Volatile contaminant extraction from subsurface apparatus and method
US5893680A · kind A · utility
Inventors
Key dates
| Filing date | Apr 14, 1997 |
| Grant date | Apr 13, 1999 |
| Priority date | — |
| Expiry date | Apr 14, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB09C1/005
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The present invention is a soil remediation system which uses naturally occurring barometric pressure oscillations to remediate volatile contamination in the vadose zone. By applying a surface seal, a collection plenum and a unidirectional gas relief valve to the soil surface above the contaminant plume, the present invention induces a net upward soil gas velocity in the contaminated soil. The sinusoidal velocity of the soil gas is rectified by the present invention to eliminate or minimize its downward velocity component and allow a normal upward velocity component. The resulting net upward velocity sweeps contaminant vapors from the source, releasing them up to the atmosphere through the gas relief valve in small concentrations. This process is regular and steady, and is accomplished without the use of ground bore holes, off-gas treatment or onsite power. Consequently, it is a low cost remediation system applicable to surface contamination above the vadose zone such as may be found in leaking buried pipes, surface spills, buried waste containers, and shallow landfills.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.