Tian Yuexin, Liu Xiangjun, Liu Yintao, Dong Haifeng, Zhang Guodong, Su Biao, Liu Xiaofeng, Hu Yifan, Huang Jinjun, Lu Zeze
Petroleum Engineering Technology Institute of Southwest Petroleum Branch, SINOPEC, Deyang 618000, China.
State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China.
Molecules. 2024 Dec 17;29(24):5950. doi: 10.3390/molecules29245950.
Wellbore instability caused by hydration during the development of shale gas reservoirs poses significant challenges to drilling engineering. In this study, a novel and environmentally friendly shale inhibitor, TIL-NH, was synthesized via free radical polymerization using 1-vinylimidazole and N-(2-bromoethyl)-1,3-propanediamine dihydrobromide as the main raw materials. The molecular structure of TIL-NH was characterized by infrared spectroscopy and nuclear magnetic resonance. Incorporating imidazole cations and amino bifunctional groups, TIL-NH exhibits excellent inhibitory performance and environmental friendliness. Its performance was systematically evaluated through linear swelling tests, shale cuttings rolling recovery tests, permeability recovery experiments, and dynamic adsorption analyses. The results indicate the following: (1) At a concentration of 1.2 wt%, TIL-NH reduced the linear swelling height of shale by 65.69%, significantly outperforming traditional inhibitors like KCl and NW-1. (2) Under conditions of 140 °C, the cuttings rolling recovery rate of TIL-NH reached 88.12%, demonstrating excellent high-temperature resistance. (3) Permeability recovery experiments showed that at a concentration of 2.0 wt%, TIL-NH achieved a permeability recovery rate of 90.58%, effectively mitigating formation damage. (4) Dynamic adsorption experiments indicated that at a concentration of 2.5 wt%, the adsorption capacity tended toward saturation, reaching 26.00 mg/g, demonstrating stable adsorption capability. Additionally, environmental friendliness evaluations revealed that TIL-NH has a degradation rate exceeding 90% within 28 days, and its acute toxicity is significantly lower than that of traditional inhibitors like KCl (the LC of TIL-NH is 1080.3 mg/L, whereas KCl is only 385.4 mg/L). This research provides a high-efficiency and environmentally friendly new inhibitor for green drilling fluid systems in horizontal shale gas wells, offering important references for technological advancements in unconventional energy development.
页岩气藏开发过程中因水化作用导致的井壁失稳给钻井工程带来了巨大挑战。本研究以1-乙烯基咪唑和N-(2-溴乙基)-1,3-丙二胺二氢溴酸盐为主要原料，通过自由基聚合反应合成了一种新型环保页岩抑制剂TIL-NH。采用红外光谱和核磁共振对TIL-NH的分子结构进行了表征。TIL-NH含有咪唑阳离子和氨基双官能团，具有优异的抑制性能和环境友好性。通过线性膨胀试验、页岩屑滚动回收率试验、渗透率恢复实验和动态吸附分析对其性能进行了系统评价。结果表明：(1)在浓度为1.2 wt%时，TIL-NH使页岩的线性膨胀高度降低了65.69%，显著优于KCl和NW-1等传统抑制剂。(2)在140℃条件下，TIL-NH的岩屑滚动回收率达到88.12%，表现出优异的抗高温性能。(3)渗透率恢复实验表明，在浓度为2.0 wt%时，TIL-NH的渗透率恢复率达到90.58%，有效减轻了地层损害。(4)动态吸附实验表明，在浓度为2.5 wt%时，吸附量趋于饱和，达到26.00 mg/g，表现出稳定的吸附能力。此外，环境友好性评价显示，TIL-NH在28天内的降解率超过90%，其急性毒性显著低于KCl等传统抑制剂（TIL-NH的LC为1080.3 mg/L，而KCl仅为385.4 mg/L）。本研究为水平页岩气井绿色钻井液体系提供了一种高效环保的新型抑制剂，为非常规能源开发的技术进步提供了重要参考。
