A STUDY ON THE PERFORMANCE OF A POLYVINYL CHLORIDE (PVC) PASSIVE SOLAR DRYER FOR PERISHABLE CROPS
This research aimed to design, develop, and evaluate a passive solar dryer for perishable crops. The dryer consisted of a drying tray, cover sheet, absorber plate, insulator, and drying chamber. It was designed to operate as a batch dryer, with heat energy for drying supplied by concentrating solar radiation on the collector. Heat transfer to the drying materials and mass transfer from the drying materials were achieved through a natural convective process (passive operation mode). The study demonstrated that both okra and pepper could be effectively dried using solar dryers and traditional sun drying methods, with okra generally drying faster than pepper. The solar dryer removed 0.243 kg of water from okra and 0.133 kg from pepper, achieving efficiencies of 15.63% and 35.52%, respectively. In contrast, the sun drying method removed 0.225 kg of water from okra and 0.137 kg from pepper, with efficiencies of 34.21% and 33.50%, respectively. The solar dryer was evaluated using only pepper and okra, which might limit the generalization of the findings to other fresh horticultural materials. The developed solar dryer can be improved by optimizing its design variables (drying chamber size, collector area size, and material) and process variables (maturity level and size of horticultural materials to be dried), as these factors can significantly influence the efficiency and effectiveness of the passive solar dryer.
Authors : Tashiwa, Y.I., Bwade, E.K., Tumba, J.U. and Kabri, H.U.
Category : Open Access Volume (Issue) : 11(2) Date Uploaded : 23rd July 2025