DESIGN, CONSTRUCTION AND PERFORMANCE EVALUATION OF AN ALMOND KERENEL EXTRACTION MACHINE

A low-cost Almond (Prunus dulcis) kernel extraction machine was locally designed, manufactured and evaluated. Kernel extraction by the machine was conducted by first crushing the nut, and then separating seeds from a shell. The performance of the developed machine was evaluated in terms of machine productivity, cracking efficiency, kernel breakage and specific energy requirements. The evaluation was conducted at roller speeds (ranging from 0.5 to 1 m/s), rollers clearance (ranging from 14 to 25 mm) and two different roller casing materials (rubber and metal mesh). Results revealed that the increase of the roller speed was found to increase the machine productivity. However, it caused a decrease in the kernel breakage, cracking efficiency, energy requirements and the extraction cost. At all levels of roller speeds and both casing materials, the clearance between rollers of 16 mm resulted in lowest values of energy requirement, extraction cost and highest values of machine productivity. On the other hand, the clearance between rollers of 14 mm resulted in the maximum values of cracking efficiency. The use of rubber casing was found to increase the machine productivity, cracking efficiency and decrease the kernel breakage, energy requirements and extraction cost.