Performance Study of STR Dryer for Paddy

Abstract

The study was conducted with a view to evaluate technical performance of a STR dryer in Bangladesh and to assess adaptability of the dryer at small paddy traders and large farmers’ levels in Bangladesh. The experiment was conducted during December 05-07, 2014 at the workshop of the Department of Farm Power and Machinery, Bangladesh Agricultural University, Mymensingh, Bangladesh. The capacity of the STR dryer was about 300 kg per batch. The study was conducted with two kinds of samples. Firstly in experiment- 1 and 2, the dryer removed moisture content of paddy from about 18.2% to 12% on an average 3 hrs time. Secondly, in experiments 2, 3 and 4, it removed moisture 14.1 to 10.9% (wb) on an average 2 hrs of time. The ambient air temperature and relative humidity were about 18.36°C-28.95°C and 55.4%-91.8%, respectively. The drying temperature of STR dryer for paddy drying was in the range of 38°C to 42°C. The drying and the heat conveying efficiencies of the STR dryer were found about 31.2% and 19.91%, respectively. The overall dryer efficiency was found about 22.7%, which satisfy the standard batch dryer performance. Considering the level of technology and the capacity, STR dryer meets the requirements of small paddy traders and large farmers of Bangladesh and recommended for adaptation in Bangladesh conditions.