Patent ID: 8449848

Claim:
A system for producing polycrystalline silicon by decomposition of trichlorosilane, the system being substantially closed-loop with respect to trichlorosilane, the system comprising: a chlorination reactor in which hydrogen chloride is contacted with silicon to produce trichlorosilane and silicon tetrachloride; a fluidized bed reactor in which trichlorosilane is decomposed to produce polycrystalline silicon; a hydrogenation reactor in which silicon tetrachloride and hydrogen are introduced to produce trichlorosilane; a hydrogenated gas separator to which hydrogenated gas from the hydrogenation reactor is directly introduced, the hydrogenated gas comprising trichlorosilane, hydrogen chloride, unreacted hydrogen and unreacted silicon tetrachloride, wherein the hydrogenated gas separator separates trichlorosilane and unreacted silicon tetrachloride from hydrogen and unreacted hydrogen chloride; and a purification system to which trichlorosilane and silicon tetrachloride are directly introduced from the chlorination reactor to separate trichlorosilane and silicon tetrachloride.