Physical refining process
Oil physical refining process, also called as oil steam refining. During the degumming section in the cooking oil refining plant. the gum will be removed from palm oil by utilizing phosphoric acid or citric acid. Next to bleaching section, the coloring matter and other metal ions will be absorbed or removed. Then, in the deacidification and and deodorization section, the crude cooking oil will be processed within low pressure and high temperature. Through live stem, the FFA will be stripped of and the odors and colors will be removed or absorbed.
 

Chemical refining process:
During the cooking oil chemical refining process, the FFA will be removed and the neutralized crude cooking oil and soap stock will be produced. And the soap stock will be separated from cooking oil by using of high-speed separator. And the color pigments and the metal ions will be removed from the neutralized oil. If the crude cooking  oil contains high carotene, high FFA (more than 5% ) and relative low phosphatides, it will be great to have the chemical refining process to reduce the refining losses and the operation costs.