Study on the Electrostatic Concentration of Low Ash Coal in Corona Discharge Field

Abstract

In order to recover the coal concentrates of low ash and iron content, the electrostatic separation of coal in the corona discharge field was investigated by a Huff type separator. From the experiments of the coal separation in the corona discharge field, it is recognized that the coal particles which are extremely low in ash and iron content are attracted to the grounded roller, while the particles of high ash content are repelled from the roller. It is more successful in the corona discharge field to recover the coal concentrates of low ash and low iron content than in the field without corona discharge. Furthermore, from the measurement of conductivity of coal and the electric charge of coal particles acquired in an electric field, the relation among conductivity, ash content, and iron content of coal was clarified, and then the mechanism of coal separation in the corona discharge field was considered.