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Atmospheric CO2 removal technologies?

  1. Jun 24, 2015 #1
    Are there any legitimate candidates for technologies that might provide inverse leverage over atmospheric CO2 levels? Super trees, Algae towers, I don't know, anything at all?

    I'm just asking about atmospheric control technologies, not about climate change per-se.

    of course the wiki has some stuff...
    Last edited: Jun 24, 2015
  2. jcsd
  3. Jun 24, 2015 #2
    Any technology which could be capable of significantly altering CO2 levels globally would have to applied on a massive scale and would take a very long time to be effective.
    Think about it - although CO2 level is rising and human activity is highly likely to be contributing factor, it has taken nearly 200 years of industrialisation for the changing level of CO2 to become a matter of serious concern.
    On a global scale as would be required, I think it's likely that some kind of bio engineering would be more effective than something like chemically processing air.
  4. Jun 24, 2015 #3
    Yeah, clearly it's a scale problem. Makes it seem like a cross between a "vast long plan" and some... things is required. I'm just wondering if there is thought to be any chance of an effective and feasible combo, any conceptions.
  5. Jun 25, 2015 #4
    Despite being an engineer and having an interest in this I have found that the easiest and best approach is reforestation.
    The russian taiga frozen all winter comes alive in the summer and replenishes the earth's oxygen content by 1/3rd !!
    Zero capital.zero maintainance.
    Other than that compounds which absorb CO2 and release them when heated are the most promising.
  6. Jun 26, 2015 #5
    I assume you mean that 1/3 of the oxygen that was depleted over the winter is replenished (a tiny fraction of the atmosphere's total oxygen content).
  7. Jun 26, 2015 #6
    Man I remember that quote verbatim from BBC's Planet Earth. i would assume that they do not lie.
  8. Jun 26, 2015 #7
    The compounds you are referring to are these oceanic phytoplankton type compounds (that capture CO2 then sink and decay at depth to form methane hydrate?) Or is there something else.

    Could super dense "phytophlankton corrals" be used to crank up that cycle - without destroying the chemistry of the ocean?

    Probably this should have been in the "Earth" forum. I didn't even see that forum. Sorry. If the mod wanted to move it?
  9. Jun 26, 2015 #8
    So, you really believe the total oxygen content of the atmosphere is replenished by 1/3??? Please to some research and report back.
  10. Jun 26, 2015 #9
  11. Jun 26, 2015 #10


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    More phytoplankton can mop up more CO2, but the requirement for two critical doses of iron about one week apart limits phytoplankton production.

    There is a natural iron cycle in seawater that involves phytoplankton, which are eaten by krill, that are in turn eaten by whales, that kindly provide the faecal iron on a regular basis. To have more phytoplankton therefore requires proportionally more krill and whales.

    There is a critical tipping point situation here in that higher dissolved CO2 can block the iron cycle. Krill require a low dissolved CO2 in order to form their exoskeleton.
  12. Jun 26, 2015 #11
    Bio engineering is a fascinating idea, but it can't exactly be said to be 'safe', in the sense of being fairly confident of the outcome.
    Reforestation and probably greening of deserts are both possible and safe.
    I am less sure about engineered super-plankton in the sea, but it could work.
  13. Jun 26, 2015 #12

    jim hardy

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    Mother Nature is able to push CO2 down smartly every growing season.

    I assume she uses solar powered photosynthesis.


    I'm downright cynical about sequestration , those huge compressors will be powered by carbon and the process consumes about 10% of a whatever power you're making.

    http://www.kbr.com/Technologies/Process-Technologies/CO2-Compression-and-Sequestration/ [Broken]

    This link might interest you....
    Last edited by a moderator: May 7, 2017
  14. Jun 26, 2015 #13
    I'm talking about scrubbing with amines or metal hydroxides. Though they get degraded really fast. I read somewhere that were trying to create new scrubbers with what else- carbon nanotubes.
  15. Jun 27, 2015 #14
    Haha no I don't believe that. Of course its the regeneration of used O². It is largest forest in the world and does contain almost a 3rd of the world's trees.
  16. Jun 27, 2015 #15


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    It is usually easier to free Mother Nature than to do her job for her.
    Every which growing season? The graph "Recent Monthly Mean CO2 At Mauna Loa" clearly shows an annual cycle.
    I would have expected the CO2 use to be more or less constant with both hemispheres alternating production.
    CO2 seems to rise during the Northern winter while the Southern Ocean is absorbing CO2 during the Southern summer. Why?
  17. Jun 27, 2015 #16
    Yeah that Mauna Loa graph is pretty cool. Haven't seen that before. I would want to make sure and factor out prevailing wind, though I think that's pretty doable in Hawaiii, If I recall. I do remember being struck by just how ridiculously nice the air is in Hawaii. Could have sworn I could smell the O2. :-p. Even if the prevailing wind is part of that graph, still pretty interesting.

    Yeah, huge complicated gas to gas separators on coal power plants, to my thinking just aren't going to happen. I'm prepared to be surprised but just holding your thumb up to that idea, especially the compression and injection process, gives pause. Capital investment up front is just massive.

    I have to admit, I find the phytoplankton idea a bit comforting. Seems like, if things did get desperate enough, that could be a Hail Mary lord help us lever. Not sayin they will, (they either will,or won't) but it's always a good idea to scan the room for exits. Even if you don't know exactly where they go. The catalysis process, iron seeding, seems like something a few big boats could do, with some tough boats to protect them.

    If it was a game of "Risk" and I was Indonesia (at risk of getting drowned), I would be outfitting my navy to do it, if nothing else just to get some leverage on the big CO2 countries.

    At least one link re: risk to pacific island nations.
    http://www.worldbank.org/content/da...AP/Pacific Islands/climate-change-pacific.pdf
    Last edited: Jun 27, 2015
  18. Jun 27, 2015 #17
    I met a guy who was involved with this on the utility side. Very interesting dude. One of those probably-genius types that only ever is filthy dirty. He was working on the pilot, or had. We had lunch in the cafeteria at a different plant (I would love to have seen the project). He could have been any big dirty rigger. Someone had given me the impression he had really been the one to figure out the scale and cost problem in the context of the project. Tarps and ditches was how, not domes and pipes, as I recall. He mentioned how the lab guys were thinking of it as a science project, when really it was a farm. I asked him how well it worked, what removal efficiency was possible. He said something like "whatever you want".


    I had wondered whatever happened
    Last edited: Jun 27, 2015
  19. Jun 27, 2015 #18
    By far, most of the land mass and vegetation is in the northern hemisphere.
  20. Jun 29, 2015 #19
    The New e-gas and e-diesel projects in Germany, use atmospheric CO2.
    It takes like 20 lbs of CO2 to make a single gallon of diesel, so the curve that made
    burning hydrocarbon fuels bad, makes the synthetic version good.
    If we move to making all fuels from scratch, it will not make CO2 go down, it just will not rise much ether.
    The technology kills many theoretical birds.
    Photovoltaic solar power, is great except for it lacked storage, so the energy was not available when needed.
    In addition when we get a large number of solar roof installs, the grid load will become difficult to balance.
    Storing all the surplus electricity as man made hydrocarbons, will store the energy for future use, as well as sequester
    vast amounts of CO2.
  21. Jul 1, 2015 #20


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    If anybody tells an investor, whatever you want, the investor will turn his back and gently walk away.
    The main issue with CO2 sequestration on an industrial scale is the same that green veggies experience. Plants capturing 1 mole of CO2 require around 120 moles of water or worse (google the transpiration ratio). There is very little CO2 in the atmosphere compared to the other gases (400ppm or 1 in 2500). Any chemical or physical process of CO2/air separation will be strongly hampered by this low yield condition.
    The ideea of fuel from CO2 is nice and rather old, yet impractical to say the least.
  22. Jul 1, 2015 #21
    The reality is the cost of finding and extracting oil from the ground will continue to rise.
    However impractical, hydrocarbons offer the best long term energy storage currently available.
    They are now saying the process is 70% efficient, so it would take about 55 Kwh of electricity
    to make a gallon of diesel.
    While there could be other sources of carbon, for making hydrocarbons (the Navy extracts CO2 from sea water),
    part of this is political. Atmospheric CO2 extraction for making fuel would provide the fuel necessary
    for our modern lifestyles, while also satisfying the issue of CO2 emissions.
    In addition the solution is compatible with all of our existing distribution infrastructure.
  23. Jul 1, 2015 #22
    I'd be a little surprised if Audi hadn't done their basic homework before investing in developing the process. Though I can imagine that they are assuming huge uncertainty across a number of dimensions. This whole idea of using it as a storage mechanism for wasted off-peak wind etc, seems solid to me.

    No doubt water is a big constraint. Luckily the planet still has a lot.
    Which brings up the subject of desalination technology, and how key it may be to the cost and feasibility problem in other domains, and whether or not there may be breakout opportunities in the physics there. Topic for another thread.

    To which cross-domain systems mapping seems really important to me. Since none of the worlds problem are really isolated from all the other problems, and the whole darn thing gets almost totally empirical at that scale, and at that level of integration, given uncertainty.
  24. Jul 1, 2015 #23


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    There is no need to take the CO2 from the air. CO2 is available concentrated (with water) in the exhaust of many devices that consume fuel.
    It makes no difference to atmospheric CO2 concentration if the CO2 is taken from the atmosphere or taken from a process with higher concentration that would otherwise release it to the atmosphere.
  25. Jul 1, 2015 #24
    I had originally been thinking of the problem of removing it from the atmosphere. But I guess it's more correct to picture it as a cyclic system, in which there is not a static atmosphere. And as you say, it makes the most sense in terms of total carbon-cycle leverage to capture/remove it from the points of highest leverage (highest concentration being probably the biggest factor in that leverage). If rates of release are reduced through source-centric strategies of capture, natural sequestration processes do provide a counter weight capable of reversing total atmospheric concentration.

    I think the question that led me to wonder is, what if those natural counter-processes are insufficient to support our choices, or lack thereof, w/respect to carbon release?

    I guess the cool thing about Audi's proposal is that it could create a market driver for capture - and money makes the herd do stuff.

    That said there could be a situation where the sources are not under the control of decision makers or effective markets...kinda sorta like it is now.
    Last edited: Jul 1, 2015
  26. Jul 1, 2015 #25
    Audi picked this up from work started at Fraunhofer University.
    The idea started as a way to store Germany's vast summer photovoltaic surplus, for winter heating.
    The idea of e-gas storage is not viable currently, due to the low price of natural gas,
    I thought using the national natural gas grid as storage was cool idea.
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