US4118623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous quality control of mined hard and soft coals
Assignee: Consolidation Coal Co
•
Filing: 1977-03-31
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Granted: 1978-10-03
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Expires: 1997-03-31
Abstract
Abstract A method is provided for determining the shale content of mined coal by monitoring the thorium content of the coal. Thorium content and ash content are shown to be related whereby a direct reading of the thorium will be indicative of the shale content of the coal and the ash content of the coal. The method utilizes the natural radiation of thorium to provide the continuous or selective control of mined coals.
Inventors
- 👤 Walter H. Fertl
- 👤 Preston L. Gant
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:53
CPC Classifications
G; G01; G01V; G01V5/00; G01V5/04; G01V5/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
72 words
A method for the rapid determination of ash content of coal comprising a) determining the ratio of thorium to shale based on background gamma emissions; b) determining the ratio of shale to ash content using standard methods of ash determination; c) correlating (a) and (b) to provide a relationship of background gamma emission to ash content; and (d) thereafter determining ash content by means of surface gamma ray spectroanalysis of thorium content.
Claim 2
Independent Claim
72 words
A method for the rapid determination of ash content of coal comprising a) determining the ratio of thorium to shale based on background gamma emissions; b) determining the ratio of shale to ash content using standard methods of ash determination; c) correlating (a) and (b) to provide a relationship of background gamma emission to ash content; and (d) thereafter determining ash content by means of surface gamma ray spectroanalysis of thorium content.
Claim 3
Dependent Claim
13 words
A method as described in claim 1 wherein said determination is made continuously.
Claim 4
Dependent Claim
17 words
A method as described in claim 2 wherein said determinations are made during the mining of coal.
Claim 5
Dependent Claim
15 words
A method as described in claim 3 wherein said determination is made at conveyer belts.
Claim 6
Dependent Claim
14 words
A method as described in claim 3 wherein said determination is made in pipelines.
Claim 7
Dependent Claim
15 words
A method as described in claim 3 wherein said determination is made in gondola cars.
Claim 8
Dependent Claim
28 words
A method as described in claim 4 wherein said surface gamma ray spectroanalysis is made by an energy proportional detector utilizing a cesium iodide or sodium iodide crystal.
References Cited (Backward Citations)
US3940610A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-02 | 1982-04-03 | 1982-10-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-02 | 1986-04-03 | 1986-10-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-02 | 1990-04-03 | 1990-10-03 | $7700.00 | Window Closed / Lapsed |