KNOWLEDGE

palm oil pressing process

We will introduce palm oil pressing process for you.

It is the woody oil plant with the highest yield per unit area in the world. The yield per mu of its main product, palm oil, can reach 200kg, which is 5-6 times that of peanuts and 10 times that of soybeans. I will palm oil pressing process.

In the traditional sense refers to the pressed palm fruit pulp, which is different from palm kernel oil obtained by pressing the nuts. Palm oil, soybean oil and rapeseed oil are also known as “the world’s three major vegetable oils”.

The palm fruit bundles picked by farmers in a cycle must be transported to the factory for processing on the same day. The quality of crude palm oil depends on the integrity of palm fruit bundles. Once the palm fruit is damaged, it will quickly deteriorate. Thus affecting the quality of crude palm oil.

How to press the palm kernel oil

To extract palm kernel oil from the palm fruits, a palm fruit crushing plant is necessary. The main products of this plant are crude palm oil and palm kernel, and the processing capacity is about 60~100 tons of palm fruit bunches per hour.

For crude palm oil, it generally needs to go through processes such as sterilization, threshing, cooking, pressing, washing, purification, and drying. These processes help to refine the oil and remove impurities, ensuring its quality and shelf life.

For palm kernels, after pressing and separating from the fruit bunches, they also need to go through processes such as kernel/fiber separation, kernel conditioning, kernel crushing, kernel separation, and palm kernel drying. These steps are crucial for extracting high-quality palm kernel oil.

Once the palm kernels are dried, they are sold to palm kernel mills where they are processed further to extract palm kernel oil. The extracted oil is then ready for sale and use in various applications.

1. Sterilization as the first step

in palm fruit pressing is crucial to the quality of the final product palm oil. The purpose of sterilization mainly has the following points:
 Inactivate the activity of lipase and prevent the rise of free fatty acids
Easier release of palm fruit from the bunch
Soften the peel, making it easier for the oil to separate out
Nucleolus modulation, reducing nucleolus fragmentation in subsequent processes

2. The main function of threshing is to separate the palm fruit from the fruit bunch.

The sterilized palm fruit bundles will be conveyed into the drum thresher, and the palm fruit will be separated from the stalk as the drum rotates. The stalk is a component that does not contain any oil. So the loss during threshing is mainly due to the palm fruit still attached to the stalk after threshing. If the sterilization time is too short or too long.

It will affect the loss of threshing. If the time is too short, it is difficult to remove the palm fruit. If the time is too long, the stem will absorb the separated palm oil. Usually the stalks are burned and the ash is used to make potash, biofuel or sent back to the plantation as fertilizer.

3. The palm fruit after cooking and pressing and threshing

It is transported into the cooking pot and reheated with direct or indirect steam. A central shaft with stirring fins is installed in the cooking pot, and the palm fruit is stirred accordingly, and the pulp becomes soft and peeled from the core at high temperature. The mixture is then sent to the pressing equipment. To help the grease flow, hot water is also added.

Surely,the mixture of crude oil and hot water is collected into the clarification tank to wait for clarification, palm kernel, fiber and other impurities are discharged from the filter cake and enter the palm kernel oil preparation process.

In addition,the pressing process needs to maximize the extraction of palm oil from the pulp without breaking the nuts. Because the palm kernel oil after the nuts are broken will pollute the crude palm oil and affect the quality. The use of two or more pressing processes can effectively reduce the broken rate of nuts.

4. Purification and clarification

The mixture in the clarification tank is crude palm oil, water and a small amount of solid particles. The traditional clarification method is to use gravity separation. The mixture will be heated to 85-90°C and allowed to settle for 1-3 hours.

The oil on the surface will be transported to a centrifuge to further remove impurities in the oil, and then transported to vacuum drying. The slag at the bottom of the clarification tank will also enter the centrifuge to recover the crude palm oil inside. Finally, it will be vacuum-dried and stored at a temperature of about 45°C.

5. Wastewater in palm crushing factories

In fact,the factory will generate about 0.65 tons of wastewater for every 1 ton of palm fruit bunches processed. These wastewaters will affect the environment because of their high acid value, high BOD value and high COD value.

Finally,Generally speaking, the anaerobic or aerobic reaction in the treatment tank can reduce the BOD to below 100mg/L. In areas with stricter environmental protection requirements, more advanced processes will be used to treat these sewage.