正电、单极荷负电以及双极荷电的0.3~10μm微细颗粒物捕集效率,对比了不同风速条件下驻极滤袋对不同荷电类型微细颗粒物捕集效率的稳定性.实验结果表明:相比于原始滤料捕集未荷电颗粒物,库仑作用的引入使得驻极滤料捕集荷电颗粒物具有更高的效率,尤其是对于粒径0.3μm颗粒物提升效果最为明显,荷正电、荷负电和双极荷电使其捕集效率从79.9%分别提升到99.9%、99.3%和98.6%;基于库仑力的静电捕集效率还能够补偿由于风速增大而造成的机械捕集效率降低幅度,对于粒径0.3μm颗粒物,荷正电、荷负电和双极荷电使其捕集效率差值从9.4%分别降低到0.06%、0.2%和5.2%.更具体地说,即库仑引力作用强于库仑斥力作用,且两者均优于异相荷电凝并作用.此外,利用扫描电镜技术分析了不同荷电类型颗粒物在驻极滤袋表面沉积的微观形貌结构,提出了相应的尘饼生长理想化模型用于进一步解释以上实验结果.该研究结果可为进一步发展静电-机械双效捕集脱除微细颗粒物提供参考.In this study,the bag filters were charged by single needle corona discharge with negative DC power supply,and a hybrid electrostatic filter comprised of pre-charger and electret bag filter were designed and manufactured.The collection efficiency of electret bag filter for uncharged,positively charged,negatively charged and bipolarly charged particles(0.3~10μm)were systematically studied,and the stability of collection efficiency for particles with different charge types were compared under different flow velocity conditions.Compared to raw bag filter for capturing neutral particles,the collection efficiency of electret bag filter for charged particles was higher.Especially for the particles with a size of 0.3μm,the collection efficiency increased from 79.9%to 99.9%(positive charge),99.3%(negative charge)and 98.6%(bipolar charge),respectively.The electrostatic collection efficiency compensates for the reduction of mechanical collection efficiency with the increase of flow velocity.For the 0.3μm particles,the decrement of collection efficiency decreased from 9.4%(neutral)to 0.06%(positive charge),0.2%(negative charge)and 5.2%(bipolar charge),respectively.More specifically,the enhancement of collection efficiency by coulomb attraction was stronger than that by coulomb repulsion,and both were superior to the agglomeration behavior.Three filter cake models were inferred by SEM to systematically explain this experimental phenomenon.These findings are very important for further studying the combination of electrostatic and mechanical collection mechanism of bag filter for fine particulate matter.

关 键 词：驻极滤袋 细微颗粒物 荷电 捕集效率 尘饼 

分 类 号：X513[环境科学与工程—环境工程]