Condensational Growth of Fine SiO₂ Particles by Magnetized Wetting Agent Tween-20 Solution Vapor

Abstract

The emission of fine particles from coal-fired power plants causing environmental and human health issues is a topic of concern. The enlargement of particles seems to be a promising pretreatment technology for fine particles removal with traditional electrostatic precipitator. The effects of magnetized Tween-20 solution (MTS) by heterogeneous condensation for particle growth were carried out based on the growth tube. The experimental results indicate that the particle growth is more favored by MTS compared with water and nonmagnetized solution. Additionally, the surface tension of magnetized solution is decreased, and the wettability of particles is improved. Furthermore, more effective particle growth is presented at lower mass concentration of MTS. Meanwhile, the initial particle concentration has great influence on the larger size grown particles on magnetized solution. Numerical calculation results demonstrate that the critical supersaturation is lower, but the nucleation rate in the nucleation stage and the growth rate of clusters in the transition stage are both elevated on the condition of magnetized solution. This work reveals that the facilitating process of particle growth by magnetized wetting agent solution is a potential physical and chemical method.

Pilot-Scale Investigation on a Spraying Pretreatment Process Integrated with an Axial Flow Cyclone to Separate Fine Particles with Low Energy Consumption

“…Recently, in terms of the heterogeneous condensation mechanism, Xu et al used an environmental scanning electron microscopy system to directly visualize the heterogeneous condensation process on insoluble particle surfaces and found that the Fletcher theoretical critical supersaturation was higher than that experimentally measured. − Xiong et al proposed a heterogeneous nucleation model based on the Fletcher classical nucleation theory and molecular kinematics theory, considering the effect of surface diffusion mechanism of water vapor molecules, line tension, and roughness . Yin et al, Yu et al, Natale et al, Tammaro et al, and Wang et al conducted several experiments on the heterogeneous condensation of different particles in a growth tube and analyzed the effect of gas or vapor temperature, particle concentration, gas composition, wetting agent, and magnetic field. − Zhang et al discussed the influence of the particle size, chemical composition, and mass fraction of components on the heterogeneous nucleation critical condition based on the classical Köhler theory …”