As greenhouse gasses threaten the stability of our atmosphere, it is becoming increasingly critical to limit carbon dioxide emissions. A promising way climate scientists have proposed emission reduction is through mineralization: the process of turning carbon dioxide into solid rock to prevent it from reaching the atmosphere. This week, we spoke with Dr. Rob Jackson about this method of carbon capture. For a transcript, please visit https://climatebreak.org/carbon-capture-mineralization-with-dr-rob-jackson/
What is carbon mineralization?
As defined by the U.S. Geological Survey, “carbon mineralization is the process by which carbon dioxide becomes a solid mineral, such as a carbonate…The biggest advantage of carbon mineralization is that the carbon cannot escape back to the atmosphere.” This generally occurs by injecting carbon dioxide underground into certain rock formations so the carbon dioxide takes on a solid form: trapped and unable to reach the atmosphere.
How does carbon mineralization work?
Two of the main methods in which carbon mineralization occurs are ex-situ carbon mineralization and in-situ carbon mineralization. With ex-situ carbon mineralization, carbon dioxide solids are transported to a site to react with fluids—like water—and gas. In-situ carbon mineralization is the opposite—fluids containing carbon dioxide are funneled through rock formations in which it solidifies. Both of these methods result in carbon dioxide trapped in a solidified form.
In a third method of carbon mineralization, surificial mineralization, carbon dioxide reacts with alkaline substances—such as mine tailings, smelter slags, or sedimentary formations—which result in the carbon dioxide taking on a solidified form. In the case of in-situ carbon mineralization or surificial mineralization, carbon dioxide can react with surface water rather than an artificial fluid, replicating natural processes of carbon mineralization.
Currently, the biggest drawbacks and barriers preventing carbon mineralization from taking hold as a major climate solution lie in cost and research uncertainties regarding environmental risks. In terms of cost, the price for carbon mineralization is high: 5 million dollars per well to inject carbon dioxide into rock formations. Further, the risks for groundwater and its susceptibility to contamination through this method is unknown, and the potential side effects of contaminating water formations could be devastating for ecological communities which thrive off of these water systems.
Who is our guest?
Dr. Rob Jackson is a professor and senior research fellow at Stanford University, and author of Into the Clear Blue Sky, a novel on climate solutions. His lab focuses on using scientific knowledge to shape climate policies and reduce the environmental footprint of human activities. Currently, he chairs the Global Carbon Project, an effort to measure and control greenhouse gas emissions.
Resources
For a transcript, please visit https://climatebreak.org/carbon-capture-mineralization-with-dr-rob-jackson/
Ethan: I'm Ethan Elkind, and this is Climate Break: Climate solutions in a hurry. Today’s proposal? Drawing down carbon dioxide from the atmosphere by using a process called mineralization. Dr. Rob Jackson, chair of the Global Carbon Project, explains how it works, and why he thinks it’s a promising method for carbon removal.
Dr. Jackson: I went to Iceland, to visit a geothermal plant, where carbon dioxide has been bubbling out of the ground with the water that they use to generate steam and use for heating. And so, companies there are using carbon capture technologies not just to put that carbon dioxide back into the ground, but to draw CO2 down from the atmosphere.
Ethan: This mineralization process locks away carbon permanently, so it can’t escape back into the atmosphere. Jackson summarizes the process.
Dr. Jackson: They’re essentially making fizzy water, like a kitchen seltzer machine. They put this carbon dioxide into water, under pressure, so it’s bubbly. They pump that water underground, and, lo and behold, the carbon dioxide precipitates, and in only a year or two, it literally turns to stone. And the, uh, interviewer and engineer from Iceland said: “It’s not rocket science—it’s rock science.” There's a lot of hope and a lot of opportunity to make a difference in our lives. So don’t despair, I think about going from climate despair, to climate repair.
Ethan: To learn more about Mineralization and how it can store carbon in rocks, visit climatebreak.org.