Simply reducing the amount of carbon dioxide that spews into the atmosphere each year isn’t enough to save the environment. We also need a way to get rid of what’s already out there.
This year, a team of engineers and scientists from Columbia University, the University of Iceland, and the University of Copenhagen figured out a way to do just that: They’ll turn the
gas into rock. In Iceland.
Because of Iceland’s volcanic activity Previously, geothermal plants there drill into the earth to tap volcanically heated water for power, releasing carbon dioxide and hydrogen sulfide. In the past, CO2 that escaped during this process was captured, then pumped back underground into former gas or oil reservoirs. That technique worked for awhile. But there was no way to guarantee that
people wouldn’t accidentally pierce those reservoirs in the future, releasing the stored CO2 back into the atmosphere. This new process ensures that that will never happen.
Now, the CO2 is still pumped underground, but first it is dissolved into water. The engineers pump the mixture into natural formations made of basalt—a porous lava rock that likes to react with carbon dioxide. When the water floods into the basalt, the carbon reacts with the rock to form a chalky mineral
called carbonate. It was previously thought that this process took hundreds or thousands of years, but the researchers have already found that it can happen extremely quickly. In two years, 90 percent of the injected CO2 has solidified. Because basalt is a common rock found all over the world, the team in Iceland thinks that this technique can be applied in many other countries. For
now, it may be costly, but so is running an air conditioner when it’s 120 degrees outside.