US5363693A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery boiler leak detection system and method
Assignee: International Paper Co
•
Filing: 1992-08-19
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Granted: 1994-11-15
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Expires: 2012-08-19
Abstract
Abstract A method for detecting leakage from a chemical recovery boiler system of the type which includes a recovery boiler and associated output steam piping includes the steps of measuring fluid input into the recovery boiler system; measuring fluid output from the recovery boiler system; and calculating fluid leakage loss based on the differences between the measured fluid input and output values.
Inventors
- 👤 Albert A. Nevruz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:49
CPC Classifications
F; F22; F22B; F22B37/00; F22B37/02; F22B37/42; F22B37/421; G; G01; G01M; G01M3/00; G01M3/02; G01M3/26
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
161 words
A method for detecting leakage from a chemical recovery boiler system of the type which includes a recovery boiler and associated output steam piping, comprising steps of: (a) periodically measuring fluid input to a recovery boiler system to obtain data; (b) periodically measuring fluid output from a recovery boiler system to obtain data; (c) periodically calculating short term average drum balances from the data obtained in steps (a) and (b); (d) periodically calculating long term average drum balances from the data obtained in steps (a) and (b); (e) calculating a standard deviation for said short term average drum balances; (f) calculating a standard deviation for said long term average drum balances; (g) using said standard deviation of said short term average drum balances and said long term average drum balances to determine whether a significant difference exists between said short term average and said long term average; and (h) indicating an error condition if a significant difference is determined to exist.
Claim 2
Independent Claim
161 words
A method for detecting leakage from a chemical recovery boiler system of the type which includes a recovery boiler and associated output steam piping, comprising steps of: (a) periodically measuring fluid input to a recovery boiler system to obtain data; (b) periodically measuring fluid output from a recovery boiler system to obtain data; (c) periodically calculating short term average drum balances from the data obtained in steps (a) and (b); (d) periodically calculating long term average drum balances from the data obtained in steps (a) and (b); (e) calculating a standard deviation for said short term average drum balances; (f) calculating a standard deviation for said long term average drum balances; (g) using said standard deviation of said short term average drum balances and said long term average drum balances to determine whether a significant difference exists between said short term average and said long term average; and (h) indicating an error condition if a significant difference is determined to exist.
Claim 3
Dependent Claim
28 words
A method according to claim 1, wherein steps (a) and (b) comprise measuring the rate of fluid mass flow into and, respectively, out of, the recovery boiler system.
Claim 4
Dependent Claim
14 words
A method according to claim 1, wherein said indicating step comprises sounding an alarm.
Claim 5
Dependent Claim
19 words
A method according to claim 1, wherein step (a) comprises measuring feed water flow into the recovery boiler system.
Claim 6
Dependent Claim
19 words
A method according to claim 1, wherein step (a) comprises measuring attemperator fluid flow into the recovery boiler system.
Claim 7
Dependent Claim
20 words
A method according to claim 1, wherein step (b) comprises measuring the flow of steam from the recovery boiler system.
Claim 8
Dependent Claim
21 words
A method according to claim 1, wherein step (b) comprises measuring the flow of blow-down discharges from the recovery boiler system.
Claim 9
Dependent Claim
48 words
A method according to claim 1, wherein step (g) comprises calculating a statistical t test value from said short term average drum balances and said long term average drum balances and said standard deviation of said short term average drum balances and said long term average drum balances.
Claim 10
Independent Claim
177 words
An apparatus for detecting leakage from a chemical recovery boiler system of the type which includes a recovery boiler and associated output steam piping, comprising: means for periodically measuring fluid input to a recovery boiler system to obtain data; means for periodically measuring fluid output from a recovery boiler system to obtain data; means for periodically calculating a short term average drum balances from said data that is obtained by said input and output measuring means; means for periodically calculating a long term average drum balances from the data that is obtained by said input and output measuring means; means for calculating a standard deviation for said short term average drum balances; means for calculating a standard deviation for said long term average drum balances; means for using said standard deviation of said short term average drum balances and said long term average drum balances to determine whether a significant difference exists between said short term average and said long term average; and means for indicating an error condition if a significant difference is determined to exist.
Claim 11
Independent Claim
177 words
An apparatus for detecting leakage from a chemical recovery boiler system of the type which includes a recovery boiler and associated output steam piping, comprising: means for periodically measuring fluid input to a recovery boiler system to obtain data; means for periodically measuring fluid output from a recovery boiler system to obtain data; means for periodically calculating a short term average drum balances from said data that is obtained by said input and output measuring means; means for periodically calculating a long term average drum balances from the data that is obtained by said input and output measuring means; means for calculating a standard deviation for said short term average drum balances; means for calculating a standard deviation for said long term average drum balances; means for using said standard deviation of said short term average drum balances and said long term average drum balances to determine whether a significant difference exists between said short term average and said long term average; and means for indicating an error condition if a significant difference is determined to exist.
Claim 12
Dependent Claim
38 words
An apparatus according to claim 9, wherein said fluid input measuring means and said fluid output measuring means both comprise means for measuring the rate of fluid mass flow into and, respectively, out of, the recovery boiler system.
Claim 13
Dependent Claim
13 words
An apparatus according to claim 9, wherein said indicating means comprises an alarm.
Claim 14
Dependent Claim
26 words
An apparatus according to claim 9, wherein said fluid input measuring means is constructed and arranged to measure feed water flow into the recovery boiler system.
Claim 15
Dependent Claim
26 words
An apparatus according to claim 9, wherein said fluid input measuring means is constructed and arranged to measure attemperator fluid flow into the recovery boiler system.
Claim 16
Dependent Claim
27 words
An apparatus according to claim 9, wherein said fluid output measuring means is constructed and arranged to measure the flow of steam from the recovery boiler system.
Claim 17
Dependent Claim
28 words
An apparatus according to claim 9 wherein said fluid output measuring means is constructed and arranged to measure the flow of blow-down discharges from the recovery boiler system.
Claim 18
Dependent Claim
85 words
An apparatus according to claim 9, wherein said means for using said standard deviation of said short term average drum balances and said long term average drum balances to determine whether a significant difference exists between said short term average and said long term average comprises means for calculating a t test value from said short term average drum balances and said long term average drum balances and said standard deviation of said short term average drum balances and said long term average drum balances.
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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) | 1997-11-14 | 1998-05-16 | 1998-11-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-11-14 | 2002-05-16 | 2002-11-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-11-14 | 2006-05-16 | 2006-11-15 | $7700.00 | Window Closed / Lapsed |