Research & Development
What if you could have an oil sands mine that didn’t require a tailings pond? That’s one of the possibilities scientists are exploring at Imperial Oil’s research facility in Calgary.
An open pit mine — anywhere in the world – is going to produce tailings — a mixture of water and materials left over from the processing of the resource (in the oil sands, about 20 per cent of the resource is surface mineable; the rest lies deep below the surface and requires in situ recovery methods).
“Mining the oil sands has been around for a long time,” says Ron Myers, manager of facilities and environment research at Imperial’s Calgary research facility. “There have been a lot of improvements and work that has gone into the process, but the bottom line is it still uses water. And anytime you use water, you’ll get tailings.”
Myers says scientists in his facility and elsewhere are exploring a number of different options to better manage tailings.
One option is aimed at developing improved technologies that address tailings produced from the current water based process.
“With the current process, the formation of tailings starts in extraction. As soon as caustic, warm water and mechanical energy are added to oil sands ore, fines are dispersed and you have to deal with them,” says Myers.
Ron Myers, manager of facilities and environment
research at Imperial's Calgary research centre.
Through research programs at the Canadian Oil Sands Network for Research and Development (CONRAD) and the Imperial Oil-Alberta Ingenuity Centre for Oil Sands Innovation at the University of Alberta (COSI), Imperial and other oil sands operators are supporting work aimed at reducing the amount of tailings that are produced. Research programs through CONRAD include fine tails settling, thickening and flocculation (how the tailings cluster together) – all in an effort to improve the capture of fine tailings.
Imperial’s researchers are also investigating innovative ways to capture and reclaim fine tailings from the water-based process while also recycling water and process heat.
Another option is to explore new ways to extract the bitumen that doesn’t use water — non-aqueous extraction. This method produces “dry,” stackable tailings that are ideally returned directly to the mine.
Myers says non-aqueous extraction could involve the use of solvents or even thermal approaches to extract bitumen. While he won’t get specific, Myers says scientists at Imperial’s research facility are working on some very interesting leads (and he suspects researchers elsewhere are also exploring options for non-aqueous extraction).
Imperial and others in the industry are working hard on the development of new technologies with improved environmental performance for mining the oil sands, says Myers. “It’s not going to happen over night. It’s a tough problem and a lot of smart people are working on it,” he says. “Through human ingenuity and innovation, industry will meet the challenge.”