How Effective LDAR Campaigns Contribute to Minimizing Methane Emissions

Abstract According to the IEA, the oil & gas industry can achieve a 75% reduction in methane emissions with current technologies, and up to 70% at no net cost. About 62% of the emissions CO2e is coming from upstream activities. Fugitive emissions constitute the biggest single emitting source. LDAR is therefore essential in every upstream asset. In this paper, I will discuss best practices and share case studies about how LDAR can help to minimize methane emissions. Leak Detection and Repair programs have a long history with EPA Method 21 or OGI. LDAR is crucial to prioritize maintenance activities. Although some gas companies prefer OGI because of cost reasons, the more effective detection technique for all methane emissions is still using sniffing equipment PID or FID. A comparative study indicated that only 71% of the bigger leaks with more than 262 kg/year emissions are found with OGI and only 5% of the smaller leaks. Moreover, quantification of the mass leaks becomes much more accurate with sniffing equipment compared to camera screening combined with leak/no leak factors. A best in class approach is realized with an LDAR campaign that applies Risk-Based Inspection considerations in combining measuring techniques like FID/PID and OGI and frequencies referring to the probability of occurrence and consequence of emissions (source type, historical performance, stream composition, HAP, …). Another best in class practice is situated around repair activities. While in every campaign between 10 to 20% new leaks are identified, 80 to 90% of the emitting sources were leaking in previous measuring surveys and have returned. The tightening of leaking gaskets and seals provides a temporary better emission value of more than 90% reduction in only 62% of the repair attempts. Although a typical emission reduction improvement with a thorough LDAR program of 70% is achievable, more emphasis should go to in-depth problem solving to avoid recurring leaking sources. Examples include proactive mass replacement of certain gaskets or stem valve seals during turnaround activities. This continuous improvement realized with these repair activities decreases the fugitive emissions steadily. Situations, where a yearly LDAR campaign has been omitted, demonstrate a quick return to past emission figures. Executing LDAR, finetuned to the situation and outstanding legislation, is necessary to contribute to lower methane and in general GHG emissions. Based on our experience of delivering successful Leak Detection & Repair (LDAR) in the past three (3) decades, we would like to share new technologies & approaches towards detection, quantification and reduction of Methane losses, that are being implemented by various Oil Companies across the globe. Our recommendations shall be supported by actual data we have gathered from the 8,000+ fugitive emission projects we have done in the past. Also in this paper, we would like to highlight the importance of an integrated methane emission management platform (software) to ensure a transparent, auditable and manageable Methane Emission program.