Research on Process Optimization and Parameter Matching of Sedimentation Centrifuge in Coal Slime Dewatering

In view of the problems of low dewatering efficiency of fine grained coal slime, high product moisture content, severe loss of fine particles and others in Xiegou Coal Preparation Plant, based on the mechanism of "particle layered sedimentation-screen mesh collaborative filtration", the horizontal sedimentation filtration centrifuge process is optimized. A collaborative control strategy with coarse particle level content, coarse blending ratio, and feeding concentration as the core is proposed, and a closed-loop process flow of "flotation concentrate+coarse coal slime blending-impurity removal and coarse interception-centrifugal dewatering-dynamic ash content flow separation" is constructed. The industrial verification shows that when the particle size content of >0.25 mm in the feed is ≥ 24%, the concentration is 250 g/L, and the coarse blending ratio is 0.32∶1, the product water content is stably controlled below 18%, which is 4 percentage points lower than traditional scraper discharge centrifuges (product water content is often higher than 22%), and the recovery rate is improved from 85% to 92%. The innovation point proposes a particle size-concentration bivariate control model with a coarse particle size of ≥ 24%, a feeding concentration of 250 g/L, and a coarse blending ratio of 0.32∶1 as the core, to improve the stability and separation efficiency of sedimentary layers and achieve efficient collaborative dewatering of flotation refined coal and coarse coal slime.