Capturing Carbon Dioxide
Wednesday, September 3, 2008 by Kyle Scribner
The massive volume of CO2 released by the burning of fossil fuels is poisoning our world. But we can’t just cut out use of coal and natural gas as energy sources – they’re too effective, cheap and plentiful, plus industrialized societies would pretty much grind to a halt if we did. So realistic save-the-environment approaches have us simply cutting back on fossil-fuel use, along with capturing and sequestering emissions. But what exactly does this “C02 sequestration” mean?
The Australian-based Cooperative Research Centre for Greenhouse Gas Technologies offers a nice summary of carbon capture and sequestration, and it basically boils down to this: Emissions from electricity plants and other factories contain a mix of pollutants, including that greenhouse darling CO2. There are certain technologies (I won’t go into here since just the names themselves – like “amine absorbers” and “cryogenic coolers” – already bored me, but if you are so inclined, you can read about them at MIT’s site for its sequestration program) that separate and capture the CO2, which can then be transported to sequestration sites in either land or sea. Thus, the CO2 never enters the atmosphere, locked away in a biological vault.
There’s also the natural way of doing things, such as optimizing forests’ ability to capture CO2 (pdf).
And then we have Stanford professor Brent Constantz, who is using a process similar to how coral reefs form to make “green cement,” according to the San Francisco Chronicle. As coral uses magnesium and calcium in seawater to create carbonates, Constantz’s method uses CO2 and seawater to make the carbonate that comprises cement. (However, coral reefs themselves aren’t a means of CO2 sequestration, Dr. James Cervino of the Woods Hole Oceanographic Institute warns, because they in fact release carbon dioxide.)
The Australian-based Cooperative Research Centre for Greenhouse Gas Technologies offers a nice summary of carbon capture and sequestration, and it basically boils down to this: Emissions from electricity plants and other factories contain a mix of pollutants, including that greenhouse darling CO2. There are certain technologies (I won’t go into here since just the names themselves – like “amine absorbers” and “cryogenic coolers” – already bored me, but if you are so inclined, you can read about them at MIT’s site for its sequestration program) that separate and capture the CO2, which can then be transported to sequestration sites in either land or sea. Thus, the CO2 never enters the atmosphere, locked away in a biological vault.
There’s also the natural way of doing things, such as optimizing forests’ ability to capture CO2 (pdf).
And then we have Stanford professor Brent Constantz, who is using a process similar to how coral reefs form to make “green cement,” according to the San Francisco Chronicle. As coral uses magnesium and calcium in seawater to create carbonates, Constantz’s method uses CO2 and seawater to make the carbonate that comprises cement. (However, coral reefs themselves aren’t a means of CO2 sequestration, Dr. James Cervino of the Woods Hole Oceanographic Institute warns, because they in fact release carbon dioxide.)
The creation of typical cement creates tons of CO2, so Constantz would set up his cement shops next to traditional factories and use their emissions to create his eco-cement, which sequesters the CO2.
What do you think? Is capturing and sequestering viable? Is it even enough? Let us know by commenting below.
Labels: carbon sequestering, CO2 capture, green cement
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Kyle Scribner is a born-again nature freak who also happens to be an editor at Captivate Network. 