Predictive Technique Study Of Development Index With Polymer Flooding

Polymer flooding is that adding certain quantity of water-soluble polymer into injected water to increase the viscosity of water phase, simultaneously reduce the permeability of water phase, improve the mobility ratio, and enlarge the swept volume, so as to enhance the macroscopic recovery efficiency of crude oil; recent studies show that the microscopic morphology of irreducible oil, after water flooding, can be categorized into oil droplet, oil film, cluster-type and blind-type residual oil. Polymer has viscoelasticity, so the force flooding residual oil is different from that of Newton fluid, the force flooding residual oil has some differences with that of Newton fluid, not only capillary pressure perpendicular water-oil interface, that overcomes residual oil, but also stronger motivating force, parallelled water-oil interface, that drives residual oil, so it also enhances the microscopic oil displacement efficiency. Polymer flooding has came into the phase of industrialization application in Daqing oil flied, the indexes prediction of polymer flooding development play an important role in program development. Basing on the mechanism of polymer flooding, the performance characteristics of polymer flooding and the variable characteristics of the development index of polymer flooding, it's predicted the development indexes of polymer flooding and sequential water flooding after polymer flooding by the use of the experience method. By means of the real data of the polymer applied tracts in Daqing oil field, we studied the relations among cumulative liquid production, cumulative water production, cumulative oil production, water cut and time in different coordinate system, concluding cumulative liquid production, cumulative water production, cumulative oil production, water cut with time changing law. We define experimental formula by regressing. We predict further development index basing on experimental formula. In this predictive method, formula is simple, calculated amount is small, and calculated velocity is fast.