Experimental Study on the Electrostatic Precipitability for the High-Alumina Fly Ash of Burning ZHUNGEER Coal in China

Electrostatic precipitators (ESP) are widely used in coal fired power plants for control of particulate. In recent years, the efficiency of ESP has obviously decreased when the power plant burned the high-alumina coal, especially in western China, and it is difficult to reach the emission standard. In order to find the reason that the high-alumina fly ash influences the efficiency of ESP, the fly ash in entrance and exit of ESP has been sampled. By analyzing their chemical composition, resistivity and adhesive force, using the dust electrical resistivity test instrument and adhesive force test apparatus invented by self-independence, and testing the current-voltage curve of the fly ash under operating the ESP. The results show when the content of AI₂O₃ in the fly ash in entrance and exit of ESP is 44.2% and 47.8%, the resistivity of fly ash is over 10¹² Omegaldrcm, but it doesn´t cause the obvious reverse corona. The adhesive force of the high- alumina fly ash is very little, and the fly ash is sensitive to the smoke speed in electric field, dust re-entrainment is easy to produce, so the efficiency of EPS decreases.