Process for the purification of sewage while recapturing the fatty and albuminous matter in reusable form
US4208282A · kind A · utility
Inventor
Key dates
| Filing date | Oct 20, 1978 |
| Grant date | Jun 17, 1980 |
| Priority date | — |
| Expiry date | Oct 20, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S530/859
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
There is disclosed a process for the purification of sewage containing fatty and albuminous matter. Raw sewage, which is optionally subjected to primary settling in a primary settling tank, is adjusted so that the pH is approximately the same as the isoelectric point of the main components of the proteins present in the sewage. The sewage is then mixed with an aqueous solution of a substituted anionic starch to precipitate the fatty and albuminous matter by flocculation. Following a short dwell time period, the sewage is subjected to an expansion flotation under a dispersion pressure of 4.5-6 bar. The flotation sludge is separated and a clarified effluent is obtained. The flotation sludge is sterilized by treatment with ultraviolet radiation and the clarified effluent is passed to waste.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.