MULTISTEP FLUIDISED-BED PRELIMINARY REDUCING APPARATUS FOR IRON ORE AND METHOD THEREFOR

摘要

PURPOSE: A two-stage fluidized bed prereduction line of iron ore powder and a method thereof are provided not only to improve the distribution efficiency but also to restrain flying of medium and fine particulate iron ore by forming first fluidized bed reduction furnace in such a structure that the lower part of the first fluidized bed reduction furnace is wide while the upper part thereof is narrower, and second fluidized bed reduction furnace in such a structure that the upper part of the second fluidized bed reduction furnace is wide while the lower part thereof is narrower. CONSTITUTION: The two-stage fluidized bed prereduction line of iron ore powder comprises a first fluidized bed reduction furnace (20) in which medium and fine particulate ore are scattered and discharged through the upper part thereof, and large particulate ore is reduced as forming a bubbling fluidized bed after iron ore powder is supplied from a hopper (10) for storing the iron ore powder; a second fluidized bed reduction furnace (30) in which medium and fine particulate ore are reduced as forming a turbulence fluidized bed after receiving the medium and fine particulate ore scattered and discharged through the upper part of the first fluidized bed reduction furnace (20); and a first high temperature cyclone (40) collecting fine particulate ore contained in the exhaust gas of the second fluidized bed reduction furnace (30).