US4264430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Three-stage coal liquefaction process
Assignee: Chevron USA Inc
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Filing: 1979-10-22
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Granted: 1981-04-28
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Expires: 1999-10-22
Abstract
Abstract Disclosed is a three-stage process for liquefying coal. In the process subdivided coal is slurried with a hydrogen-lean hydrogen-donor solvent and passed through a dissolving zone at a temperature in the range 400°-480° C. and at a space velocity in the range 2-150 hr. -1 to substantially dissolve said coal. The effluent from the dissolver is stabilized with a hydrogen-rich hydrogen-donor solvent in a stabilization zone at a temperature in the range of 400°-440° C. and at a space velocity in the range 1-12 hr. 31 1 to partially hydrogenate the dissolved coal. A portion of the effluent from the stabilizer is recycled for use as hydrogen-lean hydrogen-donor solvent and the remainder is passed to a catalytic reaction stage operating under hydrocracking conditions to produce the net product and hydrogen-rich hydrogen-donor solvent.
Inventors
- 👤 Christopher W. Kuehler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:51
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/002
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
178 words
A three-stage process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a lean hydrogen-donor solvent; passing said slurry through a dissolving stage at a temperature in the range of 400°-480° C. and at a slurry hourly space velocity in the range of 2-150 hr. -1 to substantially dissolve said coal; passing effluent from said dissolving stage with a rich hydrogen-donor solvent through a stabilization stage at a temperature in the range of 400°-440° C. and at a liquid space velocity in the range of 1-12 hr. -1 to partially hydrogenate the dissolved coal; separating a portion of the effluent from said stabilization stage for use as lean hydrogen-donor solvent; passing the remainder of said effluent from said stabilization stage through a catalytic reaction stage containing hydrocracking catalyst and operating under hydrocracking conditions including a hydrogen partial pressure in the range of 35-700 atmospheres and at a temperature in the range of 345°-425° C.; and separating a portion of the effluent from said catalytic reaction zone for use as a rich hydrogen-donor solvent.
Claim 2
Dependent Claim
178 words
A three-stage process for liquefying coal which comprises: forming a coal-solvent slurry by mixing subdivided coal with a lean hydrogen-donor solvent; passing said slurry through a dissolving stage at a temperature in the range of 400°-480° C. and at a slurry hourly space velocity in the range of 2-150 hr. -1 to substantially dissolve said coal; passing effluent from said dissolving stage with a rich hydrogen-donor solvent through a stabilization stage at a temperature in the range of 400°-440° C. and at a liquid space velocity in the range of 1-12 hr. -1 to partially hydrogenate the dissolved coal; separating a portion of the effluent from said stabilization stage for use as lean hydrogen-donor solvent; passing the remainder of said effluent from said stabilization stage through a catalytic reaction stage containing hydrocracking catalyst and operating under hydrocracking conditions including a hydrogen partial pressure in the range of 35-700 atmospheres and at a temperature in the range of 345°-425° C.; and separating a portion of the effluent from said catalytic reaction zone for use as a rich hydrogen-donor solvent.
Claim 3
Dependent Claim
21 words
A process as recited in claim 1, wherein said dissolving and stabilization stages are free of externally-supplied catalyst and contact particles.
Claim 4
Dependent Claim
32 words
A process as recited in claim 2, further comprising removing at least a portion of the coal residue from said lean hydrogen-donor solvent before mixing the lean solvent with the subdivided coal.
Claim 5
Dependent Claim
40 words
A process as recited in claim 3, further comprising removing at least a portion of the coal residue from the portion of the catalytic reaction stage effluent used as rich hydrogen-donor solvent before passing the same through said stabilization stage.
Claim 6
Dependent Claim
29 words
A process as recited in claim 4, further comprising adding hydrogen to said stabilization stage to maintain the hydrogen partial pressure in the range of 70 to 700 atmospheres.
Claim 7
Dependent Claim
29 words
A process as recited in claim 3, claim 4 or claim 5, wherein the slurry space velocity in said dissolving stage is in the range 12-120 hr. -1 .
Claim 8
Dependent Claim
17 words
A process as recited in claim 1 wherein said dissolving stage is operated without added molecular hydrogen.
Claim 9
Dependent Claim
24 words
A process as recited in claim 1 wherein said stabilization stage is operated at a temperature lower than the temperature of said dissolving stage.
Claim 10
Dependent Claim
25 words
A process as recited in claim 1 wherein said catalytic reaction stage is operated at a temperature lower than the temperature of said stabilization stage.
Claim 11
Dependent Claim
42 words
A process as recited in claim 1 wherein said stabilization stage is operated at a temperature lower than the temperature of said dissolver stage and said catalytic reaction stage is operated at a temperature lower than the temperature of said stabilization stage.
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) | 1984-04-27 | 1984-10-27 | 1985-04-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-04-27 | 1988-10-27 | 1989-04-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-04-27 | 1992-10-27 | 1993-04-28 | $7700.00 | Window Closed / Lapsed |