The technology would return clean tailings pond water to the environment
Markham Hislop is Editor in Chief of Beacon News.
CALGARY, AB, Jun 18, 2013/ Troy Media/ – Researchers at two Alberta universities believe they have found the solution to a major oil sands problem: the environmental risk posed by tailings ponds.
Oil sands mining operations use a lot of water, two to four and a half units for every unit of synthetic crude they produce. The Alberta government permits oil sands companies to divert 1.3 per cent of the Athabasca River’s annual flow, which is 359 million metres cubed, twice what the entire city of Calgary uses. Even though that water is recycled multiple times, the recycling concentrates toxins and metals left over from extracting and upgrading the bitumen, resulting in tailings ponds that are a significant risk to the environment.
Biologists at the University of Calgary and engineers at the University of Alberta say they have developed a “biofilm,” a kind of bacterial growth laymen generally refer to as slime. Two years into the research, both groups are excited about their progress. A paper into the first round of research will be published in the January edition of FEMS Microbiology Ecology.
The oil sands’ fine tailings and processed water were placed in the wells of the Calgary Biofilm Device to see if biofilms would grow. The darker colouration is the organics and oil droplets, and bacteria biofilms are growing on the droplets.
Biofilms are everywhere in our environment, including in the plaque on our teeth and can be very resilient, says Dr. Raymond Turner, a professor in the Department of Biological Sciences at the University of Calgary.
“We’ve isolated biofilms that are indigenous to the oil sands’ environment and are highly tolerant to the stress associated with toxins and metals found in tailings water. Those consortia of biofilms are able to, slowly, detoxify the water,” said Turner, who co-leads the project with Dr. Howard Ceri, biological professor at the University of Calgary.
“Consider how much work you do to keep your teeth clean,” said Turner. “It is this tough quality that we believed would be great idea to exploit.”
A sample of sediment, or sludge, was taken from a tailings pond in the summer of 2009. MSc candidate and paper co-author Susanne Golby was able to successfully cultivate biofilms from the sample under a variety of different conditions.
“It was really exciting when we found that multiple different species could be recovered within one biofilm. By altering the growth conditions, and exposing the biofilms to different stressors, we could select for or against certain species and we began to learn how we could manipulate the biofilms to get the metabolic activities and characteristics we were looking for,” said Turner.
Turner likens the organisms to a team of workers on a job site.
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