塑料在高压静电分选机中荷电机制及电极参数的计算模拟

Calculation and simulation of charging mechanism and electrode parameters of plastics in high voltage electrostatic separator

为了探究塑料在高压静电分选机中荷电性与电极参数的关系,通过高斯定理和拉普拉斯方程,研究了塑料的主要荷电机制,利用COMSOL Multiphysics中的AC/DC静电模块,结合麦克斯韦方程组,研究了塑料在辊式高压静电分选机中不同参数下的电场强度变化规律,利用MATLAB绘图分析.结果表明:塑料荷电以场致荷电为主,荷电量与颗粒半径、电场强度、塑料相对介电常数成正比;电晕电极配置中,接地辊筒表面电场强度与电压、电晕电极个数成正比,与极距成反比;静电极配置中,电场强度与静电极半径成正比,电场强度作用范围与静电极布置角、静电极形状有关.本文可对塑料高压静电分选的电极参数选用提供参考.

In order to explore the relationship between the chargeability of plastics in high voltage electrostatic separator and electrode parameters,through Gauss theorem and Laplace equation,the main charging mechanism of plastic was studied.Using AC/DC electrostatic module in COMSOL Multiphysics,combined with Maxwell's equations,the change regulation of electric field intensity of plastic at different parameters in roller high-voltage electrostatic separator was studied,and MATLAB was used to draw and analyze.The results show that the charge of plastic is mainly field-induced charge,and the charge is proportional to the particle radius,electric field strength and relative dielectric constant of plastic.In the corona electrode configuration,the surface electric field intensity of the grounding roller is proportional to the voltage and the number of corona electrodes,and is inversely proportional to the polar distance.In the electrostatic pole configuration,the electric field strength is proportional to the radius of the electrostatic pole,and the range of the electric field strength is related to the arrangement angle of the electrostatic pole and the shape of the electrostatic pole.This paper can provide reference for the selection of electrode parameters when conducting high-voltage electrostatic sorting on plastics.