A hot air dryer handles 1,000 kg/h of wet potato feed with a moisture content of 16% wet basis to reduce the moisture content to 3.8% dry basis. Atmospheric air at 23.9C with a relative humidity of 60% is preheated to a dry bulb temperature of 82.2C. The exhaust air leaves the dryer at 60C.

1. After comparing different drying systems, select the best.

2. Solve the system for drying operations for the key design parameters using mathematical correlations and psychrometric chart.

3. Draw a graph for constant rate and falling rate drying regions.