Chapter 6, Problem 6.35P

In the manufacture of an active pharmaceutical ingredient (API), the API goes through a final purification step in which it is crystallized, filtered, and washed. The washed crystals contain 47% water. They are fed to a tunnel dryer and leave the dryer at a rate of 165 kg/h containing 5% adhered moisture. Dry air enters the dryer at 145°F and 1 atm, and the outlet air is at 130°F and 1 atm with a relative humidity of 50%. Calculate the rate (kg/h) at which the API enters the dryer and the volumetric flow rate (ft³/h) of inlet air.