Treatment of sewage
US4115258A · kind A · utility
Inventors
Key dates
| Filing date | Jun 22, 1976 |
| Grant date | Sep 19, 1978 |
| Priority date | — |
| Expiry date | Jun 22, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/10
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
Pure oxygen or a gas containing substantially more oxygen than air is injected under pressure into sewage held in or flowing through a rising or pumping sewer. This injection may be used to prevent the concentration of dissolved oxygen in the sewer falling to a level at which there occurs bacterial reduction to hydrogen sulphide of sulphate present in the sewage and/or to reduce the Biochemical Oxygen Demand of the sewage. The injection can also be used to oxidize to sulphur any sulphide dissolved in the sewage. The pure oxygen or the gas containing more oxygen than air may be injected into sewage flowing through a sewage pipe forming part of a rising or pumping sewer, into a pump used to transfer the sewage through the sewer, or into a part of the sewer (e.g. a sump) where sewage is collected before being transferred through the sewer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.