Identifying Natural Gas Leaks to the Atmosphere with Optical Imaging

Methane is one of the most significant anthropogenic greenhouse gases, whose global warming potential and sources are well documented. The natural gas industry is a major source of methane emissions. In 2001, unintended (fugitive) leaks from valves, piping connectors, open-ended lines, and pump and compressor seals totaled 3.9 Tg (58% of total U.S. emissions from the natural gas industry). In the U.S. hydrocarbon industry, less than 1 percent (%) of the thousands of potentially leaking sources contribute over 90% of fugitive emissions. Finding these few large leakers in a cost-effective way is a challenge for the industry. The current practice in the U.S. and other countries is to visit each and every potentially leaking component, and “sniff” it with a hand-held gas detector. This is time consuming, labor intensive, costly and limited to components within the reach of the gas detector user. Optical imaging (OI) is a new technology that allows the user to “see” a live image of fugitive gas leaks into the atmosphere. Several different types of OI technologies -sensitive to fugitive leaks are being developed, and one is now commercially available. These devices allow a user to scan hundreds of components in minutes, identify those few that are leaking, and video record the leakers for verification and documentation. This paper describes different OI leak detection technologies, how they are more cost effective than currently used hand-held gas detectors, what may be possible in methane emission reductions, and future outlook for OI. The presentation will show an actual video of gas leaks detected with an optical imager.