Design, Development and Performance Evaluation of a Small-Scale Solar Assisted Paddy Dryer for on Farm Processing

With the continued escalation in population growth and the expansion of international food trade and demand of high quality product for food security at low cost has created considerable interest in the development of new post-harvest technologies. This is particularly important for developing countries where post-harvest losses of cereals are between 10-20% and of fruits and vegetables as high as 20-100% A new solar assisted paddy dryer with central air distribution model (along the length of drying chamber) has been developed. Due to this distinct feature of the dryer high drying rate was achieved during the drying processes. Other components of the dryer are perforated drying chamber, blower and flat plat solar air collector. Dryer was evaluated using 100kg of freshly harvested paddy at 23.78% moisture content (wb). Performance evaluation results showed that the mean drying rate of the solar assisted paddy dryer was 0.87kg/hr per for every 100kg, whereas 0.46kg/hr was the sun drying rate comparatively. The faster drying rate of the dryer reveals its suability to dry the paddy for its safe storage moisture content rapidly. By using the solar assisted paddy dryer, approximately 50% saving in time was also achieved as compared with the traditional sun drying method. Solar assisted paddy dryer took 10hr for drying the 100kg paddy up to 14%, while sun drying method dried paddy up to 13.89% in 19 hours. Cost analysis also showed that, by using solar assisted paddy dryer we can dry good quality paddy at low cost as compared with the open sun drying method. For development of agriculture in the rural areas, commercial size of the solar assisted paddy dryer can be amplified and produced at community level.