US5565619A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Methods and apparatus for monitoring water process equipment
Assignee: Veolia WTS USA Inc
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Filing: 1994-11-14
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Granted: 1996-10-15
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Expires: 2014-11-14
Abstract
Abstract Methods and apparatus are provided for using tracers to monitor industrial process equipment to which liquid is added and from which liquid is removed. In preferred embodiments, the methods are directed to detecting water leakage in a boiler in which an aqueous temperature control liquid is supplemented with feedwater at a known or unknown rate and is removed as blowdown at a known rate. The methods include determining the blowdown removal rate, adding a tracer to the temperature control liquid at a rate that is directly proportional to the blowdown removal rate, analyzing the blowdown to determine the measured concentration of tracer contained therein, deriving an expected concentration of tracer in the blowdown, and comparing the measured and expected concentrations to detect excessive variance between them.
Inventors
- 👤 Eric Thungstrom
- 👤 Paul R. Burgmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 17:25
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; G01M3/22; G01M3/226; G01M3/228; Y; Y10; Y10T; Y10T436/00; Y10T436/12; Y10T436/13
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
124 words
A method for monitoring a boiler in which a temperature control liquid in a containment means is supplemented with feedwater and is removed as blowdown, said method comprising the steps of: monitoring a rate associated with said blowdown removal; deriving a rate for adding a tracer to said temperature control liquid based on said monitored blowdown removal rate; adding said tracer to said temperature control liquid at said tracer addition rate; determining a measured concentration of said tracer in said blowdown; deriving an expected concentration of said tracer in said blowdown based on said rate of tracer addition to said temperature control liquid; and comparing said measured tracer concentration with said expected tracer concentration to detect variance therebetween indicative of leakage in said boiler.
Claim 2
Independent Claim
124 words
A method for monitoring a boiler in which a temperature control liquid in a containment means is supplemented with feedwater and is removed as blowdown, said method comprising the steps of: monitoring a rate associated with said blowdown removal; deriving a rate for adding a tracer to said temperature control liquid based on said monitored blowdown removal rate; adding said tracer to said temperature control liquid at said tracer addition rate; determining a measured concentration of said tracer in said blowdown; deriving an expected concentration of said tracer in said blowdown based on said rate of tracer addition to said temperature control liquid; and comparing said measured tracer concentration with said expected tracer concentration to detect variance therebetween indicative of leakage in said boiler.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein said tracer is a transition metal compound.
Claim 4
Dependent Claim
12 words
The method of claim 1 wherein said tracer is a molybdenum-containing compound.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein said tracer is a molybdenum salt.
Claim 6
Dependent Claim
11 words
The method of claim 1 wherein said tracer is sodium molybdate.
Claim 7
Dependent Claim
16 words
The method of claim 1 wherein said tracer is an iodide-, lithium-, or phosphate-containing chemical treatment.
Claim 8
Dependent Claim
21 words
The method of claim 1 wherein determining said measured tracer concentration comprises detecting a property of the tracer in said blowdown.
Claim 9
Dependent Claim
26 words
The method of claim 1 wherein determining said measured tracer concentration comprises comparing said blowdown with a standard solution containing a known concentration of said tracer.
Claim 10
Dependent Claim
20 words
The method of claim 8 wherein said comparison is performed visually or using electrochemistry, UV/visible spectrophotometry, or fluorescence emission spectroscopy.
Claim 11
Dependent Claim
14 words
The method of claim 1 wherein said blowdown is continuously monitored for tracer concentration.
Claim 12
Dependent Claim
10 words
The method of claim 1 wherein said blowdown is sampled.
Claim 13
Dependent Claim
18 words
The method of claim 11 wherein a series of samples of said blowdown are taken at regular intervals.
Claim 14
Dependent Claim
18 words
The method of claim 11 wherein a series of samples of said blowdown are taken at irregular intervals.
Claim 15
Dependent Claim
72 words
The method of claim 11 wherein determining said measured tracer concentration in said sample comprises: mixing said sample with a reagent that reacts with said tracer and imparts a color to said sample in proportion to the concentration of tracer in said sample; detecting said sample color; and comparing said sample color with one or more colored standard solutions prepared by mixing solutions containing known concentrations of said tracer with said reagent.
Claim 16
Dependent Claim
13 words
The method of claim 14 wherein said color is detected using UV/visible spectrophotometry.
Claim 17
Dependent Claim
14 words
The method of claim 1 wherein said tracer is added as a tracer-containing solution.
Claim 18
Dependent Claim
60 words
The method of claim 16 wherein said expected concentration of tracer in said blowdown is derived according to the formula: C.sub.E =C.sub.S ·S/B where: C E is the expected equilibrium tracer concentration; C S is the concentration of tracer in said tracer-containing solution; S is the rate of addition of said tracer-containing solution; and B is the blowdown removal rate.
Claim 19
Dependent Claim
109 words
The method of claim 16 wherein said expected concentration of tracer in said blowdown is derived according to the formula: C.sub.E(i) =C.sub.T -[(C.sub.T -C.sub.(i-dt))(e.sup.-Bdt/M)] where C E (i) is the expected concentration of tracer in said blowdown at time i; C T is a tracer concentration setpoint, calculated as (C S ·S/B); C S is the concentration of tracer in said tracer-containing solution; S is the rate of addition of said tracer-containing solution; B is the blowdown removal rate; dt is an elapsed time interval; M is the mass of said temperature control liquid; and C.sub.(i-dt) is a measured value for tracer concentration in the blowdown at time i-dt.
Claim 20
Dependent Claim
27 words
The method of claim 1 wherein comparing said measured tracer concentration with said expected tracer concentration comprises subtracting said measured tracer concentration from said expected tracer concentration.
Claim 21
Dependent Claim
18 words
The method of claim 1 wherein said tracer controls corrosion or deposition of scale in said containment means.
Claim 22
Dependent Claim
31 words
The method of claim 1 further comprising adding a treating agent to said temperature control liquid in an amount effective to control corrosion or deposition of scale in said containment means.
Claim 23
Dependent Claim
25 words
The method of claim 1 further comprising physically analyzing said system in response to variance between said measured tracer concentration and said expected tracer concentration.
Claim 24
Dependent Claim
15 words
The method of claim 1 further comprising monitoring a rate associated with said feedwater supplementation.
Claim 25
Independent Claim
153 words
A system for monitoring a boiler in which a temperature control liquid in a containment means is supplemented with feedwater and is removed as blowdown, said system comprising: monitoring means in communication with said containment means for monitoring a rate associated with said blowdown removal; rate derivation means in communication with said monitoring means for deriving a rate for adding a tracer to said temperature control liquid; addition means in communication with said containment means and said rate derivation means for adding an amount of tracer to said containment means at said tracer addition rate; measuring means in communication with said addition means for measuring a concentration of said tracer in said blowdown; concentration derivation means in communication with said measuring means for deriving an expected concentration of tracer in said blowdown; and comparison means in communication with said concentration derivation means for comparing said measured tracer concentration with said expected tracer concentration.
Claim 26
Independent Claim
153 words
A system for monitoring a boiler in which a temperature control liquid in a containment means is supplemented with feedwater and is removed as blowdown, said system comprising: monitoring means in communication with said containment means for monitoring a rate associated with said blowdown removal; rate derivation means in communication with said monitoring means for deriving a rate for adding a tracer to said temperature control liquid; addition means in communication with said containment means and said rate derivation means for adding an amount of tracer to said containment means at said tracer addition rate; measuring means in communication with said addition means for measuring a concentration of said tracer in said blowdown; concentration derivation means in communication with said measuring means for deriving an expected concentration of tracer in said blowdown; and comparison means in communication with said concentration derivation means for comparing said measured tracer concentration with said expected tracer concentration.
Claim 27
Dependent Claim
22 words
The system of claim 24 wherein said addition means comprises a tracer source-coupled with a flow measurement apparatus and a feed line.
Claim 28
Dependent Claim
13 words
The system of claim 24 wherein said measuring means comprises a UV/visible spectrophotometer.
Claim 29
Dependent Claim
21 words
The system of claim 24 wherein said derivation means comprises processing means coupled with said addition means and said determination means.
Claim 30
Dependent Claim
17 words
The system of claim 24 wherein said comparison means comprises processing means coupled with said derivation means.
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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) | 1999-10-15 | 2000-04-15 | 2000-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-15 | 2004-04-15 | 2004-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-15 | 2008-04-15 | 2008-10-15 | $7700.00 | Window Closed / Lapsed |