The Influence of Flow Distribution on the Performance Improvement of Electrostatic Precipitator

Particulate matter emission is one of the major air pollution problems of coal fired power plants. Though fine particles constitute a smaller fraction by weight of the total suspended particle matter in typical particle emissions, they are considered potentially hazardous to health because of their high probability of deposition in deeper parts of the respiratory tract. Electrostatic precipitators (ESP) are the most common, effective and reliable particulate control devices which can handle large gas volumes with a wide range of inlet temperatures, pressures, dust volumes and acid gas conditions. Though the electrostatic precipitators are generally running at the collection efficiency as high as 99.95%, the anticipated regulations on particulate matters of 2.5 microns (PM2.5) have led the local power station to explore improvement options to further control the emissions of the fine particulate at a minimum cost even its current particulates emissions are well under the limits of its current environmental license. The performance of Electrostatic Precipitator (ESP) is significantly affected by its complex flow distribution. In this study the gas flow through the ESP at a local power station is modelled numerically using computational fluid dynamics (CFD) code Fluent to give insight to the flow behavior inside the ESP. The flow simulation was performed using the Realizable k-e model. The results of the simulation are discussed and compared with on-site measured data supplied by the power plant.