note that:X=432:10^5 kg total moisture/kg dry solid

Question 2 (25 marks) It is desired to dry 498 kg solid/h containing 0.07kg total moisture/kg dry solid to X kg total moisture/kg dry solid (Refer Note Q1). The granular solid enters the dryer at 27 C and leaves at 50C. The heat capacity of the dry solid is 1.465 kJ/kg.K and it is assumed to be constant. The hot air enters the dryer at 90C with absolute humidity of 0.01 kg H2O/kg dry air and leaves the dryer at 38C. Using 0C as a datum and the heat capacity of moisture is 4.187 kJ/kg H2O.K. Assume heat losses of 1.41 kW in the dryer. Draw a schematic diagram of the continuous countercurrent dryer above, detailing all input and output parameters. Then: (a) Calculate the air flow rate. (17 marks) (b) Determine the humidity of the air at the outlet of the dryer. (2 marks) (c) A continuous dryer is often associated with high cost due to the necessity for a heater to produce hot dry air to efficiently dry the solids. Conceptualize a design modification to the continuous countercurrent drying process above that is able to reduce the operational cost. Include in schematic diagrams to support your (6 marks)