Question

A solid material containing 12% moisture is dried so that it contains 5% water by blowing fresh warm air mixed with recycled air over the solid in the drier. The inlet fresh air has a humidity of 0.01 kg water/kg dry air, the air from the drier that is recycled has a humidity of 0.1 kg water/kg dry air, and the mixed air to the drier 0.04 kg water/kg dry air. For a feed of 1000 kg solid/h fed to the drier, calculate the following:

(a) The kg/h of dried product (Ans: 926.32 Kg/hr)

(b) The kg of dry air/h in the fresh air (Ans: 74.42 Kg)

(c) The kg of dry air/h in the recycled air (Ans: 37.21 Kg)

Answer 1