Method for extraction of unsaturated fatty acid from oil-containing microalgae and preparation of aviation fuels

Abstract

The invention provides a method for extraction of unsaturated fatty acid from oil-containing microalgae and preparation of aviation fuels. The method includes: 1) subjecting microalgae to crushing and wall breaking to obtain microalgal powder particles and adding an entrainer, extracting the unsaturated fatty acid in the microalgal powder particles by a supercritical CO2 extraction technique to obtain mixed oil and algal residue; 2) conducting separation and enrichment on the mixed oil extracted in step 1) to obtain unsaturated fatty acid and residual oil; and 3) performing thermal cracking on the algal residue obtained in step 1) to obtain pyrolytic bio-oil, then mixing the pyrolytic bio-oil with the residual oil, and performing a hydrogenation treatment to obtain a kerosene-containing main product and a byproduct containing gasoline and diesel. According to the method, the unsaturated fatty acid extraction rate can reach 80-95%, and the total extraction rate of oil is 70-90%. The obtained kerosene ingredient can reach the standard of aviation kerosene.

Description

technical field [0001] The invention relates to the field of comprehensive utilization of oil-containing microalgae, in particular to the pyrolysis of remaining oil and residual residue after extraction including but not limited to polyunsaturated fatty acids DHA (docosahexaenoic acid) / EPA (eicosapentaenoic acid) A method for producing aviation kerosene through co-hydrogenation and isomerization of bio-oil, and by-product gasoline and diesel. Background technique [0002] Compared with other energy plants, microalgae have become the main biological raw materials for alternative energy due to the characteristics of high photosynthetic efficiency, high oil yield, no occupation of cultivated land, and no collection of food from people. In addition, algae cells also contain a large amount of polyunsaturated fatty acid nutrients that can reduce high blood pressure and heart disease, which lays the foundation for the development of multi-effect utilization of microalgae. [0003]...

AI Technical Summary

Problems solved by technology

[0006] Although oleaginous microalgae have multiple uses, currently the use of microalgae is limited to a certain aspect, or only extract unsaturated fatty acids from microalgae as health products, or only extract oil to prepare biofuels, or directly pyrolyze to prepare biofuels

Moreover, although bio-aviation fuel bears the dual responsibilities of energy security and carbon emission reduction, there are still many technical obstacles to the commercialization of microalgae biofuels

The reason, first, is mainly due to the low comprehensive utilization efficiency of algal substances in the actual operation process, which leads to high production costs and other problems

Therefore, it is urgent to provide a new technology for the comprehensive utilization of algal substances to solve the problems in the above existing technologies and industrialization; second, the bio-oil obtained by direct pyrolysis has the disadvantages of low calorific value, high acidity, and poor stability. The introduction of catalysts can effectively improve the quality of oil products, and the catalytic pyrolysis efficiency of microalgae needs to be further improved; thirdly, the algae oil obtained through conventional preparation processes is far from meeting the requirements of aviation kerosene. In addition to the differences in composition and existing aviation kerosene, its viscosity , surface tension, stability, low-temperature performance and other indicators are far from reaching the aviation kerosene index, that is, it is necessary to design feasible hydrofining and hydroisomerization cracking processes to meet or approach the aviation oil standard

Fourth, the cost of preparing aviation kerosene from microalgae is high, and industrial applications are limited

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