Abstract: A process is provided for the production of titania rich slag from ilmenite. The ilmenite is fed together with carbonaceous reductant, and in the absence of fluxes, to the molten bath of a D.C. arc furnace. The molten bath of the furnace forms the anode and one or more electrodes in the roof of the furnace forms the cathode. A frozen lining is established and maintained between the refractory lining of the furnace and the molten bath and the process includes means to control the thickness of the frozen lining as well as the whole smelting process.

Abstract: A process is provided for the production of titania rich slag from ilmenite. The ilmenite is fed together with carbonaceous reductant, and in the absence of fluxes, to the molten bath of a D.C. arc furnace. The molten bath of the furnace forms the anode and one or more electrodes in the roof of the furnace forms the cathode. A frozen lining is established and maintained between the refractory lining of the furnace and the molten bath and the process includes means to control the thickness of the frozen lining as well as the whole smelting process.

Abstract: The invention provides a furnace having a frozen lining inbetween a furnace lining and a furnace charge, the furnace having means to control the operation of the furnace, including means to measure the temperature in a wall of the furnace adjacent the frozen lining, and to estimate the thickness of the frozen lining as a function of the temperature in the wall, and means to control the rate of heat production in the furnace to urge a thickness of the frozen lining towards a predetermined value. Variables including side wall thermocouple measurements, gas plant instrument measurements, cooling system measurements and electrical, in-feed and chemical composition recordings are monitored, analysed and manipulated. There is also provided means to estimate a future furnace charge composition, perform chemistry control, estimate a material balance of the furnace, and perform inventory control over the furnace.