Treatment process for contaminated waste
US5877393A · kind A · utility
26Cited by
18References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jul 14, 1997 |
| Grant date | Mar 2, 1999 |
| Priority date | — |
| Expiry date | Jul 14, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62D2101/43
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A process for treating contaminated waste to stabilize environmentally harmful heavy metals. The waste is contacted with a mixture of a sulfide, preferably calcium sulfide, an inorganic phosphate, which prevents oxidation of sulfide, and a base that at least includes calcium hydroxide. The process stabilizes harmful, heavy metal materials in the waste but avoids the prior art disadvantage of emitting hydrogen sulfide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.