Canadian researchers develop new oilsands cleaning method
By Design Engineering StaffGeneral engineering environment oilsands University of Calgary
Water treatment plants for all oilsands operations envisioned.
It’s no secret that oilsands development has an environmental problem. Such projects use vast amounts of water and recycling it only concentrates the toxins and metals leftover from extracting and upgrading the bitumen. The result is tailings ponds that can pose a significant risk to the environment.
However, biologists at the University of Calgary and engineers at the University of Alberta have teamed up on a research project to help resolve the water issue. The team’s NSERC-funded research uses biofilms, a common but resilient form of bacterial growth to settle the tailings sludge and clean the water.
“We’ve isolated biofilms that are indigenous to the oilsands 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,” says Dr. Raymond Turner, a professor in the Department of Biological Sciences at the University of Calgary, who co-leads the project with Dr. Howard Ceri, biological professor at the University of Calgary.
As part of their research, 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,” Golby said. “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.”
Turner and his team are now actively growing biofilms on the support material to test in bioreactors, which are being developed by professors and their graduate students in the Department of Civil and Environmental Engineering at University of Alberta.
The ultimate goal, says Turner, is to develop tailings water treatment plants for all the oil sands operations. “The plant would take all tailings water, completely clean it, and return it to the river system. Just like wastewater in Calgary is cleaned and returned to the Bow River.”
A paper into the first round of research will be published in the January edition of FEMS Microbiology Ecology.