Patent US3617256A successfully refreshed from Google Patents.
US3617256A
Expired / Lapsed
US
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Process for simultaneously producing powdered iron and active carbon
Assignee: FMC Corp
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Filing: 1968-02-28
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Granted: 1971-11-02
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Expires: 1988-02-28
Abstract
Abstract Iron, in the form of iron powder or a soft readily powdered agglomerate thereof, is prepared simultaneously with powdered active carbon, by heating an iron oxide, in the form of powder or a soft readily powdered agglomerate thereof with a stoichiometric excess of a powdered coal char which will react with carbon dioxide at the temperature employed at a rate above 10 percent per hour, at a temperature controlled so that the charge is maintained throughout the reaction at between 1,775* F. and 1,875* F. The temperature is most readily maintained in production units by passing the gases used to supply the necessary extraneous heat across the path of travel of the charge, rather than along the path of travel.
Inventors
- 👤 Robert T Joseph
- 👤 Jack Trechock
- 👤 Erik Saller
- 👤 Josiah Work
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:49
CPC Classifications
C; C21; C21B; C21B13/00; C21B13/0066; C21B13/0046; C21B13/0086; Y; Y02; Y02P; Y02P10/00; Y02P10/10; Y02P10/134
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
21 words
The method of claim 1 in which the reductant is used in a stoichiometric excess of between 50 and 500 percent.
Claim 2
Dependent Claim
24 words
The method of claim 1 in which the reaction mixture is heated by gases which travel across the path of the moving reduction mixture.
Claim 3
Dependent Claim
23 words
The method of claim 1 in which the excess reductant is separated from the product by mechanical means and then by magnetic means.
Claim 4
Dependent Claim
188 words
In the process for producing iron from iron ores by reduction with carbon at temperaturEs below the melting point of the iron, the improvement which permits the reduced iron to be recovered in the same particle size consist as the iron ore which is fed, and the excess carbon used as the reductant in the reaction to be activated into an active carbon powder with an iodine number of 500 or more, which comprises using the oxide either in the form of powder or a loose open-pored easily powdered agglomerate of such a powder, using a powdered reductant which is a char of a coal below the rank of anthracite which has a CO2 reactivity at the reduction temperature in excess of 10 percent per hour and contains at least 1 percent hydrogen, the reductant being in at least 25 percent and not over 500 percent stoichiometric excess over the iron, and maintaining the ore and the reductant in mixed condition at a temperature between 1,775* and 1,875* F., maintained by an internal stream of hot gas, for between 1/2 and 5 hours, to effect nearly total reduction.
Claim 5
Dependent Claim
49 words
The method of claim 5 in which the iron ore is fed as a loose open-pored easily powderable agglomerate, and the reductant is of smaller particle size, and in which the excess reductant is separated from the reduced product and recovered at least in part as active carbon product.
Claim 6
Dependent Claim
29 words
The method of claim 6 i which the agglomerate separated from the reductant is broken up and the iron powder therein is separated from the gangue by magnetic means.
Claim 7
Dependent Claim
47 words
The method of claim 2, in which the excess reductant is separated from the product by mechanical means and then by magnetic means. 9 The method of claim 3, in which the excess reductant is separated from the product by mechanical means and then by magnetic means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |