Abstract: In order to further realize the energy saving and consumption reduction of an iron ore grinding process,taking the high pressure roller grinding and preselected concentrate of an iron ore as the research object and the grinding power consumption as the evaluation index,orthogonal test method was used to optimize the grinding parameters of tower mill on the basis of single factor test. The results showed that:① The optimum grinding concentration was 60%,the rotating speed of spiral stirrer was 300 r / min,the medium filling rate was 16. 15%,the medium ratio (ϕ8 mm steel ball mass ratio) was 50%,and the ratio of material to ball was 0. 166 4. ② The orthogonal test determined that the appropriate grinding concentration was 60%,the spiral stirrer speed was 360 r / min,the medium filling rate was 20. 77%,the medium ratio (ϕ8 mm steel ball mass ratio) was 100% and the feed ball ratio was 0. 16. ③ The utilization coefficient of -0. 074 mm mill in orthogonal test is 44. 32% higher than that in single factor test,and the grinding power consumption is 9. 68% lower than that in single factor test. ④ The influence of the five factors of tower mill on grinding power consumption from large to small is the grinding concentration,spiral agitator speed,feed to ball ratio,medium filling rate and medium ratio. Orthogonal test optimization further reduces the grinding power consumption of tower mill,and the particle size distribution of grinding products is more uniform,which is conducive to improving the subsequent sorting effect.

Key words: tower mill,orthogonal test,grinding power consumption,mill utilization factor