Drying of Paddy Seed Using Flat Bed Drier

Abstract

This study was conducted to evaluate the field level performance of a flat bed drier. The flat bed drier installed at Agriculture farm, Bangladesh Agricultural University, Mymensingh, was used to investigate the performance of the dryer for drying of paddy seed. The drier consists of an axial fan, a biomass furnace and a drying bin with perforated floor. Two sets of full scale experimental runs on drying of paddy seed were carried out in the month of May, 2007 and 2008. During drying ambient temperature, relative humidity, inlet air temperature and air flow rate were measured at fifteen minutes interval and three samples were collected to measure the moisture content at one hour interval. The performance of the dryer was evaluated in terms of the drying rate, specific energy utilization, drying efficiency and operational cost, pay back period and quality of dried paddy seed. The paddy seed was dried from 23.3 to 15% moisture content (wb) within 8 hours using inlet air temperature in the range of 3742°C and air flow rate in range of 0.18 0.23 m/s. The specific energy utilization, drying efficiency and operational cost were 454 kJ/kg, 74% and Tk. 0.41/kg respectively. Pay back period of the drier is about three months for drying seed paddy and about 14 months for drying paddy for consumption. The germination percentage and viability of dried paddy seed were 71% and 96.6% respectively. The drier was found suitable for drying of paddy seed in Bang Bangladesh especially during rainy season.