Experimental burnout characteristics of coal gasification fine ash under high temperature conditions and numerical simulation of tangential combustion

Abstract

Developing efficient methods for processing and utilizing coal gasification fine ash (CGFA) is an important issue that urgently needs to be addressed. High temperature combustion can effectively remove unburned carbon and generate secondary ash for further utilization. Through the drop-tube furnace (DTF) combustion CGFA experiment, it can be concluded that the temperature of 1200 ℃ and the residence time of 1.5 s, the carbon content of the furnace outlet fly ash was 0.2 %. Based on the high-temperature combustion characteristics experiment of CGFA, the combustion model of CGFA was verified through the numerical simulation, further exploring the high-temperature tangential combustion behavior of CGFA and bituminous coal. Through numerical simulation research, CGFA was uniformly distributed in the three-layer burners for co-combustion was the optimal operation, and the NOx concentration and fly ash carbon content at the furnace outlet were respectively 218.32 mg/m3 and 98.47 %. The numerical simulation result shows that the co-combustion of CGFA and pulverized coal in power plant was feasible. This article reveals the combustion characteristics and application prospects of CGFA from a new perspective of high-temperature combustion and tangential combustion.