Carbon capture utilization and storage has been identified as one of the tools needed to prevent CO2 from hard-to-abate industrial processes getting into the atmosphere.
“CCS is an option to reduce emissions from large-scale fossil-based energy and industry sources, provided geological storage is available," the Intergovernmental Panel on Climate Change’s Working Group 3 said in its sixth assessment last year.
That caveat -- "provided geological storage is available" -- is an important one. Capturing CO2 is one thing -- finding a place to permanently store it is a whole other challenge.
Whereas there is good geological storage potential in Northeastern B.C., what would you do with CO2 captured from industrial flu stacks here in the Lower Mainland?
Scientists from Simon Fraser University and the University of Calgary are going to be trying to answer that question with a novel approach to underground CO2 sequestration.
Shahin Dashtgard, a scientist with SFU’s Earth Sciences department, has received $399,070 from the Natural Sciences and Engineering Research Council of Canada (NSERC) and $500,000 from the B.C. Ministry of Energy, Mines and Low Carbon Innovation to assess the potential for CO2 geological sequestration in the Lower Mainland.
“Our goal is to identify areas within the subsurface with the highest potential for long-term storage of large volumes of CO2,” Dashtgard said in an SFU news release. “We’re considering a novel approach – a made-in-B.C. solution.”
That made-in-B.C. solution is literally a solution: a solution of fizzy water infused with CO2.
“We're looking at dissolving CO2 in water like a soft-drink and then storing that CO2-rich brine solution between a thousand and two thousand metres deep underground,” Dashtgard said.
Alberta and Northeastern B.C. have good geology for underground storage of CO2, where fine-grained and impermeable rock formations provide the right conditions for permanently storing CO2 deep underground. The rock under the Lower Mainland is porous, making it less ideal for holding CO2 in place underground.
The solution Dashtgard is exploring is storing CO2 in deep underground aquifers. Water at depths of 1,000 metres or more contains a high amount of salts, making it unpotable and unsuited for agricultural use, and high high pressure at those depths would keep the CO2 dissolved.
“The high pressure deep underground will keep the CO2 dissolved in this brine solution, which is denser than the brine in the rock, causing it to sink,” SFU explains in a news release.
Part of Dashtgard’s work will be to study fault lines and seismic activity to determine which underground wells would be less vulnerable to seismic activity.
Once mapping is done, Dashtgard and his team will identify which sites have the best potential for CO2 sequestration and then work with Hassan Hassanzadeh, a professor of Chemical and Petroleum Engineering at University of Calgary, to develop simulations for how the stored CO2 might behave over short and long periods of time.
The data developed from the study on temperature, pressure, and fluid flow might also be useful for identifying geothermal energy potential in the region.
“Our mandate is to share our data so people can see the information used to build our model,” Dashtgard said. “We will give the academic community and companies a sense of how you would carry out a CO2 sequestration evaluation in a tectonically active region.
“We’re adding a massive amount of information about what the subsurface below the Lower Mainland looks like, and the process to make a project like this work.”
