A simpleton might ask, “If CO2 in our atmosphere is causing climate change, why don’t we
just put it underground?”
You idiot, you’re a genius.
Hi everybody, Julian here for DNews.
There are a lot of options for curbing CO2 production on the table, with my personal
favorite being not making any more of it.
But as it stands right now, we’re still very dependent on energy production methods
that pump billions of tons of it into the atmosphere annually.
Recently I made a DNews episode on a method natural gas plants can use to condense their
CO2, which makes it easier to pressurize it and store it underground.
But I wanted to follow up with a look at if that’s really a viable option.
Right now the idea is being put into action in Decatur, Illinois by Archer Daniels Midland.
They produce over 2,700 tons of CO2 daily as a byproduct of turning corn into ethanol.
For the last 3 years they’ve been pressurizing a third of that CO2 and pumping it into sandstone
2,100 meters below the surface.
The Carbon Dioxide is heated to 35 degrees celsius and pressurized to 9.8 megapascals.
At that temperature and pressure the molecules don’t act like a gas, but they don’t act
like a liquid either.
They’re whats called a supercritical fluid, with properties of both.
It can be pumped through a pipe, but when it reaches the sandstone sediment deep underground,
it effuses through the pores like a gas.
This property lets ADM pump 1,100 liters of Carbon Dioxide underground a minute.
Of course eventually the sandstone deposit underground will run out of pore space, but
right now it’s estimated this particular deposit can store centuries of emissions from
the upper midwest.
According to the US Geological Survey, there are enough sandstone sites around the US to
store American emissions for 500 years.
Great, let’s start drillin’ and fillin’ right?
Not so fast, there are possible downsides.
Recently headlines were made when studies showed conclusively that earthquakes in Ohio
were becoming more frequent because of hydraulic fracturing.
Fracking isn’t quite the same as this method of carbon capture and storage, Fracking involves
pumping water, sand, and other chemicals underground to break rocks and release natural gas.
Scientists believe the water may be causing slippages in hidden faults, or providing just
enough pressure to induce seismic activity.
With this in mind the USGS is monitoring seismic activity by the Decatur site and so far it
looks like the storage isn’t having negative effects topside, so ADM is planning on scaling
up and pumping all their CO2 underground.
Even if it works flawlessly here detractors aren’t certain other sites won’t be near
hidden faults, and we’re going to need a lot more places to put the carbon dioxide
if this is going to put a dent in how much we make.
Thousands more wells like the one in Decatur in fact.
So far ADM has pumped about a million tons underground but the US emits over 5 billion
tons of it annually.
Plus if the CO2 will find or open cracks in the bedrock above it and seep back out again,
the whole exercise is moot.
It’s not an immediate fix to the problem, and if it ends up causing more damage than
it prevents the plug may be pulled on this form of carbon storage entirely.
So for now it looks like the best solution is to reduce emissions where possible, work
towards carbon-neutral energy production, and steadily introduce carbon capture and
storage to cut down on how much we emit now.
CO2 isn’t just messing with the environment globally, it can also screw up your brain
if you’re stuck in a crowded room.
Matt’s video explains over here.
Have you been affected by earthquakes either natural or man-made?
If you’ve got a story or want us to look into it, share with us in the comments and
I’ll see you next time on DNews