Method of removing phosphorus from sludge
US6620396B2 · kind B2 · utility
1Cited by
9References
20Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 17, 2001 |
| Grant date | Sep 16, 2003 |
| Priority date | — |
| Expiry date | Apr 16, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/906
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A method of recovering elementary phosphorus from an aqueous sludge containing about 1 to about 15 wt % dispersed particles of phosphorus is disclosed. To the sludge is added about 1 to about 20 wt %, based on the weight of the phosphorus present in said sludge, of a phosphate salt that has the general formula: where R is an alkali metal or ammonium and n is 0 to 30. The phosphorus in the sludge is melted and the solids in the sludge are separated from liquid phosphorus and water. Liquid phosphorus is then separated from the water.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.