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Edible oil generally contains wax. The wax content of different edible oils is very different. Most edible oils have very little wax content and can be ignored. However, some edible oils have higher wax content, such as sunflower oil, rice bran oil, safflower oil and corn oil. These waxes cannot be absorbed by the human body and cannot be saponified, so these edible oils need to be dewaxed. The edible oil dewaxing equipment produced by Henan Zhongxing is used to remove a small amount of wax or saturated fat in the oil to ensure the stability and transparency of the edible oil in cold storage. The edible oil after dewaxing has a high value and can meet the national first or second oil standard.

Edible oil dewaxing is also called winterization, which is a process of separating wax under low temperature conditions. The general process of edible oil dewaxing: After the edible oil is slowly cooled to 5-10°C, keep it warm for at least 6 hours to crystallize the wax. After the crystallization is stable, the oil temperature is usually raised to about 15°C to reduce the viscosity and facilitate filtration. Sometimes to promote crystallization and filtration, filter aids are usually added to the crystallizer. The amount depends on the wax content, generally about 0.2% to 1%.

Edible oil dewaxing process:

Oil to be dewaxed → heating → heat exchange → cooling → crystallization → crystal growth → filtration → heat exchange → refined oil

1. Heating:

Before edible oil is dewaxed, the oil temperature is basically within 30°C, while the melting point of wax is 79-81°C, so some wax has been precipitated in the oil. If crystallization and crystallization are carried out directly, it will affect the precipitation and crystallization effect of wax. Therefore, it is necessary to heat the oil that has precipitated wax at the beginning to make all the wax dissolve in the oil.

2. Heat exchange:

The heated oil is exchanged with the dewaxed oil by a plate heat exchanger, and then cooled with chilled brine and transported into the crystallization tank. 

3. Cooling:

The cooled oil is further cooled in the crystallization tank. Appropriate stirring is needed to make the precipitated wax molecules collide and at the same time make the waxy oil cool evenly. The speed should not be too fast, otherwise the particles that have crystallized will be broken, which is not conducive to crystallization.

4. Crystal growth:

After the waxy edible oil is continuously cooled and crystallized to the specified temperature, the stirring is stopped and kept for a long time to make the uncrystallized wax continue to crystallize out, so that the small crystal grains continue to grow, and the crystal is grown.

5. Filter:

The crystallized waxy oil is filtered by self-flow or pumped into a hot-discharge winterization filter. In the process of crystallization and crystallization of edible oil, most of the wax and solid fat are precipitated (approximately 1-2% of the oil volume). Two large-area thermal unloading winterization filters are selected, one for filtering and the other for wax unloading, so that production can be maintained continuity and production efficiency can be improved.

6. Heat exchange:

The filtered oil is pumped into the plate heat exchanger for heat exchange with the undewaxed oil, and then stored in storage to obtain product oil. 

The refined oil after dewaxing is more conducive to storage, the quality will be improved, and the value will be higher. Many edible oil manufacturers will choose edible oil dewaxing equipment to refine edible oil. If you also have needs in this regard, you can contact Henan Zhongxing. Our engineers will set specific dewaxing parameters according to your edible oil quality, and are equipped with factory direct edible oil dewaxing equipment. I believe you will have a good harvest.