Experimental Contrast of the Effective Viscosity Determination Methods of Binary Flooding System

For the development of oil and gas field, the effective viscosity determination of the viscoelastic fluid is always the problem of chemical flooding and there are technical problems to verify difficultly. The common methods include bulk phase viscosity method, the rheological curve method, and the drag coefficient method. This article tested and compared the methods respectively by adopting the binary system of fixed concentration. The results showed that using the method is more scientific that calculate the effective viscosity according to the curve transformation. The viscosity curve was obtained from the along sample tests in the long cores. For the experimental core with the length of 300mm and permeability of 2500×10-3μm, the average of the injection viscosity and the viscosity of produced liquid is closer to the effective viscosity of binary system in the core. Keywords-Offshore oil field; binary system; viscoelastic fluid; the effective viscosity; average viscosity method