The main plant oils in China are two kinds of herbaceous oil and woody oil. Herb oil: soybean, peanut, cottonseed, rapeseed, sesame, sunflower seeds and other woody oil; then: camellia seed, walnut, coconut, olive, Buzura etc.. Pretreatments including oil cleaning, cashmere, peeling, drying, crushing, softening, flaking and cooking processes.

1. oil clean-up

(1) oil in harvesting, drying, transport and storage process will mix in some sand, soil, leaf and iron and other impurities, if not removed before production, is very unfavorable for the production process, impurities in the oil can be divided into organic and organic impurities and oil impurities in three categories. Inorganic impurities: dirt, sand, dust and metal; organic impurities: leaf, rope, hull and other seed oil; impurities: immature grains, heterogeneous oil, sieve the following provisions damaged oil and pest particles.

(2) the so-called "oil clean-up", that is, to remove impurities contained in the fuel process collectively. To clean up the technical requirements, not only to limit the amount of impurities in the oil, but also to clean up the proceeds after the waste oil content. After cleaning, the content of oil containing impurity (%): cold pressed soybean less than 0.05, hot pressed soybean 0.1, sunflower kernel (shell) 10, sesame less 0.1, peanut kernel 0.1, rapeseed 0.5, rice bran 0.05;

Clean up the leftover scraps of soybean oil containing limited: foot oil content is less than 0.5%, check the specification: 4.72 mesh sieve mesh / cm, wire diameter 0.55 mm. Round hole sieve 1.70 mm in diameter. Sunflower shell (including kernel) in oil content less than 1, check the screen size: wire diameter of 0.55 mm, 1.70 mm diameter round hole sieve; sesame oil content is less than 1.5 feet, 11.81 mesh sieve check specifications: mesh / cm, wire diameter of 0.28 mm, 0.70 mm diameter round hole sieve; foot in cottonseed oil the content is less than 0.5, check the specification: 5.51 mesh sieve mesh / cm, wire diameter of 0.50 mm, 1.40 mm diameter round hole sieve; rapeseed oil content is less than 1.5 feet, 11.81 mesh sieve check specifications: mesh / cm, wire diameter of 0.28 mm, 0.70 mm diameter round hole sieve.

Screening is the use of the difference between the grain size (width, thickness, length) of oil and impurities, and the separation of impurities by means of sieve holes. Commonly used screening equipment has fixed screen, vibrating screen and rotary screen. Their main work is the screen surface, according to the shape and size of oil and impurity particles, reasonable choice of sieve holes.

The air is used between the oil and impurities of the suspension velocity difference with the wind, a method for removing impurity. The main purpose is to remove the winnowing light impurities and dust, while also removing the impurities and heavy stones and clods, this method commonly used in cleaning cottonseed and sunflower oil. The wind separator can be divided into two types: blowing and suction.

Magnetic separation is the removal of magnetic metal impurities in oil by magnetic force. Oil commonly used magnetic separation device has two types: permanent magnet drum permanent magnetic drum.

The water is the use of water and oil contact directly attached to the surface of the oil to wash away the plaster, and according to the settlement of the proportion of different raw materials in water velocity ranging principle, at the same time, gravel, sand, and other heavy metal impurities in oil removal, and side by side mud may be in the infiltration of water under the loose into the fine water washed by water washing, can effectively prevent dust.

The shape, size and Oilseeds in equal or close, and the proportion of soil aggregate and oil is not very significant, known as the "side mud", especially in rapeseed and soybean, mud content is high in side by side, screening and winnowing equipment can not be effectively removed, must use a special method and equipment can be the main equipment of cleaning the mud alongside iron roller rice milling machine, rubber roller hulling machine, disc sheller, horizontal cylinder threshing and vertical cylindrical screen etc..

The cotton processing plant delinted cottonseed, during handling and transport will be in a certain amount of impurities, these impurities including inorganic impurities and organic impurities, in order to improve the yield of oil and oil cake, improve quality, increase equipment capacity, reduce equipment wear, improve working environment, to avoid accidents. It must be possible to remove the impurities.

2. cottonseed shedding

Cotton linter is also called the "cotton", is from the short fiber cotton linters cotton after take off the surface, it is an important raw material for extraction of cotton cellulose, also can be used in the manufacture of smokeless powder, celluloid and man-made fibers. Therefore, in order to obtain better oil production effect and increase economic income, cottonseed removal is an important production process in the process of making cottonseed oil from vegetable oil plants.

3. oilseed hulling hull and kernel separation:

(1) shelling equipment of sunflower seed sheller, disc sheller, knife plate peeling machine, roller sheller, shell kernel separation combination machine, separator, tallow seed shell cutter cage peeling machine, centrifugal sheller, roller sheller, shell kernel separation sieve.

(2) shelling requirements;

Kernel shell rate (3.94 mesh / cm sieve test), Cottonseed Kernel not more than 10%; peanut kernels not more than 1%; sunflower seed kernels no more than 10%.

The rate of kernel containing shell (HPS) cottonseed shells of not more than 0.5%; the peanut shell does not exceed 0.5%; sunflower seed shells of not more than 1% (such as a whole seed, and included).

4. oil drying

Oil drying refers to the dehydration of high moisture oil to suitable moisture content. Oil crops are harvested at times during the rainy season