Calcium reclamation process
US3996133A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 11, 1975 |
| Grant date | Dec 7, 1976 |
| Priority date | — |
| Expiry date | Apr 11, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F11/13
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A process for reclaiming calcium values from the solid residual of incineration or calcination of calcium-bearing sewage and water sludges includes the following steps: classifying the residuals on the basis of their size and density to form two classified streams, the first of which contains relatively larger sized solid particles and has a relatively decreased concentration of calcium and the second of which contains relatively increased concentration of calcium for reuse; then mixing the particles in the first stream with water to form an aqueous solution containing calcium hydroxide; then clarifying the aqueous solution in a settling zone to form a sediment relatively rich in the insoluble inert solids and a decanted stream which is relatively rich in calcium values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.