By: Katherine Lymn, Forum News Service DICKINSON, N.D. -- Carbon dioxide flooding, a tertiary method for recovering oil, is coming to North Dakota for the first time ever by way of Bowman County.
Denbury Resources, a Texas-based company whose primary focus is CO2 flooding, acquired the 177-square-mile Cedar Hills field last year that is a prime candidate for the method, said Lynn Helms, director of the state Department of Mineral Resources.
The company already has a CO2 flood in Montana, which is getting its CO2 from a ConocoPhillips natural gas plant in Wyoming. It plans to build another pipeline to get the CO2 to North Dakota for the newly acquired land around 2020, Denbury spokesman Ernesto Alegria said.
CO2 flooding is one of the more common types of “enhanced oil recovery.” Other recovery methods include injecting everything from microbes to steam or air into reservoirs to help coax out the oil.
When the CO2 comes into contact with crude at reservoir conditions, Helms said, it causes the oil to increase in size and decrease in viscosity, “or make it more runny,” so it’s easier for the oil to move through the rock.
Mature oil fields, where traditional oil drilling has run its course, can produce more oil with flooding.
“Eventually the fluids in the formation lose their pressure and so you’re at the end of the rope unless you do something differently,” said Steve Melzer, a CO2 flooding consultant based in Midland, Texas.
“Just how you get dirt off your hands, you can do the same thing to get oil off the formation,” he said.
“CO2 does that just like a good detergent would.”
The method increased in popularity in the late ’90s when companies like Denbury started specializing in the technology, Helms said.Now, there are about 140 projects around the world using the method.
Denbury’s CO2 flooding at Bell Creek in Montana is going as planned, and as for expansion, the next steps largely center on laying pipe, Alegria said.
The company, which has a large presence in the Gulf Coast, is looking north for the future, he said.
“As we develop our Gulf Coast properties, obviously (oil is) a depleting resource,” Alegria said, “so really to set the company up in future growth the north region is definitely gonna be that driver for us.”
Alegria wouldn’t comment on the company’s projections for North Dakota oil recovery, but Helms said Denbury is hoping to get 50 to 60 percent of the oil remaining in the reservoir, or 150 to 200 million barrels.
For Bowman County, it’d mean 400 or 500 more wells, and twice as many oil-related jobs as there are now, Helms said. Drilling could take five years and the flood could last a total of 35 years.
On-the-ground action in North Dakota is years off. But Alegria said Denbury’s expansion to other CO2 flooding-viable fields, which Helms said include much of the Tyler formation, is also possible.
“Everybody is really excited about possibly applying (CO2 flooding) to the Bakken and Three Forks (formations) sometime in the future,” Helms said. “But they’re just doing lab testing now.”
Helms said the DMR has heard an inquiry from another Bowman County operator about the tax incentives that come with CO2 flooding, hinting at other interest in the method.
Whiting Petroleum does flooding in Texas’ famous Permian Basin and could “very easily” do it in North Dakota as well, Melzer said.
Operators using the CO2 flooding pay no oil extraction tax, he said, which is to encourage tertiary recovery.
“(CO2 flooding) does a number of things,” he said. It increases jobs and production, but more notable and specific to this method, it reuses CO2 that is emitted as a byproduct of other operations.
Melzer said the environmental movement focused on cleaning the atmosphere could lead to a push for more CO2 flooding as a way to reduce emissions, because it’s a use for CO2 that’s captured instead of emitted.