University of Calgary researchers are investigating the use of Alberta-grown biomass—agricultural and forest crop residues (straw and wood)—to clean up chemical contaminants in produced water from oil sands operations. The researchers developed an activated biocarbon (or biochar) tailored for adsorbing the naphthenic acids in tailings pond water, preventing the formation and release of methane.
Previous studies showed that commercially available activated carbon products were very effective at removing organics from produced water obtained from oil sands operations. Now researchers are working to develop a novel way of making an activated or adsorbing biocarbon that can be produced at large scale from Alberta-grown biomass with much lower energy input and lower economic cost. The team successfully made small amounts of biochar from aspen residues using slow pyrolysis, a relatively low-temperature process that ‘burns’ the biomass in the absence of oxygen. For this project, the team scaled up their laboratory process to confirm final products are cost-efficient for the oil sands industry.
Dr. Layzell is collaborating with colleagues Dr. Josephine Hill, a chemical and petroleum engineering professor, and Dr. Andrei Veksha, a post-doctoral researcher who has expertise in making activated carbons.
Based on a preliminary study, estimates indicate that if the activated biochar is used to remediate tailings water in all oil sands mining operations, the lifecycle greenhouse gas benefit could be up to 345,000 tonnes of CO2e per year. If the biochar is used to remove organics from all produced water from SAGD oil sands operations, the GHG benefit could be as high as 2.4 million tonnes of CO2e per year. The ultimate GHG value of the biochar will depend primarily on how extensively it is used for water treatment and the energy efficiency of the process used to make the activated biochar.
ERA funded this project through the Biological GHG Management Program, administered by Alberta Innovates.