Patent ID: 6187076
Filing Date: 2001-02-13
Classification: C21B

Abstract:
A fluidized bed reduction method comprising the steps of:supplying reducing gas into a plurality of chambers connected with one another in a series through a plurality of supply lines connected with the plurality of chambers, respectively, each chamber being supplied with reducing gas through the corresponding supply line at a predetermined supply rate;introducing powder raw material into a first chamber of the plurality of chambers to produce a fluidized bed of powder raw material in the first chamber owing to the supplied reducing gas;allowing powder raw material to move from the first chamber to the subsequent chambers while producing a fluidized bed of powder raw material in each subsequent chamber, the powder raw material being moved from one chamber to next chamber at a position lower than a top of the fluidized bed formed in each chamber;controlling the supply amount of reducing gas to each chamber in accordance with a reducing state of the powder raw material in each chamber; anddischarging reduced material from at least one chamber of the plurality of chambers.