MODELING OF THE REACTIVE SYNTHESIS OF ULTRA-FINE POWDERS IN A THERMALPLASMA REACTOR

A two-dimensional, chemical kinetics and aerosol growth model is devel oped for the comprehensive simulation of the reactive synthesis of ult ra-fine particles in a thermal plasma reactor. The model solves the ve locity and temperature fields that are coupled to the equations descri bing the electromagnetic induction field. Conservation equations for t he plasma species consider the multi-component diffusion and chemical reactions. For the condensable product, an additional term is introduc ed, due to the phase change. Particle growth occurs via homogeneous nu cleation and surface condensation, and an evaporation term is consider ed for concentrations below saturation. The model is applied to the sy nthesis of silicon metal powders by the dissociation of SiCl4. The eff ect of the input power and that of the radial quenching are investigat ed by comparison with a simulation base case.