Study On Inflow Performance Characteristics Of Wells For Polymer Flooding Reserviors

Polymer flooding has been increasingly used in Enhanced Oil Recovery, unlike water flooding, polymer solution is a kind of non-Newtonian fluid, This dissertation has conducted the research focusing on well inflow performance of polymer flooding, there is vital significance for designing the reasonable production system and making well working system.Firstly, this paper systematically and deeply studied the seepage features and rheological behavior of formation fluid under the condition of polymer flooding, considering factors such as the moisture content、rheological behavior 、the solubility of polymer solution and viscoelastic of polymer solution, established composite model of formation fluid effective viscosity, The relationship between consistency coefficient and rheological behavior index and the solubility of polymer solution under different temperature was determined by the rheological test;Secondly, around the seepage characteristic of formation fluid in the process of polymer flooding, and considering the change of formation permeability and the viscoelasticity of polymer solution, regarding the change of pressure and production as a definite condition, the well productivity prediction model of polymer flooding is build, and discuss the sensitivity of capacity. We analyzed the flow characteristic under different conditions by displacement experiments;Then, according to the mass conservation equation, momentum conservation law and darcy’s law, the mathematical model of polymer flooding is established;Finally, The article established 27 models under the Stars model of the CMG numerical reservoir simulators, considering the reservoir fluid property parameters(oil and water relative permeability data, oil-water viscosity ratio, water content), geological factors(permeability, reservoir thickness, reservoir area, porosity, anisotropy), the nature of the polymer solution itself(such as solubility, viscosity, maximum adsorption quantity, and pore volume, residual resistance coefficient) effect on polymer flooding well inflow performance, the IPR curve of the all models in accordance with the Vogel dimensionless processing, using Origin software, a large number of nonlinear fitting regression was obtained, and this article get the new dimensionless IPR curve under the different recovery degree, in combination with one well production decline analysis of shengli oilfield, The results show that the general formula can effectively predict well inflow performance of polymer flooding, dimensionless inflow performance and the result of sensitivity analysis can provide theoretical basis for polymer flooding field development practices.