PURPOSE: To easily obtain a high-purity iron powder material at a low cost by dividing a converter gas equally to two systems according to the concn. of the oxygen contained therein so that converter dust can be recovered in a nonoxidative state.
CONSTITUTION: The oxygen concn. in the converter gas is measured by a oxygen concn. meter C provided to a gas guide path 2 and the dust removal and recovery are executed by a dust collector 3 of a dust-non-recovering system A through a selector valve 6 during the time when the measured concn. is a specified value or above (initial period an end period of blowing). The converter gas is then introduced to a dry dust recovering device 9 of a dust recovering system B through a selector valve 7 when the oxygen concn. of the gas decreases to the specified value or below. The converter gas is then subjected to the dust removal with a heat-resistant filter 10 by which converter dust is collected. The recovered converter dust is fed out of a primary feeding valve 11 into a purging chamber 21 where gaseous nitrogen is fed from a purging gas supply system 15 to purge the gaseous CO2 in the chamber 12. The dust is adequately fed from a dust feed system 14 as the high-purity iron material in the nonoxidative atmosphere. The iron powder having about ≥80% purity is thud obtd.
MARUKAWA YUJO
TATENO MASAKI
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