Study on Combustion Characteristics and Kinetics of Coal and Semi-Coke Injected by Blast Furnace

The combustion behaviors of semi-coke, anthracite, bituminous coal and their blends were studied using a thermogravimetric analyzer. Compared with anthracite, the experiments showed that semi-coke had low ignition temperature, good comprehensive combustion characteristics and high burnout rate. In compound samples, with the increase of SC1 semi-coke content, the ignition temperature of BC bituminous coal, IC mixed sample and SC1 compound samples gradually decreased, and the comprehensive combustion characteristic index S increased, and the TG curves of the compound samples moved to the low temperature. In the BC and IC compound sample, the ignition temperature and comprehensive combustion characteristic index of compound samples also improved with the addition of SC2 semi-coke and SC3 semi-coke. Furthermore, By means of the universal integral method, the results indicated that the shrinkage cylinder model of phase boundary reaction was the most probable mechanism function of semi-coke, anthracite and bituminous coal combustion. The kinetic parameters of the samples are obtained that the activation energy of semi-coke was lower than that of anthracite. In summary, mixing semi-coke with pulverized coal into blast furnace was beneficial to fuel combustion.