Filtration process: Heat the crude oil and remove the foam in the oil by high-temperature stirring. Then add 0.1% to 0.2% phosphoric acid to the oil for stirring. The stirring time is controlled at about 30 minutes.

Alkali neutralization process: Mix 0.5% liquid caustic soda and 1.5% liquid soda ash with oil, and then refine it with alkali after mixing.

Sedimentation process: After the alkali neutralization reaction, heat the mixture to 50 to 52°C, stir again for about 10 minutes, stop stirring when the soap in the liquid is completely separated, and let it stand for 6 hours to separate the soap.

Water washing process: After separating the soap from the oil, heat it again and add a mixture of salt and alkali water at 90°C for 30 minutes to discharge the wastewater inside. Then add boiling water that accounts for 15% of the net oil content and let it stand again for processing and discharge the boiling water. The fat mechanical repeats these steps two or three times.

Decolorization process: Inhale the net oil after alkali refining and water washing into the pre-decolorization pot for pre-decolorization treatment. At this time, the vacuum degree should be controlled above 99kP, the temperature should be cooled to 70°C, and then sent into the pressure zone through the gear pump. filter for filtration.

Deodorization process: It is used to remove colored impurities in fats and oils through the combined action of direct steam and indirect steam.