Oil extraction process of rapeseed

Rapeseed, also known as Brassica, is an herbaceous cruciferous crop, one of the main oil crops and nectar crops in China, and its grain is one of the main varieties of oil extraction raw materials. Cultivated all over China, it is divided into winter rape and spring rape. Its planting area accounts for more than 40% of China's total oil crop area, and its output accounts for more than 30% of China's total oil output, ranking first in the world.

Cleaning and drying of rapeseed

If the soil, stems and leaves and other debris contained in rapeseed are not removed before entering the oil press, it will not only affect the quality of oil and cake, but also absorb part of the oil and reduce the oil yield. If the rapeseed contains sand, metal, hemp rope and other sundries, it will cause wear and tear of the parts, induce production accidents and affect the process effect. Therefore, in order to ensure the smooth progress of production, impurities must be removed as far as possible, a few rapeseed fruits with high water content, in order to peel convenient, drying treatment is also very necessary.

Heat treatment

Heat treatment is one of the most important processes in the process of oil extraction, including the wetting and heating of raw billet, which is called steaming billet or fried billet in production, and the billet after steaming and frying is called cooked billet. Raw billets that are pressed after heat treatment are called hot pressing, and those without heat treatment are called cold pressing. Rapeseed is mainly hot-pressed. The effect of heat treatment has a direct impact on the smooth progress of the whole oil production process, the oil yield and the quality of oil products and cakes.

Press

The round press bar of the press has a zigzag curve and conical surface. When the rapeseed is pressed, the volume of the press screw and the inner wall space of the press cage is constantly changing due to the push and extrusion of the press snail. The inner wall of the press cage is serrated, where the billet is pressed and relaxed alternately, and the structure of the billet is constantly adjusted to get uniform turning. So that the unsqueezed oil or the billet with less oil is more likely to be fully squeezed.