Design and Development of a Continuous Fluidized-Bed Gari Dryer

Fluidization technique is a viable, reliable and more efficient method of producing hygienic gari. In this work, a hot air continuous fluidized-bed dryer for cassava particle was designed, constructed and tested. A feeding subsystem which includes hopper and rotary feeder was also designed and fabricated to control the particle feed rate into the drying column. A rectangular drying column of dimension 0.4 m x 0.8m x 1.0 m was constructed. A perforated rectangular plate was used as a distributor grid. The bed was tilted at an angle of repose 15 °C to assist the discharge of the product through product outlet, This machine also comprises a centrifugal blower, a temperature controller and a 9 kW air heater. The dryer was tested using a drying temperature of 120 °C and 150 °C at a varied time interval of 5 mins and 2mins with variable blower operating conditions. The dryer took 22 mins lo attain a steady temperature of 150 °C with blower on and 8 mins when the blower is off. After feeding, it took 18 mins to dry and roast or fry 2kg of gari at 150 °C and 24 mins at 120 °C. In conclusion, this dryer is very efficient and productive when compared with the manual, local, convectional and modem existing techniques.

Keywords: Fluidization, Gari, Fluidized-Bed Dryer, Heater, Blower.