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USRE29969E Expired / Lapsed US ⏱️ 0.0 years remaining

Treatment of wastewater

Assignee: Siemens Water Technologies Holding Corp
•
Filing: 1977-03-01
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Granted: 1979-04-17
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Expires: 1997-03-01
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Abstract

Abstract Process and apparatus for the oxidation of carbonaceous and nitrogeneous matter in wastewater by use of a mixture of biologically active slimes attached to partially submerged rotating contactors. The biological contactors are mounted in a single-stage treatment unit and are supplied with wastewater at a controlled rate relative to the surface of the contactors and distributed substantially evenly over the contactor surface. A denitrifying unit, located upstream from the single-stage treatment unit is supplied with wastewater and recirculated effluent from the single-stage treatment unit. The denitrifying unit utilizes biologically active slimes attached to rotating biological contactors for the removal of carbonaceous matter from the wastewater supported by nitrate oxygen from the recirculated effluent.

Inventors

  • 👤 Wilbur N. Torpey

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 21:36
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/08; C02F3/082; C02F3/30; C02F3/301; C02F3/302; Y; Y02; Y02W; Y02W10/00; Y02W10/10

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 175 words
A method for treating wastewater containing carbonaceous pollutants measured as BOD 5 and ammonia nitrogen in a weight ratio of at least 3.6:1 respectively, comprising the steps of supplying said wastewater at a predetermined rate to a .Iadd.single stage .Iaddend.biological treatment unit that includes .[.not more than a single.]. .Iadd.at least one .Iaddend.rotatable shaft supporting a plurality of partially submerged biological contactors having surface area for the growth and maintenance of organisms, creating a flow of said wastewater through said biological treatment unit in a direction generally perpendicular to said rotatable shaft .Iadd.so as to feed the organisms on said contactor surfaces substantially equally, .Iaddend.and rotating said shaft to impart a predetermined peripheral velocity to said biological contactors to alternately expose said surface area to wastewater and an oxygen containing atmosphere, said predetermined rate and peripheral velocity being chosen to simultaneously oxidize at least about 83 weight percent of said carbonaceous pollutants measured as BOD 5 and at least about 46 weight percent of said ammonia nitrogen on the same surface area of said contactors.
Claim 2
Independent Claim 175 words
A method for treating wastewater containing carbonaceous pollutants measured as BOD 5 and ammonia nitrogen in a weight ratio of at least 3.6:1 respectively, comprising the steps of supplying said wastewater at a predetermined rate to a .Iadd.single stage .Iaddend.biological treatment unit that includes .[.not more than a single.]. .Iadd.at least one .Iaddend.rotatable shaft supporting a plurality of partially submerged biological contactors having surface area for the growth and maintenance of organisms, creating a flow of said wastewater through said biological treatment unit in a direction generally perpendicular to said rotatable shaft .Iadd.so as to feed the organisms on said contactor surfaces substantially equally, .Iaddend.and rotating said shaft to impart a predetermined peripheral velocity to said biological contactors to alternately expose said surface area to wastewater and an oxygen containing atmosphere, said predetermined rate and peripheral velocity being chosen to simultaneously oxidize at least about 83 weight percent of said carbonaceous pollutants measured as BOD 5 and at least about 46 weight percent of said ammonia nitrogen on the same surface area of said contactors.
Claim 3
Dependent Claim 40 words
The method of claim 1 wherein said oxygen containing atmosphere comprises from 30 to 60 percent oxygen by volume and said predetermined rate is from 1 to .Badd..[. 25.]..Baddend. .Iadd.2.5 .Iaddend.gallons per day per square foot of said surface area.
Claim 4
Dependent Claim 34 words
The method of claim 1 wherein said predetermined rate is from 0.4 to 1.5 gallons per day per square foot of said surface area and said peripheral velocity is from 0.25 to 1.0 ft/sec.
Claim 5
Dependent Claim 27 words
The method according to claim 1 wherein said predetermined rate is from about 0.4 to about 2.5 gallons per day per square foot of said surface area.
Claim 6
Dependent Claim 16 words
The method according to claim 4 wherein the wastewater temperature is greater than about 60° F.
Claim 7
Independent Claim 188 words
A method for treating wastewater containing carbonaceous pollutants measured as BOD 5 and ammonia nitrogen in a weight ratio of at least about 3.6:1 respectively, comprising the steps of supplying said wastewater at a predetermined rate to a .Iadd.single stage .Iaddend.biological treatment unit that includes .[.not more than a single.]. .Iadd.at least one .Iaddend.rotatable shaft supporting a plurality of partially submerged biological contactors having surface area for the growth and maintenance of organisms, creating a flow of said wastewater through said biological treatment unit in a direction generally perpendicular to said rotatable shaft .Iadd.so as to feed the organisms on said contactor surfaces substantially equally, .Iaddend.and rotating said shaft to impart a predetermined peripheral velocity to said biological contactors to alternately expose said surface area to wastewater and an oxygen containing atmosphere, said predetermined rate being from 0.4 to 1.5 gallons per day per square foot of said surface area, whereby the same surface area of said contactors is used to simultaneously oxidize at least about 83 weight percent of said carbonaceous pollutants measured as BOD 5 and at least about 46 weight percent of said ammonia nitrogen.
Claim 8
Independent Claim 188 words
A method for treating wastewater containing carbonaceous pollutants measured as BOD 5 and ammonia nitrogen in a weight ratio of at least about 3.6:1 respectively, comprising the steps of supplying said wastewater at a predetermined rate to a .Iadd.single stage .Iaddend.biological treatment unit that includes .[.not more than a single.]. .Iadd.at least one .Iaddend.rotatable shaft supporting a plurality of partially submerged biological contactors having surface area for the growth and maintenance of organisms, creating a flow of said wastewater through said biological treatment unit in a direction generally perpendicular to said rotatable shaft .Iadd.so as to feed the organisms on said contactor surfaces substantially equally, .Iaddend.and rotating said shaft to impart a predetermined peripheral velocity to said biological contactors to alternately expose said surface area to wastewater and an oxygen containing atmosphere, said predetermined rate being from 0.4 to 1.5 gallons per day per square foot of said surface area, whereby the same surface area of said contactors is used to simultaneously oxidize at least about 83 weight percent of said carbonaceous pollutants measured as BOD 5 and at least about 46 weight percent of said ammonia nitrogen.
Claim 9
Dependent Claim 16 words
The method according to claim 6 wherein said peripheral velocity is from 0.25 to 1.0 ft/sec.
Claim 10
Dependent Claim 31 words
The method according to claim 6 wherein said wastewater contains at least about 109 milligrams per liter of BOD 5 and at least about 25 milligrams per liter of ammonia nitrogen.

References Cited (Backward Citations)

US3266786A Cited
US3335081A Cited
US3596767A Cited
US3547815A Cited
US3557954A Cited
US3704783A Cited
US3654147A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-04-16 1982-10-16 1983-04-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-04-16 1986-10-16 1987-04-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-04-16 1990-10-16 1991-04-17 $7700.00 Window Closed / Lapsed

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