Enhancement of hybrid combustion of semi-coke and bituminous coal by rare earth oxides

Abstract

ABSTRACT The use of semi-coke instead of anthracite coal for blast furnace injection to reduce ironmaking costs is becoming increasingly popular. To optimise the usage of semi-coke, it is essential to investigate the mixed combustion of semi-coke and bituminous coal. Within this study pulverised coal combustion was analysed using a thermogravimetric analyser. The results showed that the proportion of semi-coke in the mixed pulverised coal did not exceed 30%. However, 1 wt-% La2O3 as a catalyst increased the proportion of semi-coke by 15%. In addition, the kinetics of combustion of pulverised coal was investigated using the Flynn Wall Ozawa method and the catalyst reduced the activation energy of the reaction. The average activation energy decreased from 84.24 KJ/mol to 74.59 KJ/mol, especially at a conversion of 0.4, with a maximum reduction of 17.3%. Overall, La2O3 is an effective catalyst to increase the utilisation of semi-coke for practical industrial applications.