Performance Evaluation of a Melon Shelling Machine with Different Power Sources

Abstract

Performance evaluation of an electric motor and a fuel-engine powered machine used for shelling melon seeds was performed in this study to determine the effects of shelling speed and moisture content on machine productivity. The melon seeds used for the evaluation of the existing melon shelling machine were sourced locally from Umungasi market in Aba, Abia state, Nigeria. The unshelled melon seeds as used were weighed (25g each), sprinkled with water and partially dried with natural air for 25 minutes. This enabled the skin coat became slightly softened and the cotyledon easily detached from the shell, thus making the shelling more efficient. To evaluate the parameters (machine productivity, throughput capacity and percentage seed damage), the melon seeds were employed. For the shelling performance, melon seeds of five different moisture contents (7.48, 10.24, 13.92, 18.36, 21.44%) dry basis (d.b.) at different shelling speeds (850, 1000 and 1200 rpm) were utilized in the evaluation. From the evaluation, results revealed that the machine has an optimal productivity of over 83% and percentage seed damage of 14.2% at seed moisture content of 21.44% and drum speed of 1200 rpm for both power sources. Maximum machine throughput capacity of over 940 kg/h was recorded at 1200 rpm and 21.44% moisture content for both power sources. Overall, results obtained indicated that the machine can effectively shell melon seeds and that seed moisture contents and shelling speed affected the machine productivity.