Abstract: The stirring mill has the characteristics of low energy consumption and high efficiency,and is expected to replace the traditional ball mill as the main equipment for iron ore fine grinding.In order to fully understand the influence of the grinding process parameters of the stirring mill on the particle size characteristics of the grinding products,the vertical spiral agitating mill machine is adopted for grinding tests of Gongchangling Concentrate regrinding feeding.The accumulation particle size and particle size distribution characteristics of grinding productions were detected through NKT6100-D laser particle size analyzer,and R—R granularity characteristic equation was applied for analyzing product granularity,so as to systematacially study the effect law of grinding process parameters on product size characteristics.The results showed that: under the conditions of medium ratio m（φ5 mm）∶m（φ3 mm）=2∶3,pulp concentration of 65%,feed to ball ratio of 0.6,filling rate of 70%,agitator speed of 450 r/min,the particle size of the products is fine and relatively uniform,in which the -0.043 mm particle content,the uniformity coefficient n and particle characteristic parameter b is 92.23%,1.177 7 and 0.031 4,respectivly.The research results have certain guiding significance for improving the qualified grain yield of grinding products.

Key words: stirred mill,grinding products,characteristic of particle size,particle size distribution