Patent ID: 8475561
Filing Date: 2013-07-02
Classification: C21C

Abstract:
1. A method for producing molten iron in a melting process having a tapping process, by melting an iron source material with an iron bath melting furnace comprising a top-blowing lance at an upper part of the furnace, a bottom-blowing tuyere in the bottom of the furnace and a tap hole at a lower part on a side of the furnace, the method comprising: (A) charging the iron source material, a carbonaceous material, and a flux, into the furnace and top-blowing an oxygen-comprising gas through the top-blowing lance while blowing an inert gas through the bottom-blowing tuyere into a melt present in the furnace to stir the melt to thereby melt the iron source material and generate the molten iron and slag with combustion heat from combusting carbon in the carbonaceous material and/or in the molten iron to form a carbonaceous material suspending slag layer, in which part of the carbonaceous material is suspended, on the top layer portion of the slag, and to form a carbonaceous material coating layer, comprising only the carbonaceous material, on the carbonaceous material suspending slag layer, (B) discharging the molten iron and the slag through the tap hole while holding a position of the furnace in generating the molten iron, and (C) continuing or interrupting generation of the molten iron and continuing top-blowing of the oxygen-comprising gas to thereby keep a temperature of the molten iron in the furnace at or above a pre-set lowest temperature of the molten iron.