Applied Study Of New-type Polymer Hydrolyzation Mixer And Numerical Simulation Of The Non-Newtonian Fluid In A Stirred Tank

With the development of the study on polymer flooding technology,new-type of polymers are developed and applied. These polymers, which molecular weight is more than 2.5×107g/mol, are apt to form ultra-molecular structures in solution with pretty high viscosities. Conventional technics couldn't fit the need of new type polymers hydrolyzation quite well. In this paper a new type of industrial mixer is designed. We also finish the mixing fluid field 3-D simulation in it. Main contents are as follows.By means of measuring rheological property of UHMW-PAM solution, it is investigated that viscosity of PAM solution relates to concentration, temperature, molecular weight and shear rate. The higher concentration and molecular weight are, the bigger viscosity is. Increasing with the shear rate, polymer solution shows property of shear thinning. The relationship between viscosity of polymer solution and shear rate obey power-law. Viscosity decreases with increasing temperature.The results showed that the higher concentration is, the bigger first normal stress difference is. It means that solution has higher elastic energy. At the same shear rate, elasticity intensifies with polymer molecular weight increasing. Elasticity of polymer solution decreases with increasing temperature.Formula established on basis of experimental data about rheological property of PAM solution, provides warranty for modeling flowing of polymer solution.Structure and operation parameters of new type mixer designed for the polymer are optimized via small and industrial experiments. It can improve circulation of fluid field effectively and increase the homogenized rate. Consequently, it reduced curing time from 4h to 2h, the viscosity of polymer increased by 10%, however, mixing power has a little fall.The results of simulation show that there are two apparent opposite dead zone above and under blades. Deficiency of axial flow engenders a main circulation in stir red tank. The place far from blades flows weakly. While the flow near stir axial, tank and wall almost still.The new impeller makes polymer solution in tank form axial circulation, the flow shape is the key factor to increase the homogenized rate. Average viscosity is biggerthan that of double three-blade-inclined agitator. Velocity, shear rate and viscosity distribution are consistent with flow law. It is also in good agreement with experimental results given by literature and test.