New research now underway could virtually eliminate the use of freshwater in extracting bitumen from Alberta's oilsands.
By adapting existing technology, a University of Alberta associate professor and researcher believes that she can change the way bitumen, a thick, tar-like form of petroleum, is recovered, while at the same time making the industry more environmentally friendly.
And it all boils down to decaffeinated coffee - or at least the process behind it: Supercritical fluid extraction.
"Cleaning up contaminated soil using supercritical fluid is something that I've been working on for several years," says Selma Guigard, an associate professor in the department of civil and environmental engineering at the U of A.
|Photo courtesy of University of Alberta|
|University of Alberta associate professor Selma Guigard is in the early stages of developing a method that would cut down the use of fresh- water in extracting bitumen from the oilsands.|
"If I can extract petroleum products from contaminated soil, then I should be able to extract bitumen from oilsands."
Supercritical fluid extraction uses a fluid that is neither liquid nor gas but has intermediate properties of liquids and gases.
Guigard brings carbon dioxide past a certain temperature pressure so that it becomes a supercritical fluid. At that point, it has the right properties for extraction.
"There's been some work done in the literature, but nobody really followed through fully in the past because there were concerns that it could never work on a large scale," says Guigard. "Now technology has advanced so much ... that people are no longer worried that it can't be feasible at such a large scale."
She adds one example of successful supercritical fluid extraction on a large commercial scale is Maxwell House, which uses the technology in the decaffeination of coffee.
If Guigard is right - her research is in its early stages - she hopes to cut down dramatically the amount of freshwater used to remove gooey bitumen from the oilsands.
"We use lot of water to extract bitumen from the oilsands," she says. "We use between two to five barrels of freshwater for one barrel of oil or bitumen. With the technique I use, we would use much less to no water."
Guigard also thinks that the water remaining in existing tailings ponds - a byproduct of the bitumen extraction process - could be recycled and used if her method is adopted, instead of using continuous new supplies of fresh water.
The energy industry is very aware of the environmental concerns surrounding the oilsands, including the use of water, the release of greenhouse gas emissions and impacts on the land, says Brian Maynard, vice-president of stewardship and public affairs for the Calgary-based Canadian Association of Petroleum Producers.
Any technology that allows the industry to reduce its environmental impact is of interest, he adds.
"This is one of many technologies that are being pursued," says Maynard. "There may not be any one technology (solution). One technology may work better in one situation; another technology may work better in a different project."
However, he is confident such research will eventually produce the answers oilsands firms are seeking, and notes the industry has a long track record of research and innovation.
"Fifty years ago, the oilsands were not able to be developed from a technology perspective," Maynard says. "Since that time, the industry has committed a lot of brains and money to crack the technology to allow it to be developed on an economical basis.
"And I'm personally convinced it will be able to address the environmental concerns through the application of technology."
But it's not just preservation of water that has Guigard pumped about her research. Other potential benefits await, such such as changing the nature of the tailings ponds, which in turn could save wildlife.
"The important thing is this unfortunate event - the recent death of about 500 ducks that landed in an oilsands tailings pond with most dying after being covered in the oily residue - has basically made people, industry and government realize we need to do something about these tailings ponds," says Guigard.
"We can't just continue with the status quo. We need to investigate new technologies and new waterless technologies or technologies that use substantially less water."
While Guigard's work wouldn't eliminate tailings, it would make them less attractive to some wildlife as there would be no watery-like pond.
She adds it's too early to say how long it might take for her research to become a practical application in the oilsands. Such technology would be more costly when compared to existing extraction methods, with Guigard estimating a cost of $20 per barrel as opposed to the current $8 to $15 a barrel.
"We're looking for funding this for this," she adds. "We've done some preliminary modeling and some extractions and we're looking for funding to go to a full-fledged program. We've approached a few companies, but we haven't been able to secure the funding yet."
Guigard is working in collaboration with Warren Stiver, a University of Guelph professor and NSERC chair in environmental design engineering.
(Laura Severs can be reached at email@example.com)