What You Need To Know
Valve Innovation is Key: Companies are developing stemless and zero-emission valves that eliminate the main sources of methane leaks.
Electric Actuators Outperform Pneumatic: Switching from methane-powered pneumatic actuators to electric alternatives can reduce energy use by 65% while eliminating emissions.
Measurement Standards Are Lacking: The industry struggles with inconsistent methane detection and quantification methods, with recent research showing Canadian emissions may be seven times higher than officially reported, highlighting the need for standardized measurement practices.
According to the U.S. Environmental Protection Agency (EPA), methane accounts for 12% of all U.S. greenhouse gas emissions. Breaking it down, the natural gas and petroleum sector is the most significant contributor with 28%. Enteric fermentation is second with 25%, while landfills account for 16%.
To counter this, in 2024, the EPA and the Department of Energy (DOE) announced an $850 million package for projects designed to reduce methane pollution from the oil and gas sector.
While the future of this funding, which comes via the Inflation Reduction Act, is in doubt — and neither EPA nor DOE was able to offer any clarification as to its current status — the need to tackle fugitive methane emissions is still driving advances in technology.
Revamping Valves — a Stemless Approach
Knowing that valves contribute to fugitive emissions, mostly from the stem and stem packing, Oxford Flow, Oxford, UK, decided to focus on innovations here.
The result is the ES family of stemless axial flow valves. No stem, no stem packing, inherently no emissions. And because they do not have a mechanical drive train, the ES valves are not subject to stresses and side loading that cause poor performance and premature mechanical failure.
According to the company, the ES can be operated by a compact electrohydraulic powerpack with its pressure-balanced trim, significantly reducing the valve package's size and weight by 50%.
The valve internals are also designed to provide very high flow rates while minimizing turbulence. This reduces erosion on sealing surfaces and allows the ES to provide long-term zero leakage in a variety of severe applications.
In February, the company’s Houston operation secured an order worth nearly $1 million from BP in the U.S. for ES stemless axial flow valves. It’s the largest order to date for the valves and a significant milestone in the company’s drive to become a leading supplier in the U.S. market.
Last December, Oxford Flow won $25 million in funding from BP Ventures and Energy Impact Partners (EIP), New York, to scale up its operations. EIP is an investment platform that helps entrepreneurs model and scale their technologies and businesses.
“Oxford Flow’s technology could be important for BP’s core operations, helping reduce maintenance and downtime costs at our production facilities, as well as being utilized for other emerging businesses such as hydrogen,” said Gareth Burns, vice president of BP Ventures.
Steven Yang, principal at EIP, added, “Methane emission reduction is one of the most cost-effective strategies for global greenhouse gas abatement. We believe Oxford Flow’s innovative valves and regulators are strategically important for upstream, midstream and gas utility operators focused on minimizing fugitive emissions and lowering operating costs. We also see Oxford Flow playing an important role in enabling infrastructure for use-cases such as hydrogen, ammonia and captured carbon dioxide.”
Eliminating Valve Leak Paths
Mokveld, Gouda, The Netherlands, tackles the issue with its new Zero emission control valve, which is designed to eliminate fugitive emissions over the valve's lifetime.
According to the company, the new valve builds on the existing axial flow control valve, but the internal actuator removes the need for dynamic packing seals, thus eliminating the main leak path of more common valve designs.
Only static seals to the atmosphere are present, and the process fluid is not in direct contact with them. Without shaft seals and body joints, unintentional leaks are impossible at any time during the lifecycle.
The company also says its new valve requires reduced leak detection and repair efforts. In fact, the maintenance-free concept makes it possible to weld the valve in the line and even install it in buried applications. The electric servo actuator provides continuous diagnostic data to aid with predictive maintenance.
The Zero emission valve achieved its TRL7 (technology readiness level) designation after 18 months of trouble-free operation at Dutch natural gas infrastructure and transportation company Gasunie’s Beverwijk facility.
Here, the quality band is quite narrow, and the mixing station at Beverwijk is considered a demanding application. Accurate control and immediate response to changes are required to avoid a shutdown resulting in out-of-spec gas.
Normally, control is performed by an eight-inch valve for high flows and a four-inch valve for low flows. An eight-inch Zero-emission valve was installed and successfully performed both tasks, with no need for a changeover to smaller lines as demand fluctuated.
An added benefit was the reduction in the number of hazardous areas at the plant.
Gasunie now has plans to take advantage of the valve’s maintenance-free design to use it in underground applications.
In a separate development, Gasunie last November entered into a long-term agreement with Mokveld to supply control valves for use with a proposed national hydrogen transport network.
Gasunie subsidiary Hynetwork is managing the project, which will repurpose some existing pipelines to carry hydrogen and install new ones where the existing network is not suitable.
The network will connect five industrial clusters to each other, to other countries and to hydrogen storage and import locations.
Control Valves
For its part, Rotork, Bath, UK, is developing an electric control valve actuator portfolio.
Control valves used in upstream processing are usually activated by pneumatic diaphragm actuators, which use process gas for power and release methane every time the valve is stroked. Some operators have tackled these emissions by replacing process gas with compressed air by deploying air compressor units at production sites.
Rotork says that its technologies not only help achieve net zero emissions with a solar-powered 24 VDC supply option but also help reduce the overall life cycle costs compared to the instrument air actuator alternative.
Electric actuators only consume power when in operation, unlike pneumatic actuators and controls, which need a constant supply of either gas or locally produced compressed air.
In May, the company supplied over 200 actuators for use on an upstream gas processing platform being constructed by exploration and production company ONE-Dyas, Amsterdam. The actuators will support the platform's electrification and automation, which will process wet natural gas into dry gas for pipeline export.
ONE-Dyas says the platform will be the first fully electrified gas production platform in the North Sea. When it starts operations at the end of 2025, it is expected to reach near-zero operational emissions under Scope 1 and 2, supplied by the nearby German Riffgat offshore wind farm.
Pneumatic Actuator as a Standalone System?
Another company focused on mitigating methane emissions from gas-powered pneumatic devices is Hybrid Automation, Derry, New Hampshire.
Taking a different approach, the company doesn’t manufacture pneumatic actuators or valves. Rather, it has developed a patented interface that allows pneumatic actuators to function as a standalone system, like an electric actuator. So, there’s no need to connect to a huge compressor feeding air to hundreds of pneumatics via tubing.
Air lines from the hybrid automation controller connect directly to the intake and exhaust ports of the existing pneumatic actuator, eliminating the need for methane. It works regardless of pneumatic manufacturer or actuator type.
Once its system is charged with air or an inert gas, it converts a pneumatic actuator into a closed-loop, zero-vent-to-atmospheric platform.
According to company founder and managing director Bob Connal, it has the reliability of a pneumatic actuator with the flexibility of an electric actuator.
So, as well as converting existing methane-powered pneumatic actuators to a zero-vent-to-atmosphere system, the technology can successfully compete within the electric failsafe sector as it requires no connection to a remote compressor station.
According to the company, tests using an industry standard (open loop) pneumatic system versus a hybrid automation (closed loop) system reduced energy use by approximately 65% — a figure the company says applies to all actuator sizes.
Identifying What’s Best for Your Process
However, no one technology fits all when it comes to methane emissions, a fact that prompted SLB (formerly Schlumberger), Houston, to launch its end-to-end emissions solutions (SEES) business in 2022.
SEES was set up specifically to help operating companies find the best technologies and partners from a patchwork of disparate offerings.
Schlumberger screens a wide array of measurement and abatement solutions to identify the most cost-effective technology mix for any operator’s specific assets. This, the company says, gives access to a full range of curated, best-in-class third-party and in-house solutions that have been rigorously evaluated.
“Though other service providers can inform an operator where emissions are occurring, Schlumberger — through its end-to-end offering — finds the emissions and then takes remedial action to eliminate them. In addition, robust data and a digital foundation will enable customers to have a secure, reliable single place for integrating multi-source emissions data with advice, plans and insights,” according to a news release.
Since its launch, the business has completed more than 20 projects worldwide, providing commercial technology solutions and consultative services for continuous methane monitoring and gas-to-value services, which focus on monetizing the value of captured methane gas. It is also working on a global methane measurement and reporting project for Eni, although a spokesman was not able to give an update on how this is progressing.
Meanwhile, in January this year, the company launched OptiSite, an AI solution for entire end-to end production networks.
Like SEES, OptiSite is designed to deal with a highly fragmented production landscape with multiple equipment types and manufacturers and allow users to visualize their data in real time from equipment and assets across an entire network (Figure 1).
Guide to Methane Detection and Quantification Technologies
In April, four industry groups, including the Oil and Gas Climate Initiative (OGCI), London, published an 82-page guide to help oil and gas operators select and deploy methane detection and quantification technologies.
It updates the original guide, which was published in 2023, to include advances in methane detection technologies and relevant data sheets and decision trees that operators would use to deploy these technologies. This includes six new technologies and updates to 14 others.
Interestingly, one of the main challenges identified by the report is a lack of independent standards for comparing technologies.
“Different technologies sense methane differently, quantify methane in different ways, attribute emissions to specific sources using different formats, and report methane emissions detection and quantification differently,” it noted.
The report recommends that the industry develop consistent practices that allow robust and comparable testing of different methane emissions detection and quantification technologies. This could include, for example, a unified definition of detection threshold and probability of detection using comparable metrics.
It’s a view bolstered by a June 10 article published in Environmental Science & Technology by researchers from McGill University, Quebec, Canada.
They found that methane emissions from Canada’s dormant oil and gas wells are seven times higher than previously thought.
The Department of Civil Engineering team directly measured methane emissions from 494 wells across five provinces. The national emissions estimate they arrived at — 230,000 t/yr — is sevenfold higher than the 34,000 t/yr reported in Canada’s National Inventory Report.
“One surprising finding was just how much the drivers of emissions varied between provinces. We thought geological differences within provinces would matter more, but the dominant factors appear to be at the provincial scale, likely due to variations in policy and operational practices,” said Mary Kang, associate professor of civil engineering at McGill and senior author on the paper.
The researchers emphasize that improving methane data is critical to meeting Canada’s climate targets.
“If we don’t have accurate estimates of methane emissions, we can’t design effective climate policies,” Kang concluded.
About the Author
Seán Ottewell
Editor-at-Large
Seán Crevan Ottewell is Chemical Processing's Editor-at-Large. Seán earned his bachelor's of science degree in biochemistry at the University of Warwick and his master's in radiation biochemistry at the University of London. He served as Science Officer with the UK Department of Environment’s Chernobyl Monitoring Unit’s Food Science Radiation Unit, London. His editorial background includes assistant editor, news editor and then editor of The Chemical Engineer, the Institution of Chemical Engineers’ twice monthly technical journal. Prior to joining Chemical Processing in 2012 he was editor of European Chemical Engineer, European Process Engineer, International Power Engineer, and European Laboratory Scientist, with Setform Limited, London.
He is based in East Mayo, Republic of Ireland, where he and his wife Suzi (a maths, biology and chemistry teacher) host guests from all over the world at their holiday cottage in East Mayo.