Emancipative waste activated sludge stripping to remove internal phosphorus (“eWASSTRIP”)
US10604433B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2018 |
| Grant date | Mar 31, 2020 |
| Priority date | — |
| Expiry date | Oct 24, 2038 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2301/08
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A method of treating a mixture of microorganisms containing phosphorus and magnesium, by first inducing the mixture microorganisms to release phosphorus and magnesium. Next an emancipation or elutriation is performed. Phosphorus and magnesium-rich liquid is then tapped off as the mixture is thickened, to produce phosphorus and magnesium-rich liquid and phosphorus and magnesium-reduced treated mixture. This treated mixture is placed in an anaerobic digester where ammonia is formed but combines very little with phosphorus or magnesium as these elements have been reduced in concentration. Then the high-ammonia mixture is dewatered, to produce an ammonia-rich liquid, which is combined with the phosphorus and magnesium-rich liquid. In one preferred example a useable struvite product is harvested from this combination. Additionally, the production of nuisance struvite in the anaerobic digester is reduced, in comparison with prior art waste treatment methods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.