Reduction of FeO in Molten Slags by Solid Carbon in the Electric Arc Furnace Operation

Abstract

the course of operation of 70 l UHP furnace in Chita Plant, Daido Steel, solid carbon has been injected in order to facilitate the reduction of FeO in slag and to improve the energy saving and heating efficiency. In this paper, the effect of the injection method on the reduction rate of FeO in slag is discussed in relation to the quality and size of carbon powder injected, injection rate and nature of molten slag. Moreover the relation between the fundamental data of waste gas and the degree of slag reduction has been comfirmed. The results obtained are summarized as follows:(1) Volatile matter in solid carbon gives a large influence on the reducing reaction. In the coke of higher content of volatile matter, the reduction is controlled by the chemical reaction, while in the coke o f lower content of volatile matter, the reduction is controlled by the transport of FeO in slag.(2) The reduction rate depends on the basicity of molten slag. The reduction rate increases as the basicity of molten slag increases.(3) Estimation of carbon content of molten steel for a rapid operation is found to be possible by the use of the fundamental data of waste gas.