Water treatment
US4131545A · kind A · utility
11Cited by
1References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 2, 1977 |
| Grant date | Dec 26, 1978 |
| Priority date | — |
| Expiry date | May 2, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/907
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Phosphate containing basic aluminum solutions are provided by reaction aluminum sulphate solution with phosphoric acid, adding chloride, basifying by precipitation of calcium sulphate from solution and cooling the resultant solution in a controlled manner. Preferably addition of chloride and basification occurs at a temperature of 80.degree.-90.degree. C and the solution is cooled to below 60.degree. C soon after the basifying salts have been introduced. The solutions, preferably diluted to an aluminum content of 1 to 2% Al.sub.2 O.sub.3 are useful for clarifying water and dewatering sewage sludge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.