Multiphase modelling of the reduction of quartz in a silicon carbide reactor

Traditional refining of silicon generates carbon dioxide emissions that are released into the atmosphere. An alternative process under experimental exploration uses a lower temperature, which leads to different chemical reactions dominating. The goal of this alternate process is to reduce the greenhouse gas emissions, and produce silicon carbide, which can then be efficiently processed into silicon. We develop a macro-scale multiphase model for chemical and transfer processes within the reactor. We derive governing equations for the concentration of silicon monoxide, carbon monoxide, and carbon dioxide, and conservation equations for quartz, carbon, and silicon carbide. We solve the leading-order system numerically, and show examples of the conversion of carbon to silicon carbide.