Study On Hydrodynamic Characteristics Of High Viscosity Horizontal Double-shaft Devotilization Reactor

The devolatilization process is a key step in the production process of polycarbonate(PC),and the mass transfer process is enhanced by removing volatiles.This article is based on the devolatilization process in the PC production process,based on an efficient horizontal devolatilization reactor,using different sizes of star-shaped propellers and hollow disk propellers to explore different operating conditions,physical properties and structural conditions.The fluid mechanics characteristics of the reactor change law,and the relevant parameters are dimensionlessly fitted,and the power standard and the dimensionless film thickness are predicted.At the same time,XFlow software was used to establish a CFD simulation method for a high-viscosity horizontal twin-shaft devolatilization reactor,and the power characteristics,flow field characteristics and film formation characteristics in the reactor were explored,which is the design of the high-viscosity horizontal twin-shaft devolatilization reactor.,Amplification and optimization provide basic data.The experimental results show that:1.The flow pattern of the materials in the double-shaft horizontal stirred tank is Stewartson flow pattern.2.The performance indicators of the reactor(power,liquid holding capacity and film thickness)are related to the direction of rotation of the stirring shaft,and are positively related to varying degrees of conditions such as the number of blades,rotation speed,material viscosity,and liquid level.3.The enlargement of the reactor size will not change the flow pattern in the reactor,and the power consumption has a large increase in multiples.4.The use of back rotation,the blades have a more symmetrical structure,providing more support,and adding scrapers are the optimization directions of the reactor.5.The simulation results using the lattice Boltzmann method are in good agreement with the experimental results.6.The velocity field,pressure field and surface renewal rate distribution are all related to the steering of the stirring paddle,and it is better to adopt the backward rotation method.