Method for producing polycrystalline silicon

1. A method for producing a polycrystalline silicon, comprising the steps of:

a) depositing the polycrystalline silicon by reacting a chlorosilane compound and a hydrogen together;

b) separating an exhaust gas which is discharged through step a) into a chlorosilane condensate and a gas component, wherein the chlorosilane condensate contains a fine silicon powder in an amount of 0.01% by mass to 0.3% by mass, wherein the gas component contains a hydrogen gas and a hydrogen chloride;

c) removing the fine silicon powder by passing the chlorosilane condensate containing the fine silicon powder through a filter by use of a slurry pump to prevent an accumulation of the fine silicon powder in a separation device and a pipe which are provided in steps after passage of the filter and damage to the slurry pump, and further to reduce adhesion of a silane oligomer to the filter; and

d) distilling the chlorosilane condensate after the fine silicon powder removal in step c) to obtain a chlorosilane compound and circulating the chlorosilane compound to step a).

2. The method as set forth in claim 1 , further comprising

circulating part of the chlorosilane condensate discharged from the slurry pump to step b).

3. The method as set forth in claim 2 , wherein:

the chlorosilane condensate is carried to the slurry pump after the chlorosilane condensate is passed through a strainer.

4. The method as set forth in claim 1 , wherein:

the filter has a pore size of 1 μm to 5 μm.