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The distillation of trichlorosilane takes place during the trichlorosilane synthesis process; the chlorosilane liquid separated through the dry separation process of syngas is fed into the raw material chlorosilane tank in the chlorosilane storage process； The chlorosilane liquid generated in the silicon trichloride reduction process, and separated through the dry separation process of the reduction exhaust gases, is sent to the reduction chlorosilane storage tank in the chlorosilane storage process ； The chlorosilane liquid, which is produced in the silicon tetrachloride hydrogenation process and separated through the dry separation process for hydrogenated gases, is sent to the hydrogenated chlorosilane storage tank in the chlorosilane storage process. The raw chlorosilane liquid, reduced chlorosilane liquid, and hydrogenated chlorosilane liquid are each pumped out and fed into different distillation columns in the chlorosilane separation and purification process. The raw chlorosilane liquid supplied from the raw chlorosilane storage tank is preheated in a preheater before being fed from the middle section into the first-stage distillation tower to carry out distillation to remove low-boiling substances. The non-condensable gases and a portion of dichlorodihydrosilicon are discharged from the tower and sent to the waste gas treatment process for processing ； The overhead distillate is a silicon trichloride condensate containing low-boiling and high-boiling impurities, which is fed to the two-stage distillation column by pressure difference ； The bottom of the tower yields silicon tetrachloride containing impurities, which is sent to a silicon tetrachloride recovery tower for treatment. The secondary distillation column is a reactive distillation unit; it treats silicon trichloride with moist nitrogen to convert the hydrolytically sensitive impurity compounds into less volatile forms, thereby enabling their removal through distillation. Level 2 distillation is a dual-series production line. The non-condensable gases emitted from the top of the stage 2 distillation tower are also sent to the waste gas treatment process for processing ； The silicon trichloride hydrolysate from the tower top distillate is sent to the precipitation tank by means of pressure difference ； The slurry containing suspended solids from the bottom of the tower is pumped to the silicon tetrachloride recovery tower for treatment. The purpose of stage 3 distillation is to remove low-boiling impurities from trichlorosilane. After passing through the three-stage feed preheater, the trichlorosilane solution enters the middle section of the three-stage distillation tower. The condensate containing dichlorosilane and trichlorosilane at the top of the tower flows by gravity to the secondary trichlorosilane tank ； The liquid at the bottom of the tower is trichlorosilane, which is pumped into a 4-stage distillation tower. The purpose of stage 4 and stage 5 distillation is to remove the high-boiling-point impurities from trichlorosilane in two steps. The liquid from stage 3 is fed into the middle section of the stage 4 distillation column. The trichlorosilane condensate from the top of stage 4 flows, driven by gravity, to the distillation tower of stage 5, where the second stage of removal of high-boiling-point impurities takes place. The trichlorosilane condensate from the top of stage 5 is sent to the five-stage condensate tank. Once a tank is filled, an analysis is conducted to determine whether the trichlorosilane meets the impurity content requirements for industrial-grade trichlorosilane; if the analysis is satisfactory, the refined industrial-grade trichlorosilane flows from the tank to the stage 8 distillation tower due to gravity. Trichlorosilane containing high-boiling-point impurities, discharged from the reactors at level 4 and level 5, is pumped into the secondary trichlorosilane tank. Silicon trichloride distilled from the top of stage 5 undergoes a final removal process in stage 6 distillation column to eliminate the high-boiling-point impurities from it. The distillate from stage 6 is refined trichlorosilane free of high and low boiling point impurities; after its analysis confirms it meets the quality requirements for polysilicon production, it flows via gravity to the polysilicon production process. The bottom liquid from the tank is trichlorosilane containing high-boiling-point impurities, which is pumped to the secondary trichlorosilane tank. The reduced chlorosilane condensate enters the 7-stage distillation column via a 7-stage feed preheater. The overhead distillate is trichlorosilane, which flows by gravity to the 8th stage distillation column ； The liquid in the bottom of the tower is silicon tetrachloride; after analysis confirms that it meets the quality requirements, part of it is pumped to the silicon tetrachloride hydrogenation process, while another part is sent to the industrial-grade silicon tetrachloride storage tank used in the chlorosilane storage process. A distillation column of grade 8 is used to remove high-boiling impurities from chlorosilanes. The distillate from the tower is refined cyclic trichlorosilane, which is sent to an 8-stage condenser. After analysis confirms that it meets the quality requirements, the refined trichlorosilane is circulated back to the polysilicon production process via gravity. The bottom liquid from the tank contains silicon trichloride with high-boiling fractions, which is pumped to the secondary silicon trichloride tank. The chlorosilane condensate obtained after the hydrogenation of silicon tetrachloride is continuously fed into a 9-stage distillation column via 9-stage feed preheaters. The distillate at the top of the tower is trichlorosilane, which is continuously sent to a 10-stage distillation column for further purification. The bottom liquid of the tower is silicon tetrachloride containing high-boiling-point impurities, which is continuously pumped to the 11-stage distillation column. Silicon trichloride distilled from the top of the 9th-stage distillation tower has its high-boiling-point impurities removed in the 10th-stage distillation tower. The overhead distillate from the 10-stage distillation tower is refined cyclic trichlorosilane, which is sent to the 10-stage condensate tank. After analysis confirms that it meets the quality requirements, the refined trichlorosilane is circulated back to the polysilicon production process via gravity. The bottom liquid from the tank contains silicon trichloride with high-boiling fractions, which is pumped to the secondary silicon trichloride tank. The feed to the 11th-stage distillation column is the bottom liquid from the 9th-stage distillation column. The distillate from the tower is refined recycled silicon tetrachloride; after analysis confirms it meets the quality requirements, it is pumped to the silicon tetrachloride hydrogenation process. The bottom liquid from the tower is silicon tetrachloride containing high-boiling-point impurities, which is sent to the industrial-grade silicon tetrachloride storage tank in the chlorosilane storage process.