EP0466303A2
Expired / Lapsed
EP
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Method and system for continuously monitoring and controlling a process stream for dechlorination residual
Assignee: US Filter Wallace and Tiernan Inc
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Filing: 1991-04-26
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Granted: —
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Expires: 2011-04-26
Abstract
Abstract A method and system for directly monitoring and controlling a continuous process stream 12 for dechlorination residual is provided. A sample stream 18 to which a dechlorination agent has been added to completely eliminate a residual disinfectant, is continuously drawn off. An analyzing agent 36, different from the disinfectant, in an amount in excess of that needed to completely react with the dechlorination residual, is added to the sample stream to leave an unreacted amount of analyzing agent. Sufficient time is provided for the analyzing agent to completely react with the dechlorination residual. Thereafter, the sample stream is continuously analyzed to determine the amount of unreacted analyzing agent remaining in the process sample. Based on the amount of analyzing agent added to the process sample and the amount of unreacted analyzing agent remaining in the sample after reaction, the amount of dechlorination residual is continuously determined. The amount of dechlorination agent 16 added upstream to the process stream is continuously selectively varied using the determined amount of dechlorination residual present in the process sample.
Inventors
- 👤 Albert Van Grouw, Iii
- 👤 Gregory Stockinger
- 👤 Wayne B. Huebner
- 👤 James W. Stannard
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 23:35
CPC Classifications
A; A61; A61L; A61L2/00; A61L2/26; A61L2/28; G; G01; G01N; G01N31/00; G01N31/16; G01N31/166; G01N33/00; G01N33/18; G01N33/182
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
176 words
A method for determining the amount of residual disinfectant removing agent in a continuous process stream to which a disinfectant has been added and said disinfectant removing agent has been added to completely remove residual disinfectant, comprising the steps of: (a) continuously drawing off a sample of said process stream; (b) continuously adding to said sample an analyzing agent different from said disinfectant, in an amount sufficient to completely react with residual disinfectant removing agent and leave an unreacted amount of analyzing agent; (c) allowing sufficient time for the analyzing agent to completely react with residual disinfectant removing agent; (d) continuously analyzing the sample to determine the amount of unreacted analyzing agent remaining in the sample; (e) continuously determining the amount of residual disinfectant removing agent in the sample based on the amount of analyzing agent added and the amount of unreacted analyzing agent remaining in the sample after reaction; and (f) using the determined amount of residual disinfectant removing agent to continuously selectably vary the amount of disinfectant removing agent added to the process stream.
Claim 2
Dependent Claim
11 words
A method according to claim 1, wherein the disinfectant is chlorine.
Claim 3
Dependent Claim
15 words
A method according to claim 1, wherein the residual disinfectant removing agent is sulphur dioxide.
Claim 4
Independent Claim
21 words
A method according to any preceding claim, wherein the analyzing agent is selected from the group consisting of iodine and bromine.
Claim 5
Dependent Claim
12 words
A method according to claim 4, wherein the analyzing agent is iodine.
Claim 6
Dependent Claim
18 words
A method according to claim 5, wherein said iodine is at least partially supplied from an iodine source.
Claim 7
Dependent Claim
13 words
A method according to claim 5, wherein said iodine is a reaction product.
Claim 8
Dependent Claim
29 words
A method according to claim 7, wherein said iodine results from a chemical reaction between an iodate and an iodide when subjected to a pH less than about 9.5.
Claim 9
Independent Claim
171 words
A method for determining the amount of residual dechlorination agent in a continuous process stream to which chlorine has been added and said dechlorination agent has been added to completely remove residual chlorine, comprising the steps of: (a) continuously drawing off a sample of said process stream; (b) continuously adding to said sample an iodine-containing analyzing agent, in an amount sufficient to completely react with residual dechlorination agent, and leave an unreacted amount of the iodine-containing analyzing agent; (c) allowing sufficient time for the iodine-containing analyzing agent to completely react with residual dechlorination agent; (d) continuously analyzing the sample to determine the amount of unreacted iodine-containing analyzing agent remaining in the sample; (e) continuously determining the amount of residual dechlorination agent in the sample based on the amount of iodine-containing analyzing agent added and the amount of unreacted iodine-containing analyzing agent remaining in the sample after reaction; and (f) using the determined amount of residual dechlorination agent to continuously selectably vary the amount of dechlorination agent added to the process stream.
Claim 10
Dependent Claim
16 words
A method according to claim 9, wherein the iodine containing analyzing agent comprises an iodine/iodide solution.
Claim 11
Independent Claim
172 words
A method for determining the amount of residual sulfur dioxide in a continuous process stream to which chlorine has been added and said sulfur dioxide agent has been added to completely remove residual chlorine, comprising the steps of: (a) continuously drawing off a sample of said process stream; (b) continuously adding to said sample an iodine analyzing agent, in an amount sufficient to completely react with the residual sulfur dioxide and leave an unreacted amount of iodine analyzing agent; (c) allowing sufficient time for the iodine analyzing agent to completely react with residual sulfur dioxide; (d) continuously analyzing the sample to determine the amount of unreacted iodine analyzing agent remaining in the sample; (e) continuously determining the amount of residual sulfur dioxide in the sample based on the amount of iodine analyzing agent added and the amount of unreacted iodine analyzing agent remaining in the sample after reaction; and (f) using the determined amount of residual sulfur dioxide to continuously selectably vary the amount of sulfur dioxide added to the process stream.
Claim 12
Independent Claim
124 words
A system for determining the amount of residual disinfectant removing agent in a continuous process stream to which a disinfectant has been added and said disinfectant removing agent has been added to completely remove residual disinfectant, comprising: (a) means for drawing off a sample of said process stream; (b) feed means for adding an analyzing agent different from said disinfectant to said sample; (c) analyzer means for analyzing the sample containing added analyzing agent to determine the amount of residual disinfectant removing agent in said sample; and (d) controller means responsive to the analyzer means and the feed means for continuously selectably varying the amount of disinfectant removing agent added to the process stream based on the determined amount of residual disinfectant removing agent.
Claim 13
Dependent Claim
20 words
A system according to claim 12, further comprising means for purging gas from the analyzing agent added to said sample.
Claim 14
Dependent Claim
26 words
A system according to claim 13, wherein the means for purging gas from the analyzing agent comprises a hyrophobic membrane closely fitted within a sealed container.
Claim 15
Dependent Claim
24 words
A system according to claim 12, 13 or 14, further comprising means for adding the analyzing agent to said sample at a determinable rate.
Claim 16
Independent Claim
33 words
A system according to any of claims 12 to 15, wherein the means for analyzing the sample to determine the amount of unreacted analyzing agent remaining in the sample is an amperometric analyzer.
References Cited (Backward Citations)
No citation records indexed.
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