CFD Simulate And Design And Amplify Enzymatic Reactor For Solvent-free Through Esterification Reaction

Phytosterol can lower cholesterol and reduce the risk of cardiovascular disease.The state food and drug administration set it as a new resource food.In addition,phytosterol which as a broad application prospect of functional health products.However,the crystallization form of phytosterol in the body has the poor solubility and biological availability,so due to increasing the difficulty in the application in food.Phytosterol fatty acid ester is through homemade phytosterol and fatty acid and diatomite immobilized lipase in the laboratory catalyzing esterification,but in the reaction process,high the system viscosity and poor effectiveness in mixing and mass transferring,increasing the difficulty of the amplification reaction system.Therefore,using the computational fluid dynamics to simulate phytosterol and oleic acid of solvent-free esterification synthesis system,and finally through the simulation experiments to determine the correctness of the model.First,using CFD to simulate 5 L reaction system through method of multiple reference frame and laminar flow model,and invest some aspects,for instance,the viscosity,mixer type,air distributor,stirring speed and so on,and achieving results,such as the optimal mixing speed 200 rpm,the best ventilation rate 4.5 L/min,the optimum propeller for variable frame four oblique leaf blade-2,best air distributor is coiled round type,simulation system in stable viscosity viscosity 600 cp.Second,using the same modeling method to establish 30 L reaction system,300 L and 1 t system,getting the the optimum propeller for variable frame-six oblique leaf blade and ribbon-six oblique leaf blade.Finally,use experimental method.According to the substrate mole ratio of 4:1,adding 1335 g oleic acid,484 g phytosterols,and diatomite immobilized enzyme 18000 U/g,under water activity 15%rh,55°,Cafter 96 h reaction,protoplasmic type conversion rate was 55.2%,anchor-four oblique leaf blade conversion rate was 73.4%,and the optimum propeller variable frame four oblique leaf blade-2 conversion rate was 92.1%,which was 36.9%better than protoplasmic.to verified the correctness of the model.