Enhanced Oil Recovery

From Great Lakes Wiki

Michigan is the only state east of the Mississippi River that injects carbon dioxide (CO2) underground to force out crude oil.

Within Michigan, there is only one company that does it and on September 20 they produced their one-millionth barrel of oil.

Traverse City-based oil and natural gas producer Core Energy leads the state in “enhanced oil recovery,” a process tied to carbon capture and sequestration because it injects CO2 underground to force oil to the surface.

“The real story in Michigan is all of the oil being extracted, especially by EOR (enhanced oil recovery),” said Robert Mannes, president of Core Energy. “And you can help the economy by extracting local oil.”

Core Energy manages five enhanced oil recovery projects on 80 acres in Otsego County, near Gaylord. On December 2, it received permission from the Michigan to start drilling a sixth, known as the Chester 2 project.

Drilling will start in February 2009, Mannes said.

Enhanced oil recovery is aptly named because it follows standard, traditional ways of drilling for oil. Traditional drilling is used at first, then enhanced recovery replaces it to keep the oil coming.

Extracting oil works like fizz coming from a shaken soda after the cap is removed. A great deal of oil surfaces at once and then settles. This is when traditional oil drilling gets less and less effective, eventually only taking about 10 percent of all the oil in the reservoir, according to the U.S. Department of Energy.

When the oil “settles,” a company like Core injects the carbon dioxide to force out an additional 30 to 35 percent more oil.

Core sits on about 21.5 million barrels of oil, of which only about 35 percent will see the light of day. The company estimates that it stands to extract about six to 13 million barrels before all possible oil is recovered and the wells are plugged.

Not only does enhanced oil recovery open the door for domestic oil options, it also has a 70 percent less carbon footprint than conventional oil extraction, according to Mannes.

Core has built infrastructure in Otsego County to pipe CO2 emissions from a local gas processing plant to their oil wells about nine miles away. That CO2 would have otherwise been emitted into the atmosphere and contributed to global warming.

The pipeline that takes CO2 from a gas processing plant nine miles away to Core's oil wells for injection.

At the surface, the CO2/oil mixture is separated, where the oil is sold and the CO2 is recycled back into the ground.

Core Energy owns the property in Gaylord where the Department of Energy piloted a carbon capture project of injecting 10,000 tons of CO2 into a barren saline aquifer in February. However, that project only tested the ability of underground storage of CO2 and didn’t produce any new oil.

“Carbon capture is one thing,” said Rick Henderson, supervisor for the Michigan Department of Environmental Quality’s Office of Geological Survey. “But enhanced recovery recycles it [CO2] while also producing oil.”

“I obviously favor it [enhanced oil recovery]. We’re keeping CO2 out of the air and using it for a net gain. It’s a win-win situation,” he said.

At the Chester 2 site, Core vice president of engineering and operations Rick Pardini said about 104,650 tons of CO2 will be injected over a 12- to 18-month period to pressurize the well. This may change based on how well the CO2 mixes with the oil to bring it up, as well as how much CO2 is lost in the process, which isn’t much, he said.

“Some months it could be more, some months much less,” he said.

Pardini compares an oil well right before enhanced oil recovery to a flat bike tire. The CO2 acts like an air pump to pressurize the well. At the point where the CO2 and oil is separated and a small amount of CO2 is lost, it’s like a small hole in the tire where air slowly escapes.

“Imagine a person using an air pump to get the tire inflated,” he said. “That’s what we do by pumping in more CO2.”

In the Midwest , Michigan has the most concentrated oil and gas fields underground. The Department of Energy estimates that Michigan has about 500 million barrels of recoverable oil via enhanced oil recovery. Across the U.S., the number is 89 billion barrels.

Oil was first drilled near Core’s Otsego County location in January 1973. The first small-scale enhanced recovery project was launched in 1997. To date, Core has been the only company to use the method.

Merit Energy in Kalkaska is working to acquire permits for enhanced oil recovery using only CO2. Oil recovery using water has also been proven, but is far less economical and much more of a waste than using strictly CO2.

Michigan granted Core permission to use water only as a backup plan if the CO2 is not working.

“We don’t plan on using it (water),” Mannes said in testimony to the state’s Office of Geological Survey. “But just in case, we’d like to have the option.”

Enhanced oil recovery via CO2 is still too young to be considered a major component of a domestic energy policy but should start influencing policymakers, according to Mannes.

“CO2 (enhanced oil recovery) is a wonderful bridge to the future,” he said. “A lack of domestic energy policy threatens us more than our oil needs.”

Amidst the political and social shift toward alternative fuels and energies, Mannes is convinced his work in the oil and gas business is as important as ever.

“I don’t personally worry about job security,” he said.

“We’re always going to need oil. We will never wean ourselves completely.”