The performance of injected kinetic hydrate inhibitor (KHI) polymer solutions can be boosted considerably by judicious choice of the polymer solvent system. We report the excellent KHI synergism of the low-foaming acetylenic diol gemini surfactant 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) with poly(N-vinyl caprolactam), N-vinyl caprolactam:N-vinyl pyrrolidone copolymer, and poly(N-isopropylmethacrylamide). High-pressure rocking cell tests, using the slow constant cooling method or the isothermal method, were carried out with a natural gas mixture giving structure II hydrates as the preferred thermodynamically stable phase. Poly(oxyethylene) derivatives of TMDD, which are far more water-soluble than TMDD, gave significantly lower synergetic KHI performance with the same polymers. It is conjectured that the low aqueous solubility of TMDD (1700 ppm at 20 °C) and its two isobutyl groups are key features contributing to the synergism. However, when decane was added to the system as a model liquid hydrocarbon phase, the synergetic performance decreases, probably due to partitioning of TMDD to the hydrocarbon phase. This highlights the need to choose synergist systems which are retained in the aqueous phase for optimal performance when condensate or oil is present in the produced fluids. Optimizing the structure and aqueous solubility of the synergist (solvent or otherwise) can be seen as complementary to the known principle of optimizing the structure and solubility of the KHI polymer.

中文翻译：

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乙炔二醇表面活性剂与动力学水合物抑制剂聚合物的强大协同作用——选择正确的协同剂水溶解度

通过明智地选择聚合物溶剂系统，可以显着提高注射动力学水合物抑制剂 (KHI) 聚合物溶液的性能。我们报告了低泡炔二醇双子表面活性剂 2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) 与聚（N-乙烯基己内酰胺）、N-乙烯基己内酰胺的优异 KHI 协同作用: N-乙烯基吡咯烷酮共聚物，和聚( N-异丙基甲基丙烯酰胺）。使用缓慢恒定冷却方法或等温方法的高压摇摆电池测试是用天然气混合物进行的，给出结构 II 水合物作为优选的热力学稳定相。TMDD 的聚（氧乙烯）衍生物比 TMDD 更易溶于水，与相同的聚合物相比，其协同 KHI 性能显着降低。据推测，TMDD 的低水溶性（20°C 时为 1700 ppm）及其两个异丁基是促成协同作用的关键特征。然而，当癸烷作为模型液态烃相加入系统时，协同性能下降，可能是由于 TMDD 分配到烃相。这突出表明需要选择保留在水相中的增效剂系统，以便在采出液中存在凝析油或油时获得最佳性能。优化增效剂（溶剂或其他）的结构和水溶性可以看作是对优化 KHI 聚合物结构和溶解度的已知原理的补充。