Numerical simulation of electret magnetic fiber in trapping charged Fe based fine particles

In order to achieve ultra-low emission of Fe based fine particles in the production process of ferrous metallurgy and casting industry, this study proposed a method to improve sub-particle capturing by electret magnetic fibers. Based on CFD-DPM (Discrete Phase Model), the influence of charge distribution on fibers, particle pre-charge electric field intensity, fiber magnetic flux density and particle magnetic susceptibility on electret magnetic fiber capturing property was investigated. The results showed that: around the electret magnetic fiber, the magnetic force was more significantly affected by the distance than did the Coulomb force. The effect of magnetic force was limited within an extremely short distance around the fiber, and there was a linear relationship between the capturing efficiency and charge distribution on fibers and pre-charge electric field intensity. As for 0.5μm particle, the growth rate at which fiber carrying capacity and pre-charge electric field intensity increased the capturing efficiency was lower than that of 2.5μm article. When the particle size was between 0.5 and 1.0μm, enhancing the magnetic flux intensity of electret magnetic fiber and improving particle magnetic susceptibility were less effective in improving the capturing efficiency. When the particle size was between 1.5 and 2.5μm, enhancing the magnetic flux intensity of electret magnetic fiber and improving particle magnetic susceptibility could significantly improve the fiber capturing efficiency. © 2021, Editorial Board of China Environmental Science. All right reserved.