In this work, a CFD model for simulating industrial scale particle-fluid systems is used to model a fluidized bed reactor for the deposition of high-purity silicon from silane gas. The performance of these reactors is directly dependent on a large number of factors and parameters which make the design and optimization of the deposition reactors an engineering challenge. Using the reactor design and experimental data from work performed at the Jet Propulsion Laboratory as a basis for validation, the CFD model was found to accurately model the deposition rate, silicon fines production, and temperature distribution within a silane deposition reactor. Additionally, the CFD model is demonstrated to be an effective tool for comparing different reactor designs on the basis of fluidization mode, reaction conversion, heat transfer, and particle mixing.