Flow Field Simulation And Structural Optimization Of A Continuous Polymerization Reactor

Materials with excellent properties can be prepared by polymerization reactions. The polymerization stirred tank for batch reactor is often used in industrial application. Because continuous polymerization reactor has the advantages of high production efficiency, large production capacity, stable product quality, etc., it has been widely used in the industrial application. But we must ensure the rapid mixing of polymerization monomer and catalyst, and the rapid withdrawal of polymerization reaction heat during its process. Therefore, it is necessary to optimize the structure of continuous polymerization reactor in order to provide design basis for industrial device.In this thesis, the flow and mixing process of butene-1 continuous polymerization reactor is simulated by using fluid dynamics software Fluent, and the flow field distribution in continuous operation is studied. By changing the number of blades, the combination of blades, the position and height of the heat exchanger, the rotate rate of blades, the internal structure of the mixing tank has been optimized. The average residence time, the number of virtual stirred tank and the average age distribution of the liquid in the stirred tank are obtained by simulating the residence time distribution and UDS respectively.The results show that simulation result of three layers of blades cannot meet the requirements for mixing. On the basis of the four layers of blades, the combination of 45° PBT and MKW with higher heat exchanger has the best mixing performance. The optimized stirred tank with mixing time decreasing significantly and the local circulation disappearing forms the connection flow in the whole tank. Increasing the rotate rate of blades can accelerate the circulation speed.