US3772187A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sewage treatment process
Assignee: Individual
•
Filing: 1971-07-14
•
Granted: 1973-11-13
•
Expires: 1991-07-14
Abstract
Abstract Domestic sewage and other polluted waters may be treated under a pressure of 1/2 to 5 atmospheres gauge or more with dissolved oxygen, or air, to supply the BOD. The oxygen-containing gas is drawn into the suction of a feed and recycle pump which agitates the liquid-gas mixture, and increases gas solubilization as it is being compressed. Simultaneously, any solids which are present are comminuted in being pumped to the pressure oxidation tank. The higher than atmospheric pressure increases oxygen solubility, concentration, and hence chemical or biochemical reactivity. Thus, a much smaller residence time and vessel is required, the polluted water is withdrawn and depressurized to atmospheric pressure at which pressure some of the dissolved oxygen and other gases are released due to lower solubility, and vented. Most of the liquid after depressurization is recycled to the influent stream for repressurization and additional oxygen dissolution. The recycle may amount to 2 to 50 times, and some sludge obtained may also be recycled. A water turbine may recover some of the mechanical energy used by the pump. The process may be used by itself or as an adjunct to other processes for treating polluted waters, and also for the oxidation of sludge.
Inventors
- 👤 D Othmer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:31
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/1278; C02F3/1294; C02F3/24; C02F3/26; Y; Y02; Y02W; Y02W10/00; Y02W10/10; Y10; Y10S; Y10S210/00; Y10S210/918
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
15 words
The process according to claim 1, wherein the pressure is between 1/2 and 5 atmospheres.
Claim 2
Dependent Claim
15 words
The process according to claim 1, wherein air is the source of the said oxygen.
Claim 3
Dependent Claim
17 words
The process according to claim 1, wherein the said oxygen is between 90 and 100 percent pure.
Claim 4
Dependent Claim
15 words
The process according to claim 1, wherein the said oxidation is at least partly aerobic.
Claim 5
Dependent Claim
19 words
The process according to claim 1, wherein aerobic bacteria are inactive in said liquid due to high pH thereof.
Claim 6
Dependent Claim
15 words
The process according to claim 1, wherein the said oxidation is at least partly non-aerobic.
Claim 7
Dependent Claim
39 words
The process according to claim 1, wherein the dissolved oxygen oxidizes at least some of the said pollutants in said aqueous liquid in said pressure zone during a residence time of from 10 minutes to 5 hours in total.
Claim 8
Dependent Claim
40 words
The process according to claim 8, wherein said oxygen is added to the suction of a pump which forces said aqueous liquid into said pressure zone, and said pressure zone includes at least part of the body of said pump.
Claim 9
Dependent Claim
33 words
The process according to claim 8, wherein said oxygen is added to the said aqueous liquid after it passes a pump pressurizing it at least to the pressure of the said pressure zone.
Claim 10
Dependent Claim
31 words
The process according to claim 8 wherein said oxygen is added in a ratio of from 1 to 50 ppm to the said aqueous liquid passing to the said pressure zone.
Claim 11
Dependent Claim
73 words
The process according to claim 1, comprising the following steps: a. passing said joint stream with said oxygen added thereto to near the bottom of the liquid in said pressure zone, where the pressure is highest due to hydrostatic head; and b. after at least some of the pollutants in said joint stream have been oxidized, withdrawing a less polluted aqueous liquid from near the surface of the liquid in said pressure zone.
Claim 12
Dependent Claim
68 words
The process according to claim 1 comprising the following steps: a. passing said joint stream with said oxygen added thereto in an open subdivided stream through a gas phase above the liquid phase in said pressure zone; and b. after at least some of the pollutants in said joint stream have been oxidized, withdrawing a less polluted aqueous stream from near the bottom of the said pressure zone.
Claim 13
Dependent Claim
53 words
The process according to claim 1, wherein the said more pure aqueous liquid withdrawn from said pressure zone is recycled back from 2 to 50 times to form the said joint stream with the original influent aqueous liquid which is passing in a continuous stream to be pressurized to enter said pressure zone.
Claim 14
Dependent Claim
43 words
The process according to claim 1 wherein the said depressurization of said more pure aqueous liquid is accomplished so as to recover at least some of the mechanical energy originally used in pressurizing said joint stream to the pressure of the pressure zone.
Claim 15
Dependent Claim
40 words
The process according to claim 1 wherein the said depressurization is accomplished in a water turbine mechanically connected to a pump which forces said liquid into said pressure zone, thus furnishing some part of the energy required by said pump.
Claim 16
Dependent Claim
22 words
The process according to claim 1 wherein at least some part of said more pure liquid is withdrawn from the pressure-depressurizing cycle.
Claim 17
Dependent Claim
47 words
The process according to claim 1 wherein insoluble solids are settled to the bottom of said pressure zone and are removed therefrom, said insoluble solids comprising insoluble pollutants originally present in said original aqueous liquid and those insoluble products of partial oxidation of said pollutants originally present.
Claim 18
Dependent Claim
36 words
The process according to claim 18 wherein coagulating agents are added to and mixed with the said original aqueous liquid to aid in the settling of said insoluble solids to the bottom of said pressure zone.
Claim 19
Dependent Claim
35 words
The process according to claim 18 wherein said liquid in said pressure zone is rising to be removed in a more clarified form; and the insoluble solids are coagulating, flocculating, and settling downwardly in counter-current.
Claim 20
Dependent Claim
39 words
The process according to claim 18 wherein at least a part of said insoluble solids are removed from said pressure zone, and are recycled back to join said continuous stream of said original influent liquid to said pressure zone.
Claim 21
Dependent Claim
38 words
The process according to claim 17 wherein said more pure liquid being withdrawn is passed to and through a sedimentation zone, wherein insoluble solids are settled, said sedimentation zone being at a lower pressure than said pressure zone.
Claim 22
Dependent Claim
36 words
The process according to claim 22 wherein said more pure liquid passing through at least some part of said sedimentation zone is rising, while the insoluble solids are coagulating, flocculating, and settling downwardly in counter-current thereto.
Claim 23
Dependent Claim
33 words
The process according to claim 22, wherein coagulating agents are added to and mixed with said withdrawn liquid passing to said sedimentation zone to aid in the settling of said insoluble solids therein.
Claim 24
Dependent Claim
24 words
The process according to claim 22 wherein a clarified liquid is withdrawn from an upper part of said sedimentation zone at a lower pressure.
Claim 25
Dependent Claim
21 words
The process according to claim 22 wherein said settled insoluble solids are removed from a lower part of said sedimentation zone.
Claim 26
Dependent Claim
29 words
The process according to claim 26 wherein at least some part of said removed insoluble solids are recycled back to said joint stream recycling to the said pressure zone.
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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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |