SLAG STRUCTURES AND PROPERTIES BY SPECTROSCOPIC ANALYSIS: EFFECT OF WATER VAPOR RELEVANT TO A NOVEL FLASH IRONMAKING TECHNOLOGY

摘要

In an effort to develop a novel flash ironmaking process, the chemistry of selected slags was investigated. In different ironmaking processes, the molten bath (iron-slag bath) is expected to be in contact with gas atmospheres of H_2/H_2O, CO/CO_2/H_2/H_2O, and CO/CO_2. The latter was investigated to allow comparison with the blast-furnace conditions. The slag composition was selected to resemble that of the blast furnace with CaO/SiO_2 in the range 0.8 to 1.4. The temperature range was 1550 to 1650°C. The oxygen partial pressure was maintained in the range 10~(-10) to 10~(-9) atm. The effect of water vapor on the chemistry of the slag as well as the equilibrium reactions involving the slag has been studied for the first time. H_2O dramatically affects the chemistry of the slag and strongly affect the phase equilibria in the slag as well as the equilibrium distribution of elements between slag and molten metal.