PERFORMANCE EVALUATION OF AN AUTOMATED CASSAVA PEELING MACHINE

Abstract

The performance evaluation of an automated cassava peeling machine was carried out using 3 different level of moisture content of the cassava tuber; Mc1 = 69%, Mc2 = 62%, and Mc3 = 57% .Mc 2 and Mc 3 were obtained by leaving the tuber for a day and two after harvest respectively. Four ranges of machine peeling tool speed of1100rpm, 1400 rpm, 1700rpm and 2000rpm obtained via belt and pulley conversion from a 5 Hp petrol engine with maximum speed of 3000 rpm were used. The experiment also put into consideration the tuber characteristics namely tuber length, tuber diameter and tuber weight which caused the grouping of cassava tubers based on their averages length and diameter into four groups namely A (37cm; 9.68cm), B ( 21.97cm; 7cm), C(18.6 cm; 5.43 cm), and D ( 10.8cm; 4.22cm) which were fed into the machine at three different feeds of 2kg, 4kg and 6kg in order to check for the effect of feed on the machine performance. Generally, the combine effects of machine speed, tuber characteristics and feed on themachine performance evaluation parameters at varying moisture content were checked. Result reveal an increasing peeling efficiency as the tuber characteristics and machine speed increasefrom 1100 rpm to 1400rpm and 1700 rpm but decrease afterwards at 2000 rpm with the highest individual test efficiency being 93.89% for category A at 1700rpm and 4kg feedwhile the least was 49.8% for category D at 1100rpm and 2kg feed thus making 1700rpm the optimum peeling speed at 69% and 62% moisture content but 1400 rpm speed for 57% moisture content.The combine effect of machine speed and tuber characteristics on tuberloss shows a decrease in tuber loss as the tuber characteristics increases while the moisture content hadsignificant effect on the tuber loss and peel retention as well asthe peeling efficiency. Also feed of 4 kg gave the highest average efficiency of 83.74 %, against 2kg and 6 kg feeds although feeding the machine with 6kg of tubers offered better performance than feeding with 2kg. This implies that less of the tuber is damaged as the diameter, length and weight of the cassava fed into the machine increases. Similarly, the peel retention increases as the tuber characteristics reduces but reduces as the speed increases. The multiple linear regression models between the performance evaluation parameters and the independent variable of tuber length, tuber diameter, tuber weight, moisture content, feed and machine speed yielded very good output. The overall model parameters are significant at P < 0.05 for all the performance evaluation parameter used. The results show an R2 and standard error of0.69454 and 1.09%; 0.819 and 5.4%; 0.823 and5.29% for Tuber Loss, peel retention, and peeling efficiency respectively.