Performance of vibroacoustic technology for pipeline leak detection

Integrity and operational reliability of pipelines requires a continuous monitoring, able to detect, in real time, failure, sabotage and leak of fluids (e.g. natural gas, crude oil, water, products), and to protect the safety of personnel and local communities. In the framework of a research project, eni has developed a proprietary pipeline monitoring technology based on vibroacoustic (negative pressure wave) sensing. This paper presents some experimental and theoretical activities for the evaluation of the system performance versus fluid leaks, in terms of maximum detection distance and sensitivity. The field scenario is a 12 km, 3 inch inner diameter sealine in south of Italy, conveying a fluxing agent from an onshore terminal to an offshore platform. Leak-like events have been produced by opening discharge valves at the terminals. The associated travelling pressure transient, recorded by several monitoring stations, has been compared with the environmental noise (generated by the flow regulation equipment) and with the theoretical models. The predicted propagation parameters and maximum detection distance are in very good agreement with the measured ones: this allows us to use the theoretical simulator for design and performance evaluation of new installations.