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EP0177894A2
Expired / Lapsed
EP
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Method of producing metallic silicon particularly for use in the photovoltaic industry
Assignee: PRAGMA SpA
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Filing: 1985-10-03
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Granted: —
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Expires: 2005-10-03
Abstract
Abstract A method is disclosed for producing suitable silicon particularly for use in the manufacture of photovoltaic devices. The method consists of reducing quartz or quartzite with silicon carbide in a submerged arc furnace at a high temperature.
Inventors
- 👤 Paolo Fabris
- 👤 Renato Pirazzi
- 👤 Daniele Margadonna
- 👤 Massimo Rustioni
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 09:14
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/02; C01B33/021; C01B33/023
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
49 words
A method of producing metallic silicon particularly for use in the manufacture of photovoltaic devices, comprising the step of reducing silica in the quartz or quartzite forms by means of a carbonaceous reducer in a high temperature submerged arc furnace, characterized in that said carbonaceous reducer is silicon carbide.
Claim 2
Independent Claim
49 words
A method of producing metallic silicon particularly for use in the manufacture of photovoltaic devices, comprising the step of reducing silica in the quartz or quartzite forms by means of a carbonaceous reducer in a high temperature submerged arc furnace, characterized in that said carbonaceous reducer is silicon carbide.
Claim 3
Dependent Claim
67 words
A method according to claim 1, characterized in that said silicon carbide is obtained in electric furnaces of the resistance type by using a mixture of siliceous sand and/or amorphous silica and/or quartz and/or quartzites, in ground form and having a high purity, with B and P contents ≤ 1 and 5 ppmw, respectively, and carbon black with B and P contents 0.05 and 0.5 ppmw, respectively.
Claim 4
Dependent Claim
18 words
A method according to claim 2, characterized in that said mixture has a lower granulometry than 1 mm.
Claim 5
Dependent Claim
23 words
A method according to claim 2, characterized in that said electric resistance furnaces employ graphite electrodes having an ash content 0.5% by weight.
Claim 6
Dependent Claim
27 words
A method according to either claim 1 or claim 2, characterized in that said silicon carbide has B and P contents ≤ 3 and 10 ppmw, respectively.
Claim 7
Dependent Claim
26 words
A method according to claim 1, characterized in that the electrode feeding rate is, throughout the process, less than 70 kg electrode per ton silicon produced.
Claim 8
Independent Claim
37 words
A method according to any of the preceding claims, characterized in that it comprises the step of adding to said mixture, substances adapted to react with the impurities included in said mixture, to yield gaseous reaction products.
Claim 9
Dependent Claim
38 words
A method according to claim 7, characterized in that said substances adapted to react with said impurities are selected from solid sodium chloride with chlorine gas, and that said gaseous reaction products are the chlorides of said impurities.
Claim 10
Dependent Claim
20 words
Metallic silicon particularly for use in the manufacture of photovoltaic devices obtained by the method as disclosed and claimed herein.
References Cited (Backward Citations)
No citation records indexed.
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