Remediation of Contaminated Soil and Groundwater
Response to the following questions:
1. Soil Venting with Activated Carbon
Soil venting, coupled with granular activated carbon (GAC) for off-gas treatment, is considered as another alternative. The flow rate from soil venting is 100 scfm (2.8 m3/min) and air discharge limit from the off-gas treatment is 0.13 lb TPI-I/day (0.06 kg TPH/day). As part of the preliminary design, estimate the required change-out frequency of GAC adsorbers.
Using the following simplified assumptions in your calculation:
TPH removal efficiency by GAC adsorbers = 98%
one GAC adsorber to be installed (volume of GAC in the adsorber = 70 ft3 = 2 m3)
actual adsorption capacity of GAC = 0.10 lb TPH/lb of GAC = 0.10 kg TPH/kg of GAC
the bulk density of GAC = 30 lb/ft3 = 480 kg/m3
2. Soil Venting with Thermal Processes
A direct incinerator (V = 5 ft3) is also considered to treat the off-gas from soil venting . The local air pollution control regulatory agency requires a minimum residence time of 0.3 second at 1400 °F. Will the incinerator be large enough to meet the requirement?