气力输送中PVC粉体静电带电影响因素

Factors affecting electrification of PVC powder in pneumatic conveying

为了研究工业中常用的聚氯乙烯(PVC)粉体在气力输送过程中的静电影响因素,以PVC粉体为输送对象,以荷质比为指标,研究PVC粉体的下料质量流量、气流速度、气单位体积的气体中所含粉体的质量和球阀开度对粉体带电的影响。结果表明:当下料质量流量一定时,PVC粉体的荷质比会随气流速度增大而增大,随球阀开度减小而减小;当气流速度一定时,PVC粉体的荷质比会随下料质量流量增大而减小,输送颗粒的荷质比存在临界值为0.2μC/kg;当单位体积的气体中所含粉体的质量一定时,下料质量流量对PVC粉体荷质比影响要大于气流速度对其的影响;当下料质量流量一定时,PVC粉体的荷质比会随球阀开度的减小而减小。

In order to study the electrostatic influence factors of polyvinyl chloride(PVC)powder commonly used in industry during pneumatic conveying,this paper takes PVC powder as the conveying object,and takes charge mass ratio as the index to explore the influence of PVC powder's feeding speed,air flow speed,the mass of the pwder contained in the unit volume of gas and ball valve opening on powder electrification.The results show that when the feeding speed is constant,the charge mass ratio of PVC powder increases with the increasing of airflow speed and decreases with the decreasing of ball valve opening.When the airflow speed is constant,the charge mass ratio of PVC powder decreases with the increasing of the feeding speed,but there is a critical value of the charge mass ratio of conveying particles,which is O.2μC/kg.When the the mass of the pwder contained in the unit volume of gas is constant,the charge mass ratio of PVC powder decreases with the increasing of blanking speed and airflow speed.When the feeding speed is constant,the charge mass ratio of PVC powder decreases with the decreasing of ball valve opened.