深海输油管线选择性自填充亲油拒蜡表面的构建与应用研究

Surface modification of pipe wall to regulate the wettability of crude and wax is a promising method to solve the wax deposition problem in submarine oil transportation. Therefore, the proper design and construction of anti-waxing surface on pipe wall is a key science to avoid wax deposition in oil transportation. It was reported that partially cross-linked polymers can be selectively swollen by low molecular weight components in the crude oil and forms slippery anti-waxing surface, which prevents the adhesion and accumulation of wax crystalline. Based on the reported works, this project combines more closely with the oil transportation application. By adjusting the preparation process, the controllable preparation method of slippery anti-waxing surface is established. By characterizing the swelling thermodynamic properties and wax crystallization kinetics on slippery anti-waxing surface, the anti-waxing mechanism is revealed and the design criteria is determined. The influences of transportation pressure, flow velocity and temperature on the anti-waxing effect is determined by flow loop test to determine the proper working conditions for the slippery anti-waxing surface. The robustness of the slippery anti-waxing surface against eroding, transportation shut down and sea water corrosion is tested to provide evidence for engineering applications. The research finds of this project will provide theoretical basis and technical support for the construction and application of slippery anti-waxing surface.

对原油管线内表面进行表面改性，调控其对原油和蜡质的润湿性，可有效改善深海原油输运中的蜡沉积现象。合理设计与构建具有特殊润湿性的拒蜡表面是原油管道防蜡沉积的关键科学问题之一。已有研究报道，部分交联的聚合物层可选择性溶胀原油中的低分子量组分，形成超滑表面（slippery surface），阻挡蜡分子附着和生长。在已有报道基础上，本项目紧密结合原油特性，通过调节制备工艺，掌握超滑拒蜡表面的可控构建方法；通过表征超滑表面的溶胀热力学特性和蜡分子在其表面的结晶动力学特性，揭示超滑表面的拒蜡机理，提出超滑拒蜡表面的设计依据；利用原油输运环道试验，分析输运压力、流速、温度对超滑表面拒蜡效果的影响规律，确定适合超滑拒蜡表面服役的工况条件；测试拒蜡表面耐冲刷、耐停输、耐海水腐蚀等鲁棒性能，为工程应用提供依据。本项目实施所取得的研究成果，将为石油管线超滑拒蜡表面的设计构建和工程应用提供理论基础和技术支持。

防污自清洁涂层在石油、化工、矿山领域有着广泛的应用背景，现有自清洁涂层通常采用仿生设计，如仿荷叶的微凸体结构以及仿猪笼草的液体浸润多孔结构，上述涂层仍存在微结构易损伤、浸润液体易流失等不足。本项目研究了新结构防污涂层的制备方法，探索了涂层在石油、矿山等领域的防污性能和机制，为自清洁涂层设计和制备提供新的思路。.首先，项目研究了自修复防污复合涂层的制备工艺，将猪笼草和荷叶结构复合，底层聚合物起到了储存润滑介质、促进变形的作用；表面颗粒则形成了微-纳双级粗糙结构。其次，项目研究了耐磨凹坑结构防污涂层制备工艺，通过生物模板转印和常温CVD生长制备了带有凹坑和凸起粗糙峰的双重结构自清洁涂层，显著提升了涂层的耐磨性。第三，项目开展了凝胶涂层以及基于界面滑移聚合物涂层的制备研究。通过高聚物溶胀制备了防石蜡粘附凝胶涂层，该涂层通过隔绝熔融石蜡与固体表面的直接接触，降低了石蜡接触面积和形核率，获得了粘附强度约为5.2KPa的弱粘附表面。进一步研究表明，将液体状态的溶胀剂替换为低聚物材料可制备允许界面滑移的高弹态涂层，在保持较低的石蜡粘附力的同时，显著提升了涂层的鲁棒性。第四，项目利用单步溶胶凝胶法制备了具有纳米颗粒和低表面能特性的疏水亲油涂层，制备涂层后金属滤网的油水分离率达到92%以上。第五，利用解析算法研究了涂层/基体体系在摩擦磨损时的应力场，研究发现硬质涂层可能导致材料体系抵抗塑性变形能力反而下降，并首次利用球形纳米压痕实验直接验证了上述效应，为涂层优化设计提供了理论依据。该项目的开展为仿生自清洁涂层的设计和制备提出了新的结构和方法，为自清洁涂层在石油、矿山等领域的应用提供了基础性实验依据和理论分析。