アークプラズマによるコークス内装鉄鉱石ペレットの溶融還元

抄録

The possibility of direct steelmaking utilizing smelting reduction of iron ore by coke was investigated by using argon plasma jet as a heat source. Coke powder was included in an iron ore pellet for the promotion of reduction and the weight of pellets charged ranged from 1.2 to 3.8 kg. The typical composition of metals obtained with the slag containing 23%Fe and 0.0020.005%P is 0.5%C, 0.2%S and 0.018%P, the process being accompanied by the significant gaseous desulfurization and dephosphorization. This may be attributed to the carrying effect of gaseous species of S and P by CO which vigorously evolves on the very rapid reduction of iron ore at high temperatures due to plasma heating, and to good contact between ore and coke in pellets. The addition of flux such as CaO and CaF₂ improved the final composition of metals to yield 0.15%C, 0.003%P and 0.05%S.