Naked Science Forum
Life Sciences => The Environment => Topic started by: Tony McElroy on 20/11/2008 15:12:35
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Tony McElroy asked the Naked Scientists:
Hi guys. I'm quite a new subscriber to the show (http://www.thenakedscientists.com/HTML/podcasts/), but love listening to it every week.
I was really interested to hear the story about how CO2 can be locked away in rock. It's interesting to hear that the type of rock is in abundance in the biggest oil producing region. And this made me think that surely the Oil producers would jump on this method and make it a reality, as it would mean they could continue to produce Oil without having to worry so much about having CO2 cut backs imposed on them.
However, if it became a reality, it could also mean that we get lazy about cutting CO2 emissions as there would be a way of getting rid of the excess.
regards
Tony
What do you think?
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First of all.
The CO2 cycle from source to 'sink' is ca fifty years (or more).
So let's say we stop all man-made CO2 today, then it will still take at least fifty ears before the concentrations that are up there finally is down.
Under that time the Earths natural heat-sinks like oceans trees etc will have to take care of this increased amount.
And CO2 is not the only 'pollutant' here, we have methane (with a 12 years cycle) as well as other gases that are on a constant rise.
There are already reports from the arctics shallow waters, of methane releases 'bubbling up' as well as from the tundra in Siberia.
All of them with a much 'better' heat keeping value, from a twenty one times better (methane) and upwards.
(Or 'worse' if seen from a more humane standpoint:)...
Those frozen methane deposits that are in our 'warm' waters lies on a considerable larger depth (up to ten thousand meters).
If those were 'heated up' our atmosphere would cease to be.
Breathable that is:)
Our Oceans are now getting warmer down to around four thousand meters depth, and that is from last year, so what that number is now??
The Oceans waves are also moving faster due to a increased energy concentration (heat).
The acidity in the Oceans due to the CO2 uptake is constantly increasing, killing marine life.
The cold waters in the arctic keeping our first 'source' of food (plankton, krill) is disappearing.
And there are now over four hundred places worldwide that no longer contain life in our Oceans.
Fishing grounds.
Those rocks you are talking about?
Is it Peridotite?
Found in the Earth's mantle, or the layer directly below the crust.
So you're in for the deep dig then, a little like that book by Jule Verne:)
It may appear on the surface in Oman, but it is not any 'salvation' for mankind.
There are a lot of inventive ideas around, from pressing liquid CO2 down into 800 m deep storage locations where it is hoped that limestone will bind it.
"Although they may appear solid, most of these rocks are sedimentary and made of sand or carbonate pieces," explained Professor Haszeldine.
"About a third of the rock is space made up of microscopic pores, and this is where the CO2 seeps into."
Because the CO2 is buoyant, the storage area needs to have a geological "cap" to prevent the molecules escaping.
This means the location requires an impermeable layer, such as mud or clay, above the area where the CO2 is being pumped.
To using Oil and gas fields " Considered to be "secure vessels" because the sites have safely stored oil or gas for millions of years. A natural porous reservoir with an impermeable seal above it. Or Saline aquifers " The injected CO2 physically pushes the salt water out of the way before dissolving into the water over time, forming fizzy salty water."
What they all have in common is that they are ideas, of course we will need to test them, all of them.
But if this was in physics instead none of them would be called a theory.
They could only be named ideas, and as such worth about as much as the paper they were written on.
As long as nobody tested their premises.
Since when has vauge promises been 'truths'?
(Except from politicians of course)