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COURSE50 project standing for " C02 ultimate reduction in steelmaking process by innovative technology for cool earth 50",which is one of the World Steel Association s CO2 breakdown programs,has been promoted in Japan since 2008.This program aims at developing technologies to decrease CO2 emissions through hydrogen reduction of iron ore as well as capture-separation and recover.The project consists of two major research activities.One is development of technology to reduce CO2 emissions from blast furnaces by using hydrogen formed after reforming coke oven gas ( COG).The other is development of technology to separate and recover CO2,involving with development of a high-efficiency CO2 absorption method and technology to utilize unused waste heat in steelmaking plants for CO2 separation and recovery.Concerning the former research activity,reduction tests by using softening-melting tester and shaft reaction simulator to demonstrate the condition of shaft injection of reformed COG have been conducted.Results showed that permeability resistance at wall region of furnaces was significantly improved by injection of reformed-COG having high amount of hydrogen from shaft as a result of an increase of indirect reduction.It was found that the desirable supplying conditions of reformed-COG as follows,feeding rate of reformed-COG above 200 Nm3/t-HM and interior distribution ratio of injected gas above 200%.Results of shaft reaction simulator showed that indirect reduction contributed an enhancement of total reduction degree.Furthermore,two dimensional gas-solid flow cold model having 1/10 scales of a real furnace was adapted to analyze the gas distribution within blast furnaces with shaft injection.The influences of gas flow rate,flow velocity on gas distribution within furnaces were studied.It was confirmed that injected gas diffused in the range from 10 t0 20 percent radius distance from the furnace wall.Those results indicated that technology of injection of reformed-COG from shaft had a large possibility of reducing carbon consumption of blast furnaces,resulting in decrease CO2 emissions in ironmaking process with thanks of higher reaction efficiency of hydrogen reduction compared with that of CO reduction.