Separation performance of fine low-rank coal by vibrated gas-solid fluidized bed for dry coal beneficiation

Vibrational energy was introduced to a dense medium gas-solid fluidized bed to improve the separation performance of 1-6 mm fine low-rank coal. The setup was termed a vibrated gas-solid fluidized bed and could provide a stable fluidization state and uniform density distribution for dry coal beneficiation by the transfer of vibrational energy and the interaction between vibrations and the gas phase. Favorable segregation of the ash content of the 1-6-mm-sized lignite samples is achieved under suitable operating conditions. Higher yields of cleaning coal were acquired when the ash content was reduced. The probable error values were 0.065 and 0.055 at separating densities of 1.68 and 1.75 g/cm(3) for the 1-3- and 3-6-mm-sized lignite samples, respectively. Effective beneficiation of 1-6-mm-sized fine lignite could be achieved using the vibrated gas-solid fluidized bed, which provides an alternative technique for the separation of fine low-rank coal in arid areas. (C) 2015 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.