Patent US4400034A successfully refreshed from Google Patents.
US4400034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal comminution and recovery process using gas drying
Assignee: Mobil Oil AS
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Filing: 1981-02-09
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Granted: 1983-08-23
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Expires: 2001-02-09
Abstract
Abstract This invention is a comminution process for treating coal with a drying gas to form fractures which weaken the structure of the coal and make it easier to disintegrate mechanically, chemically or by fluid force. Another aspect of this invention is a process for treating an underground formation of coal with a dry gas for a time sufficient to form cracks and fractures in a portion of the formation in order to increase the permeability of the coal formation to the flow of fluids therethrough. Processes for in-situ combustion of the coal formation are therefore more efficient since the coal formation is more permeable to the flow of gas therethrough.
Inventors
- 👤 Ju-Nam Chew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:33
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243; E21B43/25; E21B43/26; E21B43/2605; E21B43/28
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
75 words
An improved process for comminuting coal wherein the coal is treated with an effective amount of a solvent selected from the group consisting of a basic aqueous solution and methanol, the improvement comprising first contacting said coal with a drying gas and continuing to contact said coal with said drying gas for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal thereby enhancing comminution.
Claim 2
Dependent Claim
75 words
An improved process for comminuting coal wherein the coal is treated with an effective amount of a solvent selected from the group consisting of a basic aqueous solution and methanol, the improvement comprising first contacting said coal with a drying gas and continuing to contact said coal with said drying gas for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal thereby enhancing comminution.
Claim 3
Dependent Claim
27 words
The process of claim 1 wherein said basic aqueous solution is selected from the group consisting of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate and ammonia.
Claim 4
Dependent Claim
27 words
The process of claim 1 wherein said drying gas is selected from the group consisting of air, argon, helium, carbon dioxide, methane, oxygen, oxygen-enriched air and nitrogen.
Claim 5
Dependent Claim
19 words
The process of claim 1 wherein the temperature of said dry gas is between 20° C. and 150° C.
Claim 6
Dependent Claim
64 words
An improved process for comminuting coal wherein the coal is treated with an effective amount of gaseous anhydrous ammonia, the improvement comprising first contacting said coal with a drying gas and continuing to contact said coal with said drying gas for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal thereby enhancing comminution.
Claim 7
Dependent Claim
64 words
An improved process for comminuting coal wherein the coal is treated with an effective amount of gaseous anhydrous ammonia, the improvement comprising first contacting said coal with a drying gas and continuing to contact said coal with said drying gas for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal thereby enhancing comminution.
Claim 8
Dependent Claim
27 words
The process of claim 5 wherein said drying gas is selected from the group consisting of air, argon, helium, carbon dioxide, methane, oxygen, oxygen-enriched air and nitrogen.
Claim 9
Dependent Claim
19 words
The process of claim 5 wherein the temperature of said drying gas is between 20° C. and 150° C.
Claim 10
Dependent Claim
106 words
In a process for recovering subterranean coal which comprises contacting a coal seam in-situ with a basic aqueous solution and maintaining said contact for a time sufficient to fragment at least a portion of said coal, disintegrating said portion to form a slurry, and transporting said slurry to the earth's surface to a storage vessel, the improvement comprising first injecting into the coal seam a drying gas; continuing to inject said dry gas into said coal seam for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal; and withdrawing moistened gas from the coal seam.
Claim 11
Dependent Claim
106 words
In a process for recovering subterranean coal which comprises contacting a coal seam in-situ with a basic aqueous solution and maintaining said contact for a time sufficient to fragment at least a portion of said coal, disintegrating said portion to form a slurry, and transporting said slurry to the earth's surface to a storage vessel, the improvement comprising first injecting into the coal seam a drying gas; continuing to inject said dry gas into said coal seam for a time sufficient to fracture at least a portion of said coal by the absorption of moisture from the coal; and withdrawing moistened gas from the coal seam.
Claim 12
Dependent Claim
27 words
The process of claim 8 wherein said drying gas is selected from the group consisting of air, argon, helium, carbon dioxide, methane, oxygen, oxygen-enriched air and nitrogen.
Claim 13
Dependent Claim
18 words
The process of claim 8 wherein the temperature of said drying is between 20° C. and 150° C.
Claim 14
Dependent Claim
26 words
The process of claim 8 wherein said basic aqueous solution is selected from the group consisting of sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate.
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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) | 1986-08-22 | 1987-02-21 | 1987-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-22 | 1991-02-21 | 1991-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-22 | 1995-02-21 | 1995-08-23 | $7700.00 | Window Closed / Lapsed |