Degumming Process

The following is some onsite photos of our edible oil refining projects including refining of palm oil. Feel free to contact us if you are interested!

Technically, degumming of palm oil is referred as an operation of purification in palm oil refining process, since crude palm oil (CPO) normally contains impurities in the colloidal state or dissolved in them. In degumming process, phospholipids featured of strong emulsifying action are removed by a variety of treatments. The objective is achieved by treating the CPO with specified quantity of food grade acid, normally phosphoric or citric acid of certain concentration, either singly or in combination. The precipitated materials are then removed by centrifuging, filtering or adsorption. In short, degumming of palm oil is a process of removing unwanted gums, so that to ensure the stability of the palm oil in later stage of refining plant.

Palm Oil Degumming Process (Dry Degumming)

Dry degumming is widely applied in refining low phosphatide oil such as palm oil, or used for preparing oils for further physical refining. Gums are removed through precipitation by acid conditioning and via filtration in the bleaching process, rather than centrifugal separation. It is a well-proven degumming method featured of cost effective. Below shows the flow diagram of dry degumming process of palm oil refining.

Dry degumming process of palm oil: For crude palm oil refining plant, drying degumming process is suggested. Classically, crude palm oil is first mixed with about 0.05– 0.1% concentrated phosphoric acid. Then, after a short retention time, about 1 or 2% acid-activated bleaching earth is added under vacuum at a temperature of 80–120℃. After a suitable contact time, the spent earth is removed by filtration. Phosphoric acid is mainly used by palm oil refiners especially in Malaysia, due to economical reasons. However, citric acid is also used in some cases. The critical factor affecting the quality of refined palm oil is the introduced amount of acid. Either over or under dosage can lead to darkening and offflavor problems of the RBD palm oil.

Except dry degumming, there are also other types of degumming methods applied in vegetable oil refining plant, such as water degumming and acid degumming. The main differences between these types lie in processing method and chemicals used. Besides, the selection degumming method is based on the content of phosphatides in the crude oil.

Water Degumming: Water degumming is suggested for refining crude oil with phosphorus content around 200ppm, such as soybean oil. The crude oil is firstly go through precipitatation by pure water hydration. Then gums are removed from the crude oil by using the principle of centrifugal separation. Water is the key agent in this degumming process. Below shows the flow diagram of water-degumming process of oil refining plant.

Acid degumming: Through acid conditioning process, gums are precipitated from the crude oil and then be removed by centrifugal separation. It is normally used in refining process of rice bran and sunflower oil.

Feel free to contact us if you are interested in detailed information about our refining solution of crude palm oil. We are always at your services!