Kinetics of formation of spinels in the MgO-FeO(Fe2O3)-Al2O3-Cr2O3 system

Abstract

The results of the analysis of the disperseness of the suspensions are plotted on a logarithmic probability graph (Fig. 4). We determine the tangent of the angle ~ characterizing the slope that the straight line makes with the abscissa (width of grain component) and the average-surface diameter of the particles day s using the formuladavs= lO0/(F, AQ/dav), where s isthemass fraction of the particles of a certain cut with an average particle size dav, %.The statistical treatment of the results of the analysis shows that the relative error in the determination of the average-surface diameter of the particles is ~-12%.The main error is caused by the degree of uniformity both in relation to the grain composition and also in relation to the concentration of solid phase per unit volume in the case of the analysis of the suspension of concentration 1.0-1.5 g/liter. CONCLUSIONSA method of determining the grain composition of suspensions of vitreous silica using a liquid sedimentograph has been developed and introduced at the Central Plant Laboratory of the Podolsk Refractory Products Plant. The results of the analysis can be evaluated from the tangent of the angle the straight line makes with the abscissa on the log-probability graph and the average surface diameter of the particles. The relative error in the determination of the average-surface diameter is -< 12%.Using this method it is possible to determine the disperseness of the suspensions made from A1203 and other materials characterized by a grain composition between 0.5 and 100/~m.