Removal of sulfuric acid aerosol in a wet electrostatic precipitator with single terylene or polypropylene collection electrodes

摘要

Wet electrostatic precipitators (ESPs) are good options for effective control of sulfuric acid aerosol emission. However, various problems caused by materials and non-uniform distribution of water film limited the applicability of typical wet ESPs. Research on ESP technology has tried to find more suitable and anti-corrosive methods to solve these imperfections. This research was inspired by the requirement to replace rigid collection electrode by single terylene or polypropylene fabrics. A patented system was designed, and the capillary difference between terylene and polypropylene fabrics was illustrated. Contrastiye V-I curves of different collection electrodes were investigated under same conditions. The effects of several important parameters on the removal of sulfuric acid aerosol were analyzed. The results demonstrated that the variations of absorbed mass were significantly influenced by physical properties of the liquids and the structure of fabrics. The behavior of the new ESP was consistent with the typical ESP using a thimbleful of water penetrating terylene or polypropylene collection electrode via capillary flow. The collection efficiencies by terylene and polypropylene fabrics were higher than those by fiberglass reinforced plastics (FRP) under certain conditions. The collection efficiency had linear relationship with specific surface area (SCA) and mass concentration. The collection efficiency increased with increasing electric field strength, average diameter of particles and with decreasing gas temperature. As long as there was any water on the collector surface, any particle would exhibit similar collection efficiencies, whether of high resistivity or not. Experimental and theoretical investigations indicated that single terylene or polypropylene collection electrode had significant advancement which could improve wet ESP applications, such as superior performance and continuous operation ability compared with typical materials.