Evaluation of Drying Chili by Two Methods: Solar Assisted Heat Pump Dryer and Open Sun Drying

摘要

A heat pump dryer with assistant multifunctional solar thermal collector was used to dry chilies under the humid and hot weather conditions of Malaysia. The dryer was consisting of three main systems such as heat pump system, solar system, drying chamber. 15 kg fresh Chili with moisture content 80% (wb) were placed in heat pump-solar dryer to determine its possibility for drying chili. In the heat pump-solar dryer, drying of chilies was carried out at mass flow rate 0.15 kg/s with an average temperature of 46 °C and humidity chamber of 27%. Meanwhile, average temperature and humidity ambient was 31 °C, and 61% respectively for open sun draying chili. Moisture content of chili was reduced from 4 kg kg~(-1) to 0.05 kg kg~(-1) (db) in 32 h(4 days) in heat pump-solar dryer, while the moisture content of similar samples reduced to 0.08 kg kg~(-1) (db) from 4 kg kg~(-1) (db) by open sun drying method within 64h (8 days).