Properties influencing cracking and separation of palm nuts in a mechanical cracker cum separator

Abstract

Experimental studies of some properties influencing cracking and separation of palm kernel from the shell was conducted in a palm kernel dual processing machine. A mechanical cracking cum separating machine was developed for the study. The cracking unit consists of feed hopper, impeller shaft, cracking drum and impeller blade. The nut falls by gravity through the hopper channel into the cracking drum where the cracking process takes place through the help of impeller blades that flip the palm nut against the walls of cylindrical cracking drum. The mass of cracked nut flows through the separating unit that separates the kernel from the shell. The separation is induced by high current of air mass generated by an axial fan. A dura palm variety was selected and a total sample of eighteen thousand (18000) palm nuts were obtained and divided into two groups (feed rates), A and B, of eight thousand and ten thousand palm nuts respectively. Sample groups A and B were further divided into five sub -groups of four hundred (400) and five hundred (500) palm kernel nuts. Each sub group (feed rate) was replicated four times at different shaft speeds (600, 900, 1200, 1500 and 1800 rpm). Results showed that cracking efficiencies increased with respect to speed. Un-cracked nuts percentage ranged from 1.3 to 5.3% at 7.1% moisture content, and 1.6 to 4.5% for 400 and 500 feed rates, respectively. Cracking time for both feed rates decreased with shaft speed. Throughput capacity of 11.49 kg/h was observed to be the lowest at 600 rpm and moisture content of 7.1% for both 400 feed rates and the highest throughput capacity of 37.16 kg/h was recorded at 1800 rpm at moisture contents of 9.3% and 16.1%. The results of this study shows that moisture content, engine speed and feed rate are significant parameters that influence cracking of nuts and separation of palm kernel from the shell.

The Comparative Analysis of a Developed Swing Beater and Conventional Beater of a Palm Nut Cracking Machine

“…to highest value of 97% at 8.92% moisture content (db.). The decrease might be due to the fact that the palm nut become more brittle and susceptible to cracking at low moisture content (Olaoye and Adekanye,., 2018). Kilanko et al (2018) reported that the shell of the nut is naturally spongy and tough at lower moisture content.…”

Development and testing of a vertical-spikes shelling machine for bambara groundnuts

“…The allowed bending stress (γ d ), and safety factor (SF) for the shaft with keyways were 40 Nm.m -2 and 1.5 respectively (Hassan et al, 2009). The shaft diameter was calculated to be 24 mm from Equation 16 (Olaoye and Adekanye, 2018). The standard available shaft size of 25 mm diameter was selected for this study based on the power calculations above.…”

“…The machine performance was evaluated by measuring the weight of groundnuts shelled per unit time. Equation 29 was used to calculate the machine capacity (Olaoye and Adekanye, 2018).…”

Improving the Quality of Locally Produced Vegetable Oils in Ghana Using Zeolite ZSM-11

“…% MC= (W2-W3 (moisture loss))/(W2-W1(fresh weight)) ×100 The same procedure was used by [25] in their recent research work on the properties affecting the cracking of palm nut.…”