Methods and apparatus for treating animal manure
US7156999B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2003 |
| Grant date | Jan 2, 2007 |
| Priority date | — |
| Expiry date | Mar 11, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/37
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A method of treating animal manure yielding a final liquid fraction and solid fractions whereby the final liquid fraction has a suspended solids (SS) content of about 3 g/L or lower comprising subjecting at least a part of said manure to a first biological passive flotation step in a flotation unit having a hydraulic residency time (HRT) of about 4 to about 24 hours with a polymer to yield a first flotation solid fraction and a first flotation liquid fraction, said method comprising a further treatment. An apparatus for treating animal manure comprising a main flotation unit having a HRT of about 4 to about 24 hours, said main flotation units including skimming means for removing floating solids from at least a portion of the surface of the manure and dredging means for removing settled contaminants from at least a portion of the bottom of the tank, whereby at least a part of said manure is directed to the main flotation unit wherein it is separated in a first floating solids fraction, a second liquid fraction and a first settled solids fraction and wherein the second liquid fraction has a SS content of about 3 g/L or lower.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.