EFFECT OF PRESSURE ON REDUCTION RATE OF IRON ORE WITH HIGH PRESSURE FLUIDIZED BED.

Abstract

The pulverized iron ore has been reduced by H//2 with a batch type fluidized bed reactor of 60 mm I. D. The reduction pressure and temperature are 0. 5 approximately 3. 6 MPa and 973 approximately 1173 K, respectively. On the basis of the experimental results obtained at 973 K, the effects of pressure and gas velocity on the reduction rate have been analyzed according to the bubbling bed model. In the region of the partial reduction between 0% and 70%, the experimental result can be explained well by the present analysis. The analytical results are summarized as follows: When the pressure is increased at a constant gas velocity, the reduction rate increases linearly with the pressure, independently of whether the gas supply determines the over-all rate or not. When the gas velocity is increased at a constant pressure, the increase proportion of the reduction rate decreases with the increase of the gas velocity. When the pressure is increased at a constant moral flow rate, the reduction rate increases exponentially with the pressure, but the increase of the reduction rate saturates as the gas supply approaches the rate determining stage.