Carbon-based soil cleaning
15 Jan 2000
A remedial technology developed jointly by Xerox and environmental engineering group Dames & Moore will clean contaminated sites.
The standard clean up technique is to suck air over the contaminants, which are then incinerated. But contaminants from, say, an emulsion can block up the processing system. The two companies have developed a 'dual phase' vapour extraction technique, using vacuum and activated carbon and now patented by Xerox.
The companies claim the technique is 'five to ten times more efficient' than other methods for cleaning contaminated groundwater and soil of low water permeability.
A vacuum is applied in the ground at the water table, sucking up the water and carrying it through an air stream, which strips out the volatiles. The air is driven through carbon to rid it of organics, which are incinerated. The water is discharged to the sewer.
