Simulation of coal char gasification using O2/CO2

Abstract

Abstract The authors proposed an integrated gasification fuel cell zero-emission system. The coal char gasification is discussed using high temperature and concentration of CO2 produced by solid oxide fuel cells and oxy-fuel combustion. The gasification is simulated by Aspen plus based on Gibbs free energy minimization method. Gasification model of pulverized coal char is computed and analyzed. Effects of gas flow rate, pressure, preheating temperature, heat losses on syngas composition, reaction temperature, lower heating value and carbon conversion are studied. Results and parameters are determined as following. The optimum O2 flow rate is 20 kg/h. The reaction temperature decreases from 1645 to 1329 °C when the CO2 flow rate increases from 0 to 5 kg/h, the CO2 flow rate should be operated reasonably; lower heating value reduces and reaction temperature increases as the pressure increases; compared to the CO2 preheating, O2 preheating has greater influence on reaction temperature and lower heating value.

Keywords

• Coal char
• Gasification
• Aspen plus