Before oil extraction, certain processing of oil plants should be made. Different processing methods will directly affect the normal work of oil press and the oil yield. Different oil plants have different processing methods. The following are the main methods:
1. Impurity removing: most of the oil plants contain some impurities (such as sand, stone, iron, etc.). With careful screening, it will directly accelerate the wear of parts in oil press, reduce the rate of oil, and even lead to machine breakdowns and accidents. The supporting equipment include vibrating screen, stoning machine and magnetic separator.
2. Shelling: some oil plants like peanuts need to be shelled before pressing. Most people would shell the peanuts before pressing to increase the oil processing capacity and oil yield and improve the purity of the oil. The supporting equipment include peanut sheller, separating sieve and separator.
3. Crushing: though some oil plants can be extracted as a whole, oil yield can be improved by extraction of the uniform small particles after crushing and flaking of these oil plants. While some oil plants have large hardness (like camellia seed and grape seed), they must be crushed before pressing. The supporting equipment are the crusher and flaking machine.
4. Cooking: It is an important way to improve the oil yield. Oil temperature and humidity have direct impact on the oil yield. Usually the oil plants should be moisturized first, and then use the frying pot to fry the seeds to achieve the optimum oil temperature and humidity.