METHOD FOR ESTIMATING CARBON CONCENTRATION IN MOLTEN STEEL IN RH REFINING

摘要

PURPOSE:To estimate carbon concn. in molten steel without executing integral calculation of carbon concn. in waste gas by arranging a waste gas analyzer, argon gas and oxygen flow meters in an waste gas pipe and calculating the carbon concn. in the molten steel based on nitrogen concn. and leaked oxygen quantity, etc., in the waste gas. CONSTITUTION:The waste gas analyzer 10 is arranged in the waste gas pipe 8 in a vacuum vessel 3 to measure the nitrogen concn. in the waste gas. Further, the flow meters 9a, 9b for Ar gas supplied into the vacuum vessel 3 and oxygen for raising temp., are arranged to measure the flow rates of Ar gas and oxygen. Successively, based on the flow rate of the above Ar gas, the leaked oxygen quantity is calculated, and based on this and the oxygen concn. in the above waste gas, the oxygen quantity measured with the oxygen flow meter 9b and the above Ar gas flow rate, the calculation is executed. Then, the carbon concn. in the molten steel is estimated without executing the integral calculation of the carbon concn. in the waste gas.