ExxonMobil is counting on its long track record in carbon capture for use in enhanced oil recovery to underpin its ambitions for permanent geologic sequestration of greenhouse gases.
Carbon capture and storage (CCS) has long been known as a tool to boost the efficiency of oil production. But with Paris Agreement targets becoming more important, ExxonMobil and others say their technology offers a range of opportunities, from transport to carbon capture and subsurface disciplines, including permanent storage projects.
While there are some who think that carbon capture is new, Matt Crocker, senior vice president of strategy and business development at ExxonMobil Low Carbon Solutions, told Upstream: “It’s a well-proven technology that we’ve been doing for many years. We actually account for 40% globally of man-made carbon dioxide that’s being captured.
“That’s given us a lot of experience to draw on, and as we’re talking to the various parties and stakeholders that experience is something that is well recognised,” he said.
ExxonMobil has announced permanent sequestration projects at its Baytown refinery in Texas and with CF Industries in Louisiana in the US.
The company is already pursuing permanent carbon storage at its LaBarge, Wyoming, facility that has been capturing and storing CO2 for years.
LaBarge, labelled as home to one of the world’s largest carbon capture plants, took the final investment decision earlier this year and the site was increased in size from 6 million tonnes per annum to 7 million tpa.
“EOR has played an important role historically, and I think it will continue to play a role in the deployment of CCS, but the interest has moved towards dedicated geologic storage in the Class VI regime,” Jeff Erikson, general manager of client engagement at the Global CCS Institute, told Upstream.
According to the Global CCS Institute database, about 220 commercial-scale CCS facilities are in the planning stage around the world. Of those, about 15 specifically intend to use the CO2 for EOR while the rest are described as decarbonisation-driven.
This differs from the current state of CCS, which shows 22 out of the 32 large-scale CCS facilities in the world use their CO2 for EOR, Erikson said.
“When EOR was first deployed in the US, it wasn’t seen as a climate mitigation tool. It was seen as a way to improve the recovery of oil. Then slowly there was a recognition that there’s CO2 reduction advantage as well,” he said. “Now it’s very much seen as the climate mitigation tool.”
Class VI Wells
In the US, CO2 injection for EOR uses Class II wells which are essentially geared to oil production whereas permanent carbon sequestration, as a category of activity, uses Class VI wells.
Class VI wells are specified for permanent carbon sequestration not related to oil and gas production.
Most CCS projects will be required to acquire permits for these newer wells and the permitting process may turn out to be more complicated as operators have to report directly to the Environmental Protection Agency (EPA).
At least 40 states have been granted primacy, or regulatory authority, over Class II wells, so the EPA is no longer a part of the permitting process for Class II wells in those states. Only two states, North Dakota and Wyoming, have primacy over Class VI wells, which means that for now all other projects will have to go through the EPA for permitting.
Applications ramp up
“This programme has really just ramped up in the last year. I mean, you went from there being zero applications pending a year ago and now you see the volume cutting across the various regions. These are reviewed at the regional level,” Brittany Bolen, senior policy adviser at law firm Sidley Austin, told Upstream.
Bolen was previously the head of the EPA’s Office of Policy.