Abstract: In the process of operation of the vertical-spindle pulverizer, repeated grinding of circulating material from air classifier may cause reduction of treating capacity of pulverizer, increase of power consumption and wearing of equipment.Furthermore, combustion in boiler of enriched mineral matters in pulverized coal gives rise to more presence of air-polluting contaminants.In order to bring to light the law governing cumulation and migration of minerals at different nodes in mill, and hence find out basic processes for both online and offline removal of such minerals, cyclic milling test is conducted in an indigenous roller mill with high-sulfur and lignite coal samples, with an aim to explore the size distribution and variation of ash and mineral contents of puluverized coal and circulating load, and reveal the law of accumulation and migration of minerals in pulverizer.