US4526612A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing ferrosilicon
Assignee: SKF Steel Engineering AB
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Filing: 1983-08-25
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Granted: 1985-07-02
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Expires: 2003-08-25
Abstract
Abstract Ferrosilicon is manufactured from a material containing silica and a raw material containing iron by injecting these materials, possibly together with a reducing agent, with the help of a carrier gas into a plasma gas. The silica and the iron raw material, possibly with the reducing agent, heated in this way are then introduced with the energy-rich plasma gas into a reaction chamber surrounded by a solid reducing agent in lump form, the silica thus being brought to the molten state, being reduced and reacting with the iron to form ferrosilicon.
Inventors
- 👤 Sune Eriksson
- 👤 Sven Santen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:25
CPC Classifications
C; C22; C22B; C22B4/00; C22B4/005; C22C; C22C33/00; C22C33/003
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
99 words
A continuous method of manufacturing ferrosilicon which comprises continuously injecting a starting material substantially in fine grained form and containing a silica-containing material and an iron-containing material, with a carrier gas, into a plasma gas generated by a plasma generator; thereby heating the material and continuously introducing the silica- and iron-containing material so heated, with the plasma gas into a reaction chamber surrounded substantially on all sides by a solid reducing agent in lump form, thereby bringing the silica to molten state and reducing it to silicon and causing said silicon to combine with the iron to form ferrosilicon.
Claim 2
Dependent Claim
99 words
A continuous method of manufacturing ferrosilicon which comprises continuously injecting a starting material substantially in fine grained form and containing a silica-containing material and an iron-containing material, with a carrier gas, into a plasma gas generated by a plasma generator; thereby heating the material and continuously introducing the silica- and iron-containing material so heated, with the plasma gas into a reaction chamber surrounded substantially on all sides by a solid reducing agent in lump form, thereby bringing the silica to molten state and reducing it to silicon and causing said silicon to combine with the iron to form ferrosilicon.
Claim 3
Dependent Claim
26 words
A method according to claim 1, in which gas plasma is generated by allowing the plasma gas to pass an electric arc in a plasma generator.
Claim 4
Dependent Claim
17 words
A method according to claim 2, in which the arc in the plasma generator is generated inductively.
Claim 5
Dependent Claim
19 words
A method according to claim 1, in which the plasma gas comprises process gas recirculated from the reaction chamber.
Claim 6
Dependent Claim
22 words
A method according to claim 1 in which the solid reducing agent in lump form is added continuously to the reaction chamber.
Claim 7
Dependent Claim
26 words
A method according to claim 1 in which the solid reducing agent in lump form is selected from the group consisting of wood, coal and coke.
Claim 8
Dependent Claim
34 words
A method according to claim 1 in which the solid reducing agent in lump form is selected from the group consisting of brickets of petroleum coke, brickets of charcoal powder and lumps of charcoal.
Claim 9
Dependent Claim
18 words
A method according to claim 1 in which the starting material is introduced together with a reducing agent.
Claim 10
Dependent Claim
35 words
A method according to claim 8 in which the reducing agent introduced with the starting material is selected from the group consisting of charcoal powder, powdered petroleum coke and hydrocarbons in gas and liquid form.
Claim 11
Dependent Claim
24 words
A method according to claim 9 in which the reducing agent is selected from the group consisting of natural gas, propane and light benzine.
Claim 12
Dependent Claim
14 words
A method according to claim 1 in which the silica-containing material is quartz sand.
Claim 13
Dependent Claim
16 words
A method according to claim 1 in which the iron-containing material is one containing free iron.
Claim 14
Dependent Claim
23 words
A method according to claim 12, in which the iron-containing material is selected from the group consisting of iron pellets and iron filings.
Claim 15
Dependent Claim
16 words
A method according to claim 1 in which the iron-containing material is one containing ferric oxide.
Claim 16
Dependent Claim
14 words
A method according to claim 1 in which the iron-containing material is calcined pyrites.
Claim 17
Dependent Claim
20 words
A method according to claim 1 in which the silica and iron are compounded in one material as starting material.
Claim 18
Dependent Claim
21 words
A method according to claim 16 in which the starting material comprises fayalite slags, said slags comprising primarily 2FeO.SiO 2 .
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-01 | 1988-12-31 | 1989-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-01 | 1992-12-31 | 1993-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-01 | 1996-12-31 | 1997-07-02 | $7700.00 | Window Closed / Lapsed |