低初始黏度可控凝胶调堵剂的研制及性能评价

Development and Evaluation of Performance for Low Initiation Viscosity Controllable Gel System

周 泉 李 萍 哈俊达 王 力 吕 杭

ZHOU Quan LI Ping HA Junda WANG Li LV Hang

为了满足聚合物驱后深部定点调堵的需求，进一步挖潜剩余油，研发了一种以相对分子质量2500万的部分水解的阴离子型聚合物、金属离子交联剂、调节剂、缓凝剂、增强剂组合的低初始黏度可控凝胶调堵剂体系，对其性能进行了评价。研究结果表明：用现场回注污水配制的配方为500~1000 mg/L聚合物LH2500+1000~2500mg/L交联剂CYJL+200~500 mg/L调节剂（柠檬酸）+100~150 mg/L缓凝剂（亚硫酸钠）+100~200 mg/L增强剂（多聚磷酸钠）的凝胶初始黏度低，在10 mPa·s以内；成胶时间10~40 d内可控，成胶黏度2000 mPa·s以上。体系耐矿化度可达20000 mg/L，应用pH范围为8~9；体系具有较好的岩心封堵性能，对水测渗透率为0.48~3.9μm2的岩心封堵率均在99%以上，残余阻力系数为95.6~396.1。三层并联岩心实验结果表明该体系对中、低渗透层的污染少，可以满足现场的封堵要求。图2表7参10

With the end of the block of polymer flooding area or the late effect，the dominant percolation channel is more prominent， and the difficulty of effective mining is increased. In view of the demand for fixed plugging in the deep fixed point after polymer flooding，in order to further tap the remaining oil and reduce the ineffective circulation of the injecting fluid in the process of production and development after polymer flooding，a low initial viscosity controllable gel plugging agent，composed of hydrolyzed anionic polymer with molecular weight of 25 million，metalion crosslinker，regulator，retarder，strengthening agent，was developed，and the performance of gel plugging agent system was evaluated. The results showed that the formulation of the system prepared with reclaimed wastewater was as follows，500—1000 mg/L polymer LH2500+1000—2500 mg/L cross-linking agent CYJL+200—500 mg/L regulator（citric acid）+ 100—150 mg/L retarder（sodiumsulfite）+ 100—200 mg/L enhancing agent（polyphosphate sodium），the initial viscosity of the system was low，being of within 10 mPa·s，and the gelation time was controllable within 10—30 days，and the gelling viscosity was above 2000 mPa·s. the tolerance to salinity was up to 20000 mg/L，and the suitable pH range was 8—9. The system has better core plugging performance，the blocking rate of the system to the core with the permeability of 0.48—3.9 μm2 was more than 99%，and the residual resistance factors was in range of 95.6—396.1.The results of the three-layer parallel core experiments indicated that the system had less pollution to the mid-low permeability core，meeting the in-sit plugging demand.

10.19346/j.cnki.1000-4092.2019.02.010