You have just been assigned to design a thermal oxidizer to treat VOCs from a citrus processing plant in Plant City, FL. The exhaust air from the citrus processing flows at 500 m%/min at 200 °C. To effectively reduce emission of VOCs, the air must be raised to 700 °C and held for 0.8 s. The burner requires ambient air at a mass ratio of 14:1 (air/fuel gas). Assume the heat loss and heat generated from the combustion of VOCs are negligible.

(a) Determine the flow rate of methane needed (in kg/min).

(b) Size the oxidizer (i.e., diameter and length in m), assuming flow velocity in the oxidizer is 20 ft/s (6 m/s).