» Refining

Degumming

Physical Refining

Remove gums in oil with special degumming method. FFA in oil is removed with steam. Features:

1. high oil refining ratio, less oil loss;
2. No waste water discharged;
3. More FFA distilled out;
4. Especially suitable for oils of high acid value, and low gum content;

Chemical Refining

Neutralize FFA in the oil with alkali. The gum and soap produced are centrifuges. Features:

1. less requirements to crude oils;
2. the finished oil is more consistent in quality;
3. Less bleaching earth used compared with physical refining;

Bleaching

Add bleaching earth into the degummed oil. Under vacuum state, the oil is continuously mixed with bleaching earth in the Continuous Bleacher, where main part of colour bodies as well as oxidizing materials in the oil are absorbed by the bleaching earth. After Continuous Bleacher, the oil/clay mixture is passed through Leaf Filters where the spent earth is removed together with the precipitated materials from degumming. The oil then passes through one of two alternatively working safety filters before entering the next section.

Deeaxing/Winterizing

De-waxing system plays an important role in improving palatability, transparency and brightness of oils. The wax content is different in various oils. For maize oil, rice bran oil, sunflower seed oil, cottonseed oil etc. de-waxing is very important. The de-waxing methods are freezing, surface active agents, cold polymerizer, electrostatic, and winterizing etc. Currently winterizing method is most popular. The crystallizing temperature, crystallizing velocity, and crystal maturating time and filtering mode vary with oils.

Winterizing/Dewaxing