SU327780A1 - Charge for obtaining silicon - Google Patents

Description

Known solids for obtaining silicon of the following composition, wt.%: Quartz (lump) 62.0 Charcoal 32.6 Petroleum coke 5.4

The proposed charge is characterized in that, instead of charcoal, carbon black is added to the composition and binder with the following content of components, wt.%: Quartz sand 60-75 Oil coke 12-24 Soot 6-18

  Binding 0-20

This allows to intensify the technological process, improve the quality and reduce the cost of silicon produced.

In the proposed charge, it is advisable to use petroleum coke with a particle size of 0-6 mm according to MP.TU 12 and 105-64 and soot with a specific surface area of 10-ZOM / g

When using one carbon black (without the addition of petroleum coke), due to its high activity, an earlier reduction of silicon oxide (to monoxide (SiO) and volatilization of the latter is observed. The addition of petroleum coke sweeps the reduction zone to higher temperatures, where there are favorable conditions for reduction of silicon monoxide to carbon silicon and further to metallic.

Reducing losses of monos sysn silicon contributes to the improvement of specific indicators on the consumption of raw materials and electricity and the increase in thermal efficiency of an electric furnace. At the same time, fine-grained petroleum coke is several times cheaper than soot.

The use of a combined oil coke and soot reduction is possible using a double method.

1. Oil coke and soot are mixed with quartz sand and okuskovayut in

in the form of briquettes or pellets. Okuskovannaya charge is loaded into an electric furnace.

2. Oil coke and soot mixed and agglomerated. Okuskovanna mixture

loaded into an electric furnace together with quartz sand.

It is proposed to use as a binder in the agglomeration of the charge: a) sulphite-alcohol concentrates

bards based on sodium, magnesium or ammonium cations (which do not introduce harmful impurities) in an amount up to 10% by weight of the dry SALT; b) coal or petroleum pitch in an amount up to 20%

If necessary, to control the porosity of the briquettes (granules), organic loosening known additives can be introduced into the mixture: sawdust, chips, etc.

Example. The following materials were used as starting materials: quartz sand of composition ui0299.8%,, 02% soot granulated TM-15 and fine-grained petroleum coke.

The binder was a concentrate of sulfite-alcohol stillage brand KBJ on a sodium basis in an amount of 8% of the dry weight of the mixture.

The experiments were carried out on an electric arc furnace of about 100 KW. The furnace is single phase with one electrode and a conductive bottom. Electric mode: voltage 38-42 V, current from 2500 to 3000 a.

When using this mixture, silicon of a zero grade of 90% and first grade 10 was obtained; silicon cost reduced by 50-60

rub / ton The specific power consumption was from 22.3 to 23.7, kWh / kg.

Claims (2)

Invention Formula Wax to obtain cream, including quartz and petroleum coke, characterized in that, in order to improve the quality and reduce the cost of silicon produced, soot and binder are added to its composition, with the following content of components, wt.%: Quartz sand 60-75 Oil coke 12-24 Sazhab-1B Binding 0-20 2. A mixture according to Claim 1, characterized in that the binder is selected from the group comprising a sulfite alcohol bard based on magnesium cation, a sulfite alcohol bard based on the ammonium cation, coal tar pitch, and oil pitch.