基于主客体识别作用的油藏深部调剖体系

Deep Profile Control System Based on Host-guest Molecular Recognition Principle

邵明鲁 左姜 赵红雨 常爱莲 李晓骁 浮历沛 廖凯丽

SHAO Minglu ZUO Jiang ZHAO Hongyu CHANG Ailian LI Xiaoxiao FU Lipei LIAO Kaili

油藏深部调剖作为一类改善开采效果、提高采收率的重要技术，已广泛应用于非均质油藏水窜治理。为改 善水窜治理过程中调剖剂注入性与深部封堵这一矛盾，基于主客体识别作用，提出自组装深部封堵技术。首先， 以丙烯酰胺、N，N'-亚甲基双丙烯酰胺、烯丙基-β-环糊精和苯乙烯为原料，通过乳液聚合法制得粒径为170 nm、表 面含有β-环糊精基团的主体纳米颗粒；然后，以十六烷基二甲基烯丙基氯化铵和丙烯酰胺为原料，通过可控自由 基聚合法制得数均分子量低于4000、分子量分布为1.1～1.4 的客体聚合物。通过主体纳米颗粒和客体聚合物， 构筑具有自组装性能的调剖体系。通过调剖体系的黏度来评价纳米颗粒与聚合物的自组装性能；通过岩心驱替 实验，评价了调剖体系的注入-封堵性能。结果表明，由于客体聚合物分子中的疏水烷基链与主体纳米颗粒表面 的β-环糊精基团具有主客体识别作用，β-环糊精基团包合疏水烷基链形成包合物，客体聚合物发挥“桥连”作用， 纳米颗粒自组装聚集形成团粒簇，使调剖体系黏度缓慢增至约90 mPa·s。0.1%纳米颗粒与0.2%聚合物组成的 调剖体系的注入性良好，阻力系数为2.0；待自组装后进行后续水驱，残余阻力系数为3.42，封堵率为70.7%。该 研究为缓解调剖剂注入性与深部封堵的矛盾提供了新的思路。

Deep profile control，as an important technology to improve recovery，has been widely used for water channeling treatment in inhomogeneous reservoirs. In order to solve the contradiction between the injectivity of profile control agent and its in-depth plugging in the process of water channeling treatment，the self-assembled deep plugging technology was proposed based on the host-guest molecular recognition principle. Firstly，the host nanoparticles with a particle size of 170 nm and surface containing β-cyclodextrin group were prepared by emulsion polymerization using acrylamide，N，N'-methylene-diacrylamide，allyl group-β-cyclodextrin，and styrene as raw materials. Then，the guest polymers with a molecular weight below 4000 and a molecular weight distribution between 1.1 and 1.4 were prepared by controlled radical polymerization using cetyldimethyl allyl ammonium chloride and acrylamide as raw materials. The self-assembled profile control system was constructed by host nanoparticles and guest polymers. The self-assembly properties of nanoparticles and polymers were evaluated by the viscosity of self-assembled profile control system. Based on core displacement experiments，the injection-plugging performance of self-assembled profile control system was evaluated. The results showed that due to the host-guest recognition between the hydrophobic alkyl chain in guest polymer molecule and the β-cyclodextrin group on the surface of host nanoparticles，the β-cyclodextrin group encapsulated the hydrophobic alkyl chain to form an inclusion complex，while the guest polymer played a“bridge”role. The nano-particles self-assembled and aggregated to form clusters，which slowly increased the viscosity of profile control system to about 90 mPa·s. The injection performance of profile control system consisting of 0.1% nanoparticles and 0.2% polymer was good，with a resistance coefficient of 2.0. After self-assembly，subsequent water flooding was carried out，with a residual resistance coefficient of 3.42 and a plugging rate of 70.7%. This study provided a new approach to alleviate the contradiction between injectivity and in-depth plugging of profile control agents.

10.19346/j.cnki.1000-4092.2024.01.006