Volatile Organic Compound Recovery/Recycle

Task Description

This process consists of activated carbon adsorbers located at each extraction well, plus a truck-
mounted Brayton cycle heat pump (BCHP) to regenerate the adsorb-
ers on a periodic basis (Figure 6.2). The VOC-laden air from the well is passed through the carbon bed, adsorbing the VOCs. When the car-
bon bed becomes saturated, hot nitrogen from the regenerator is used to desorb the VOCs. The nitrogen is then passed through a chiller, is compressed, and is then cooled in a recuperator, where 50 to 80% of the organics are remov-
ed. The partially depleted nitrogen stream is then expanded through a

turbine, lowering the temperature down to minus 101°C, to condense the remaining VOCs. The now clean nitrogen passes through the recuperator to cool the incoming VOC-laden nitrogen.

Technology Needs

Many DOE sites as well as private industrial sites have soil and/or groundwater that are contaminat-
ed with organic compounds. These sites will have to undergo remediation in the future. One method of remediation is vapor vacuum extraction, but air quality regulations requires that the ex-
haust be free of organic vapors before they are vented to the at-
mosphere. Therefore, a method of organic vapor recovery or destruc-
tion will be required before vapor