Effect of CO2-O2 oxidizing atmospheres on the combustion characteristics of metallurgical coke and anthracite

Abstract

As a novel method for blast furnace ironmaking, CO2 is utilized in the hot blast and the pulverized coal carrier gas. In order to clarify the function mechanism of CO2/O2 oxidizing atmospheres on the metallurgical reaction of metallurgical coke and anthracite, the combustion characteristics of anthracite and coke in CO2/O2 atmosphere were obtained by non-isothermal thermogravimetry. The physical and chemical structural characteristics of anthracite and coke were measured systematically by using X-ray diffraction(XRD), X-ray fluorescence spectrometer (XRF), laser particle size analysis, scanning electron microscopy(SEM) and Raman spectroscopy analysis. The results show that when the proportion of CO2 in the reaction gas increases, the ignition performance and comprehensive combustion performance of anthracite and coke decrease, and higher heating rate is not conducive to the reaction. The ignition performance and the comprehensive combustion performance of the samples rank in the order anthracite > coke. The volume model (VM) and unreacted core model(URCM) were used to fit the experimental data, and the reaction kinetic parameters and combustion reaction mechanism were obtained. The performance of VM model is slightly better than URCM model.