DESIGN AND DEVELOPMENT OF SOLAR DRYER

Abstract

The design and construction of a solar dryer, the dryer is composed of solar panel, aircollector and heater, and a solar drying chamber. The air allowed in through air inlet is heated up in the aircollector and channeled through aluminum pipe to the drying chamber where it is utilized in removing the moisture content from the food substances loaded. The dimensions of the dryer are 94cm x 45cm x 101cm/ 20cm (length x width x height). Locally available materials were used for the construction, chiefly comprising of plywood, toughened glass. The optimum temperature of the dryer was 60.5oC with a corresponding ambient temperature of 34.50oC. The mass of water removal of 199.9g and 153.6g in tomato and grapes respectively using the solar dryer was achieved as against 156.8g and 125.3g in tomato and grape respectively using the sun drying method and indicating 43.1g and 28.3g difference respectively,for ten slices of tomatoes and grapes dried over a particular day. The rapid rate of drying in the dryer revealsits ability to dry food items reasonably rapidly to a safe moisture. Key Words: Solar Dryer, moisture, weight of material,