Patent · US Expired

Process for reducing ore fines and arrangement for carrying out the process

US6030432A · kind A · utility

5Cited by
5References
13Claims
0Family size

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Key dates

Filing dateNov 17, 1997
Grant dateFeb 29, 2000
Priority date
Expiry dateNov 17, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/134
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

In a process for the reduction of fine ore by reducing gas in the fluidized bed method, the following characteristic features are realized in order to achieve a uniform and even degree of metallization at optimum utilization of the reducing gas and while minimizing the amount of reducing gas employed, that the fine ore is fractionated by aid of the reducing gas into at least two fractions having different grain size distributions, that each fraction is reduced by the reducing gas in a separate fluidized bed, wherein the reducing gas maintains a first fluidized bed containing the coarse-grain fraction and separates the fine-grain fraction from the same, is accelerated together with the fine-grain fraction, subsequently under pressure release forms a further fluidized bed, into which it is continuously injected in a radially symmetrical manner and from below, and wherein, furthermore, secondary reducing gas additionally is directly injected into the further fluidized bed in a radially symmetrical manner, and that reduced ore is discharged from both the first and the second fluidized beds.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.