10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Correlation Between Corona Current Distribution and Collection of Sulfuric Acid Aerosol in a Wet Electrostatic Precipitator
YIFAN WANG, Chenghang Zheng, Xuefeng Zhang, Zhengda Yang, Yi Wang, Dawei Duan, Xiang Gao, Zhejiang University
Abstract Number: 747 Working Group: Control and Mitigation
Abstract The emission standard have become increasingly stringent in recent years as more attention has been given to the sulfuric acid aerosols. Wet electrostatic precipitator (WESP) is typically used to remove sulfuric acid aerosols. However, removing sulfuric acid aerosols with small size and high concentration were less efficient.
Enhancing the electric field intensity and optimizing distribution characteristics of the electric field are the key to improve the collection efficiency of the WESP. However, the current researches mainly focused on the influence of discharge electrode geometry on V-I characteristic. Few researches have been done on the detail current density distribution which comprehensibly reflects electric field.
In this study, detailed current density distribution on the collecting plate were researched. An experimental WESP which the current density of measuring point can be obtained automatically was designed. Twenty-three kinds of discharge electrodes with different needle shape, length, and spacing were used as the experimental discharge electrode. Firstly, V-I characteristic of the experimental discharge electrode were measured. Then, we investigated the circumferential and axial current density distribution using current measuring device. And fractional discharge electrode were tested in sulfuric acid aerosols.
The results show that the effect of sulfuric acid aerosols space charge is significant and causes corona current decrease sharply at high concentration. Reducing the current density at the entrance by 87% in 53.6 mg/m3 sulfuric acid aerosols. Increasing the needle length and decreasing the spacing of needles can provide higher corona current density. Interestingly, the rotating of discharge electrode almost makes no differences to the V-I characteristic, but the current density distribution changes significantly. The current distribution becomes more uniform and improves the removal performance. Rotating 30° relative to the vertical surface is the best choice under the experiment condition. And we will develop a numerical modeling to verify the effects for the corona current and collection efficiency in barbed electrode.