Pipeline ruptures have the potential to cause significant economic and environmental impact in a short period of time, and therefore it is critical for a pipeline operator to be able to timely detect ruptures and respond rapidly. Public stakeholder expectations are high and an evolving expectation is that the response to such an event be automated to the greatest extent possible, potentially initiating an automatic pipeline shutdown upon receipt of a system-based rupture alarm. These types of performance expectation are challenging to achieve with conventional, model-based, leak-detection systems (i.e. CPM-RTTMs) as the reliability measured in terms of the false alarm rate is typically too high to initiate automatic pipeline shutdowns.
Enbridge Pipelines Inc. (EPI) has been actively participating on an industry task force chaired by the API Cybernetics Committee, focused on the development of best practices in the area of Rupture Recognition and Response. After an industry release of the first version of a Rupture Recognition and Response guidance document, EPI has initiated development of its own internal Rupture Recognition Program (RRP) program. The RRP considers several rupture recognition approaches simultaneously, ranging from improvements to existing CPM leak detection to the development of new SCADA based rupture detection algorithms. This paper will provide an overview of the different rupture detection approaches, present some high level results and share learnings from work completed to date.
Most major liquid pipeline operators have a method of automatic leak detection monitoring and system alarming. Although those leak detection systems are able to detect ruptures the general low reliability of these systems in terms of their high frequency of false alarms (e.g. 1 or 2 false alarm a day for complicated long lines) may have played a role in some past rupture incidents. Those alarms may have caused controller desensitization and thereafter ignored or not given the appropriate attention.
Some pipeline industry experts are of the opinion that in the pursuit of detecting the smallest leaks, we may have become more exposed to the ruptures.