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US3900394A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for total sewage treatment

Assignee: Activox Inc
•
Filing: 1974-05-16
•
Granted: 1975-08-19
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Expires: 1994-05-16
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Abstract

Abstract An improved process for the purification and denitrification of sewage which comprises setting the sewage liquid in motion, aerating the sewage liquid to effect the aerobic decomposition thereof, allowing said aerobic decomposition to continue until substantially the entire oxygen content of said aerated sewage liquid has been depleted, adding additional untreated sewage liquid thereto for the purpose of denitrifying the aerated sewage liquid, and withdrawing said aerated, denitrified sewage liquid for clarification and/or sedimentation and/or recycle; and an apparatus directed thereto which comprises an aeration reservoir fitted with inlet means, agitating means and outlet means, said inlet means being positioned in said reservoir to allow for maximum aerobic decomposition and denitrification.

Inventors

  • 👤 Paul I Rongved

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 14:34
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/1236; C02F3/1257; C02F3/30; C02F3/301; C02F3/302; Y; Y02; Y02W; Y02W10/00; Y02W10/10; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/906; Y10S210/918; Y10S210/926

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 217 words
A CONTINUOUS ACTIVATED SLUDGE SEWAGE TREATMENT PROCESS COMPRISING, IN CONTINUOUS MANNER, INJECTING RAW SEWAGE LIQUID INTO A RESFERVOIR PROVIDING A SINGLE HORIZONTAL CLOSED LOOP PATH, CIRCULATING THE LIQUID AROUND SAID PATH AT A SPEED OF AT LEAST ABOUT 0.8 FEET PER SECOND AND SUFFICIENT TO AVOID SUBSTANTIAL SETTING OF SLUDGE SUSPENDED THEREIN, AERATING THE LIQUID IN SAID PATH TO PROMOTE AEROBIC DECOMPOSITION OF THE SEWAGE AND FORMATION OF NITRATE COMPOUNDS IN SAID LIQUID, CIRCULATING THE AERATED LIQUID AROUND SAID PATH FOR A FIRST DISTANCE IN WHICH SAID DECOMPOSITION PROCEEDS UNTIL THE LIQUID IS SUBSTANTAALLY DEVOID OF OXYGEN AT THE POINT OF RAW SEWAGE INJUCTION, CIRCULATING THE LOQUID CONTAINING NITRATE COMPOUNDS AND RAW SEWAGE AROUND SAID PATH FOR A SECOND DISTANCE IN WHICH DENTRIFICATION PROCEEDS IN SAID LIQUID UNTIL IT REACHES THE NEXT POINT OF AERATION IN SAID PATH, CONTINUOUSLY REMOVING TREATED LIQUID, FOR CLARIFICATION AND SETTLING OF SLUDGE THEREIN, AT A RATE APPROXIMATING THE RATE OF INJECTION OF THE RAW SEWAGE LIQUID, DISCHARGING THE RESULTING CLARIFIED LIQUID EFFLUENT AND RETURNING AT LEAST A PORTION OF THE SETTLED SLUDGE TO THE LIQUID IN SAID RESERVOIR, THE AVERAGE RETENTION TIME OF THE LIQUID IN THE RESERVOIR BEING AT LEAST ABOUT 24 HOURS, SAID SECOND DISTANCE BEING AT LEAST ABOUT 10% OF THE SUM OF SAID FIRST AND SECOND DISTANCES.
Claim 2
Dependent Claim 217 words
A CONTINUOUS ACTIVATED SLUDGE SEWAGE TREATMENT PROCESS COMPRISING, IN CONTINUOUS MANNER, INJECTING RAW SEWAGE LIQUID INTO A RESFERVOIR PROVIDING A SINGLE HORIZONTAL CLOSED LOOP PATH, CIRCULATING THE LIQUID AROUND SAID PATH AT A SPEED OF AT LEAST ABOUT 0.8 FEET PER SECOND AND SUFFICIENT TO AVOID SUBSTANTIAL SETTING OF SLUDGE SUSPENDED THEREIN, AERATING THE LIQUID IN SAID PATH TO PROMOTE AEROBIC DECOMPOSITION OF THE SEWAGE AND FORMATION OF NITRATE COMPOUNDS IN SAID LIQUID, CIRCULATING THE AERATED LIQUID AROUND SAID PATH FOR A FIRST DISTANCE IN WHICH SAID DECOMPOSITION PROCEEDS UNTIL THE LIQUID IS SUBSTANTAALLY DEVOID OF OXYGEN AT THE POINT OF RAW SEWAGE INJUCTION, CIRCULATING THE LOQUID CONTAINING NITRATE COMPOUNDS AND RAW SEWAGE AROUND SAID PATH FOR A SECOND DISTANCE IN WHICH DENTRIFICATION PROCEEDS IN SAID LIQUID UNTIL IT REACHES THE NEXT POINT OF AERATION IN SAID PATH, CONTINUOUSLY REMOVING TREATED LIQUID, FOR CLARIFICATION AND SETTLING OF SLUDGE THEREIN, AT A RATE APPROXIMATING THE RATE OF INJECTION OF THE RAW SEWAGE LIQUID, DISCHARGING THE RESULTING CLARIFIED LIQUID EFFLUENT AND RETURNING AT LEAST A PORTION OF THE SETTLED SLUDGE TO THE LIQUID IN SAID RESERVOIR, THE AVERAGE RETENTION TIME OF THE LIQUID IN THE RESERVOIR BEING AT LEAST ABOUT 24 HOURS, SAID SECOND DISTANCE BEING AT LEAST ABOUT 10% OF THE SUM OF SAID FIRST AND SECOND DISTANCES.
Claim 3
Dependent Claim 24 words
The process of claim 1 wherein the raw sewage liquid is injected into the reservoir in the direction of flow of the liquid therein.

References Cited (Backward Citations)

US3485750A Cited
US3579439A Cited
US3654147A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-08-18 1979-02-17 1979-08-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-08-18 1983-02-17 1983-08-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-08-18 1987-02-17 1987-08-19 $7700.00 Window Closed / Lapsed

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