Development of Grating and Dewatering Units of a Cassava Processing Machine

Abstract

The cassava processing machine that combines two units’ major operations of grating and dewatering was developed. The development of the machine prototype involved design, fabrication and performance evaluation. The machine which is simple to operate and maintain was powered by 2.2 kW (3.8 hP) single phase, electric motor. The machine was tested with five grater speeds (1100, 1200, 1300 1400 and 1500 rpm), dewatering with five speeds (150, 200, 250, 300, and 350 rpm) and five compression spring loads (100, 200, 300, 400 and 500 N). The recommended cassava variety TMS 30110 was also used. The results obtained from the performance of the machine showed a significant improvement over similar machines. The results from performance evaluation of the cassava processing machine showed that, 1400 rpm grater speed has the highest grating capacity and efficiency. Also in the combine machine (grating and dewatering) experiment, 1400 rpm grater speed, 300 rpm screw expeller speed and 400 N compression spring load has the highest machine capacity, throughput and efficiency of 114.23 kg/h, 95. 88 kg/h and 83.9% respectively from 10 kg cassava tuber. The moisture content 46% wb obtained was within the recommended value. The losses recorded during machine operation was minimal.