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New Material Can Selectively Capture CO2
Socguy brings us a story from CBC News about a recently developed crystal that can soak up carbon dioxide gas "like a sponge." Chemists from UCLA believe that the crystals will become a cheap, stable method to absorb emissions at power plants. We discussed a prototype for another CO2 extraction device last year. Quoting:
"'The technical challenge of selectively removing carbon dioxide has been overcome,' said UCLA chemistry professor Omar Yaghi in a statement. The porous structures can be heated to high temperatures without decomposing and can be boiled in water or solvents for a week and remain stable, making them suitable for use in hot, energy-producing environments like power plants. The highly porous crystals also had what the researchers called 'extraordinary capacity for storing CO2': one litre of the crystals could store about 83 litres of CO2."
That's 83 liters at STP.
Carbon dioxide weighs in at 1.98 grams/L at STP.
1.98*83 = 164.34 grams
They're absorbing 164.34 grams in 1 liter of the crystals. Definitely underwhelming.
There are 11 types of people. Those who understand binary, those who don't and those who are sick of this lame joke.
- The average US household produces 7.5 tons of CO2 equivalents per year.
- The density of C02 is 1.799 kg/m3
- So the average US household produces about 7.5*1000/1.799 m3 of CO2 = 4,169 m3 = 4,169,000 litres
- One litre of the crystals could store about 83 litres of CO2.
- So per family requires 4,169,000/83 = 50,228 litres of crystals per year
- I guestimate the average house (of say 10 rooms) has a floorspace of about 1500 ft2 = 150 m2, with each room being 10 ft or 3 m high,
- So the average house is 450 m3 = 450,000 litres, split between 10 rooms.
These crystals would about fill one room of every house every year, floor-to-ceiling.As about half the other commentators have already said, this does not allow for the financial and environmental costs of producing these crystals.
They might even cost more CO2 to produce than they store.
Reduce, reuse, cycle
I doubt that long term studies have been completed. It doesn't seem like ZIFs are extremely new, this process for creating them and this particular variation are new. That said, several other sources provide better information than the CBC link and speak directly to your question. The CBC article states in first paragraph: "the crystals are non-toxic and would require little extra energy from a power plant."
http://www.sciencedaily.com/releases/2008/02/080214144344.htm/ Suggests that this looks much cleaner than existing state of the art:
Yaghi's initial idea of what to do with the material afterwards appears to involve geologic storage.
It's also always useful to hunt down the primary source. I think this PDF is it (I only skimmed).
My motto: "A cat is no trade for integrity."
Well, you get up to 21 pounds of CO2 from a pound of crude oil - a 21:1 increase in "stuff". This sponge apparently can do a 1:83 reverse, so the whole system appears to be a 21:83 savings in space underground. Why not pump it right back into the ground?
That is so wrong that I am forced to suspend your Slashdot license.
First, that page page doesn't say "pound of crude oil"; it says "gallon". That's like 7.5 pounds of oil. So that's a 3x increase in stuff. (Which some would call "mass".) Then these crystals do 1:83 in volume, but more like 10:11 in mass. So to get rid of your pound of crude oil, you'd need about 30 pounds of these crystals.
Please go study Dimensional Analysis (aka the unit-factor method or the factor-label method). Once you have mastered that, you will be permitted to post on science-y topics again.
I once worked at a materials lab that studied how things hold up in a marine environment, and I grew up on the ocean. Nothing lasts very long. Not stainless steel, not titanium, and certainly not any kind of mechanism. Constant maintenance and replacement is required in a marine environment, and this is one of the reasons that tidal power has been so slow in coming.
And this is without getting into big storms, which can wipe out a whole island - let alone some man-made fixture.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Dude, you really need to cut back on the hydro, in more ways than one.
A pyramid is a static structure. All it has to do is sit year after year.
A power-generating station is full of moving parts. Things with moving parts break down over time. You may want to look at this handy informational link which shows maintenance over time on our local power plant. (since it's run by falling water, it provides some of the world's cheapest power, regardless)
When you start talking about tidal power, you are talking about putting devices which sit in salt water day after day. Go find someone who owns a boat. ANY boat, large, small, freighter or dinghy and talk about this idea of "set it and forget it". Watch as peals of laughter come rolling from their mouth. Boat owners in this part of the world (US Pacific Northwest) will pay a substantial rental premium to moor their boats in fresh water because it saves so much money on maintenance.
Finally, remember that electricity is like no other commodity on earth. You can not store it for a rainy day. You use it when it's generated, or not at all. Even fish (our other highly perishable commodity) can be canned or packed in salt. Good luck doing that with electricity.
Yes, oil gets some subsidies. Yes, euphemistically named "energy companies" almost certainly throw their weight around to discourage development of alternative energy sources. These are fairly small market-distorting effects which reinforce (but do not change) an underlying fact: historically, petroleum has been the cheapest and most flexible means of generating energy. While we get spoiled in this part of the world by abundant hydropower, there are some fairly serious environmental consequences (check out our vanishing salmon runs!) and hydro is a one-off. Once you've dammed the river, you're done. You can't scale this solution forever.
While more needs to be done with alternative energy sources, there seems to be this meme running around that there is cheap power floating around which is being withheld from the people by "The Man". Standing in the way of that cheap power in reality is not some gigantic conspiracy, but some really tough unsolved engineering problems (i.e. how do you store enough energy to power a city for when the sun don't shine or the wind don't blow? A big pile of batteries doesn't really work).
They still are. But you, like so many others, seem to be completely ignorant of the concept of rate of change. Humans are changing the CO2 levels orders of magnitude faster than natural factors have in the past, so those effects get lost in the noise.
So "humans are emitting lots of CO2" does cut it.