Why should the impurities in the oil be cleaned in advance before oil pressing?

During the process of oil harvesting, drying, transportation and storage, some impurities such as gravel, soil, stems and leaves, iron ware, etc. will be mixed. If it is not removed before production, it will be very detrimental to the production process of the oil press.

What impurities are contained in the oil?
What impurities are generally contained in the feed oil? After oil is collected, sunned, transported and stored in the oil plant, it usually contains the following three types of impurities:
(1) Inorganic impurities: mainly refer to soil, sand, stone, tile, metal, etc.
(2) Organic impurities: including stems and leaves, husks, wormwood, hemp rope, cloth pieces, paper scraps, etc.
(3) Oily impurities: including diseases and pests, fake seeds and seeds mixed with other oils.

Why do we need to clean the oil before squeezing?
After removing impurities, it will bring the following six benefits to the oil production:
(1) Reduce the total oil loss and speed up the oil yield;
(2) Accelerate the quality of oil and pastry;
(3) Increase the processing capacity of the equipment;
(4) Reduce the wear of equipment parts;
(5) Avoid production accidents and speed up the process effect;
(6) Reduce dust flying, ensure the health of workers and change the production environment.

What are the methods of oil cleaning?
(1) Screening method - the main cleaning method. According to the different size and shape of oil and impurities, the oil is screened through different sizes and shapes of sieve holes.
(2) Air separation method - according to the different aerodynamic properties of oilseeds and impurities, use air flow to separate and remove floating dust and other impurities lighter or heavier than oilseeds through air separation equipment.
(3) Impact method - according to the difference in mechanical strength of oilseeds and impurities, the oilseeds and impurities are ground and impacted in the equipment to break the impurities, and then removed by screening method.
(4) Specific gravity method - according to the principle of different specific gravity of oil and impurities, specific gravity stone remover and water washing equipment (also called water separation method) are used to remove impurities.
(5) Magnetic separation method - according to the different principles of oilseed and metal magnetism, remove the metal (iron) in the oil with the help of magnetic separation equipment. In actual production, in order to effectively remove various impurities, it is not simply to use a certain method to remove impurities, but often to use a combination of multiple methods.