PURPOSE: To efficiently obtain pig iron and recovered gas from low cost materials, by combining a melting-gasifying furnace for melting reduced iron while forming reducing gas with a rotary-kiln reducing oven for converting powdery iron ore into reduced one with the reducing gas.
CONSTITUTION: Low-grade powdery iron ore 14, etc. and a carbonaceous reducing agent 15 such as coal are charged in a rotary-kiln reducing oven 20 through an opening 21 for charging iron ore. Granular reduced iron 7 obtd. by reducing the iron ore with heat using reducing gas 12a is charged from an opening 22 for quarrying out reduced iron through a supply line 23 in a melting-gasifying furnace 1. Coke 8 and auxiliary materials 13 such as a slag-forming agent are charged together with them through a charging opening 2. In addition, oxygen 9, fuel 10 such as fine carbon powder, auxiliary materials 13a such as a slag- forming agent and steam 11, if necessary, are supplied to the vertical melting- gasifying furnace 1 through tuyeres 4. In the furnace 1, a reduced iron-packed layer (a), a coke-packed layer (b), a combustion chamber (e), molten slag (c), a basin (d), etc. are formed. Reducing gas 12, molten pig iron and molten slag are withdrawn from it through a gas-withdrawing opening 3, a tap hole 5 and a cinder notch 6, respectively.
HATANO MICHIHARU
MIYAZAKI TOMIO
SHIMODA TERUHISA
OKI KOUJI
