Question: 4 Soil vapor extraction is a chosen remedy remove volatile organic compounds. The extracted gas stream contains trichloroethylene (TCE) at 0.0016 kg/ms and the extraction gas flow rate is 30 m3/s. The extracted gas need to be treated using granular activated carbon (GAC). From experimental data it was determined that the TCE adsorption capacity to GAC is 550 mg/g. A commercially available single unit of GAC have the following characteristics: i. Gas flow capacity through the GAC unit 4 m s ii. Diameter of the GAC unit 3.5 m ii. Amount of carbon available in each unit 5000 kg b) What is the daily mass of TCE being removed? (5 Points) c) What is the daily mass of GACrequired to remove TCE from the gas stream? (5 Points) d) How frequently will the GAC units require regeneration? (2.5 Points) Solution Flow rate=30 m3/s, gas flow capacity=4 m3/s, dia of GAC=3.5 a)GAC units required=(flowrate/gas flow capacity)/dia of GAC =(30/4)/3.5=2.14=2 units required .

1. Question: 4 Soil vapor extraction is a chosen remedy remove volatile organic compounds. The
extracted gas stream contains trichloroethylene (TCE) at 0.0016 kg/ms and the extraction gas
flow rate is 30 m3/s. The extracted gas need to be treated using granular activated carbon (GAC).
From experimental data it was determined that the TCE adsorption capacity to GAC is 550 mg/g.
A commercially available single unit of GAC have the following characteristics: i. Gas flow
capacity through the GAC unit 4 m s ii. Diameter of the GAC unit 3.5 m ii. Amount of carbon
available in each unit 5000 kg b) What is the daily mass of TCE being removed? (5 Points) c)
What is the daily mass of GACrequired to remove TCE from the gas stream? (5 Points) d) How
frequently will the GAC units require regeneration? (2.5 Points)
Solution
Flow rate=30 m3/s, gas flow capacity=4 m3/s, dia of GAC=3.5
a)GAC units required=(flowrate/gas flow capacity)/dia of GAC
=(30/4)/3.5=2.14=2 units required