橡胶粉掺杂热塑性柔性颗粒调剖堵水剂

Rubber Powder Doped Thermoplastic Flexible Particle Plugging Agent

杨祖国 席玲慧 郭继香 薛 艳 李 亮 李生林

YANG Zuguo XI Linghui GUO Jixiang XUE Yan LI Liang LI Shenglin

油田长期注水开发导致油井含水率高，需要开发环保、低成本、优质高效的油田化学调剖堵水剂。以聚乙烯醇（PVA）、橡胶粉、戊二醛和自制疏水改性剂为原料，制备了可在水相中一次成型的热塑性柔性颗粒调堵剂。分析了调堵剂的粒径和微观结构，通过质构评价方法评价了调堵剂的力学性能，在高矿化度水和120～200 ℃条件下考察了调堵剂的稳定性，采用全贯穿裂缝模型研究了调堵剂在裂缝中的注入、运移和封堵效果。结果表明，橡胶粉与PVA质量比为0～1.75时可制得优势粒径为10～20目（2.00～0.85 mm）的毫米级柔性颗粒，大大降低合成成本。与未添加橡胶粉的颗粒相比，橡胶粉掺杂的柔性颗粒具有疏松多孔的结构和更高的热稳定性与力学性能。失重温度由 200 ℃提升至 300 ℃，硬度由 18.73 N增至 37.31 N，弹性从 0.86 增至 0.99，回复性由 0.48 增至0.60，咀嚼性由15.39 N增至35.88 N。柔性颗粒在高温和高矿化度水中保持稳定，120 ℃下老化60 d的力学性能不受影响，颗粒老化3 d后出现粘连聚集，具有良好的热塑性。物模实验结果表明，橡胶粉掺杂的柔性颗粒能形成稳定的压差波动，可迅速适应裂缝的变形和压力变化，且能形成有效封堵，封堵率为85.7%。橡胶粉掺杂的柔性颗粒具有良好的形变能力、热稳定性和注入性能，可用于改善高含水油田中深部液流转向的问题，提高油藏的采收率。

Long-term water injection in oilfields leads to high water cut in oil wells，necessitating the development of environmentally friendly，low-cost，high-quality，and efficient chemical agents for profile adjustment and water shutoff. Using polyvinyl alcohol （PVA），rubber powder，glutaraldehyde，and a self-prepared hydrophobic modifier as raw materials，a thermoplastic flexible particle profile adjustment and water shutoff agent that could be formed in one step in aqueous phase was prepared. The particle size and microstructure of the profile modification and water shut-off agent were analyzed，and then its mechanical properties were evaluated using texture analysis method. The stability of the agent was examined under the conditions of high-salinity water and temperatures ranging from 120 ℃ to 200 ℃. A full-penetration fracture model was used to investigate the injection，transport and blockage effects of the agent in fractures. The results showed that when the mass ratio of rubber powder and PVA was between 0 and 1.75，flexible particles with an advantageous particle size of 10—20 mesh（2.00—0.85 mm）could be prepared，significantly reducing synthesis costs. Compared to particles without rubber powder，the rubber powder-doped flexible particles exhibited a loose and porous structure，higher thermal stability，and better mechanical properties. The weight loss temperature increased from 200 ℃ to 300 ℃，the hardness increased from 18.73 N to 37.31 N，the elasticity increased from 0.86 to 0.99，the resilience increased from 0.48 to 0.60，and then the chewiness increased from 15.39 N to 35.88 N. The flexible particles remained stable in high-temperature and high-salinity water，without impact on mechanical properties after aging 60 days at 120 ℃. The particles exhibited good thermoplasticity，beginning to adhere together after aging 3 days. Physical model experiments demonstrated that rubber powder-doped flexible particles could form stable pressure fluctuations，quickly adapt to fracture deformation and pressure changes，and effectively block fractures，with a blockage efficiency of 85.7%. The rubber powder-doped flexible particles possessed excellent deformability，thermal stability and injectivity，which were suitable for improving deep liquid flow redirection in high water cut oilfields and enhancing oil recovery.

10.19346/j.cnki.1000-4092.2025.01.013