A novel water film enhanced electrostatic agglomeration process to remove fine particles: performance and mechanism

Abstract

Wet electrostatic agglomeration (WEA) is a very promising method in fine particle removal, however, it is still a challenging problem to avoid short-circuiting of the equipment caused by spraying water during traditional WEA. In this work, a novel WEA process based on a water film was established for the first time, and the fine particle removal and process mechanism were investigated. The influence of discharge and ground electrodes on the particle agglomeration performance was studied, indicating that a much better agglomeration performance was obtained by the spike plate (discharge electrode) thanks to the stronger electric field covering the entire agglomeration area. The corrosion-resistant and low-priced polyvinyl chloride (PVC) plate could significantly improve the water distribution effect after surface grooving modification, and its agglomeration as a grounding electrode under wet conditions was comparable to that of the wet metal plate. The mechanism of the water film enhanced WEA process lay in the fact that the high-voltage electric field greatly promotes the evaporation of the water film, which increased the humidity in the agglomeration space, resulting in liquid bridge force between the water-absorbing particles. In summary, this work provides an alternative novel idea for enhancing the agglomeration performance of the traditional WEA process.