| The technology of polymer plug-removing to enhance the polymer injection is that analyzing the injury mechanism of polymer, the degree, the types and stating the problem of field test. Through the anlysis, we know that essential component of the plugging is the polymer, the mechanical impurity, organic clay, inorganic filthy, the organic dirt and mud and so on. At the same time, the polymer will produce certain injury to the core sample. The core permeability is lower, the injury degree is more serious. Along with the permeability increase, the injury degree will reduces.The principal constituent of the agent has better performance to the polymer. The polymer viscosity is smaller than 5.0mPa.s, the residual content is smaller than 50mg/L. The core sample expansion rate is smaller than 3%. The reacting system temperature achieves 90℃and emits 2000mL N2.The core experiment indicates that the differential pressure rises 1.27MPa and the permeability drops 0.332μm~2 after pouring into 1000mg/L polymer solution(2.38PV). After injecting 0.5% plug-removing agent solution(2.79PV), the differential pressure drops 0.026MPa, the core permeability restores 0.843μm~2, the injection pressure decline rate is 97.9% and the permeability restoration ratio is 94.3%.In the June, 2007 .we test 2 wells. The effectiveness is 100%. The average single well injection pressure drops 1.7MPa, the injection volume increased 52m3. For the 4 wells which connect with them, each oil well falls fluid 22m3, increases oil 3.0t, falls water cut 5.9 %, increases total oil above 1000t. The ratio of investment vs out is 1:3.2, obtaining better effection.
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