METHOD AND APPARATUS FOR CARBOTHERMAL PRODUCTION OF HIGH-PURITY SILICON Russian patent published in 2015 - IPC C01B33/25 C30B29/06 B01J19/08 

FIELD: chemistry.

SUBSTANCE: method includes thermal reduction of quartzites to elementary silicon through a reducing gas mixture using plasma, wherein the process is carried out in a single step in counterflow of quartzites and the reducing agent, the reducing agent being a mixture of hydrocarbons and steam, the amount of which is not more than j the amount required for a conversion reaction, and the total amount of carbon contained in the hydrocarbons is at least 1.5 times more than the stoichiometrically required amount for full reduction of quartzites. The apparatus comprises an electric arc furnace 1, a plasmatron 3, a quartzite supply system 2, means of feeding the reducing agent 6; the plasmatron 3 with means of feeding the reducing agent 6 is located under a shaft 5 in the lower part of the furnace 1; the quartzite supply system 2 is placed in the upper part of the shaft 5, wherein the lower part of the furnace 1 is separated from the shaft space by a limiter 9, which controls the descent of quartzites from the shaft 5 into said lower part.

EFFECT: obtaining high-purity polycrystalline silicon using an environmentally safe method with high percentage output of silicon and low cost thereof.

2 cl, 1 dwg, 1 ex