Method for treatment of waste sand
US5372650A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1993 |
| Grant date | Dec 13, 1994 |
| Priority date | — |
| Expiry date | Apr 27, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process system is disclosed for the treatment of a waste sand material containing metal contaminants. The waste sand material is the product of sandblasting techniques used to remove paint. The metal contaminants generally include lead, copper, chromium, mercury and cadmium, among other heavy metals. The process particularly provides for the concentration of the lead contaminant in a waste sand that can be economically reclaimed or disposed in an environmentally safe manner. The process also produces a cleaned sand that contains only residual amounts of the metallic contaminants in environmentally acceptable levels. The process provides for the contacting of the waste sand material with a paint decomposer, attrition abrading this sand slurry, size separating the attrition abraded slurry to form a waste sand slurry and a cleaned sand, and removing a portion of the excess water content in the waste sand slurry.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.