Basalt formations may turn CO2 into limestone
New analysis of basalt rock formations on the Eastern Seaboard of the U.S. reveals the possibility of cleaner coal.
Wed, Jan 13, 2010 at 01:17 PM
Energy generated by coal-fired power plants will never be “clean," but what if it could be cleaner? A story from Popular Mechanics suggests that might be the case.
One aspect of coal's harsh environmental impact is the way it must be extracted. The felling of ancient forests, destruction of majestic mountaintops, and coal ash (or “slurry”) spills are just some of the problems associated with coal mining. The other aspect of coal’s eco-unfriendliness is the monolithic amount of carbon dioxide released when it is burned.
The latter is the target of a new scientific analysis. It’s basically a new spin on the old idea: carbon sequestration — capturing and storing CO2 deep underground — with a focus on basalt rock formations on the coasts of New York, New Jersey and Massachusetts.
The Popular Mechanics article says, “Early Dutch New Yorkers called the staircase-like basalt of the Palisades ‘trap rock’; not because it trapped anything, but after their native word for ’step’. But a new scientific analysis suggests that the related basalt formations buried under the U.S. East Coast and extending out to sea might someday be doing some critical trapping after all — of greenhouse gas emissions from the likes of giant coal-burning power plants.”
The results of the analysis where published last month in The Proceedings of National Academy of Sciences and suggest that the basalt formations actually may be ideal for locking up billions of tons of CO2. As a matter of fact, a single basalt formation just south of New York City is has the estimated potential to store 900 million tons of CO2 — or 40 years of emissions from three to four coal-fired power plants.
According to data from 2005, SourceWatch.org says the U.S. alone has 400+ coal-fired power plants. Could the basalt formations worldwide hold the globe's coal-fired power plant emissions? It’s too early to tell.
So what makes the basalt formations such good CO2 traps?
The Popular Mechanics story says, “Basalt, it turns out, is capable of performing what seems like sheer alchemy: It can transform normally buoyant CO2 dissolved in water into something decidedly non-buoyant — solid rock. Essentially, a series of chemical reactions combines carbon dioxide with calcium in the basalt to form calcium carbonate, or limestone.”
One of the biggest points of contention with this solution has been the fear that the gases won't stay locked away in the Earth forever — and would one day escape to enact their revenge on humanity … Clash of the Titans style. Experts say the massive capture and storage of carbon would create a stimulus to continue using fossil fuels instead of focusing on new, cleaner energy sources.