Design and Construction of the Flat Plate Solar Air Heater For Spray Dryer

The aims of this paper were to study the design and construction of the solar air heater for spray dryer. Incline adjustment of the flat plate solar air heater is variable factors that affects thermal efficiency and appropriateness in collecting the solar. The dimension of solar air heater was 1.20 meter x 1.60 meter x 0.20 meter, which had a black flat plate of galvanized steel with size 3.04 square meters attached below the covered glass for used to as solar air collector. It was found that, the inclination angle of 15 degree had a maximum temperature of 83.92 degree Celsius during 12:00-12:30 hours. At the same time, the hot air transfer to spray dryer was 52.58 degree Celsius, which was the best temperature of all angles. When comparing the electricity consumption before and after the installation of solar air heater, it can reduce power consumption of about 30 kilowatt-hour. In addition when the system is in operation at 5.25 baht per unit, it produces profit of 8,284.9 Baht per year and the payback period was calculated around 34 days.