Multi-stage molecular distillation continuous depickling technique for oil and fat with high acidity number

Abstract

The invention discloses a high acid-value grease depickling novel technology. The technology of the invention applies advanced molecular distillation technique to high acid-value grease depickling and can separate the grease from the fatty acid better on the basis of not damaging the original compositions of the raw material so as to reduce the oil acid-value; furthermore, the depickling effect can be improved by multi-stage serial connection and the continuous operation can be carried out. The acidified oil is dehydrated by fine filtration, saturated NaCl water washing and film braising and is pumped into a first-stage molecular distiller by a first-stage delivery pump so as to distil part of fatty acid; the distilled residue in the first-stage is taken as the raw material of the second-stage molecular distiller and pumped into the second-stage molecular distiller by a second-stage delivery pump so as to distil the residual fatty acid; the distilled residue is taken as the raw material of the third-stage; the circulation is repeatedly to the required N-stage; wherein, N is more than or equal to 2 and less than or equal to 5; the best stage number is 3 or 2. The technology of the invention has the advantages that the fatty acid is separated; meanwhile, the raw material composition of the grease is not damaged; the distilled high-quality fatty acid has extremely high application value by the further disposal; furthermore, multi-stage molecular distilling is beneficial to the continuous operation so as to complement the shortages of single-stage separation capability, thus providing beneficial conditions for the industrialization in large scale.

Description

technical field [0001] The invention relates to a new process for deacidifying oil with high acid value. The process applies advanced molecular distillation technology to the deacidification of acidified oil with high acid value. The acid value can also obtain fatty acids with higher purity, and can improve the removal effect and realize continuous operation through multi-stage series distillation. Background technique [0002] Due to the influence of the environment, its own moisture, and lipase during the collection, storage and transportation of oil, it will be hydrolyzed to generate a large amount of free fatty acids (FFA), which will cause its acid value to rise and eventually form rancid oil, such as high water content, Vegetable oil with strong lipase activity and gutter oil with harsh environment. [0003] For the treatment of these high-acid oils, the commonly used methods are chemical alkali refining and steam stripping for deacidification. For oils with high aci...

AI Technical Summary

Problems solved by technology

For oils with high acid value, the amount of alkali used in chemical alkali refining is large, and the alkali also saponifies a large amount of neutral oil during the neutralization process with free fatty acids, resulting in a low refining yield; physical refining steam stripping Acid and oil need to be processed at high temperature for a long time, which affects the quality of the oil. The color of the product is darker. Some active ingredients in the oil, such as V E and sterols will overflow with steam stripping, for V-rich oil like wheat germ oil E For fats and oils, the nutritional and health value is reduced

Other treatment methods include solvent extraction, supercritical CO 2 Extraction, esterification or membrane separation, etc., but there are also problems such as low efficiency, high cost or immature technology

Images