Separation Properties of Magnesite Particles in the Trapezoidal High Voltage Electric Field

This paper proposed a trapezoidal high voltage collecting electric field to study the separation characteristics of Magnesite particles from the mixture of SiO 2 and MgCO 3 , which was charged by the negative corona discharge. The mathematical model of particle motion was established to simulate the separation process of magnesite particles based on the analysis of the force on charged particles. The advantages of the trapezoidal electric field were experimentally verified, and the separation efficiency of magnesite particles was investigated at different angles and voltage levels of the electrode plates. Results show that pulsed plasma corona discharge could improve the ability of MgCO 3 particles to accept a charge and the charge-to-mass ratio increase from −2.179 nC/g to −7.232 nC/g. Furthermore, if the charge-to-mass ratio exceeds −10 nC/g, the charged MgCO 3 particles will collide with the electrode plate, and the separation efficiency will decrease. If the charge-to-mass ratio is less than −2.5 nC/g, the deflection of the charged MgCO 3 particles is not apparent, which also reduces the separation efficiency. At the same voltage applied on the electrode plates, the optimum angle of the electrode plate is 5 degrees. At an angle of 5 degrees and a voltage of −20kV, the separation efficiency achieves 83%.