Abstract: In order to solve the problems of complex process flow，high cost of tailings treatment and high risk of core equipment failure in the separation process，the tower mill is used to replace the existing two-stage ball mill to optimize the two-stage grinding and separation process. The results of one-stage grinding test and two-stage elutriation test show that under the condition that the grinding fineness of one�stage magnetic separation concentrate is - 0.075 mm90%，the iron concentrate with total iron grade ≥ 64.50% can be obtained by one-stage tower mill + high efficiency magnetic separation + two-stage elutria⁃ tion process.In the industrial test，through the tests of steel ball installation amount，grinding concentra⁃ tion and optimization of classification process，it is determined that the optimum steel ball installation amount of tower mill is 120 t，the ore discharge concentration is 69.93%，and the ratio of 0.1 mm and 0.075 mm fine screen mesh is 30%∶30%. The grade of iron concentrate is stable at about 64.80%.Com⁃ pared with the original ball mill process，the concentrate grade of the tower mill process increases by 0.05 percentage points，the total tailings grade decreases by 0.20 percentage points，the product overgrinding phenomenon improves，and the metal recovery rate increases by 0.79 percentage points.

Key words: two stage tower mill, two stage elutriation, grade, metal recovery rate