Experimental and Numerical Research of Cottonseed Flour and Meal Extrusion Detoxification
|School||Beijing University of Chemical Technology|
|Course||Chemical Process Equipment|
|Keywords||Cottonseed Cottonseed meal Screw extruder Detoxification Flow field Simulation Control volume method|
This article is the first time the use of self-developed visual natural polymer with a single, twin-screw extruder, using statistical means of experimental design and data analysis, a more detailed study of the cottonseed meal extrusion detoxification process and device parameters detoxification effect. In addition, the paper's first to use protein material constitutive equation control volume method of experimental group members established empirical formula of single screw extruder such a high moisture content, high viscosity materials flow field numerical simulation to discuss the different flow model and process parameters on the extrusion process. The The squeeze the detoxification test results show that the screw extrusion virus-free, simple, and can obtain good detoxification effect, but need a good match between the extrusion parameters. Moreover, single-and twin-screw extruder and cottonseed meal, cottonseed meal detoxification law there are also significant differences. Kneading disks added to reduce the content of free gossypol in cottonseed meal, but it should be appropriately placed, the the kneading disks length, position and role of the interaction is very significant, and the pitch was not significant. In addition, the kneading disk parameters detoxification effect also exists a certain extent. From the organizational structure of the extruded products, despite the difference can be extruded cottonseed protein with soy protein extruded products similar to the fiber structure of the organization; the actual extrusion detoxification, free gossypol may be the same variety of amino acids its salts chemical reaction occurs and the existence of a plurality of reaction sites, lysine is one of the important reaction component. The extrusion flow field simulation results show that the machining parameters affect cottonseed meal extrusion process, the moisture content of most significantly, the screw speed, followed, and there was an interaction between the two: dimensionless yield major impact along the flow velocity distribution morphology, and little impact on other quantities: the viscosity on the cross section of the spiral groove along the spiral groove depth direction was near the wall, the distribution characteristics of the intermediate position. Constitutive equation is to decide these extrusion key factor in the response variable reaction. Cottonseed meal is a natural polymer materials, extrusion modified constitutive equation is very complex. The empirical formula for the calculation of the simulation experiment of its group members protein material constitutive relation, the results also show that the different flow model treatment is not the same as the results obtained. Newtonian fluid handling numerical differences with non-Newtonian fluid, but also reflect the approximate extrusion processing of the actual situation; non-Newtonian and non-isothermal and temperature along the flow of the full development situation then there is a variable significantly from the initial fluctuations to gradually stabilized, and finally with the full development of the situation consistent development process. From virus-free results, the screw extruder detoxification method is effective and worthy of further research and application; From the numerical simulation results, the calculation method used in this paper, the treatment program is successful.