Separation lower limit in a magnetically gas–solid two-phase fluidized bed

The magnetically stabilized fluidized bed has the characteristics of a dispersion gas–solid two-phase flow. The essential condition by which the feedstock was separated by bed density was determined through studying the composition and action of dense medium (gas–solid fluidized bed) on feedstock. The forces exerted on a separated feed with sizes close to the lower limit of separation were analyzed. The correlative formula of the lower limit of separation was obtained theoretically. Experimental results in a 100-mm magnetically fluidized bed model show that the coal can be separated efficiently under a good fluidization state with Ep values of 0.05–0.08. The lower limit of separation is about 0.5 mm.