The process optimization for separation performance and fluidization stability based on air dense-medium fluidized bed

Abstract

Dry mineral separation methods are based on the pseudo-fluid properties of two-phase gas-solid fluidization during the air dense medium fluidized bed separation. In this paper, the air dense medium fluidized bed separation method was introduced for coal deashing. In order to better understand the impact of separation performance of air dense medium fluidized bed, the uniform stability of fluidized bed on separation performance the factors (fluidization number (N), height-to-diameter ratio (λ) and feeding volume fraction (γ)) were varied. The process optimization of these three factors was investigated. The results showed that the fluidization number was the main factor reflect on fluidized characteristics. The separation efficiency achieved the optimal value when the feeding volume fraction reached 13%. The segregation stabilized at 0.90–0.95, with the possible deviation ranged from 0.10 to 0.15. Further, the yield of cleaned coal is 78.5–80%, and ash content reduced by 75–78%. The dense medium fluidized bed can achieve efficient deashing of coal. Highlights Factors to influence the uniform stability of fluidization within ADMFB. The Process optimization for separation performance was conducted. Synthesizing the separation test results get formulas about feeding volume fraction y and feed rate q. The yield of the cleaned coal is around 80% while its ash decreased to 10%.