The Countercurrent Reduction of Iron Ore in a Fluidized Rotary Bed

Abstract

In a rotary furnace, an are bed was fluidized when the centrifugal force acting on are particles was equal to the force of gravity. In this bed, all cross-sectional area inside the tube was covered with moving are particles. Therefore contact of gas with are particles was improved as a conventional fluidized bed. Ore particles could be reduced in a countercurrent gas flow by inclining the rotary tube.
Small sized hematite, magnetite and sintered are were reduced in the countercurrent fluidized bed. The results were as follows;
1) The tendency of are sintering was lessened by using a reducing tube of larger diameter.
2) Effect of gas film on the reduction was small.
3) Under the condition of the same quantity of are in fluidizing zone, the utilization coefficient was constant whether the diameter of reducing tube was large or not.
4) The calculation values of reduction were in good agreement with the experimental values.
5) As the are size was smaller, the reducing rate per unit inner volume became larger.