Method for removing mercury from contaminated soils and industrial wastes and related apparatus
US5300137A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 1992 |
| Grant date | Apr 5, 1994 |
| Priority date | — |
| Expiry date | Sep 18, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF23J2215/60
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A method and an apparatus for removing mercury from contaminated soils and industrial wastes are provided. The removed mercury may be recovered. A furnace vaporizes the mercury containing portion and the vapors are condensed. In one embodiment, an individual heating stage volatilizes water vapor and other volatile contaminants, such as hydrocarbons, with substantial vaporization of the mercury-containing portion, subsequently, a second temperature higher than the first is employed to vaporize the mercury containing portion. In one embodiment, a metallic salt reacts with sulfur in the material to form a stable solid sulfur compound to reduce sulfur content in the gaseous effluent. The addition of a metallic salt may also be employed to react with mercury halides to release elemental mercury therefrom. The contaminated material is thereby converted from one which is hazardous due to mercury contamination to one which is non-hazardous. The effluent is treated to reduce environmental hazards in the same. The system is preferably provided on or in a vehicle so as to facilitate treatment of the contaminated materials at the site of the same.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.