Establishment and Application of Flow Field Evaluation System after Early Polymer Injection in Thick Reservoir

Abstract

In view of the problem that it is difficult to further improve the recovery rate of offshore thick reservoir after long-term polymer injection and water injection, the distribution of underground reservoir flow field is studied. Taking Bohai L oilfield as the research object, various indexes describing the reservoir flow field are selected, the flow field strength is calculated by analytic hierarchy process and fuzzy evaluation method, and the comprehensive evaluation system of flow field is established. The feasibility of the evaluation method is verified by the mechanism model. It is applied in Bohai S oilfield. The flow field distribution and potential tapping area are defined. The adjustment wells are added in the weak flow field area, and the profile control is strengthened in the strong flow field area to optimize the water injection measures. The daily oil increase is 300 m³/d, the cumulative oil increase is 5×10⁴ m³, and the potential tapping effect is better.