Modelling of the reactive synthesis of ultra-fine powders in a thermal plasma reactor

A two-dimensional, chemical kinetics and aerosol growth model is developed for the comprehensive simulation of the reactive synthesis of ultra-fine particles in a thermal plasma reactor. The model solves the velocity and temperature fields that are coupled to the equations describing the electromagnetic induction field. Conservation equations for the plasma species consider the multi-component diffusion and chemical reactions. For the condensable product, an additional term is introduced, due to the phase change. Particle growth occurs via homogeneous nucleation and surface condensation, and an evaporation term is considered for concentrations below saturation. The model is applied to the synthesis of silicon metal powders by the dissociation of . The effect of the input power and that of the radial quenching are investigated by comparison with a simulation base case.