Oil seeds pretreatment & pressing machines


Type: Oil seeds pretreatment & pressing machines

Processing material: peanut, soybean, sunflower seeds, cottonseed, sesame, palm fruit

Capacity: 2-300T/D

Oil seeds pretreatment & pressing machines: Crusher, Dryer Expeller

Application: high efficiency, high oil extraction rate

Oilseed pretreatment & pressing machines are necessary for big capacity cooking oil processing factory, which influences the processing working behind and the quality of crude cooking oil.

Oilseed pretreatment & pressing machines include cleaning sieve, stones removal machine, magnetic selection machine, crushing machine, softening machine, flaking machine, drying machine and so on. Because different oilseeds have different pretreatment process, it should be designed by engineers according to customers’ needs.

The following are each section in oilseed pretreatment & pressing plant:

Oilseed pretreatment & pressing machines can remove impurity, regulate moisture and temperature, break oilseeds into small particles to change oilseed molecular structure, etc. And it is important for the following oilseeds solvent extraction process, which influences final edible oil quality.

1.Cleaning section:

Cleaning is the beginning of oilseed pretreatment & pressing machines, which can influence the final oil quality and machine life time directly. This section usually includes cleaing vibrating sieve,   gravity stoner, magnetic selection,etc. All oilseeds need this step to clean raw material and remove impurities.


2. Husking/dehulling/shelling section:

Husking/dehulling/shelling machine is to seperate shells from nuts. Some oilseeds like peanut/groundnut, sunflower seed, cotton seed, palm kernel have hard shells above nuts, they need shelling first. If pressing with shell, the residue oil rate is high, and final oil quality is not good. This section is for oilseed with shell.

Different raw material need different shelling machine, the following is peanut/groundnut shelling machine.

3. Drying:

Drying is to reduce oilseed moisture to proper moisture. Oil seeds might be harvested in rainy season with a high moisture, so drying is essential for storage and further processing. But some oilseeds don’t have to use drying machine, such as rice bran, corn germ, sesame and so on.

4. Crushing:

Crushing refers to with the mechanical size reduction process, oilseeds are crushed into small pieces. For big-size or hard oilseeds, crushing reduces its size to benefit flaking, while for prepressed cake, crushing turns cake to proper size and creats better oil yeild for second press or solvent extraction. Crushing is always necessary for soybean, peanut, palm kernel, etc.

5. Softening:

Softening adjusts moisture and temperature of oil seeds, softens and increases plasticity of oil seeds. For low oil content oil seeds (soybean, rapeseed/canola, cotton seeds, etc), softenning is an essential process for better flaking effect.

For example, oil content of soybean is 18-22%, while soybean is hard, low-moisture and low-temperature, flaking will bring plenty of powders without softenning. However, this needs to be stressed that whether softenning is needed still depends on the properties of oil seeds.

6. Flaking:

Flaking machine presses oil seeds from granulous to laminar, which brokes cell tissue of oil seeds and creats beneficial condition for cooking. Flaking also makes oil flows out smoothly when pressing or solvent extraction. Flaking roll is common for soybean.

8. Cooking:

Cooking is to wet, heat, steam and to cook flakes to change the internal structure of flakes, including destorying cells, protein solidification and denaturation, etc. All these changes makes oil easy to isolate and also enhance crude oil quality. Cooking pot can be used for processing groundnut/peanut, canola seed, cottonseed, sunflower seed, etc.

9. Pressing/prepressing:

Pressing/prepressing is to press oil from oil seeds or cakes. In general, there are several oil press machine for this step. Pressing section is mainly for processing high oil content, as groundnut/peanut,sunflower seed, canola seed, cottonseed, corn germ etc.