湿度对袋式除尘性能的强化研究

Effects of humidity on dust removal intensification of bag filters

针对袋式除尘过程中运行阻力较高的问题,提出了一种通过调控湿度、改变颗粒间作用力来强化袋式除尘性能的方法,系统考察了湿度对颗粒间作用力的影响;为扩大研究的普适性,采用在高湿环境下更不易形成液桥的疏水性滑石粉作为模拟粉尘,并采用聚四氟乙烯(PTFE)覆膜滤料作为过滤介质,研究了湿度对滤饼空隙率、滤饼过滤阻力、荷尘量、除尘效率等除尘性能的影响。结果表明,颗粒间黏附力随湿度增加而增大。一定湿度范围内,含尘气体湿度越高,过滤阻力越小,除尘性能越好。通过提高湿度,在最优条件下,单位荷尘量下滤饼过滤阻力可降为原来的6%。

A method of inter-particle force adjustment by regulating humidity was proposed to reduce filtration resistance and achieve better bag filter performance. Effects of humidity on inter-particle forces were studied. Hydrophobic talcum powder not easy to form liquid bridge under high humidity was used as model dust for universal application, and a poly tetrafluoroethylene (PTFE) microporous membrane was used as filter media. Effects of humidity on bag filter performance were investigated by measuring cake porosity, cake filtration resistance, cake area load and dust removal efficiency. The results show that inter-particle forces increase with the increase of humidity. The filtration resistance decreases and the bag filter performance enhances as humidity increases within certain range. The cake filtration resistance of unit dust loading can be reduced to 6% under optimal conditions.