Dry Beneficiation of High Ash Non-coking Coal Using an Air Dense Medium Fluidized Bed

Abstract

In this project, dry beneficiation of high ash non-coking coal has been conducted by air dense medium fluidized bed. For dry separation, creating and sustaining the air dense medium is a complex process which requires intensive investigation. The dynamic stability of the bed which plays an important role in the sharpness of the separation has also been studied. Based on experimental data, four dimensionless groups i.e. Froude number, Reynolds number, ratio of density of fluid and solid and aspect ratio of the system are used to characterize the stability and quality of fluidization. The above stabilized bed is used to beneficiate coarse coal of -10 +0.1 mm size. The quality of separation is judged by ash analysis of the beneficiated coal samples collected from specified heights of the bed. Enrichment is represented as a function of different operating parameters represented by four dimensionless groups obtained from dimensional analysis approach. The values of enrichment calculated with the developed correlation have been tested which agrees fairly well with the experimental values of enrichment.

Keywords: Air dense medium fluidized bed, dry beneficiation of coal, Dynamic stability of bed, Coal enrichment.