A Model for FeSiMg Alloy Production by Reduction Technique

Abstract

Ferrosilicon magnesium is basic foundry alloys used for the production of ductile cast iron. Magnesium content plays an important role in the produced alloy grades from dolomite ore. The focus of the present work is to simulate mathematical model to predict magnesium content in the ferrosilicon magnesium, which produced by silicothermic reduction of calcined dolomite. The basic assumptions of this model are: constant low viscosity of molten charge, the reaction is irreversible of second order and the reaction is isothermal. The reaction is based on the following equation: 2MgO+2Si →Mg 2 Si+SiO 2 The results of previous work was found to be in a good coincidence with the predicted values by the model [Mg]=(MgO 0 )[Si 0 ][e Kt[(MgO 0 )-[Si 0 ]] -1]/ (MgO 0 )[e Kt[(MgO 0 )-[Si 0 ]] -[Si 0 ]] where [Mg] is the concentration of magnesium metal in ferrosilicon magnesium alloy in mol/L. [Si 0 ] and (MgO 0 ) are the initial concentration of silicon and magnesium oxide in charge in mol/L, while t is time in second, K is the reaction rate constant ( 3.26588x10 -7 L Sec -1 mol -1 ). The predicted values are greater than the experimental values; this may be attributed to the use of concentration instead of the activity. The predicted values of magnesium content in ferrosilicon magnesium alloy are in a good agreement with the experimental results obtained in previous work at low viscosity.