In situ decontamination of spills and landfills by focussed microwave/radio frequency heating and a closed-loop vapor flushing and vacuum recovery system
US5076727A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1990 |
| Grant date | Dec 31, 1991 |
| Priority date | — |
| Expiry date | Jul 30, 2010 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02B3/06
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Moist, warm, clean air from a vapor treatment system is injected into wells which are screened only at the contaminated depth forcing vapor flow only through the contaminated region. Intermediate the injection wells is an extraction well which is also screened only at the contaminated depth. A vacuum is drawn on the extraction well drawing the flushing vapors from the injection wells and toward the extraction well through the contaminated soil thereby entraining some of the contaminants. The contaminants are preferably non-volatile hydrocarbons such as diesel fuel, aviation and jet fuel, crude oil or pesticides. The contaminated, flushing vapor is then treated and recycled. An MW/RF heating system heats the earth's surface and the contaminated soil, thereby enhancing volatilization of the contaminants and their removal via the vapor flushing system. By screening the wells only through the contaminated zone and controlling the flow of clean, moist, warm air through only the contaminated zone, thereby maintaining the contaminated zone in a moist state, the entire energy of the system is focussed on the contaminated region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.