Influence of post-combustion heat transfer efficiency on fuel reduction in COREX process

AbstractThe influence of post-combustion, heat transfer efficiency, and the degree of metallisation is studied with regard to coal saving and export gas in the COREX process using a thermochemical model. An increase in post-combustion ratio decreases the coal rate and the amount of reduction gas, which influences the achievable degree of metallisation, when no additional reduction gas is added to the system. Further post-combustion with oxygen generates a higher temperature than that with air at all post-combustion ratios. A higher heat transfer rate is necessary to keep the temperature of the gas within the refractoriness limits of the lining material. It is asserted that the post-combustion ratio, the degree of metallisation, and the medium for post-combustion must be adjusted according to the refractoriness of the lining material of the melter–gasifier, the efficiency of heat transfer mechanisms from the post-combustion zone to the bath, the gas handling efficiency, and the thermal energy requirement o...