Investigating the Effect of Different Discharge Electrode Geometries on the Performance of Spiked Electrode-Plate Electrostatic Precipitator

Since the early twentieth century, electrostatic precipitators have been recognized as an important industrial technology and have been used as air pollution control devices in industrial applications such as cement plants and diesel engine generators. Despite the high overall efficiency of electrostatic precipitators, the fractional efficiencies for submicron particles are lower than that of larger particles. On the other hand, the laws on particulate matter injected into the ambient air by industrial processes have become increasingly stringent (for example, a 30 percent reduction in the amount of particulate matter emitted by Chinese thermal power plants from 2012 to 2014). Therefore, the need to take precautions to improve the performance of this equipment in the face of these particles is felt more than ever. In this paper, by presenting formulations related to various processes within electrostatic precipitators and their three-dimensional numerical modeling, the electrical and electrohydrodynamic properties as well as, the submicron particle collection efficiencies for a precipitator in laboratory dimensions with different spiked electrodes are investigated. For this purpose, airflow lines and particle collection efficiencies with a diameter of 0.25 to 1.5 μm for bidirectional and unidirectional spiked electrodes have been evaluated and compared. The results indicate that for particles with diameters of 0.25 to 1.5 μm, the two-side spiked electrode is the best discharge electrode arrangement for collecting submicron particles. The effect of particle mass flow rate on the deposition efficiency of fine particles for a two-side spiked electrode has also been investigated. The simulations show that the particle deposition efficiency decreases with increasing particle mass flow rate at the inlet.