US3607738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sewage treatment
Assignee: ChampionX LLC
•
Filing: 1969-02-12
•
Granted: 1971-09-21
•
Expires: 1989-02-12
Abstract
Abstract Sewage treatment in which sewage is passed to a tertiary treatment plant from an activated sludge plant, said tertiary treatment including the step of intimately mixing lime and particular polyamines with the effluent from the secondary clarifier. The polyamines catalyze the reduction of phosphate in the sewage by the lime, thereby lowering the quantity of lime required to produce water having a satisfactory phosphate level.
Inventors
- 👤 Donald A Nelson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:05
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/5236; C02F1/54
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
19 words
A process as claimed in claim 1 wherein said polyamine is the reaction product of ammonia and ethylene dichloride.
Claim 2
Dependent Claim
29 words
A process as in claim 1 wherein the amount of polyamine added to said waste water is from 1 to 40 p.p.m. based on the amount of waste water.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |