US4834778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Determination of slag tap blockage
Assignee: Shell USA Inc
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Filing: 1987-10-26
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Granted: 1989-05-30
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Expires: 2007-10-26
Abstract
Abstract A method and apparatus for determining blockage of a coal gasification slag tap by observing changes in the pressure differential across a diaphragm seal located within an annulus formed by a pressurized vessel and a gasifier contained therewithin.
Inventors
- 👤 Clifford C. Segerstrom
- 👤 Jacob H. Stil
- 👤 Pieter J. Schuurman
- 👤 Gunter K. Eckstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:17
CPC Classifications
C; C10; C10J; C10J3/00; C10J3/46; C10J3/48; C10J3/485; C10J3/72; C10J3/723; C10J2300/00; C10J2300/09; C10J2300/0983; C10J2300/0996; C10J2300/12; C10J2300/1223; Y; Y10; Y10S; Y10S48/00; Y10S48/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
123 words
A method for preventing blockage of the slag tap of a coal gasification reactor contained within a pressure vessel whereby a pressurized annulus is formed between said reactor and said pressure vessel, said method comprising the steps of: dividing and sealing said annulus into an upper pressurized annulus and a lower pressurized annulus, said lower pressurized annulus being in open communication with said reactor downstream of said slag tap; establishing an acceptable operating pressure difference between said upper and said lower annulus; operating said reactor under initial operating conditions; measuring the pressure difference between said upper and lower annulus during operation of said reactor; and changing the operating conditions of said reactor upon said measured pressure difference exceeding said acceptable operating pressure difference.
Claim 2
Independent Claim
123 words
A method for preventing blockage of the slag tap of a coal gasification reactor contained within a pressure vessel whereby a pressurized annulus is formed between said reactor and said pressure vessel, said method comprising the steps of: dividing and sealing said annulus into an upper pressurized annulus and a lower pressurized annulus, said lower pressurized annulus being in open communication with said reactor downstream of said slag tap; establishing an acceptable operating pressure difference between said upper and said lower annulus; operating said reactor under initial operating conditions; measuring the pressure difference between said upper and lower annulus during operation of said reactor; and changing the operating conditions of said reactor upon said measured pressure difference exceeding said acceptable operating pressure difference.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein changing the operating conditions comprises increasing the temperature by adding calcium to the coal mixture.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein changing operating conditions comprises increasing the temperature by changing the weight ratio of oxygen to coal.
References Cited (Backward Citations)
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-05-29 | 1992-11-28 | 1993-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-05-29 | 1996-11-28 | 1997-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-05-29 | 2000-11-28 | 2001-05-30 | $7700.00 | Window Closed / Lapsed |