PRODUCTION OF REDUCING GAS

PURPOSE:To stably produce a required amt. of a reducing gas having high reduction potential by using a thermally cracked gas of a hydrocarbon as a reforming gas and regulating the amt. of the oxygen for post combustion to be blown and the amt. of the thermally cracked gas to be fed. CONSTITUTION:Powder and granular iron ore is directly reduced by blowing oxygen into a smelting and reducing furnace from the bottom while supplying said ore into the furnace. Post combustion is executed by blowing oxygen to the surface of the iron bath at this time and the formed gas is fed to a reforming furnace. The thermal cracked gas of the hydrocarbon such as methane is blown to the reforming furnace to reform the gas by which the high-calory reducing gas is obtd. The ratio of the post combustion is changed according to the fluctuation in the output of the molten steel, etc., to maintain the specified amt. of the formed gas at this time. The reduction potential is maintained constant at the value of a high level by adjusting the amt. of the thermally cracked gas to be supplied. The required amt. of reducing gas is stably supplied with high level of reforming reaction efficiency by the above-mentioned method.