Method of efficiently separating solid fat from polyunsaturated fatty acid grease

A method of efficiently separating solid fat from polyunsaturated fatty acid grease, comprising the following steps:

• a) adding a small amount of inert solid powder to a heated melted polyunsaturated fatty acid grease, and stirring evenly, wherein the inert solid powder is selected from the group consisting of activated carbon, activated clay, diatomite and perlite, and wherein the polyunsaturated fatty acid grease is selected from the group consisting of fish oil, algal oil, linoleic acid, conjugated linoleic acid, linolenic acid and arachidonic acid;
• b) cooling and crystallizing the polyunsaturated fatty acid grease containing the inert solid powder obtained by step a) to a temperature of −10° C. to 5° C., to obtain a crystalline liquid;
• c) adding a certain amount of inert solid powder to the crystalline liquid obtained by step b), and stirring evenly, to obtain a solid-liquid mixture;
• d) filtering the solid-liquid mixture obtained by step c), to obtain a clarified polyunsaturated fatty acid grease and a filter cake;
• e) putting the filter cake obtained by step d) into a reactor and then heating to dissolve, to obtain a solid-liquid mixture containing the inert solid powder;
• and
• f) filtering the solid-liquid mixture obtained by step e), to obtain a solid fat filtrate in molten state and a filter cake containing the inert solid powder.