FLUIDIZED-BED REDUCING METHOD FOR CHROMIUM ORE OR THE LIKE

PURPOSE:To reduce the consumption of coal, by adding char and coal to the chromium ore, etc., preheated with the use of char, reducing the ore in a fluidized bed, and separating the reduced ore and the char at high temp. to effectively utilize the heat retained by the char. CONSTITUTION:Powdered chromium ore and high-temp. char are charged into a preheating furnace 1, oxygen or air and the high-temp. exhaust gas from a reducing furnace 2 are further supplied to burn the combustible components, and the chromium ore is preheated. The preheated ore is charged into the fluidized-bed reducing furnace 2 along with char, a requisite amt. of coal is further supplied, a fluidized bed is formed by the reducing gas heated to a high temp. by a preheater 12, and the ore is reduced. The exhaust gas from the bed is supplied to the preheating furnace 1, and the reduced ore and char are separated at the high temp. in a separator 6. The obtained reduced ore having a low content of char is supplied to a melting and reducing furnace, the char is supplied to the preheating furnace 1 as fuel, and a part of the char is used in the fluidized-bed reducing furnace 2 as the replenishment for coal.