Particle classification characteristics of the particle classifier of decoupled dual loop reaction system

Abstract

A particle classifier consisting of a cyclone separator and a settling separator for a decoupled dual loop reaction (DDLR) system has been designed. The classifier is expected to separate the circulating bed materials into two functionalized groups of different particle sizes and/or densities and allocate them into the pyrolysis/gasification loop and the upgrading/reforming loop of the DDLR system individually, so that the reactions in the dual loops could independently occur under optimized thermodynamic and kinetic conditions. To this purpose, the flow field and particle classification performance of the classifier have been investigated by means of numerical simulation and cold experiment with quartz sand and/or coal of different particle sizes as feedstock and air as driving gas. The simulation results show that the cyclone separation and the settling separation are interactive and their contributions to the flow field could be regulated individually to realize an efficient classification of mixed particles with adjustable cut-size. The experiments show that the settling separation takes major role in the classification performance, which is determined by the particle terminal velocity. The mixture of binary particle groups with different particle sizes and/or densities could be quickly and efficiently separated with a Newton efficiency up to 98%.