大庆中低渗油层聚合物溶液注入性和驱油性能分析  

Analysis on Injectivity and Displacement Property of Polymer Solution in Low-Middle Layers of Daqing Oil Field

作　　者：张立娟[1,2] 岳湘安[1,2] 王楠[1,2] 

机构地区：[1]石油工程教育部重点实验室(中国石油大学),北京昌平102249 [2]中国石油大学提高采收率研究中心,北京昌平102249

出　　处：《油田化学》2008年第3期235-240,共6页Oilfield Chemistry

基　　金：国家重点基础研究发展计划(973计划)"化学驱和微生物驱提高石油采收率的基础研究"(项目编号2005CB221300);国家自然科学基金项目"聚合物溶液微尺度流动探索研究"(项目编号50574060)

摘　　要：采用标准岩心和多测点岩心,通过室内的岩心流动和驱替实验研究了相对分子质量1.0×107、浓度500 mg/L、750 mg/L和1000 mg/L的聚合物溶液在大庆中低渗油层的注入性和驱油性能。考察了流速对注入压力动态的影响和压力的沿程变化。通过引入当量PV数将物模岩心实验的线性流动转换为油藏的径向流动,对聚合物溶液在油藏各处的压力动态进行了预测。对比分析了不同浓度聚合物溶液的阻力系数动态分布和采出液流变性的变化。研究结果表明,聚合物溶液在油藏中的实际工作黏度是决定大庆中低渗油藏注聚效果的关键因素,近井地带聚合物溶液的黏度损耗最为严重。流速过高和近井地带堵塞会带来注入压力过高,聚合物溶液不吸入等问题。On artificial standard cores and long cores with mutiple measuring points, laboratory experiments are carried out for the injectivity and the oil displacement capability of 500, 750, and 1000 mg/L polymer solutions under simulation conditions of tertiarymain layers in North Saertu reservoirs in Daqing. The polymer used has molar mass 1.0 × 10^7 and degree of hydrolysis 23 %. Mainly investigated characteristic is the dynamic injection pressure as influenced by flow rate and the pressure varying along the flow stream in cores. A new term, equivatent volume injected in PV, is introduced to convert the linear flow rate determined in core flow experiments to a radical flow rate existed in reservoirs and by this way the dynamic polymer solution pressure at different points of a reservoir is predicted. The resistance factor varying along the flow stream in cores and created by polymer solutions of different concentration and the viscosity of the polymer solutions flown out of the cores axe analyzed comparatively. It is shown by experimental results that the effective, working, viscosity of the polymer solution in place is the key, determinative factor for its displacement efficiancy in the aimed reservoir layers. The greatest viscosity losses of the injected polymer solutions are observed in near bore zones of injection wells. Extra high flow rate and blockage in near bore zones might cause abnormal high injection pressure or zero injection of plymer solutions.

关 键 词：低渗透油藏 聚合物驱 剪切降解 注入能力 驱油性能 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程] TE39