Performance Enhancement of Inclined Bubbling Fluidized Bed Paddy Dryer by Design Modification

Phyu Phyu Thant, P. Mahanta, P.S. Robi

Present paper discusses the bed inclination and passive inserts of dryer on drying of paddy in a bubbling fluidized bed dryer. Paddy was dried in three different inclined positions, viz., vertical bed (0° inclined), 15° and 30° in a bubbling fluidized bed. Experiments were conducted for 0.5 to 2.5 kg batch size with superficial velocities of 1.1 m/s and 1.6 m/s. All the experiments were repeated with and without spirals inserts. Results were obtained for air temperature of 55°C, 60°C and 65°C and air velocities of 1.1 ms^-1 and 1.6 ms^-1 respectively. Better results in terms of energy consumption and moisture removal rate were observed with bed inclination of 15˚. Use of spirals inside the drying chamber with inclined dryer reduces drying time as well as reduces energy consumption significantly.