Study On Viscosity Reducing Device For Improving The Polymerization Applicability Of Hydrocyclone

With the gradual increase of water cut in oil field,secondary and tertiary oil recovery techniques have appeared successively.Among them,tertiary oil recovery technology improves oil production and has been widely used through alkali-surfactant-polymer flooding.Hydrocyclone is widely used in petrochemical industry due to its advantages of small volume,large capacity and high separation efficiency.The use of polymer flooding technology has changed the rheological properties of the treatment solution,increased the viscosity of water phase,not only made the pumping rod and other force conditions more complex,but also reduced the separation performance of the hydrocyclone.It increases the difficulty of treatment of produced fluid and surface sewage in oil field.In order to explore the influence of polymer content on the rheological properties of the medium,the rheological analysis experiments of polymer solution with different concentration were carried out by rheometer in this paper,and the rule of the influence of polymer concentration on the rheological property of the medium was grasped.The changes of the viscosity,shear stress and shear rate of the polymer solution at different concentrations,as well as the consistency coefficient and the rheological behavior index of different concentration of polymer solutions,were obtained.The influence of viscosity of continuous phase on the velocity field,pressure field,oil phase volume fraction and separation efficiency of hydrocyclone is studied by means of numerical simulation of Newtonian fluid according to the influence of different viscosity conditions on the hydrocyclone flow field.The critical value of the effect of viscosity on the efficiency of hydrocyclone is obtained.Based on the mechanism of physical shearing,a mechanical viscous reduction device was proposed,and the structural parameters were designed.The structural parameters of the viscosity reducing device are optimized by using the mean viscosity at the outlet of the viscosity reducing device as the output index by the orthogonal test method.Using non-Newtonian fluid numerical simulation method and rheological parameters obtained from rheological measurements,the effects of polymer concentration on the separation performance of hydrocyclone and the evaluation of viscosity reduction effect of viscosity reduction device were studied.In order to ensure the accuracy of the study,an integrated fluid domain model for the assembly of viscosity reduction device and hydrocyclone was constructed.The flow field characteristics and separation efficiency were simulated and analyzed by non-Newtonian fluid numerical simulation method.Study on separation performance of hydrocyclone after series viscosity reduction device.The experimental system is constructed to carry out the experimental verification.The experimental results are in good agreement with the numerical simulation results,which verifies the feasibility of the mechanical viscosity reduction device and the accuracy of numerical simulation.