Detecting Small Leaks in Liquid Pipelines
The increase in operation of existing pipeline infrastructure near sensitive environmental regions and urban centers has driven a renewed focus on the detection of small leaks in hazardous liquid pipelines. The predominant method for detecting leaks in liquid pipelines in North America is through computational pipeline monitoring. While these algorithmic systems have many years of performance data, they are not suited, in some cases, to detect small releases without the generation of numerous false alarms. PRCI has sponsored a six-year-long program to address the gaps in technology for detecting small leaks in hazardous liquid pipelines. This work has evolved over several projects from a paper study to laboratory testing to full-scale testing on an operational pipeline. The objectives of this work are to gather data on the suitability of such systems for detecting small leaks and to refine knowledge gaps on the applications of various technologies. During the program, analysis was conducted for distributed temperature sensing (DTS) technologies to evaluate system performance over a range of conditions, including batch product flow and diurnal temperature changes. Laboratory testing was also conducted on several different DTS technologies. The testing characterized the performance of such systems as functions of wetted length, spatial resolution, and total fiber length. Acoustic leak detection technology was first vetted by creating dynamic hydraulic models to determine propagation and attenuation of negative-pressure waves induced by leaks. This information was fed into a full-scale field testing effort in which several commercially-available technologies were tested on an active crude pipeline. This work on detecting small leaks in hazardous liquid pipelines has highlighted the value in complimentary technologies for leak detection and provided data on their performance envelope. This multi-year effort has also demonstrated how collaboration amongst stakeholders from many different operational perspectives can result in driving technological innovation to strengthen pipeline safety.