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The reduction and melting behavior of carbon composite iron ore hot briquette in shaft furnace are discussed. As these agglomerates are made by the use of thermal plasticity of coal, the reduction rate by chain reactions in interface between ore and coal could be increased. The carbon composite iron ore hot briquettes achieve 95 % reduction degree in about 10-min descent time to the 1 100°C heat reserve zone bottom end and the drop of molten iron temperature is kept to 20°C. As a result, it is expected that these new agglomerates could decrease the fuel rate and discharging amount of CO 2 as well as have a possibility of extension of furnace life. Finally the paper ends by shaping the future of blast furnace on environmental phases for the new century. Especially,it is expected that carbon composite iron ore hot briquette lowers temperature of heat reserve zone and shortens the length, suggesting the possibility of shortening of the reserve zone (inactivity zone), that is, shortening of the blast furnace height.KEY WORDS: blast furnace; carbon composite iron ore briquette; hot briquetting; reaction rate; innovative ironmaking.

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Effective thermal conductivity of metallurgical coke was measured in the temperature range from I OOto 1 400'C by using the laser flash method. Effective

Practical ways of estimating temperatures of coke flowing into raceway as well as the gas core depth validated by direct measurement were suggested for the purpose of better describing the combustion behaviors of injected coal fine in blast furnace raceway. The numerical simulation model was refurnished with the scheme, and helped clarifying an intriguing effect of coal gasification or decomposition degrees before exiting tuyere tip on attained combustibility of coal at raceway boundary.Another scheme for quantitative expression of pressure losses caused exclusively by coal fine residence in and around raceway was also developed by shutting off coal injection for minutes at practical operation. The obtained results lead to developing the advanced tuyere, CD (converged and diverged) tuyere which enabled reducing the interaction between injectants and hot blast inside tuyere and thus improving overall gas permeability even under conditions of massive coal injection over 250 kg/tHM.