BEHAVIOR OF PARTICLE FLOW DYNAMICS IN MODEL APPARATUS OF PILOT SCALE SWIRLING ENTRAINED BED

The effect of momentum on the residence time of particles with downward swirling was studied in model apparatus of a pilot-scale swirling entrained bed. In a single-chamber gasification furnace in which pulverized coal is both gasified and combusted, the efficiency of gasification is dominated by the particle residence time and the region occupied by the particles. The length and the residence time increased with decrease of the furnace exit diameter and of the rotational diameter at lower burners, with increase of the velocity at upper burners, and with increase of the flow rate at upper burners. The effects on particle residence time were made clear using a momentum parameter α, which was determined as a function of the velocity, the flow rate, and the rotational diameter of lower and upper burners. The length of downward swirl can be derived from α, and its relation to the residence time was obtained. © 1990, The Society of Chemical Engineers, Japan. All rights reserved.