Abstract: Considering the situation that the natural quality resources are gradually decreasing but the demand is increasing year by year,this paper presents an industrialized beneficiation method for diatomaceous earths which is based on the size difference between the diatom and the impure minerals,the coarse class of the scoured diatomite ore slurry is wiped out by sieving,the rest slurry is purified by the centrifugal separator.The effects of the cone angle,drum speed,feed concentration,feed flow rate and feed time on the diatomite beneficiation are investigated,and the correlation of these factors is analyzed through the Response Surface Experiment design to further optimize the working conditions of the centrifugal separator.The results show that the feed flow rate has much influencing on the SiO₂ content in the diatomite concentrate and the tailings concentration,and that the SiO₂ content in the diatomite concentrate is 87.5%,the tailings concentration is 6.98% when the cone angle is 0.5°,the drum speed is 856r/min,the feed concentration is 24.66%,the feed flow rate is 14 L/min and the feed time is 90seconds.The continuous pilot-scale experiment with the optimal combination above has the results that the SiO₂ content in the diatomite concentrate is 87.61%and the tailings concentration is 6.14%.The SEM picture of the diatomite concentrate shows he blocked pores with some deposited impurities are mostly cleaned.And the analysis with the JX-2000image analyzer indicates the change of diatom damage rate is below 5%after the diatomite ore is processed by the pilot-scale experiment line.The research achievements provide the theoretical guidance for the design,production and machine operation of the diatomite preparation plant.