多层静电丝网对于亚微米颗粒捕集效果的研究

Research on the trapping effect of multi-layer electrostatic mesh on sub-micron particles

目的:研究多层静电丝网结构对于亚微米颗粒的捕集效果。方法:采用扫描电迁移率颗粒物粒径谱仪(SMPS)采集静电丝网上下游亚微米颗粒,分析其捕集效率和粒径分级效率的影响因素。结果:施加电场后丝网捕集效率显著提高,集尘丝网达到临界层数时效率难以增加;第一层集尘丝网捕集占比高于下游丝网,降低电压下游丝网捕集占比提高;增加丝网层数,最易穿透粒径(MPPS)增大,增强了对超细微米颗粒的捕集,于是捕集了更多的100~1000 nm颗粒。结论:静电丝网对亚微米颗粒的主要捕集机理为静电作用,增加丝网层数增强了扩散作用,高于一定层数时拦截作用和惯性作用也不可忽视。

Aims:This paper aims to study the filtration performance of multilayer electrostatic mesh structures on sub-micron particles.Methods:Downstream sub-micron particles on the electrostatic mesh were collected by scanning electron mobility particle size spectrometer(SMPS);and the influencing factors of their collection efficiency and particle size classification efficiency were analyzed.Results:After the electric field was applied,the collection efficiency of the mesh was significantly improved;and the efficiency was difficult to increase when the dust collection mesh reached the critical number of layers.The first layer of dust collection mesh captured a higher proportion than the downstream mesh;and the voltage was reduced.By increasing the number of screen layers,the most penetrating particle size(MPPS)increased.The capture of ultrafine micron particles was enhanced;and more 100~1000 nm particles were captured.Conclusions:The main mechanism of electrostatic mesh for capturing sub-micron particles is electrostatic effect.Increasing the number of layers of the mesh enhances the diffusion mechanism.When the number of layers is higher than a certain number of layers,the interception and impaction mechanism cannot be ignored.