Experimental study of rotary triboelectric macerals separation for low rank coal

• 1、School of Chemical Enginnering and Technology, China University of Mining and Technology, Xuzhou 221116
• 2、 Key Laboratory of Coal Processing and Efficient Utilization of Ministry of Education, Xuzhou 221116

Abstract：The principle of rotary triboelectrostatic separation were discussed based on dynamics. The equation of dynamics of the tribocharged particles in electric field was established. The low rank coal characteristics of maceral composition, chemical and mineral composition and the triboelectrostatic separation effect were analyzed. The influences of key parameters including charger speed, airflow velocity and separation voltage on the separation effect ofcoal petrographic constituentswere studied.Optimization experiments were designed using Box-Behnken module in Design-Expert software. The results show that when the charger speed is 3014.81r/min, the electric field voltage is 28.89kv and the airflow velocity is 6.56m/s, the effects of low-rank coal rotational friction electricity is the best, and the vitrinite recovery is 69.96%. We can see that on the basis of different electrical properties of low rank coal between vitrinite and inertinite, rotational friction electrostatic separation have great effect on dissociation of coal petrographical constituent. The content of vitrinite increased with the reducing ash content and the content of inertinite decreased with the decreasing of ash.

Keywords： Low-rank coal Rotary triboelectrostatic separation Macerals Optimization