Abstract:

The efficient and safe exploitation of offshore oil and gas fields is a necessary means to practice the national deep sea strategy and explore the future strategic energy sources. Plugging of multi-phase mixed transportation pipelines operating at low temperature and high pressure in deep water has become an urgent problem for safe production and flow assurance in energy industry, and the rapid formation of natural gas hydrate is the main trigger for this problem. To clarify the mechanism of hydrate slurry plugging in oil-water system, to develop green and environment-friendly low-dosage hydrate inhibitor, and to master the multi-phase flow characteristics of slurry will provide theoretical basis and technical guidance for multi-phase mixed transportation flow assurance in deep-water oil fields. To this end, this paper summarizes and outlines the research progress of flow assurance of hydrate slurry in oil-water system from the aspects of hydrate plugging mechanism, chemical methods to prevent and control hydrate plugging, and flow characteristics of hydrate slurry; it should further quantify the effect of these factors on flow resistance and pipe blockage, and establish a theoretical system for assessing the risk of hydrate blockage in industrial pipelines. With the aid of microscale experiments and molecular dynamics simulations, it will clarify the inhibition mechanism of different types of KHIs and the anti-agglomeration mechanism of AAs. It is also proposed that combining experimental exploration, theoretical analysis and numerical simulation, the coupling relationship between particle microscopic behavior and macroscopic physical parameters of flow field is analyzed to quantitatively characterize slurry rheology and flow resistance.

Key words: oil-water system, flow assurance, hydrate formation, hydrate inhibitors, flow characteristic

摘要：

海洋油气田的高效、安全开采是践行国家深海战略、探索未来战略能源的必要手段。在深海低温、高压环境下运行的多相混输管道的堵塞已成为能源行业安全生产和流动保障的棘手问题，而天然气水合物的快速形成是造成这一问题的主要诱因。明晰油水体系水合物浆液的堵塞机理，开发设计绿色、环保的低剂量水合物抑制剂，掌握浆液的流动特征，将为深水油田多相混输管道的流动保障提供理论基础和技术指导。为此，本文从水合物堵塞过程、化学法防治以及水合物浆液的流动特性等方面总结概括了油水体系水合物浆液的流动保障研究进展。油水体系水合物堵塞主要由水合物的生长、聚集、管壁黏附和着床沉积造成，文章提出：应量化水合物生长、聚集、管壁黏附和着床沉积等因素对流动阻力和管道堵塞的影响，建立科学的工业管道水合物堵塞风险评估理论体系；借助微观尺度实验和分子动力学模拟，厘清不同类型的动力学抑制剂（KHIs）抑制机理和防聚剂（AAs）防聚机理；将实验探索、理论分析和数值模拟相结合，解耦颗粒微观行为与流场宏观物理参数间的关系，定量表征浆液流变性和流动阻力。

关键词: 油水体系, 流动保障, 水合物形成, 水合物抑制剂, 流动特性