Study on Improving the Performance of Electrostatic Precipitator in the Large-scale Semi-dry Flue Gas Desulfurization System

摘要

Dedusting unit is necessary in the circulating fluidized bed flue gas desulfurization (CFB-FGD) system, a semi-dry FGD technique which is widely used in air pollution control projects. The dedusting unit is located after the FGD absorber, to collect the desulfurization absorbent for recycle, and also to ensure to satisfy the dust emission standards. Electrostatic precipitator (ESP) is most popularly used in large-scale semi-dry FGD system. But the ESP operating conditions in FGD system are much different from those in general use, with high dust concentration, high humidity and high specific resistivity. According to the ESP operating cases in the semi-dry FGD projects, the effect factors on ESP performance are studied in this paper, such as dust specific resistivity, dust concentration, gas humidity, dust cleaning mode and power supply. The measures to improve the collection performance are also studied in this paper, from the stage of design, installation and operation.