Heavy oil contains not only carbon—it’s also an extremely rich source of hydrogen. Hydrogen is an emissions-free form of energy that can be used to fuel vehicles or power electricity. Until now, extracting hydrogen from hydrocarbons was not considered economic. But researchers at the University of Calgary’s Global Research Initiative (GRI) in Sustainable Low Carbon Unconventional Resources have developed a technique that could unlock this clean energy source from the oil sands.
“If you can get hydrogen from both hydrocarbons and water, you have a massive hydrogen storage system underground—one that provides another potential energy future for oil reservoirs,” says Ian Gates, the GRI’s director and a professor at the Schulich School of Engineering.
Six years ago, Gates and research associate Jackie Wang discovered that heavy oil reservoirs, under certain conditions, could generate large amounts of hydrogen. As they experimented in the laboratory, they focused on a process called in situ combustion.
Under this process, oxygen-rich air is injected into the underground reservoir. This causes the bitumen or heavy oil to combine with oxygen, a chemical reaction (called oxidation) that generates heat. The resulting in-reservoir high temperatures set off another series of reactions which, among other things, turns hydrocarbon molecules into carbon oxides that are left in the reservoir, and hydrogen gas that can be collected at the wellhead.
To advance their approach, the University of Calgary researchers approached Proton Technologies in 2016. Proton is a Calgary-based cleantech start-up. Together, they’ve designed and fabricated a specialized membrane, called a hygenerator, to filter pure hydrogen from the gas stream at the surface. To evaluate their technology, they ran simulations mimicking conditions found in the field. The results showed the membrane could function under high temperatures and pressures to remove pure hydrogen while leaving carbon in the apparatus.
In early 2018, the researchers helped Proton conduct a pilot at a demonstration facility owned by the company near Kerrobert, Saskatchewan.
“Everything we learned from our lab tests was proven. The pilot was able to produce a beautiful blue hydrogen flame,” Wang says.
Building on this success, Proton is now planning a larger demonstration project for the site in 2021. The new production well will be drilled in October 2020. If this is successful, the technology could be commercially applied to extract hydrogen from heavy oil and oil sands reservoirs, as well as even declining oilfields, where large quantities of hydrocarbons that are otherwise uneconomical to recover, remain. In each case, a production well would collect the hydrogen and direct it to surface for removal and storage.
Gates and Wang are hopeful the technology could provide an important new opportunity for industry.
“This could open another door. If this technology is realized commercially, Alberta and Western Canada could produce a lot of clean hydrogen energy. This process could turn even low-grade reservoirs to tremendous value,” Wang says.