US3615340A
Expired / Lapsed
US
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Quenching and passivation of particulate metals
Assignee: ExxonMobil Technology and Engineering Co
•
Filing: 1968-11-18
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Granted: 1971-10-26
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Expires: 1988-11-18
Abstract
Abstract A process is disclosed for rendering active particles of reduced iron ores resistant to oxidation by treating the particles in a fluidized bed at elevated temperatures with mildly oxidizing gases.
Inventors
- 👤 Beverly B Fuqua
- 👤 William J Metrailer
- 👤 Marnell A Segura
- 👤 Earl E Turner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:29
CPC Classifications
B; B22; B22F; B22F1/00; B22F1/14; B22F1/145
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
18 words
The process of claim 1, wherein said bed temperatures range from about 150* F. to about 450* F.
Claim 2
Dependent Claim
43 words
The process of claim 1 wherein said metal particles are continuously added to said bed at temperatures above about 650* F. and are quenched to bed temperatures ranging from about 225* F. to about 600* F., by spraying liquid water into said bed.
Claim 3
Dependent Claim
21 words
The process of claim 3, wherein said particles are quenched to temperatures ranging from about 250* F. to about 450* F.
Claim 4
Dependent Claim
48 words
The process of claim 3, wherein said particles of reduced ore are introduced into said bed at temperatures ranging from about 1000* F. to about 1800* F. and comprise principally particles ranging from about 10 to about 10,000 microns, averaging about 50 to about 400 microns, in size.
Claim 5
Dependent Claim
30 words
The process of claim 1, wherein up to about3.0 percent of the metal in said particles is reoxidized to form an oxide film which protects the particles against further oxidation.
Claim 6
Dependent Claim
19 words
The process of claim 6 wherein from about 0.1 percent to about 1.0 percent of said metal is reoxidized.
Claim 7
Dependent Claim
19 words
The process of claim 2 wherein said mildly oxidizing gas contains up to about 12 volume percent free oxygen.
Claim 8
Dependent Claim
19 words
the process of claim 8 wherein said mildly oxidizing gas contains about 1 to about 8 percent free oxygen.
Claim 9
Dependent Claim
25 words
The process of claim 1 wherein said particles are maintained in said bed for holding times ranging from about 5 minutes to about 1 hour.
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) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |