US3760829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic control system for the safe and economical removal of nh3 by breakpoint chlorination
Assignee: Environmental Protection Agency
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Filing: 1972-05-09
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Granted: 1973-09-25
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Expires: 1992-05-09
Abstract
Abstract An automatic system for controlling the chlorine feed in the breakpoint chlorination process at the optimum dose level, under the conditions of varying ammonia concentration and process flow rates as well as other fluctuations in process chlorine demand. The function of the automatic breakpoint controller is described by the equation:
Inventors
- 👤 D Bishop
- 👤 W Schuk
- 👤 T Pressley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:09
CPC Classifications
G; G05; G05D; G05D21/00; G05D21/02; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/903; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2499; Y10T137/2509
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
183 words
In an apparatus in accordance with claim 1, the improvement further including: pH analyzer means connected to said effluent line for determining the pH of said effluent and providing an output signal corresponding thereto; pH error signal generating means connected to the output of said pH analyzer means for comparing the measured pH of the effluent with the predetermined optimum pH in the effluent and generating a pH error signal corresponding to the error therebetween; pH controller means connected to the output of said pH error signal generating means and said breakpoint control means for determining the precise amount of base to be added to the wastewater to achieve a predetermined optimum process pH as a function of the amount of chlorine being added by said chlorine control means and said pH error signal, and providing an output signal corresponding thereto; and base control means connected to said base influent line and connected to the output of said pH controller means for causing base to be added to said mixer-reactor in an amount proportionate to the output signal from said pH controller means.
Claim 2
Dependent Claim
110 words
In an apparatus in accordance with claim 1, further comprising a second mixer-reactor in said wastewater influent line before said mixer-reactor, and a chlorine predose line entering into said second mixer-reactor for neutralizing the alkalinity of the wastewater influent, said improvement further comprising: predose control means connected to said chlorine predose line and to said breakpoint control means for controlling the amount of chlorine added to said second mixer reactor and generating a signal corresponding thereto; and wherein said breakpoint controller means further functions to subtract the amount of chlorine dispensed by said predose control means from the determined chlorine amount prior to said correction by the chlorine error signal.
Claim 3
Dependent Claim
15 words
In an apparatus in accordance with claim 1 wherein said breakpoint controller means functions electronically.
Claim 4
Dependent Claim
15 words
In an apparatus in accordance with claim 1 wherein said breakpoint control means functions pneumatically.
References Cited (Backward Citations)
US3528545A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |