聚合物弱凝胶在高盐中低渗条件下的渗流特性及影响因素  

Seepage Characteristics and Influencing Factors of Polymer Weak Gel under High Salinity,Medium and Low Permeability Conditions

作　　者：张楠[1] 卢祥国[1] 谢坤[1] 郐婧文 杨海恩[2] 何治武[2] 任建科[2] 吴浩[3] ZHANG Nan;LU Xiangguo;XIE Kun;KUAI Jingwen;YANG Hai’en;HE Zhiwu;REN Jianke;WU Hao(Key Laboratory of Enhanced Oil and Gas Recovery(Ministry of Education),Northeast Petroleum University,Daqing,Heilongjiang 163318,P R of China;Oil and Gas Technology Research Institute,Changqing Oilfield Company,PetroChina,Xi’an,Shaanxi 710021,P R of China;Underground Operation Branch,Daqing Oilfield Company,Ltd,Daqing,Heilongjiang 163318,P R of China)

机构地区：[1]提高油气采收率教育部重点实验室(东北石油大学),黑龙江大庆163318 [2]中国石油长庆油田公司油气工艺研究院,陕西西安710021 [3]大庆油田有限责任公司井下作业分公司,黑龙江大庆163318

出　　处：《油田化学》2020年第2期254-259,共6页Oilfield Chemistry

基　　金：十三五国家科技重大专项“渤海双高油田多级窜逸堵调驱一体化技术研究及示范”(项目编号2016ZX05058-003-010);国家自然科学基金项目“抗盐型聚合物油藏适应性及其改进方法基础研究”(项目编号51574086);中国石油天然气股份有限公司科学研究与技术开发项目“长庆油田勘探开发关键技术研究与应用”(项目编号2019-4156)。

摘　　要：为提高长庆高盐油藏采收率,以长庆油田油藏地质特征和流体性质为模拟对象,研究了聚合物弱凝胶的渗流特性及影响因素,分析了作用机理。结果表明,影响聚合物弱凝胶渗流特性的因素较多。随聚合物浓度、相对分子质量、注入水矿化度和Cr^(3+)浓度增加,聚合物弱凝胶的阻力系数(Fr)和残余阻力系数(F(rr))增大,驱替过程中注入压力增加;随岩心渗透率减小,Fr和F(rr)增加,注入压力增加。不同类型聚合物交联生成的弱凝胶对岩心的封堵效果不同。与相同浓度的聚合物溶液相比,尽管聚合物弱凝胶视黏度略为减小,但其Fr和F(rr)较大,且F(rr)大于Fr,液流转向能力良好。水稀释引起弱凝胶分子链舒展和吸水水化膨胀是造成弱凝胶分子聚集体尺寸增大、岩心孔隙内滞留和封堵作用增强的主要原因。图6表9参25。In order to improve the recovery factor of Changqing high-salinity oil reservoir,the seepage characteristics and influencing factors of polymer weak gel were studied,and the action mechanism was analyzed basing on the geological characteristics and fluid properties of Changqing oilfield.The results showed that there were many factors influencing the seepage characteristics of polymer weak gel.With the increase of polymer concentration,relative molecular mass,injection water salinity and Cr3+concentration,the drag coefficient(Fr)and residual resistance coefficient(Frr)of polymer weak gel increased,and the injection pressure increased.As the core permeability decreased,the Fr and Frr increased,and the injection pressure increased.Weak gels formed by different types of polymers had different blocking effects on the core.Although the apparent viscosity of polymer weak gel was lower than that of polymer solution at the same concentration,the Fr and Frr of polymer weak gel were larger.Moreover,the Frr was greater than Fr,which indicated excellent flow steering ability.The main reason for the increase in the size of weak gel molecular aggregate was molecular chain stretching and water swelling of weak gel as a result of water dilution,which led to enhanced retention and plugging in the core.

关 键 词：高盐 中低渗 聚丙烯酰胺 弱凝胶 渗流特性 影响因素 

分 类 号：TE357.46[石油与天然气工程—油气田开发工程]