Abstract Leak detection in pipelines has been a prevalent issue for several decades. Pipeline leaks from sources such as small cracks and pinholes are termed chronic leaks, as they have the potential of going unnoticed for long time periods, causing both economic losses and environmental damage. Literature lacks a comprehensive review of chronic leaks, especially under subsea or arctic conditions. Therefore, a primary objective of this work was the critical analysis of the current state of leak detection technology, especially under these conditions. A summary of critical findings from both experimental and field studies is included. A secondary goal was to determine the leak detection accuracy, resource level requirements, and risk of installation and operation for various techniques. The analysis shows medium to large scale leaks between 3 and 10 mm can be detected using dynamic pressure wave monitoring for single phase flow, whereas sequential probability ratio testing (SPRT) using real time transient monitoring (RTTM) can be used to monitor leaks for multiphase flow even in shallow water conditions and along elevated pipeline networks. Vacuum annulus monitoring arrangements can be utilized in order to detect chronic leaks, but are limited in their application due to weight and difficulty of pipeline installation. Additionally, distributed temperature sensing (DTS) and distributed acoustic sensing (DAS) leak detection using fiber optic cables (FOC) was found to be resource intensive and have higher installation cost and operational risks due to unknown equipment reliability and location or sealing of the FOC on the pipeline structure. SPRT using RTTM have comparable accuracy to DTS or DAS leak detection and can be retrofitted to existing pipeline networks. However, more pilot studies utilizing FOC for subsea and arctic conditions need to be developed and examined. Leak detection using new pipeline construction materials such as reinforced thermoplastics (RTP) also warrant further research due to a current lack of reliable technology for these materials.

中文翻译：

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单相和多相流的慢性泄漏检测：对陆上和海上海底和北极条件的批判性审查

摘要 几十年来，管道中的泄漏检测一直是一个普遍存在的问题。来自小裂缝和针孔等来源的管道泄漏被称为慢性泄漏，因为它们有可能在很长一段时间内被忽视，造成经济损失和环境破坏。文献缺乏对慢性泄漏的全面回顾，尤其是在海底或北极条件下。因此，这项工作的主要目标是对泄漏检测技术的当前状态进行批判性分析，尤其是在这些条件下。包括对实验和实地研究的重要发现的总结。第二个目标是确定各种技术的泄漏检测精度、资源水平要求以及安装和操作的风险。分析表明，使用动态压力波监测单相流可以检测 3 到 10 毫米之间的大中型泄漏，而使用实时瞬态监测 (RTTM) 的顺序概率比测试 (SPRT) 可用于监测多相流的泄漏。即使在浅水条件下和沿高架管网流动。真空环空监测装置可用于检测慢性泄漏，但由于管道安装的重量和难度，其应用受到限制。此外，使用光纤电缆 (FOC) 的分布式温度传感 (DTS) 和分布式声学传感 (DAS) 泄漏检测被发现是资源密集型的，并且由于未知的设备可靠性和 FOC 在 FOC 上的位置或密封而具有更高的安装成本和操作风险管道结构。使用 RTTM 的 SPRT 具有与 DTS 或 DAS 泄漏检测相当的准确性，并且可以改装到现有的管道网络中。然而，需要开发和检查更多利用 FOC 在海底和北极条件下进行的试点研究。由于目前缺乏针对这些材料的可靠技术，因此使用增强型热塑性塑料 (RTP) 等新型管道结构材料进行泄漏检测也值得进一步研究。使用 RTTM 的 SPRT 具有与 DTS 或 DAS 泄漏检测相当的准确性，并且可以改装到现有的管道网络中。然而，需要开发和检查更多利用 FOC 在海底和北极条件下进行的试点研究。由于目前缺乏针对这些材料的可靠技术，因此使用增强型热塑性塑料 (RTP) 等新型管道结构材料进行泄漏检测也值得进一步研究。使用 RTTM 的 SPRT 具有与 DTS 或 DAS 泄漏检测相当的准确性，并且可以改装到现有的管道网络中。然而，需要开发和检查更多利用 FOC 在海底和北极条件下进行的试点研究。由于目前缺乏针对这些材料的可靠技术，因此使用增强型热塑性塑料 (RTP) 等新型管道结构材料进行泄漏检测也值得进一步研究。