Containing the Smallest Element: Adapting Carbon Expertise Critical to Solving Hydrogen-Related Challenges

The smallest element in the world brings with it big potential and hopes. The easily escapable element is being eyed as one of the big answers to arguably the largest question of our time. How does one decarbonize without destabilizing?

By Matt Nemeth, Communications Lead – Stream-Flo Group of Companies

As the world grows, with that growth fueling an ever-increasing demand for energy, and more energy being consumed across the globe every day, the reality of a decarbonization equation that addresses the climate change questions adequately – without throwing the global economy into a tailspin, curtailing developing nations’ progress, driving inflation to higher levels, and most importantly, jeopardizing energy security on a massive scale – becomes more elusive.

Perhaps it is fitting that many are looking to the elusive, yet extremely abundant, element of hydrogen as the answer. Hydrogen, the most abundant element in the Universe, is highly combustible. When it burns, its only byproduct produced is water.

It almost sounds too good to be true. Why is not everyone driving around in vehicles powered by hydrogen fuel cells? Two reasons: cost and danger. Current catalysts for hydrogen fuel cells, platinum chief among them, are too ex-pensive to be commercially viable. Also, as learned from the Hindenburg disaster, uncontained hydrogen can have catastrophic consequences.

The nascent hydrogen-as-energy industry is making progress, especially when it comes to the production and storage side of things, two aspects that will aid greatly in driving down the very high costs the two previously mentioned challenges pose.

For example, Stream-Flo has been helping to equip those undertaking both endeavors. The company has provided hydrogen wellheads and accoutrements for a pro-duction well in Mali and a storage well in Alberta. Given hydrogen’s small size, containment was the first challenge to tackle.

Drawing heavily from experience satisfying critical sour requirements with H2S, and fugitive emissions standards through helium testing, their containment plan centered strongly around seal redundancy. Given helium and hydrogen being of similar molecule size, the past success seen containing the former showed the same approach works for the latter.

Then it became a material problem. The expertise in the oil and gas industry by the company came in handy, as Project Engineering Manager Rick Miko, the in-dividual who led all the production and storage well design efforts, details:

“We found that materials that are suited for H2S environments work very well in hydrogen storage environments,” said Miko. “There is the same design concerns with pure hydrogen as there would be for H2S, namely embrittlement. Molecular hydrogen (H2) dissociates into hydrogen ions (H+) which then dissolve into the alloy, coalescing at flaws or grain boundaries. When the H+ ions recombine into H2, they take up a much larger area than they did as individual ions, so the formation of the H2 molecule places stress on the metal lattice. If the microstructure is not sufficiently ductile to absorb these introduced stresses, it will become brittle or crack. Using NACE compliant materials that have demonstrated sufficient ductility for the H2S service gives us assurance that the material will be suitable in H2 service.”

With the wellhead work taken care of, it was time to turn sights on designing the hydrogen gate valves. These are the valves that come off the wellhead and run fully open or closed to either provide full flow of a liquid or gas in a pipeline, or completely shut it off. Design took some additional consideration, due to the fact that the valve carries a bit more risk as the bonnet seal and stem seal are essentially exposed to hydrogen. Whereas with a wellhead, there are three seals before a leak to atmosphere could occur.

Approaching the task from that angle, it was decided that a redundant seal above the stem packing and a welded hardface on the gate and seats would be best in a hydrogen-related valve to limit porosity. As Miko earlier stated, porosity can lead to embrittlement which can subsequently lead to a loss of containment.

With critical sour, high pressure, and materials expertise forming the design stage, it was time for the company’s hydrogen team to perform prototype testing. The testing was carried out in the company’s manufacturing facility in Edmonton, Alberta.

When all was said and done, the well-head passed with zero issues. This included the equipment being subjected to two additional leak detection methods in addition to the standard method; one being a hydrogen sniffer, and the other an infrared camera. With the gate valve, given its higher risk, a battery of tests were called for.

“We went over and above what we did for our wellheads for our valves,” continued Miko. “We did the pure hydrogen testing, and then a full PR2 Annex-F API 6A test, followed by a fire test. We did that for our suite of hydrogen valves, ranging from two inches to nine inches.”

Testing done, it was time to send the finished products to the site where the real would render its verdict. The hydrogen storage well required solution mining to make the salt cavern where it would be stored. A full 24 months of continuous pumping of water into the salt formation to produce saltwater – and then reusing that saltwater to mine the cavern – was required.

“Imagine saltwater and pressure and flow, with high volumes of flow – it is a very erosive and corrosive environment,” said Miko. “We had to use materials and components that could both be used in a hydrogen environment and a saltwater environment.”

Doing so required being in lockstep with the different phases of the solution mining and storage well project, providing compatible equipment that could easily be swapped out given the current stage. With the cavern created and two rounds of storage testing completed, Miko says the hydrogen equipment performed as expected. “It was a really smooth project start to finish,” he said.

“The oil and gas industry is going to be well equipped to handle this as a challenge. I think as an industry we are ready to start working on hydrogen projects,” summarized Keith Farquharson, Stream-Flo’s Senior Advisor, who has been studying the hydrogen-as-resource question for many years. Where the market stands now, Farquharson is quick to temper expectations around it quickly rushing in to save the day and answer all the big questions outlined at the beginning.

“There is no big supply of hydrogen. There are great dreams and aspirations, but the hydrogen industry is small,” stat-ed Farquharson. “There are six hydro-gen storage wells in existence right now that are functioning as storage wells.”

Still Farquharson says there will definitely be a future opportunity around the element, and it will take those currently tackling the big challenges in energy to be at the forefront of whatever comes next. “There is a carbon problem, and the experts on carbon are in the oil and gas industry right now. That is who is going to solve this thing.”