基于幂律流体模型的渤海油田注聚管柱注入能力分析

Injection capacity analysis of downhole polymer injection pipe string in Bohai oilfield based on power law fluid model

考虑聚合物溶液的非牛顿性和海上注聚管柱的特点,提出了油管注聚和环空注聚情况下聚合物溶液摩阻计算方法,利用此方法对渤海S油田注聚井段进行了相关计算,指出了该油田注聚管柱中流体摩阻较大的管柱,并通过分析不同管柱和流体组合情况,指出了不同日注聚量情况下应采用的注聚管柱。在此基础上,对渤海S油田注聚井最大井口注入压力进行了计算,结果表明该油田注聚井大部分注聚段在400 m3/d注入量时井口注入压力有0.5~1.5 MPa提升空间,在600 m3/d注入量时井口注入压力有1~3 MPa提升空间。建议海上油田注聚井实行"一井一策"精细化压力管理,避免统一限定注入压力上限带来的不利限制。

Considering the characteristics of non-Newtonian polymer solution and downhole polymer injection pipe string,methods to calculate polymer solution friction of both tubing and annulus are put forward. Based on these methods,fluid friction of all polymer injection wells in Bohai S oilfield is calculated and the wells with high fluid friction are singled out. Through comprehensive analysis of the combination of different pipe strings and fluids,the corresponding pipe strings for different injection rates are given out. The maximum wellhead injection pressures of polymer injection wells in Bohai S oilfield are calculated and results show that the wellhead pressure can be increased by 0. 5 to 1. 5 MPa at an injection rate of 400 m3/d and 1 to 3 MPa at an injection rate of 600 m3/d for most polymer injection wells. The polymer injection wells in offshore oilfields are suggested to adopt fine pressure management of ＂one well one policy＂to avoid the unfavorable restriction of uniform upper limit of injection pressure.