Smelting of Iranian Ilmenite by Electro-Slag Crucible Melting (ESCM) Process

摘要

In this research ilmenite concentrate from kahnouj mine of Iran was successfully smelted by Electro-Slag Crucible Melting (ESCM) to produce TiO{sub}2-rich slag as primary product and pig iron as by-product. Recently, ESCM is used for smelting concentrates and ores. Because in this process the electrical conditions can be stabilize and the violent fluctuation of electrical current can be reduced. Therefore the performance of ESCM is better than electric arc furnace. Petroleum coke for reduction of iron oxides and mixture of CaF{sub}2, CaO, and Al{sub}2O{sub}3 as ESCM slag was used. Effect of parameters such as the ESCM slag to ilmenite weight ratio, charge amount variation and reduction time on iron recovery and slag compositions was considered. It was found that at stoichiometric amount of carbon and 1600°C～1650°C, optimum amount of ESCM slag to ilmenite weight ratio and reduction time is respectively 5% and 17 minutes. Amount of TiO{sub}2 in slag at optimum conditions were 70%. Increasing the charge weight resulted in increasing the reduction time for reach to fixed composition of slag. Presence of titanium sub-oxides (Ti{sub}2O{sub}3 and Ti{sub}3O{sub}5) caused the iron recovery to be reduced significantly.