Abstract: Granular polysilicon is fed into a screening plant, divided into two or more fractions by means of one or more screen surfaces, and thereby classified and dedusted wherein a throwing motion of the granular polysilicon in the screening plant removes adhering dust particles from the granular polysilicon, the removed dust particles are taken off from the screening plant by means of a gas flow supplied to the screening plant, and the screening plant is of gas-tight design and supply and takeoff of the gas flow are effected such that the screening plant is at a positive pressure compared to the surroundings.

Abstract: Segregation of silicon granules in the fluidized bed production of polycrystalline silicon is achieved by successively transferring granular polycrystalline silicon through a plurality of vessels designed for funnel flow of granular material. The transfers may occur prior to introduction of feed particles into the reactor, or the enlarged granules from the reactor may be thus transferred to improve product size uniformity.

Abstract: Granular polysilicon is fed into a screening plant, divided into two or more fractions by means of one or more screen surfaces, and thereby classified and dedusted wherein a throwing motion of the granular polysilicon in the screening plant removes adhering dust particles from the granular polysilicon, the removed dust particles are taken off from the screening plant by means of a gas flow supplied to the screening plant, and the screening plant is of gas-tight design and supply and takeoff of the gas flow are effected such that the screening plant is at a positive pressure compared to the surroundings.

Abstract: Segregation of silicon granules in the fluidized bed production of polycrystalline silicon is achieved by successively transferring granular polycrystalline silicon through a plurality of vessels designed for funnel flow of granular material. The transfers may occur prior to introduction of feed particles into the reactor, or the enlarged granules from the reactor may be thus transferred to improve product size uniformity.