Gas filled pipelines monitoring using multipoint vibroacoustic sensing

eni S.p.A. has promoted and supported a research project (DIONISIO) for the design of a proprietary pipeline monitoring system, exploiting negative pressure waves and statistical analysis principles. A discrete network of pressure and vibration sensors are installed on the pipeline, at relative distances of tens of kilometers. The acoustic and elastic waves produced by third party interference and by flow variations (leaks, spills, valve regulations, pig operations, etc.), propagate along the pipeline, and they are recorded at the monitoring stations. Multichannel processing of the collected signals enables the real time detection, localization and classification of the triggering event. The system has been tested in single phase and multiphase transportation lines during several field campaigns. This paper collects the results for gas transportation pipelines. The field experience has been used to upgrade the prototypal version of the system to an industrial version, that is currently operative, or in an advanced installation phase, on several pipelines in Italy and in Nigeria, and it has detected tens of bunkering activities with a localization accuracy of about 25 m, from a distance up to 35 km from the sensing point.