Performance of the Szego mill in dry grinding coal and wheat

Abstract

An analysis of the novel Szego mill and its performance in dry grinding of coal and wheat is presented for open-circuit operation. The independent variables were the rotational speed of the mill, feed size and feed rate. Their effects on the dependent variables of product size distribution, power consumption and mean residence time are reported. The higher the mill speed, the shorter the residence time in the mill and the larger the breaking forces. Thus, for easier-to-break materials, like coal, higher feed rates and lower mill speeds, which cause long residence times, produce finer product, while for harder-to-break materials, like wheat, the opposite is true. The feed size was found not to affect the product size distribution.