Wet wood chips are dried in a continuous rotary dryer that operates at atmospheric pressure. The chips enter at 19oC with a water content of 40 wt% and must leave with a moisture content of less than 15%. Hot air is fed to the dryer at a rate of 11.6 m3(STP)/kg wet chips. To monitor the performance of the dryer by sampling the exiting chips and determining their moisture content directly would be a cumbersome procedure and almost impossible to automate. Instead, wet- and dry-bulb thermometers are mounted in both the inlet and outlet air lines, and the moisture content of the exiting chips is determined by a material balance. After the unit goes on-stream, the inlet dry-bulb temperature is found to be 100oC, and the wet-bulb temperature is low enough so that the moisture content of the air may be neglected. The dry-bulb temperature of the exiting air is found to be 38oC, and the wet-bulb temperature is 29oC. (a) Use the psychrometric chart to calculate the absolute humidity (kg H20/kg dry air) and specific enthalpy (kJ/kg dry air) of the outlet air stream. Then calculate the mass of water in the exiting air per kilogram of wet chips fed, assuming dry air has a molecular weight of 29.0. (b) Calculate the moisture content of the emerging chips and determine whether the design specification of less than 15% H2O has been achieved.