静电除尘器收尘极板上粉尘沉积与电流分布特性

静电除尘器收尘极板上沉积粉体的击穿将严重影响除尘器的技术性能．本文应用电介质极化理论和气体放电理论，在自制的实验装置上详细分析了沉积粉体的堆积模式、粉体表面电位的形成以及粉体击穿时的电压、电流特性．研究表明，收尘极板上沉积粉体的堆积与电流密度密切相关，通常以密实堆积为主．沉积粉体的表面电位达到某一极限值时将导致粉体间空气隙的击穿．粉体击穿时电流骤增的原因主要有：击穿通道形成后大量沉积电荷的突然泄漏；击穿点产生的正离子轰击放电极以及使大量的空间负电荷失效．

Electrical Properties of Precipitated Dust Layer on the Collection Electrode in ESP

The breakdown of precipitated dust layer on the collection electrode will deteriorate the properties of ESP seriously. By means of the theory of the dielectric polarization and gas discharge, the heaping model of precipitated dust layer, forming of surface potential of deposit and the characteristics of voltage and current on the breakdown are investigated. It indicates that the heaping model of precipitated dust layer on the plate has much to do with the current density in which press model is domination. The breakdown of deposit will take place if the surface potential of precipitated dust gets enough great. The broken current increasing sharply through precipitated dust layer depends on the sudden leakage of a great deal of accumulated negative charges on the deposit, positive ions bombing discharge electrode and loss efficacy of a large number of space charges.