SC-CO fracturing technology is a feasible method for green extraction of unconventional oil and gas reservoirs. However, due to a series of problems such as sand transportation during SC-CO fracturing, CO thickening has become the focus of current research. Polymer thickeners have been widely used in oilfields. Due to the macroscopic nature and limitations of laboratory experiments, we have not been able to elucidate the microscopic mechanism of polymer thickening CO and the viscosity change of the CO fracturing fluid system downhole after polymer addition. In this study, we used all-atom modeling and molecular simulation of the COMPASSII force field. We selected nine polymers to study their microscopic properties and the factors affecting their effects. Finally, we simulated the viscosity change of the CO system after the addition of polymer tackifiers in the wellbore under the CO fracturing construction conditions by combining the data from one well in the oilfield.

中文翻译：

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井筒条件下超临界CO2压裂液中聚合物增粘剂的分子动力学研究


SC-CO压裂技术是非常规油气藏绿色开采的可行方法。但由于SC-CO压裂过程中的输砂等一系列问题，CO增稠成为当前研究的重点。聚合物增稠剂已广泛应用于油田。由于宏观性质和实验室实验的局限性，我们还无法阐明聚合物增稠CO的微观机制以及添加聚合物后井下CO压裂液体系粘度的变化。在这项研究中，我们使用了 COMPASSII 力场的全原子建模和分子模拟。我们选择了九种聚合物来研究它们的微观特性以及影响其效果的因素。最后，结合油田某井数据，模拟了CO压裂施工条件下井筒添加聚合物增粘剂后CO体系的粘度变化。