Development of a continuous flow paddy dryer with infrared radial radiation technique

Abstract

The objective of this research was to design and development of a continuous flow paddy dryer with infrared radial radiation technique. The prototype of dryer consists of two concentric circular cylinders, cylinders, which the paddy drying chamber is height of 1 m. The inner cylinder has diameter of 26.5 cm made from glasses and outer cylinder has diameter of 29.5 cm made from perforated (1.75 mm) steel sheet. At the center of cylinders installed 1,200 w of electric infrared heater. A hopper was installed on the top of the chamber while 120 w of blower and paddy flow control were installed at bottom of chamber. The performance of the dryer in terms of specific energy consumption (SED), drying rate (DR) and quality of paddy i.e. head rice yield (HRY) and whiteness index (WI) were evaluated by drying 15 kg of paddy with initial moisture content of 23-26% (w.b.) by using the drying conditions of 80oC of drying chamber temperature, 1.075 m3/min of air flow rate and 0.837, 1.228 1.875 and 2.308 kg/min of paddy flow rate. The results found that paddy flow rate at 1.875 kg/min is the optimum condition because gave the highest DR, lowest SEC and rice qualities (HRY and WI) closely to control.