FLOW-TYPE PRE-REDUCTION APPARATUS OF POWDER IRON ORE AND PRE-REDUCING METHOD WITH THE SAME

摘要

PURPOSE: A pre-reducing method of powder iron ore is provided to improve reduction and gas-using rate by pre-reducing powder iron ore depending on particle size and to minimize the amount of dispersed powder iron ore. CONSTITUTION: Corpuscular iron ore is dispersed together with exhaust gas, and middle/large iron ore is introduced into a first gas feed pipe(126) from a first flow layer path(110). After that, the middle/large iron ore is reduced primarily as forming a vapor flow layer with reduction gas passing a first gas dispersing plate(112). The middle/large iron ore is charged into the intermediate portion of a second flow layer path(120) and reduced secondarily. The corpuscular iron ore is dispersed together with exhaust gas from the second flow layer path. The corpuscular iron ore is separates from gas in first and second cyclones(114,124) and charged into a third flow layer path(130). The corpuscular iron ore is secondarily reduced, separated from gas and circulates in the third path. The reduction iron of the second/third paths is finally discharged through second and third discharge pipes(121,131) respectively.