Lee Spangler holds up a small sandstone rock that he says could suck up carbon dioxide like a sponge. Rocks like this could play an important role in the fight against climate change, he says. At the same time, the technology could help out the coal industry, one of the biggest emitters of CO2.
"That's where you put the CO2, in something that feels like solid rock," said Spangler, a physical chemist who runs Montana State University's Energy Research Institute in Bozeman.
Spangler heads the Big Sky Carbon Sequestration Partnership, which is studying the viability of storing liquefied CO2 from industrial facilities such as coal-fired power plants in porous rocks thousands of feet below the surface in Montana and five other Western states.
Sequestration is not putting CO2 in underground caves, a common misperception, he says. Invisible holes in rocks are the storage grounds.
"It's important to look carefully to see if this can be part of the solution," Spangler said. "Right now, I would say the evidence is pretty good that it could be."
Since 2003, $79 million in federal funds have poured into the U.S. Department of Energy-backed sequestration project, which involves mapping potential sequestration sites and CO2 sources and conducting tests on how well rocks will trap the pollution indefinitely. MSU's is one of eight regional sequestration research efforts nationwide.
The technology isn't ready for prime time but large-volume test injections of more than 1 million tons are in the works.