COMBUSTION BEHAVIOR OF PULVERIZED COAL PARTICLES IN A HIGH-TEMPERATURE AND HIGH OXYGEN CONCENTRATION ATMOSPHERE

The combustion of pulverized coal particles in a high temperature and high oxygen concentration atmosphere was studied experimentally using a laminar flow furnace. Some peculiar phenomena were observed during the early stages of coal particle combustion. It was shown that particle rotation occurred in the devolatilization region and rotation frequency reached 3000-5000 cycles s-1. Also, thermal cracking occurred during devolatilization. These findings suggest that these phenomena were induced by the evolution of volatile matter, and that char combustion occurred simultaneously in the devolatilization region under a high temperature and high oxygen concentration atmosphere. A model to explain the mechanism of char ignition during devolatilization is presented.