Research and application of twin-screw press for cold pressing of de-hulled rapeseed

In order to solve the technical problems of cold pressing of de-hulled double-low rapeseed, a new twin-screw press with a principle of combination of joggling and non-joggling was designed and manufactured, the pressing chamber of which had characteristics of multiple-stage compression and relaxation and a thin layer of materials when pressing. Theoretical compressing ratio of the twin-screw press is 23.0, and ratio of length and diameter of pressing chamber is 11.5, and pressing time is 180 seconds. In the twin-screw press materials could be cleaned up intensely so that the problem of de-hulled rapeseed feeding was solved. The twin-screw press was applied to cold pressing of de-hulled rapeseed successfully. The oil content of cold pressing cake is reduced to about 15%. Cold pressing oil approaches the Standard of National Ⅲ Rapeseed pressing Oil. Cold pressing cake temperature is lower than 70℃ which assures good quality of cold pressing oil and cake. Twin-screw press is fit for the cold pressing of de-hulled rapeseed with obvious improvement of quality of rapeseed oil and reduction of energy consumption, which can increase processing value of double-low rapeseed.