Method for producing molten iron

A method for producing molten iron in a melting process having a tapping process, comprising 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,
• (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, wherein
• the top-blowing lance comprises an injection port at a lower end part thereof, and a height position of the lower end of the top-blowing lance is controlled so as to follow changes in a height position of a top surface of the melt with tapping time, which are calculated from a premeasured relationship between an internal shape of the furnace and a change in the discharged amount of molten iron and slag with time.