大庆油田杏六区块东部聚合物驱试井分析

对大庆油田杏六区东部区块聚驱条件下含水率、产液量等动态参数的变化规律进行了综合评价.同时结合生产井实例对杏六区聚合物驱试井曲线的变化特征进行分析.结果表明:注聚合物后地层渗透率降低,渗流阻力增大,注采压差增大;各注聚试验区虽然注入压力有较大幅度的增加,而生产井流动压力却有不同程度的下降,含水率下降,产液量上升;根据试井解释时采用的油藏模型,可以判断在聚合物驱油过程中,油藏模型由均质油藏变化为复合油藏再变化为均质油藏,或由均质油藏变为均质加边界油藏再变化为均质油藏;为防止聚合物突破时间过快,可在聚合物驱油初期对地层进行适当调剖,避免油藏过早达到均质油藏阶段,这有利于提高中低渗透层的出油潜力,有效提高原油采收率.

Well testing analysis of polymer flooding in the east of Xing-6 block of Daqing Oilfield

The varying laws of water cut and liquid producing amount in the polymer flooding in the east of Xing-6 block are evaluated. The characteristics of well testing curves of the polymer flooding in the block are analyzed by cases. It is shown that,after polymer flooding,the formation permeability decreases,seepage resistance increases,and therefore injection-production pressure difference increases; although the injection pressure greatly increases in every polymer injection test areas,the flow pressure and water cut of production wells decreases in different degrees,and their liquid producing amount also increases; in polymer flooding process,it is judged according to the reservoir model used in the well testing interpretation whether the reservoir model changes from heterogeneous reservoir firstly to composite reservoir and then to heterogeneous reservoir,or firstly to homogenous adding boundary reservoir and then to heterogeneous reservoir; in order to prevent too early breakthrough in polymer flooding,appropriate profile control can be carried out in the early stage of polymer flooding to avoid to early reaching to heterogeneous reservoir stage,which is favorable to improve the oil potential of the medium-low permeability layers and to effectively enhance oil recovery factor.