Study on Polymer Flooding Injection Method

With the deepening of the understanding of polymer flooding development, the injection allocation design of single well polymer flooding is very important. At present, there are few studies on the rational injection allocation method in the early stage of various reservoir polymer flooding, and the calculation method of injection allocation during water flooding development is still used. Field application shows that the method only considers geological factors, and does not consider the influence of inaccessible pore volume, system resistance coefficient and injection velocity on expanding swept volume and improving oil displacement efficiency. Therefore, the design results have little guiding significance for the development of polymer flooding stage, and a series of problems such as plane, interlayer and intra layer contradictions and injection-production imbalance are soon exposed. In this paper, the inadaptability of the previous injection method is analyzed, and the influence of geological conditions, resistance coefficient of injection system, inaccessible pore volume and injection velocity on injection in single well of rational polymer flooding is studied. Through the study of theory and practice, the injection distribution method suitable for the polymer flooding in Lamadian oilfield is determined to improve the expanded swept volume and oil displacement efficiency of various reservoir polymer flooding, so as to enhance the recovery efficiency.