US4584107A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating effluents containing sulfur oxides
Assignee: Sumitomo Metal Mining Co Ltd
•
Filing: 1985-03-21
•
Granted: 1986-04-22
•
Expires: 2005-03-21
Abstract
Abstract A method of treating effluents containing sulfur oxide ions, such as sulfite ions, thiosulfate ions, thionate ions and bisulfite ions, comprises blowing ozone-containing air into the effluent to reduce the COD level in the effluent to 6 mg/l or below, and neutralizing the so treated effluent with an alkali. This method is capable of producing neutral effluents with small equipment and within a short period of time, and the treated effluent will not experience an appreciable drop in the pH even if it is left to stand for a prolonged period.
Inventors
- 👤 Takeo Odaka
- 👤 Hiroichi Miyashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:19
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/72; C02F1/78
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
85 words
A method of treating an effluent containing sulfur oxide ions so that it will be provided with a basic pH that will be maintained over a long period of time, said method comprising the steps of (a) blowing into said effluent a sufficient amount of a mixture of air and ozone that the COD level of said effluent will be reduced to 6 mg/l or below, and (b) adding an alkali to said effluent obtained in step (a) to provide it with a basic pH.
Claim 2
Independent Claim
85 words
A method of treating an effluent containing sulfur oxide ions so that it will be provided with a basic pH that will be maintained over a long period of time, said method comprising the steps of (a) blowing into said effluent a sufficient amount of a mixture of air and ozone that the COD level of said effluent will be reduced to 6 mg/l or below, and (b) adding an alkali to said effluent obtained in step (a) to provide it with a basic pH.
Claim 3
Dependent Claim
22 words
The method as defined in claim 1, wherein in step (a) said COD level is reduced to between 3 and 6 mg/l.
Claim 4
Dependent Claim
26 words
The method as defined in claim 1, wherein said mixture of said air and ozone used in step (a) contains about 0.43 volume % of ozone.
Claim 5
Dependent Claim
17 words
The method as defined in claim 1, wherein said alkali used in step (6) is slaked lime.
Claim 6
Dependent Claim
28 words
The method as defined in claim 1, wherein said sulfur oxide ions are selected from the group consisting of sulfite ions, thiosulfate ions, thionate ions and bisulfite ions.
Claim 7
Independent Claim
98 words
A method of disposing of an effluent containing sulfur oxide ions so that it will be provided with a basic pH that will be maintained over a long period of time, said method comprising the steps of (a) blowing into said effluent a sufficient amount of a mixture of air and ozone that the COD level of said effluent will be reduced to 6 mg/l or below, (b) adding an alkali to said effluent obtained in step (a) to provide it with a basic pH, and (c) discharging said effluent obtained in step (b) into a water course.
Claim 8
Independent Claim
98 words
A method of disposing of an effluent containing sulfur oxide ions so that it will be provided with a basic pH that will be maintained over a long period of time, said method comprising the steps of (a) blowing into said effluent a sufficient amount of a mixture of air and ozone that the COD level of said effluent will be reduced to 6 mg/l or below, (b) adding an alkali to said effluent obtained in step (a) to provide it with a basic pH, and (c) discharging said effluent obtained in step (b) into a water course.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-21 | 1989-10-21 | 1990-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-21 | 1993-10-21 | 1994-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-21 | 1997-10-21 | 1998-04-22 | $7700.00 | Window Closed / Lapsed |