Computation of Drying Time for given Critical and Equilibrium Moisture Contents: A commercial drier needed 7 hr to dry a moist material from a moisture content of 33% to one of 9% (bone-dry basis). The critical moisture content of the material was 16%, and the equilibrium moisture content was 5%. Determine the time needed to dry this material from moisture content of 37% to one of 7% if the drying conditions remain unchanged. Neglect the initial starting period.