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CO2 demonstration project proposed at Milne Point First of its kind would reduce emissions while increasing heavy oil recovery; also would it adds value to the gasline options Patricia Jones PNA Contributing Writer
The ever-increasing amount of carbon dioxide emissions and how best to mitigate those pollutants is an energy issue receiving global attention, as well as research efforts and governmental spending.
Most proposed solutions to the greenhouse gas issue involve either reductions in use of fossil fuels, development of new technologies that reduce the amount of carbon dioxide — CO2 — produced by burning conventional fuels or coming up with new ways to capture and store the emissions.
But Iain Wright of BP Exploration (Alaska) Inc. sees opportunity in those unwanted gaseous pollutants. As BP’s CO2 team leader for Alaska Gas, Wright has put together a project proposal that would take carbon dioxide emissions from a North Slope power plant and use them productively in enhanced oil recovery projects for viscous oil deposits.
“Alaska is a unique place for CO2 storage and capture,” Wright said. “A lot of places will be watching because they could benefit from development with CO2.”
Wright outlined his project and its role in the global effort to reduce carbon dioxide emissions during an energy workshop held at the University of Alaska Fairbanks.
In a nutshell, Wright’s project would capture carbon dioxide produced by two gas turbines at Milne Point, 550 tons per day or about 200,000 tons per year of CO2.
Those emissions would be injected underground into a heavy oil formation, where CO2 would reduce viscosity in oil. In addition, CO2 swells when underground, so it would push heavy oil out of its geologic formations, significantly increasing recovery from existing oil production facilities.
“This would be the first CO2 captured from gas turbine exhaust,” Wright said. “It’s a much more technically challenging thing to do, that’s why it hasn’t been done before.”
Other projects that have used CO2 in enhanced oil recovery typically take naturally occurring carbon dioxide and inject it. “They’re not contributing to the climate change aspects,” he said, referring to the environmental benefits of reducing emissions by storing CO2 underground. Milne CO2 project currently uneconomic So far, BP has invested about $500,000 on preliminary engineering for the demonstration project, which would be the first of its kind, Wright said.
While there currently is no projected cost for such a facility, it would likely be in the “tens of millions of dollars,” Wright said. “When you’re looking at a new kind of industry or technology, the first prototype is always more expensive.”
In addition to the newness aspect, such a CO2 project tends to be expensive due to the high-pressure characteristics of the gaseous material, Wright said.
“The trouble with CO2 is that its ability to expand and swell underground is bad on the surface,” he said. “You have higher costs in the materials necessary to handle it on the surface.”
Wright hopes to attract additional interest and funding from governmental research entities.
“Right now the project is not economic … BP is not interested in a project that will lose a significant amount of money,” Wright said. “So I’m looking for funding help.” Global interest, research on CO2 emissions A number of industry and government representatives making presentations at the UAF energy workshop talked about the projected increase in global carbon dioxide emissions.
“The world population right now is about 6 billion, and the U.N. is projecting it to grow to 10 billion by the end of the century … there is a 32 percent increase in total energy demand projected from 2000 to 2020, and in the U.S., the use of fossil fuels will increase from 85 to 90 percent (of the national energy usage),” said John Winslow, representing the National Energy Technology Lab at the conference.
“The technology gap exists between where present technology will take us and where we need to stabilize that CO2,” he added. “This administration is very committed to addressing the greenhouse gas issue, and (President Bush) is putting money where his words are.”
Funding for CO2 sequestration research efforts nearly doubled in 2002 from previous levels, Winslow said, to $32 million. That research funding will increase again in 2003, to $54 million. “Our planning for 2004 is significantly higher than $54 million.”
Those research dollars cover a variety of projects — looking at ways to reduce emissions, as well as methods to store carbon dioxide underground, Winslow said.
“In direct CO2 sequestration methods, CO2 is collected inside a power plant or other large source and pumped underground for long term disposal,” he said. “CO2 can be used to sweep gas from unmineable coal seams … theoretically it can be disposed in the deep ocean, or it could be pumped into depleted oil and gas wells.”
Researchers are also investigating auxiliary benefits from storing CO2 underground, such as production of unconventional supplies of gas. (See story on gas hydrates.) Gasline could benefit from CO2 underground storage In addition to reducing existing carbon dioxide levels on the North Slope, currently estimated to be 15 million tons per year, Wright said, his project has far-reaching applications.
Commercial development of the proposed natural gas pipeline project would create a need for a carbon dioxide disposal system on the North Slope.
Currently, about 8 billion cubic feet of gas is gathered from oil production wells, and reinjected into the underground reservoirs. Carbon dioxide makes up about 12 percent of the existing North Slope gas supply, Wright said.
The proposed commercial natural gas project anticipates using a little more than half of that daily gas flow for transportation to market via a gas pipeline.
“You’ve got to take out that CO2, because you don’t want to ship it all the way down the pipeline,” Wright said. “If you’ve got CO2 captured and you can do something useful with it in Alaska ... it adds value to the pipeline options.” Link with gas hydrate development Finally, Wright’s CO2 team is involved with one other possible use of carbon dioxide emissions. UAF researchers have received funding from the U.S. Department of Energy to study chemistry involved in using CO2 to recover gas hydrates.
The theory is that CO2 injected into a frozen gas hydrate formation will replace the methane contained in the clathrate — basically an ice-like cage. The methane will be freed for extraction and production, while the carbon dioxide would remain encased in the frozen structure.
“That procedure is a long shot … but that’s my dream scenario,” Wright said. “You are releasing additional methane by injecting CO2 in the clathrate. In addition to reducing emissions that industry produces, you’ve made more methane that can be put into the pipeline to sell.”
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