US4973386A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passive acoustic power spectra to monitor and control processing
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1988-06-29
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Granted: 1990-11-27
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Expires: 2008-06-29
Abstract
Abstract A process for the detection and measurement of wall coke at a specific location in a fluid bed coker through the measurement of the vibrations of the external shell of the coker at the location.
Inventors
- 👤 Andrew J. Callegari
- 👤 Eugene R. Elzinga, Jr.
- 👤 George D. Cody
- 👤 Roger W. Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:14
CPC Classifications
C; C10; C10B; C10B55/00; C10B55/02; C10B55/04; C10B55/08; C10B55/10; G; G01; G01B; G01B17/00; G01B17/02; G01N; G01N29/00; G01N29/04; G01N29/045; G01N29/046; G01N2291/00; G01N2291/02; G01N2291/028; G01N2291/02827; G01N2291/02854; Y; Y10; Y10S; Y10S208/00; Y10S208/01
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
158 words
A process for the non-intrusive passive acoustic detection and measurement of a change in thickness of a wall defining a reactor for processing material, wherein said change in thickness is due to erosion of said wall or material buildup on said wall using wall vibrations produced by a source within said reactor comprising: (a) measuring the wall vibration of said reactor wall and then determining a first power spectrum indicative of the measured wall vibrations as a function of frequency at a time t=0; (b) operating said reactor for a time, t; (c) measuring the wall vibrations of said reactor wall and then determining a second power spectrum indicative of the measured wall vibrations as a function of frequency at said time, t; (d) determining a frequency shift of a resonance on said first spectrum from the corresponding resonance on said second spectrum, and; (e) correlating said frequency shift with the change in thickness of the reactor wall.
Claim 2
Dependent Claim
158 words
A process for the non-intrusive passive acoustic detection and measurement of a change in thickness of a wall defining a reactor for processing material, wherein said change in thickness is due to erosion of said wall or material buildup on said wall using wall vibrations produced by a source within said reactor comprising: (a) measuring the wall vibration of said reactor wall and then determining a first power spectrum indicative of the measured wall vibrations as a function of frequency at a time t=0; (b) operating said reactor for a time, t; (c) measuring the wall vibrations of said reactor wall and then determining a second power spectrum indicative of the measured wall vibrations as a function of frequency at said time, t; (d) determining a frequency shift of a resonance on said first spectrum from the corresponding resonance on said second spectrum, and; (e) correlating said frequency shift with the change in thickness of the reactor wall.
Claim 3
Dependent Claim
34 words
The process of claim 1 wherein said reactor is a fluid bed coker reactor and said change in thickness of said wall is due to coke buildup on the interior surface of said wall.
Claim 4
Dependent Claim
28 words
The process of claim 1 wherein said steps of measuring said wall vibrations are performed by using an accelerometer attached to the exterior surface of said reactor wall.
Claim 5
Dependent Claim
67 words
The process of claim 1 wherein said step of correlating said frequency shift with the change in thickness of said wall, D i (t), is performed using ##EQU2## where f i (t) is the frequency of said resonance at said time, t, f i (o) is the frequency of said resonance at said time, t=0, and C is the effective compressional sound velocity of said reactor wall.
Claim 6
Dependent Claim
18 words
The process of claim 1 further comprising the step of displaying said change in thickness of said wall.
Claim 7
Dependent Claim
20 words
The process of claim 1 wherein said source for producing said wall vibrations is an open flame within said reactor.
References Cited (Backward Citations)
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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) | 1993-11-26 | 1994-05-28 | 1994-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-11-26 | 1998-05-28 | 1998-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-11-26 | 2002-05-28 | 2002-11-27 | $7700.00 | Window Closed / Lapsed |