Development of an Oscillating Drum Granulator Prototype for Cassava Pearl

This paper presents an oscillating drum granulator prototype for cassava pearl. Effects of filling degree and oscillating speed on cassava pearl granulation were investigated. A stainless steel drum granulator with 50 cm diameter and 16 cm length was developed. The stainless steel joints with a cotton-transmitting belt were used to connect the drum to an oscillator arm to simulate the flexibility of a traditional cloth cradle granulator. The filling degree and oscillating speed were varied from 1, 2 and 3 kg and from 87 and 100 rpm, respectively. During granulation, samples were taken at 4, 8, 12 and 16 minutes to determine the particle size distribution, mass mean diameter, granule density, hardness and sphericity. The results indicated that both the filling degree and oscillating speed played an important role on cassava pearl granulation. The filling degree of 3 kg and oscillating speed of 100 rpm was suggested since it yielded similar properties of cassava pearls to those obtained from the traditional process. This prototype granulator could successfully produce 2.4-mm pearls with comparable characteristics to the standards. Comparing to a traditional granulator, the oscillating drum granulator is easier to clean and more GMP compliant.