On the Equilibrium among Silicon in Molten Iron, Blast Furnace Slag and H_2-H_2O Mixed Gas. III : Investigation of the Equilibrium of the Reaction (SiO_2)CaO-Al_2O_3(Sat.)+2H_2=Si+2H_2O

Abstract

Using a pure Al_2O_3 crucible, author measured the following reaction under the conditions of 3Al_2O_3-2Al_2O_3, Al_2O_3 Or 3CaO-5Al_2O_3 saturation at the temperatures of 1, 550 and 1, 600℃, (SiO_2)CaO-Al_2O_3 (sat.) + 2H_2 =Si+2H_2O Further, the activities of SiO_2 in the molten slags of SiO_2-CaO-Al_2O_3 ternary system were calculated from the equilibrium values of Si in molten iron at a given temperature and gas ratio pH_2/pH_2O, where the pure β-Cristobalite was taken as the standard state. The author illustrated the relation of the equilibrium among Si in molten iron, activity of SiO_2 of the SiO_2 -CaO-Al_2O_3 molten slag saturated with Al_2O_3 and H_2-H_2O mixed gas. Finally author determined the liquidus lines in the presence of molten iron at temperatures of 1, 500°and 1, 600℃on the Al_2O_3 side of SiO_2 -CaO-Al_2O_3 ternary diagram from the equilibrium compositions of slags