Fresh air with a dew point of 290 K is used in an adiabatic dryer which recycles a portion of the wet air. The combined mixture of fresh air and recycled air is passed through a heater which raises its temperature to 365 K before admitted to the dryer. The wet-bulb temperature of the air entering the dryer is 310 K and the air leaving the dryer is 95% saturated. Calculate the following:

(a) The fraction of waste humid air recycled (Ans: 0.2)

(b) The mass of water evaporated from the wet feed per 100 cubic metres of hot air entering the dryer at 101.3 kPa (Ans: 2.25Kg)