REFINING TREATMENT METHOD USING REFINING AGENT GENERATING COMBUSTIBLE GAS

摘要

PROBLEM TO BE SOLVED: To surely perform refining while minimizing emission of a combustible gas, which is emitted from a refining agent, to the atmosphere.;SOLUTION: A refining treatment method is executed as follows: blowing-in of a non-gas-generation refining agent is started before immersing a discharge port 6 of a blowing-in lance 3 into a molten iron, and the discharge port 6 of the blowing-in lance 3 is immersed into the molten iron; the immersion depth of the discharge port 6 is set at 50-200 mm, and blowing-in is switched from the non-gas-generation refining agent to a gas-generation refining agent; the solid-gas ratio for blowing-in of the gas-generation refining agent is made ≥3 kg/Nm³, and the immersion depth of the discharge port 6 is set at 200 mm; the immersion depth of the discharge port 6 is again set at 50-200 mm, and blowing-in is switched from the gas-generation refining agent to the non-gas-generation refining agent; and the solid-gas ratio for blowing-in of the non-gas-generation refining agent after the switching is made ≥3 kg/Nm³, and blowing-in is carried out in the molten iron for one minute or more.;COPYRIGHT: (C)2013,JPO&INPIT