Development of a small screw expeller for extracting oil from linseed [electronic resource].

Includes references.

The main objective of the present study was to develop a small and simple expression machine for oil extraction from most common oilseeds by cold pressing. The machine was designed and constructed at the machine shop of Agricultural engineering research institute, (A En R I). The effect of major parameters were investigated such as: screw type, screw revolving speeds, outlet clearances and moisture content of oilseeds and their effects on machine feeding rate, expression efficiency and energy requirements. Two versions of the screw expeller were tested: the standard and the tapered screws. The oil expression efficiency decreased as both the screw speed and outlet clearance increased. The expression efficiency increased with the increase of the oilseed moisture content from 6.3 to 9 %. But increasing of oilseed moisture content from 9.0 to 12.0 % tended to decrease the expression efficiency. However, the tapered screw recorded the highest values for the maximum and minimum efficiencies than the standard screw. Increasing the screvy speed and oilseed moisture content, with the decrease of outlet clearance tended to increase the energy requirement. The tapered screw needed more energy than the standard screw. Generally, the optimum operating conditions of the tapered screw gave reasonable expression efficiencies 84.26% and 63.44% at of the tapered screw that screw speed ranging from 30 to 50 rpm, 0.4 mID outlet clearance and 9.0 % oilseed moisture content. The total costs of the machine were estimated at 3.73 and 3.79 L.E/h for standard and tapered screw respectively at the optimum conditions.

Summary in Arabic.

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