Method of detoxification and stabilization of soils contaminated with chromium ore waste
US5304710A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1993 |
| Grant date | Apr 19, 1994 |
| Priority date | — |
| Expiry date | Feb 18, 2013 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62D2203/10
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method for treating chromium ore waste contaminated soils by detoxification, fixation, immobilization and stabilization comprising the steps of soil grinding, pre-activating, reducing chromium valiancy, forming insoluble metal hydroxides, and incapsulating the chromium compounds containing agglomerates to prevent potential chromium leaching from the soil according with the standard toxicity characteristic leaching procedure requirements. Additive agents such as an acidic solution, a bivalent iron sulfur containing salt, e.g. ferrous sulfate, an alkalifying agent, e.g. calcium lime slurry or lime kiln dust or caustic, a stabilizing agent, e.g. cement, cement kiln dust, silicates, polyelectrolytes, and the like are also disclosed as assisting in the chromium immobilization reactions by reacting with certain constituents in the soil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.