Removal of off-gases from oxygen steel converters

Abstract

Abstract OFF-GAS IS REMOVED FROM AN OXYGEN STEEL CONVERTER THROUGH AN AIR-VENTILATED HOOD. OXYGEN IN THE INDUCTED AIR REACTS WITHIN THE HOOD WITH CARBON MONOXIDE IN THE OFF-GAS, AND THE RESULTING HOT GAS MIXTURE IS QUENCHCOOLED, USUALLY BY DIRECT CONTACT WITH WATER. THE FLOW RATE OF THE DRY GAS COMPONENT OF THE RESULTING COLD GAS MIXTURE IS MEASURED AND THE MIXTURE FLOW RATE IS REGULATED, TO PROVIDE ESSENTIALLY CONSTANT DRY GAS FLOW RATE DURING ALL INTERVALS BETWEEN AND DURING THE BLOW PERIOD AND THE MAGNITUDD OF THE FLOW RATE IS CONTROLLED AT A LEVEL WHICH PROVIDES AN EXCESS OF AIR AT THE ONSET INTERVAL AND TERMINATION INTERVAL OF THE BLOW PERIOD, AND A DEFICIENCY OF AIR AT THE PEAK OF THE BLOW PERIOD. THE GAS MIXTURE REMOVED FROM THE HOOD AT THE ONSET AND TERMINATION INTERVALS OF THE BLOW PERIOD CONTAINS AN EXCESS OF FREE OXYGEN, WHILE THE GAS MIXTURE REMOVED AT THE PEAK OF THE BLOW PERIOD CONTAINS AN EXCESS OF CARBON MONOXIDE. BETWEEN THE PERIODS OF EXCESS FREE OXYGEN CONTENT AND EXCESS CARBON MONOXIDE CONTENT, AN INERT GAS MIXTURE PRINCIPALLY CONTAINING NITROGEN AND CARBON DIOXIDE IS REMOVED FROM THE HOOD. THE INTERVAL OF INERT GAS MIXTURE FLOW EFFECTIVELY SEPARATES THE GAS MIXTURE CONTAINING FREE OXYGEN FROM THE GAS MIXTURE CONTAINING CARBON MONOXIDE, AND PERMITS THE REMOVAL OF OFF-GASS FROM THE AIRVENTILATED HOOD USING A DEFICIENCY OF INDUCTED AIR BELOW THE STOICHIOMETRIC REQUIREMENT FOR THE TOTAL CARBON MONOXIDE COMBUSTION AT THE PEAK OF THE BLOW PERIOD, WHILE PREVENTING THE FORMATION OF AN EXPLOSIVE GAS MIXTURE IN THE GAS STREAM REMOVED FROM THE HOOD THROUGHOUT THE BLOW PERIOD. AN IMPORTANT FEATURE OF THIS INVENTION IS THE COMLPOLETE SEPARATION AND LACK OF DEPENDENCY OF THE STEEL MAKING FUNCTION ON THE GAS COLLECTING AND CLEANING FUNCTION. D R A W I N G

Inventors

• 👤 Howard P Willett

Bibliographic Details