Aerobic waste sludge digester-thickener orbital system and method
US4940545A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1989 |
| Grant date | Jul 10, 1990 |
| Priority date | — |
| Expiry date | Mar 29, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/926
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A thickener well is provided in one end of a digester orbital ditch having a pair of channels and an elongated center partition spaced from a pair of ditch endwalls, the overall ditch forming a basin for digestion of wasted sludge. A curved endwall of the ditch provides a common curved top outer peripheral wall of the thickener well. The remainder of the well has a cylindrical configuration integral with the orbital ditch bottom and extending downwardly therefrom to a position below the horizontal plane of the ditch bottom. A sludge raking structure is positioned at the bottom of the well for periodically raking settled sludge into a sludge outlet at the bottom of the well. A surface aerator is provided between and spaced from the other ditch endwall and a juxtaposed end of the partition or other aeration apparatus mounted in a channel(s) to aerate and propel a liquid-solids sludge mixture wasted from a secondary treatment apparatus and fed into the orbital ditch. The mixture is circulated in the ditch and across and through a top portion of the well. The orbital ditch may be decanted by turning off the aerator, allowing a clear liquid top layer to form in the ditch and decanting t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.