MOLTEN STEEL MANUFACTURING DEVICE

摘要

PURPOSE: A molten steel manufacturing device is provided which manufactures the molten steel by using charcoal and pellet/lump ore. CONSTITUTION: The device comprises: (i) a melting gasifying furnace(110) which melts preliminary ore to be reduced by burning and gasifying general charcoal and generates high reduced gas; (ii) a pre-reducing furnace(120) which pre-reduces pellet/lump ore and supplies them to the melting gasifying furnace(110); (iii) a high-temperature cyclone(130) which collects dust in auto exhaust and supplies the dust-eliminated reduced gas to the pre-reducing furnace(120); (iv) a dust burner(140) which supplies the collected dust at the high temperature cyclone(130) to the melting gasifying furnace(110); (v) a first dust collecting device(151) which collects a portion of reduced dust discharged from the high temperature cyclone(130) and cools down of it; (vi) a cooled gas circulating line(150) comprising a booster(152) and a temperature control valve(153); (vii) a pre-reduced auto exhaust discharge line(170) comprising a second auto exhaust discharge pipe, a second dust collecting device, a second cooled gas discharge pipe and a pre-reduced gas flow amount controlling valve; and (viii) a pressure controlling line(160) comprising a pressure-controlling gas discharge pipe(162) and a pressure-controlling valve(161). The device further comprises: (i) a gas modification device(180) which is positioned between the melting gasifying furnace(110) and the high temperature cyclone(130) and modifies CO2 gas component in the high temperature reduced gas from the first auto exhaust supplying pipe(111); (ii) a cooled gas circulating pipe(190), one end of which is connected to a second cooled gas discharge pipe and the other end of which is connected to a first cooled gas discharge pipe(155), wherein the gas modification device(180) comprises a carbon-containing material supply pipe(181), a modified gas discharge pipe(182) and a modified material discharge pipe(183) and the cooled gas circulating pipe(190) has a second open and close valve(191).