Carbon deposition behavior of reduction of sinter by carbon monoxide

Carbon-deposition reaction occurs during the reduction of sinter process in the blast furnace, and the carbon-deposition reaction would have negative effect on the BF operation. The CS-8800 type high frequency infrared carbon sulfur analyzer was used to analyze carbon-deposition in the process of sinter reduction, and the reduced sinter microstructure was analyzed by Nova400NanoSEM type field emission scanning electron microscope (SEM). The results show that it is more difficult for the carbon-deposition reaction to occur as the equilibrium concentrations of CO and temperature increases. An amount of carbon precipitates at low temperature, which distributes mainly in the surface and porosity; by contrast, trace amounts of carbon precipitates at high temperature; CO2 in the system significantly inhibits the carbon-deposition; moreover, the amount of carbon deposition increases as the reduction process proceeds.