Compressed Air Pneumatics for Methane Mitigation

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Objectives/Scope With the challenge of reaching carbon neutrality, the energy industry will need to be transformed. One of the key challenges facing the industry is eliminating Scope 1 emissions from the pneumatic devices used in wellpad automation and control. This practice accounts for roughly 45 million tons of CO2E/yr in the United States alone. Eliminating these emissions from existing brown-field sites is a significant challenge given that many of these well pads are in remote locations and suffer from a lack of reliable and sustainable electric power. Methods, Procedures, Process Compressed Air Pneumatics (CAP) is an innovative technology that replaces the methane emissions of pneumatic devices with clean, dry, compressed air. By employing highly reliable free-piston Stirling engine technology the end-user utilizes a small fraction of the normally vented methane to efficiently generate continuous and reliable electric power and clean, dry, compressed instrument air. CAP systems conserve valuable instrument gas and entirely eliminate methane venting at the well pad. They also eliminate the "wet-gas" issues associated with low-bleed pneumatic device contamination. In addition to compressed air for well pad automation, CAP technology is able to further provide additional utility grade electric power for additional well pad loads. Operators are able to further reduce their carbon footprint by harnessing the reject heat of the Stirling engine to keep process lines warm, further displacing the emissions of low-efficiency gas fired heaters. Another advantage that Stirling engine based CAP solutions gives upstream producers is the option to commission their instrument air system on tanked fuels like propane and readily switch over to instrument gas once wells are operational. Results, Observations, Conclusions A deployed CAP system on a multi-well pad in the Barnett Shale formation in Texas mitigated the vented emissions of 42,000 SCF of Methane in a 30-day period, which is equivalent to the removal of over 1,000 tCO2E on an annual basis, equivalent to removing 200 cars of the road. This same wellpad had zero downtime due to lack of pneumatic control or vent contamination across the same period. In addition to pneumatic control the CAP technology provided the wellpad prime power electricity, eliminating the need for large solar panels and cycling battery banks. Novel/Additive Information This technology when rightsized can maximize system value, driving down the cost of methane abatement below $2/tCO2e