Patent ID: 8017099
Filing Date: 2011-09-13
Classification: C01B,C08G

Abstract:
1. A method for producing polycrystalline silicon, comprising: reacting trichlorosilane and hydrogen to produce polycrystalline silicon and a remainder comprising monosilanes, formula: SiH depositing the polycrystalline silicon on a surface of a red-hot silicon rod, and supplying said remainder and hydrogen to a conversion reactor and heating at a temperature within the range of 600 to 1,400° C. to convert silicon tetrachloride into trichlorosilane and said polymer into monosilanes, wherein said remainder produced by reacting trichlorosilane and hydrogen is introduced into a cooler to separate hydrogen and hydrogen chloride from said remainder; the resultant is introduced into a first distillation column to separate trichlorosilane; the column-bottom component of the first distillation column is introduced into a second distillation column to separate silicon tetrachloride; the column-bottom component of the second distillation column is introduced into a third distillation column to separate a polymer; and the polymer separated in the third distillation column and silicon tetrachloride separated in the second distillation column are introduced into the conversion reactor, and hydrogen is further introduced into the conversion reactor, to effect a reaction.