Efficient methane emissions management of critical resources, such as natural gas in domestic pipelines, not only makes economic sense, but it is also increasingly necessary for our planet and people.

Regulations, international guidelines and industry performance indicators define frameworks to minimise methane emissions. Technologies and operational knowledge are more needed than ever.

Natural gas pipelines remain a potentially significant source of gas emissions through bulk venting or flaring, particularly prior to pipeline maintenance or modifications, where gas is removed from the targeted pipeline section rapidly, safely and with as little as possible environmental impact. After maintenance has been completed, the gas-up phase can also be a source of undesirable emissions.

This paper focuses on current and future techniques, technologies and practices that allow these emissions to be reduced, and match or improve on industry targets. Today, there are only a limited number of technologies and operations allowing bulk transfer of natural gas:

• Displacement by nitrogen purge
• Recompression by a mobile, temporary compressor system
• Combination of both

Traditionally, focus was given to very large amounts of gas to be transferred: it is now essential to have solutions for small volumes, thanks to evolving technologies becoming more agile, with high emission reduction efficiency and improved financial returns.

Additionally, it is not only about performing the operations but also the quality of data measuring the net impact – in CO2e – of gas transfer operations and allowing a comparison of the available technologies that includes environmental criteria.

The scope of this paper is both to describe different ways to deliver pipeline gas evacuation operations, for various types of gas volumes with the highest operational and environmental efficiencies and to present net carbon footprint data in a simple and auditable way, which could contribute to the best operational and technology choices.