Study On Two Phase Flow Characteristics In A Self-Stirring Reactor Driven By Pressure Energy

Stirred reactor is one of the important equipment in the hydrometallurgical industry,which is almost used in each process of hydrometallurgy.Centering on the energy saving,heat transfer,mass transfer and chemical reaction enhancement and inhibition of scab,a new pressurized reactor-pressure-driven self-stirred reactor was developed by our research group.As the two phase flow characteristic and the relationship between stirring speed and original power-pressure energy are unclear,in this paper,from two aspects of physical simulation and numerical simulation,the two phase flow in the new stirred reactor was studied,which laid the foundation for the further development of the reactor.In this paper,aiming at the pressure-driven self-stirred reactor,based on the previous research,the commercial CFD software FLUENT15.0 and parallel computing system graphics workstation were used to study the solid-liquid two phase flow systematically.The main results are as follows.1.PIV technology and numerical simulation were applied to study the water phase flow behaviors.The results showed that the distribution of velocity in the reactor was uniform.The increase of inlet pressure and liquid level was conductive to the uniform distribution of fluid velocity and the increase of inlet pressure can also reduce the dead zone until it disappeared.2.The solid-liquid two phase flow was researched by combining the particle concentration measurement technology and numerical simulation.It was concluded that the increase of stirring speed was beneficial to the uniform distribution of particles,but near the stirring shaft,over-high speed led to the decrease of particle concentration under the centrifugal force.The decrease of particle diameter and solid concentration is beneficial to the uniform distribution of particles in the reactor.The critical just-suspended impeller speed decreased with the decrease of particle diameter and increased with the increase of solid concentration.3.The optimal operation conditions obtained by numerical simulation were:stirring speed was 150rpm,initial solid concentration was 15%and particle diameter was 75?m.Based on the suspension theory,the predicted behaviors and phenomenon obtained by numerical simulation were explained reasonably.The optimal operation parameters were predicted and the basic data of the fluid dynamic characteristics was acquired,which laid the foundation for the further development of the reactor.