Question

water reservoir 10 meters deep was found to be contaminated with Chloro-
Tox, a toxic chemical with a dimensionless air/water partition coefficient value of H=50. The
concentration of Chloro-Tox in the water phase was measured to be 50 ppm (note: 1 ppm is
approximately equal to 1 mg/L). At a wind speed of 3 cm/hr (over the water surface), the
average gas-side mass transfer coefficient (over the surface of the reservoir) is 5 m/s and
the liquid-side mass transfer coefficient is 1000 cm/hr.
(a) Determine the concentration of Chloro-Tox at the interface (both from the gas side
and the liquid side) when the bulk gas phase concentration is 50 ppm.
(b) Determine the fractional resistances of the liquid and gas phases to mass transfer.
(c) How long will it take for the concentration of Chloro-Tox to decrease to 25 ppm?

Answer 1