Flow Characteristics Of High Watercut Produced Liquid With Polymers

As the oil fields in the east part of China entered the later period, the water cut of the produced liquids increased extremely. And with the wide use of polymer flooding technology, large amount of polymers are found in the produced liquids. Those two factors above cause great differences in the flow characteristics of the produced liquids compared to the traditional oil-water two phase flow. Therefore the research of super high water cut produced liquids with polymers has a great value to the efficient operation of the gathering lines and the production safety of the oil field.In this passage, an temperature controlled oil-water two phase flow experimental system is proposed. The system can implement different working conditions conveniently and mix water and crude oil reasonably below the condensation point of the oil. The flow characteristics of polymer solution and super high water cut produced liquids with polymers are studied by changing oil concentrations, temperatures, velocities and polymer concentrations.The experimental results of polymer solution showed: the pressure drop gradient first decreased then increased with the rise of polymer concentration, the minimum pressure drop point would move backwards with the decrease of velocity and rise of temperature; the polymer had a drag reduction property in a certain range of concentrations and velocities, the drag reduction efficiency increased with the rise of velocity, the maximum drag reduction point would move backwards with the decrease of velocity and rise of temperature. The experimental results of super high water cut produced liquid showed: the pressure drop gradient increased with rise of the mix velocity and oil concentration, decreased with the rise of temperature, and first decreased then increased with the rise of polymer concentration; the mix viscosity decreased with the rise of velocity which showed an apparent property of shear thinning and increased with the rise of oil concentration, apart from conditions of high oil concentrations and low velocities, the mix viscosity first decreased then increased with the rise of polymer concentration.Based on Homogeneous flow model, Power-Law fluid model and analysis of the experimental data, two mix viscosity prediction models of super high water cut produced liquids were proposed. A mix viscosity calculation software which is convenient to use in oil field is written.