PROCESS FOR REDUCING ORE FINES AND ARRANGEMENT FOR CARRYING OUT THE PROCESS

摘要

The invention concerns a process for reducing ore fines by means of reducing gas in a fluidized bed process. In order to obtain a homogeneous degree of metallization whilst making optimum use of the reducing gas and minimizing the amount thereof, the following combination of steps is applied: the ore fines (2) are fractionated by means of the reducing gas into at least two fractions each having different grain size distributions; each fraction is reduced in its own fluidized bed (3, 12) with the reducing gas; the reducing gas maintains a first fluidized bed (3) containing the coarse grain fraction and separates therefrom the fine grain fraction, it is then accelerated together with the fine grain fraction and subsequently, as it expands, forms a further fluidized bed (12), the gas being continuously fed from below into the further fluidized bed (12) in a radial symmetrical manner; a secondary reducing gas is introduced directly in a radial symmetrical manner into the further fluidized bed (12); and reduced ore is discharged both from the first and the further fluidized bed (3, 12).