The palm oil refining industry has witnessed a commendable growth in recent decades and thus, has emerged as one of the vital manufacturing sectors in the world. Further, it has gradually become the most abundant traded vegetable oil in the world, owing to the growing demand. Malaysia is the largest exporter and producer of crude palm oil in the world.

The crude palm oil is gathered from the mesocarp of the palm oil. However, the crude palm oil that has been extracted contains unwanted impurities and requires a refining process to partially or eliminate them to produce edible oil.

In the current scenario, palm oil is widely used in tropical countries in South East Asia, Africa, and parts of Brazil for cooking purposes. Further, due to its low costs and oxidative stability, palm oil has grown popular in these regions.

As mentioned before, crude palm oil that is extracted contains impurities that require a refining process to improve the quality, physical appearance, oxidative stability, and other properties. The impurities are removed at a refinery plant, and thus, it is essential to ensure that the plant is modern and equipped with advanced technologies to make the process efficient.

Before you implement the Agitated thin film dryer in your industrial plant, check for the various aspects of this evaporator:

• Phospholipids
• Free fatty acid
• Coloring pigments
• Oxidative materials, moisture, water-soluble impurities, metal impurities

The term refining suggests the removal of the impurities mentioned above to enhance the shelf life and quality of refined vegetable oil.

The refining process of palm oil includes the following:

• Bleaching
• Deodorisation
• Fractionation

The crude oil is refined using two methods, including physical refining and chemical refining, during which FFA is removed to ensure that the FFA content is not more than 0.1 %. It is essential to note that physical refining is environment-friendly in comparison with chemical refining. Further, it is also vital to understand that regardless of the method of refining used, advanced equipment and machinery are used to extract oil from the palm seed.

Let’s understand the different aspects of the refining process and get an in-depth understanding of the same.

Bleaching

Bleaching edible oil and fat is one of the most crucial aspects of refining crude oil and fats. It is carried out to ensure that the contamination that affects the physical appearance and quality of the oil is removed efficiently. Moreover, before commencing the bleaching process, gum treatment is carried out using phosphoric acid. Here, the gums are separated in the pressure leaf filter once bleaching is complete.

During the bleaching stage, impurities such as trace metal complexes including copper & iron, phosphatides, and oxidative products are removed. Further, the bleached oil is then filtered in industrial filters such as filter press or hermetically sealed vertical leaf pressure filter. Bleaching guarantees enhanced quality and purity.

Deodorization

As mentioned before, edible refining oil is segregated into two parts – physical refining and chemical refining. Although deodorization is required for both types of refining, the working principle of the deodorizer is different for both processes.

In physical refining, the FFA is removed at the Deo section. Further, as palm oil is a hard oil, physical refining is necessary as it has high FFA content. Deodorization is performed to eliminate volatile components including, aldehydes and ketones that are responsible for the smell of refined oil. In the process of deodorization, the free fatty acids are effectively removed as palm fatty acid distillate as a refining waste.

Apart from removing free fatty acids, other impurities including carotenoids pigments, and primary and secondary oxidation components that are present in palm oil are also removed. In a nutshell, the deodorization process is nothing but a steam distillation process that is performed at low pressure and high temperatures (180-220 ° C).

In chemical refining, the deodorizer is responsible for removing odor, and bleaching to eliminate the color that is remaining and to recover the fatty acid distillate.

Fractionation

Once the deodorization process is complete, the oil is cool by using cold fractioned oil to ensure maximum heat generation. Further, the oil is then cooled in cooling tower water up to 40-45 ° C and then cooled by the outgoing oil that is chilled fractioned. Moving on, the oil is then chilled to fractionation temperature in the crystallizers.

The oil is then kept in the crystallizers at the right temperature of the oil which eventually results in the formation of wax and adequate growth of the crystals. Next, the step cooling is carried out to ensure complete maturation of the crystal enhances the efficiency of the plant. The chilled water is used to cool the oil to the right fractionation temperature.

There are two primary chillers available in the market at present including, a power chiller and a vapor absorption machine. Once the desired temperature is achieved, the crystallizer mixture is then sent to the filter press to separate Stearin from palm olein.

CentPro is an established manufacturing company that offers a diverse range of process and chemical equipment for a plethora of industries. Our experience and expertise in providing the most effective, optimum, and reliable solutions related to edible oil refinery plants are unmatched. An edible oil refinery plant requires high-quality, well-designed, and defect-free machinery. Besides, apart from offering advanced machinery, we ensure that a minimum quantity of contaminants and odor-producing agents are utilized.