There is a pressing need to replace natural gas in blast-furnace smelting by other fuels. One option is carbon-bearing emulsion (coal dust + fuel oil + water). The temperature in the tuyere zone is calculated, and the change in reductive potential of the tuyere gas and the heat transfer processes in the upper part of the furnace are estimated. The feasibility of replacing natural gas with carbon-bearing emulsion is explored. © 2010 Allerton Press, Inc.