Approach to Assess the Effectiveness of Isolation Valves as Part of Pipeline Risk Assessment

Abstract Valves are installed on pipelines to help reduce the amount of product that can be released in the event of a pipeline loss of containment. Valves can be closed both up- and downstream of the release location to limit the amount of product that can drain out of the pipeline under gravity. Often operators perform assessments to understand the optimal locations to place valves or to assess the optimal valve type to use. This is done for pipelines currently operating and new pipelines being planned. This paper discusses an approach using similar tools, which have been adapted to assess the effectiveness of existing valves. It includes details on how this information can be analyzed and applied to improve pipeline risk assessments and integrity management programs. This approach was recently applied to a large North American pipeline, which has been used as case study for this paper. The pipeline covers over 1,000 kilometers and has over 100 valves across several distinct pump sections. The valves are a mixture of manually operated, remotely operated, and check valves. The effectiveness of each valve at reducing potential release volumes was assessed by excluding each valve individually and comparing release volumes with and without that valve. Release volumes were modeled as hypothetical full-bore rupture releases at a maximum of 30-meter intervals along the full length of the pipeline segment. This paper covers the details of this approach as well as provides a summary of some of the key findings. This analysis results in a large amount of data that can be difficult to assimilate into the decision-making process. An interactive data insights dashboard can be a useful tool to quickly filter, summarize, and analyze each valve. This tool can be used to filter by pump section or individual valve, see how the release volumes change along that pipeline segment based on each valve, and see summary statistics for each scenario. Lastly, this tool can be useful to understand what portion of the pipeline segment is affected by each valve. Lastly, this paper will review how these data insights can be used to improve pipeline risk assessments and pipeline integrity management. The result of this analysis specifically feeds into the optimization of an equipment failure risk model which helps to reduce risk by focusing on valves with higher probabilities of failure or those with significant consequences in case of failure. Valve effectiveness analysis for each pipeline pump section also enables the operator to develop effective emergency response plans and mitigation strategies.