Degumming is the first stage in the refining process. It is sued to separate the gums, phospholipids, proteins etc… that are insoluble in oil when hydrated. 

Salient features of the process are:
Crude oil is pumped continuously to an in line mixer where in pre-calculated quantity of water is added. Oil water mixture is fed to the hydration tank and allowed sufficient residence time for the gums to agglomerate on hydration and pumped to Separator where the oil and hydrated gums are separated and pumped to storage. Some particles that are not removed by water degumming need Acid Treatment.

Degummed oil from the separator is fed to a knife mixer, where it is intensively mixed with requisite quantity of concentrated phosphoric mixture and is allowed a brief holding time in the mixer and the precipitation of phosphatides and trace metals take place.