Comparison of the Mechanical Behaviour of Selected Oilseeds under Compression Loading

Abstract

The present study provides information about the comparison of mechanical behaviour of selected oil bearing crops namely rapeseeds (Brassica napus L.), sunflower seeds (Helianthus annus L.) and jatropha seeds (Jatropha curcas L.) under compression loading. In this research, the compression device ZDM 50 with a chart recorder and a pressing vessel with diameter 100 mm were used to determine the relationship between the magnitude of the pressing force and deformation characteristics of the oilseed crops pressed at initial height 80 mm. From the compression test, the amounts of true deformation, maximal deformation energy and compressive force of the pressed samples were calculated and also mathematical equations describing the limit deformation, maximal deformation ratio, energy ratio and oil point deformation ratio were determined. The oil point position on the deformation curve, that is, the first leakage of oil from the pressing vessel of the various oilseeds was determined and compared. Based on the measured amounts rapeseeds achieved the highest values followed by jatropha seed and then sunflower seed. The amount of deformation energy required for the seed deformation gives the indication the amount of energy needed for obtaining the oil from the seed. It was found that the measured amounts as well as the oil point position on the force-deformation curve of the pressed samples showed varying results due to the seeds physical and inherent characteristics.