PURPOSE: To let reduced iron production reaction be perfectly accomplished by controlling the emperatures of the floating layer reaction furnaces of respective stages independently, furnace by furnace, in the reduced iron producer of multistage floating layer type.
CONSTITUTION: A preheater 1, pre-reducing furnace 4, separator 6 are disposed in series and oxidative gas 13 is introduced to the respective stages 1, 3, 4 other than the separator 6. Iron ore powder 2 is charged into the preheater 1 and the gas 10 having been boosted by a blower 12 is put in the reducing furnace 4. In the reducing furnace 4, the floating layers are formed by the charged powder coal 5 and the pre- reduced iron ore powder from the pre-reducing furnace 3 and the iron ore is reduced to reduced iron, which is then separated and recovered in the separator 6. The gas of the reducing furnace 4 pre-reduces the preheated ore from the preheater 1 in the pre-reducing furnace 3. These reductions are accomplished by the CO, H2, CH4, coke formed through carbonization of the coal 5 of the reducing furnace 4. In the floating layer stages 1, 3, 4, the temperatures are always measured with thermometers 15 and when they lower, the oxidative gas 13 is introduced to burn part of the abovementioned CO, H2, etc. and raise temperature, thereby accelerating the reaction.
ISHINO KAZUYUKI
HORIE TETSUO
Next Patent: PHOSPHORUS-COPPER TYPE BRAZING ALLOY AND MANUFACTURE THEREOF