井筒泄漏问题是石油工业面临的关键挑战,限制钻井进度和增加钻井成本。封堵剂在修复渗漏和骨折方面发挥作用;然而,传统的堵漏材料一般机械强度低,对透水地层适应性差,有限的吸水和膨胀能力,耐温性和耐盐性差。为了解决这些限制,本研究通过水溶液聚合合成了一种开创性的聚丙烯酸-聚丙烯酰胺(PAA/PAM)双网络水凝胶。它的力量,吸水,扩展,耐温性,耐盐性,并对封堵效果进行了综合评价。结果表明,合成的水凝胶具有良好的机械性能,能够在90%应变下承受约3.5MPa的最大应力。在合成的双网络水凝胶中观察到优异的吸水性和膨胀性,30min内最大膨胀6倍,2h后最大膨胀8倍。保持强度等级E在实验范围内。封堵实验的模拟评价表明,在130°C和6MPa的条件下,当使用双网络水凝胶时,钻井液的泄漏率保持在5mL/min以下。从以上实验结果来看,可以说明,优异的机械性能,令人印象深刻的吸水性,合成的双网络水凝胶表现出膨胀能力。此外,还证明了双网络水凝胶的耐高温性和耐盐性。因此,与传统的堵漏材料相比,这种新合成的双网络水凝胶材料作为钻井液中的堵漏剂具有重要的前景。
The problem of wellbore leakage is a key challenge in the petroleum industry, limiting drilling progress and increasing drilling costs. Plugging agents play a role in repairing leaks and fractures; however, traditional plugging materials generally have low mechanical strength, poor adaptability to permeable strata, limited water absorption and expansion capabilities, and poor temperature and salt resistance. To address these limitations, a pioneering polyacrylic acid-polyacrylamide (PAA/PAM) double-network hydrogel was synthesized through aqueous solution polymerization in this study. Its strength, water absorption, expansion, temperature resistance, salt resistance, and plugging effectiveness were comprehensively evaluated. The results demonstrate that good mechanical performance is exhibited by the synthesized hydrogel, capable of withstanding a maximum stress of approximately 3.5 MPa at a 90% strain. Excellent water absorption and expansion are observed in the synthesized double-network hydrogel, with a maximum expansion of 6 times within 30 min and 8 times after 2 h. Test results show that the hydrogel had good temperature resistance and salt resistance, maintaining a strength grade E within the experimental range. The simulated evaluation of the plugging experiment indicates that, under conditions of 130 °C and 6 MPa, the leakage rate of the drilling fluid is maintained below 5 mL/min when the double-network hydrogel is utilized. From the above experimental results, it can be illustrated that excellent mechanical properties, impressive water absorption, and expansion capabilities are exhibited by the synthesized double-network hydrogel. Furthermore, the high-temperature resistance and salt resistance of the double-network hydrogel were also demonstrated. Therefore, In comparison to traditional plugging materials, significant promise is held by this newly synthesized double-network hydrogel material as a plugging agent in drilling fluids.