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This is a set of questions related to one I asked recently. It's about the pace at which a single device could remove Carbon Dioxide from the atmosphere.
Assume a device with an orifice a kilometer in diameter is placed at altitude one kilometer and pulls air through it at a rate of 100 kilometers per hour, transforming all of the Carbon Dioxide and some of the water vapor in it into a precipitable chemical (Just assume this part for now) before returning it. How long would it take before CO2 levels would be at pre-industrial levels? Assume the atmosphere mixes perfectly.
What would be the power expended in the fan of such a device?
What would be the ideal chemical for precipitation, what would be the process chemically, and what would be the power expended in doing this at the same pace as the capture process?
Assuming that a fraction f of the sunlight is used from it, what size array of mirrors parallel to Earth in orbit would produce the power of the processes above?
I don't know if anyone can get the middle part involving the chemical process, but I'd like to see if the other parts have reasonable answers. —Preceding unsigned comment added by Julzes (talk • contribs) 18:36, January 10, 2010
As for as the chemical part of your question: There is no chemical that can do the job, not without a massive input of energy. And if you had such energy available, just use it and let plants take care of the CO2 in the air.
I know these questions are interesting, but trying to find a way remove CO2 from the air is not necessary. What's necessary is finding a source of energy that does not involve hydrocarbons. If we did that, plants would take care of the CO2 in the air for us. And of course we have such an energy source, but it's slightly more expensive than hydrocarbons. Ariel. (talk) 23:42, 10 January 2010 (UTC)
Okay, as a follow up, set the question at pre-WW2 levels, double that from 'diameter' to 'radius', assume re-forestation accompanies it so that as much land as is available is (small) forest in 40 years (This may be the hardest part to calculate), and refute the non-sensical claims on chemistry and what is needed by Ariel. Then what's the time period? And, by the way, the solar array is envisioned as being transported in thin pieces stacked like potato chips in a can and then robotically spread out and used for a massive solar furnace. Is the idea for a beam directed at effectively one small area (top of mount Chimborazo) manageable with what is known of high-temperature optics? Directing optics are needed using at least three satellites.Julzes (talk) 00:48, 11 January 2010 (UTC)
Make it a mile in diameter, half a mile altitude (Don't ignore the altitude, but do assume the outflow is at significant distance), and 80 miles per hour. This was the original set of conditions that I thought up. It is quite clear that pre-WW2 and re-forestation must be added to get close to a reasonable time. The conversion to a hydrocarbon of density sufficiently greater than air--is that endo- or exoergic?Julzes (talk) 01:03, 11 January 2010 (UTC)
I'll take a look at that. Thanks, it may be a piece of the puzzle.Julzes (talk) 01:36, 11 January 2010 (UTC)
Thanks. I and plenty of other people disagree with your claims. Current levels are responsible for past changes already. See graph and the introduction at global warming. Make my preferred specific date of 1932, and assume a long-term leveling of what needs to be combatted at 2020 current projections (continued rise in emissions to a leveling). Assume for forestation that as many trees as were on Earth and have been lost since 1932 (suicides of Hitler's niece and Stalin's wife) are replaced and allowed to start growing in 2020, just as an average planting date, for both CO2-level dates. Assume algae and the rest of the flora are also functioning at the same date's level (in addition, since small trees won't fit that).Julzes (talk) 01:32, 11 January 2010 (UTC)
Actual warming lags behind CO2 (and CH4, which may all dump into the atmosphere from more than one source over a short time-period), and you haven't read through it all if that's what you think. I really must disagree.Julzes (talk) 01:51, 11 January 2010 (UTC)
Rule out the need for any energy to be used at all for separation of CO2 and do or do not consider the idea of conversion to a precipitate as an alternative to sequestration, as you prefer. There is no energy required for separation, as whatever excess heat there is in the processes may be directed to a ground site (at the equator) for reaching 40-degrees Celsius (as per the reference given on artificial trees above).Julzes (talk) 02:03, 11 January 2010 (UTC)
I think I've met you halfway on this, and you have been sounding consistently intellectually rude (and ill-informed on the subject of global warming) since my last post. At any rate, how do you yourself know that change in humidity cannot be used for this rather than a small tree? I'll grant it's true, if you will explain this, as I am genuinely interested in preventing the catastrophe that I know is imminent (in generational terms, neither hstorical nor next-year terms).Julzes (talk) 03:11, 11 January 2010 (UTC)
I'm all for the cleanest nuclear fission as well as all the others at the same time, by the way, but I am quite convinced we will need to and will be scrubbing the atmosphere as well. I've actually put a bit of thought (if not actual hard-headed research) into the question, and you haven't said a single thing that might enlighten me until this comment about humidity and scale.Julzes (talk) 03:22, 11 January 2010 (UTC)
Oh, I do appreciate your calculation, FWIW. I'll check up on the whole calculation as it proceeds here.Julzes (talk) 03:25, 11 January 2010 (UTC)
Never mind trying to explain that changes of humidity can't be used for something this scale. That's false or I'll eat my shorts.Julzes (talk) 03:34, 11 January 2010 (UTC)
Everybody keep in mind that using energy at the location at which it is generated is much much more efficient than building infrastructure for transmission and for transmission itself. That said, once this devoted device had fulfilled its initial purpose, it could be used for Latin American energy needs.Julzes (talk) 03:38, 11 January 2010 (UTC)
One thing I'm a little interested in that I don't know about as well is whether space-to-ground transmission would best be accomplished by something changing the spectrum of the Sun's light--microwave or something.Julzes (talk) 04:17, 11 January 2010 (UTC)
I'm also aware of research that shows that CO2 passed over a certain heated catalyst be used to make gasoline. If, as I assume, transformation to a precipitable chemical is innately endoergic, I will have fully conceded that sequestration and/or passing the gas over flora or a more efficient converter (in the future) in an intelligently designed system should be given the higher attention.Julzes (talk) 04:17, 11 January 2010 (UTC)
What part of what I said didn't you understand? Maybe the word 'heated', perhaps. At any rate, when I said 'familiar' I should have hedged a little bit and the purpose of the process was not to generate energy out of nothing. Last I saw, there were not 'several' laws of thermodynamics, and I could continue with this. You obviously didn't understand the word 'endoergic' (or at least the sentence containing it). You needn't have replied so strenuously, your statement about Carbon Dioxide seems quite the logic I would use, and we're both basically on the same page about how bad things are.Julzes (talk) 06:34, 11 January 2010 (UTC)
Hold on now, I'm not convinced about the logic on burning. The same logic says that obviously such an apparently weak process as photosynthesis shouldn't be able to make anything for life out of the Carbon. I imagine that CO2 is near minimum energy for the constituent elements, but to consider it rock bottom even with access to other elements doesn't sound right, at least to me. It's really almost the only thing fueling life itself (not human needs) on this planet.Julzes (talk) 06:45, 11 January 2010 (UTC)
I'll buy that if things go really badly.Julzes (talk) 08:03, 11 January 2010 (UTC)
The energetics of CO2<--->C(graphite)+O2 are such that the compound on the left is more apt to turn into the mixture on the right than the reverse, right?Julzes (talk) 08:09, 11 January 2010 (UTC)That's what it looks like to me if it takes something like chromic acid to oxidize graphite (allotropes of carbon).Julzes (talk) 08:29, 11 January 2010 (UTC)
I'm sorry, but I just don't see any hydrogen here. What you seem to say is heating oxygen gas and graphite with nothing else present will produce Carbon Dioxide. I suggest you try lighting some graphite (or diamond since it is less stable) on fire. The word is 'endoergic' (or endothermic if you prefer). Leave this question permanently, please. You seem like you don't know what you are talking about. I won't ask you again.Julzes (talk) 09:06, 11 January 2010 (UTC)
That's right, 'endogenic' was the wrong word.Julzes (talk) 09:27, 11 January 2010 (UTC)
It looks like Ariel might be (a little) right here. The enthalpy of formation of CO2 is the same sign as that of water, which definitely means that graphite will burn; so I've asked a question about that below. (I have to say s/he has hardly been helpful and doesn't understand the situation all that well, FWIW.)Julzes (talk) 10:00, 11 January 2010 (UTC)
Thanks. Well, I can fully erase the question below, since your post is just about as close as one could get to a direct answer to that one.Julzes (talk) 10:19, 11 January 2010 (UTC)
One logical possibility is that the optimal solution involves the conversion of some of the air into fertilizer. At any rate, whatever the full solution is is not likely to be found here.Julzes (talk) 12:25, 11 January 2010 (UTC)
The question was reposed at the top. If anyone wants to answer or see what answer is given, that is the place to go. Leave the earlier part alone or fold it up on my request if you know how to do it properly.Julzes (talk) 01:42, 12 January 2010 (UTC)
I'm fine with closing up that long part that got off topic, as I asked it to be partially closed rather than fully (in the hidden part).Julzes (talk) 02:38, 12 January 2010 (UTC)
At WMC's talk space, I've thrown in another condition for calculation for comparison purposes that might get around the same teperature. It's more complicated still, but perhaps it can be done. Still get the time period under identical conditions but for 1979 as the date in place of 1932 and with cool roof (reflective) technology being uniformly brought to universality in 2030. So, two sets of conditions wanting the time period required and also whether this later set of conditions is as cool as 1932 conditions would be. The second set should be much faster and it also requires a less dubious condition on flora restoration.Julzes (talk) 17:36, 12 January 2010 (UTC)
I can understand this question not getting much attention at this point. What I cannot understand is why nobody knew or bothered to state that both Magnesium Carbonate and Calcium Carbonate creation releases energy from Carbon Dioxide. Hmph!! Julzes (talk) 14:27, 13 January 2010 (UTC)
Well a little elucidation of the whole question could have been a good thing. Anyway, the claim that CO2 is pretty much rock bottom for Carbon was wrong. Now, combining anything naturally occurring with CO2 to get a release of energy may be impossible on a large enough scale, but to treat that as obvious is a bit superficial.Julzes (talk) 17:21, 13 January 2010 (UTC)
You seem to me to be misinterpreting what Ariel was doing.Julzes (talk) 17:05, 14 January 2010 (UTC)
I'm wondering if there has ever been a case of a human with hair (obviously head hair would be the best candidate here) that showed signs of being striped, dotted, or somehow patterned in the way other mammals (zebra, cheetah, panda) are, presumably due to the mutation of a certain gene/genes. If not in humans, perhaps in an animal that, like humans, is known for having single-tone fur (polar bear, squirrel?, lion?). I am of course referring to naturally occurring phenomenon, not like lion-zebra hybrids : D. 219.102.221.49 (talk) 02:18, 11 January 2010 (UTC)
Thanks for the responses! 219.102.221.49 (talk) 03:47, 11 January 2010 (UTC)
I've been spending a lot of time thinking about mirrors lately (the normal, flat, glass-fronted, silver-backed kind), and I find the idea of a mirror's color to be very strange: While the mirror is reflecting a 100% accurate picture of me, I still know, without being told, that the mirror is also silver colored at the same time.
How is this possible? How is the mirror reflecting a complete image of me and my surroundings (and their completely non-silver colors) and I still have this niggling (almost subconscious) knowledge that the mirror is silver at the same time? ~fl 03:43, 11 January 2010 (UTC)
Which lowers the spread of bacteria from a toilet flush? Putting the lid down or leaving it up? Does leaving it up directly expose its surroundings or does leaving it down incubate the aerosol after a flush?--99.11.199.76 (talk) 03:49, 11 January 2010 (UTC)
Does this compound exist? Or does it too easily convert to benzene? (I hate it when you google volatile compounds like that and they don't tell you why it doesn't exist.) John Riemann Soong (talk) 04:20, 11 January 2010 (UTC)
What is the the average mass of a Carbon atom in graphite plus the mass of an Oxygen molecule minus the mass of a Carbon Dioxide molecule to as high a precision as known at present? I know that there is mass in the motions of the electrons and I'd like to know if the one-and-a-half single bonds plus whatever the other half bond of the floating electron is called in Graphite is heavier or lighter than one of the double bonds in CO2 and by how much. A scaled up answer is fine. I can handle the basic stuff.Julzes (talk) 09:44, 11 January 2010 (UTC)
What temperature is required to burn transform Oxygen gas plus Graphite into Carbon Dioxide, as I now see it can be done from standard enthalpy of formation (and burning is the wrong word)? What is the activation energy?Julzes (talk) 10:12, 11 January 2010 (UTC)
Dragon'sFlight gave plenty of detail on this just when I was asking it in the other question I asked. Thanks anyway.Julzes (talk) 10:17, 11 January 2010 (UTC)
I'm having trouble finding biographical information about Yale botanist F. B. H. Brown, also known as Forest Brown, sometimes as Forest B. H. Brown. There seems to be someone of the same name who worked for the USDA or some other government organization, but I'm not sure if it is him or his father, or a relative or someone else entirely. If anyone can point me in the right direction, that would be great. Viriditas (talk) 10:07, 11 January 2010 (UTC)
Like, I'm actually trying to find what I thought would be a relatively simple compound, that is, 1,3-dioxobutane. Unfortunately, 1,3-dioxobutane doesn't seem to be used that often (either as the name or the chemical), so now I try some aldehyde nomenclature.
"If replacing the aldehyde group with a carboxyl group (-COOH) would yield a carboxylic acid with a trivial name, the aldehyde may be named by replacing the suffix -ic acid or -oic acid in this trivial name by -aldehyde. For example:"
So ooh, I could use acetoacetic acid, and then back-form acetoacetaldehyde, right?? Well, apparently googling this gives a KETONE, not an aldehyde. Someone please explain the insanity of this nomenclature. John Riemann Soong (talk) 15:26, 11 January 2010 (UTC)
In the proton NMR spectrum for RuClH(CO)(PPh3)3 there is doublet of triplets (two sets of three peaks, with the peaks in the ratio 1:2:1) at about -7ppm. It is clear that this is the hydride ligand on the ruthenium, but I do not know why it has split in such a way. I understand that phosphorus will split the peak, but I cannot see how it is possible to end up with a doublet of triplets. Similarly, how would the splitting pattern be if there were two hydrides instead of the a hydride and a chloride? 188.221.55.165 (talk) 16:22, 11 January 2010 (UTC)
Watching a show on the train 7551 derailment, I got to wondering about the trona it was carrying. The NTSB says it's "used in the manufacture of fertilizer".[4] Our article just says that trona is a source of soda ash (sodium carbonate). Our sodium carbonate article mentions use for making glass, melting flesh off skulls, use in both bricks and food (comforting that) but nothing about fertilizer. Except one mention of a modification of the Solvay process (which trona mineral bypasses anyway) where the "byproduct" ammonium chloride can be used as a fertilizer. Our ammonium chloride article mentions use in oil wells, food, explosives - but not in fertilizer.
So what am I missing? How is trona used to make fertilizer? And how is ammonium chloride used to make fertilizer? Franamax (talk) 16:27, 11 January 2010 (UTC)
Is there any unbiased scientific evidence that ingesting protein shakes while practicing an exercising regimen increases the amount of muscle tissue built up? By unbiased I mean studies not performed or funded by companies/parties with interest in protein shake sales. Something tells me all they do is fortify one's poop. 71.161.49.93 (talk) 23:44, 11 January 2010 (UTC)