Patent attributes
To provide a method for producing polycrystalline silicon at relatively low cost, wherein the amount of waste generated is reduced by decreasing the amount of waste generated in producing polycrystalline silicon from silicon chloride by a method of reduction and increasing the amount of reused auxiliary raw materials. In the production of polycrystalline silicon using a gas phase reaction of a silicon chloride gas and a reducing agent gas, a chlorine gas is blown into an exhaust gas discharged from a reaction device to initiate a reaction, an unreacted reducing agent and silicon particles contained in the exhaust gas are chlorinated, and then a reducing agent chloride contained in the exhaust gas is separated from the other impurities and recovered.
