Direct Capture of Carbon Dioxide From the Air.

The practice described in the title of this diary will, I predict, never happen, although, as I will describe below relying on a paper published in the scientific journal Industrial and Chemical Engineering Research - there are many other such papers including those of the great and highly principled Chemistry Nobel Laureate George Olah, who being a scientist rather than a movie (or rock) star was essentially ignored by the public - it may be technically feasible to do this or to have done it.    

But it will not happen.   The fight against climate change and its attendant disaster, as the events in the American grain belt (and in the last few years in other grain belts around the world) demonstrate so dramatically, is over, so much over that even our even insipid media is beginning to get it.  

In 2012, human beings will burn more dangerous oil, more dangerous coal and more dangerous natural gas than ever before.   The waste from this burning will be dumped directly into the planetary atmosphere where it will serve to help kill 3.3 million people per year - half under the age of five - through direct health effects, and many, many, many more ultimately from climate effects, probably including, in short order, famine not to mention, just plain heat.

They should have died hereafter.   There would have been time for such a word.

When I go outside these days - something I try not to do since it's so damn hot out there - I cannot help seeing the dead and dying trees.    Some years back, after a hiatus during a period of mutual distain between the management of this site and myself, I returned here to write a diary about the death of trees from heat and drought in the area where I live, New Jersey, citing a paper from the journal Tree Physiology.   Nitrogen, Climate Change, Drought, and Tree Physiology.  I wrote:

We're having a terrible drought - coupled with outbreaks of extreme temperatures - here in Western New Jersey, and it seems to be killing some very old and very beautiful trees.   It's very sad.

The dying is still going on.   I said then that I would spend more time reading that journal, Tree Physiology, but I really haven't, although I downloaded a bunch of papers a week or so ago.    But I didn't read them.   If I did, I would most likely break down weeping.   There's - how ironic is this - a bumper sticker one sees at times that reads "Trees are the answer."   No they're not.   They're going to end up dead, burned or rotted.   They are no answer.   They're just another set of victims.

The paper from the primary scientific literature I will discuss in this diary comes from a recent issue of the journal listed above (Ind. Eng. Chem. Res. 2012, 51, 8631−8645).   It is entitled "Analysis of Equilibrium-Based TSA Processes for Direct Capture of CO₂ from Air."

It's about what might have been, not what is, not what will be.

Excerpts below:

"TSA" stands for "Temperature Swing Absorption" and is related to practice of "Pressure Swing Absorption."   Both processes can be used to separate components from air and from other mixtures of gases.   Both require energy, which is being consumed in ever greater amounts already, and as stated above, with more coming from dangerous fossil fuels than ever before.

The article begins with a mistake that derives from using an old citation, but the real mistake is not the outdated fact stated in the paper, but that too large a portion of humanity would rather read about the fate of the football program at Penn State than the fate of the planetary atmosphere.

Football.   The planetary atmosphere is a political and moral football.

Here's the introduction from the paper, containing the mistake:

The growing levels of CO₂ in the atmosphere and their possible detrimental effect on the global climate have made carbon management technologies one of the most widely researched areas of recent times. The current CO₂ level in the atmosphere is 379 ppm.1 One benchmark technology for reducing CO₂emissions is using aqueous solutions of amines to capture CO₂from post combustion flue gas. Other strategies available for capture of CO₂ from flue gas using absorption and adsorption have recently been reviewed.2 Point sources like large coal-fired power plants typically account only for about one-third of the anthropogenic CO₂ released to the atmosphere.3 Much of the remaining two-thirds is due to transportation, small power plants, and chemical industries. Under the plausible assumption that fossil fuels are going to continue to be the predominant source of global energy in the near future, no commercial carbon capture technology currently exists that can be used to offset CO₂emissions from this two-thirds of total emissions. If deep reductions in global CO₂ emissions are to be achieved, a broad range of technology and policy options need to be explored.

The error, of course, is the figure "379 ppm."

Reference 1 cited, is the IPCC report from 2007.   Don't blink.  You'll get it wrong.    The actual figure for "current level" - this at the top of a high mountain, where the Maxwell-Boltzmann distribution actually dilutes heavy gases like carbon dioxide is found at the website of the Mauna Loa Carbon Dioxide Observatory.   The "current" figure, as of this writing is 395.77 ppm.

Small mistake.   Don't worry.   Be happy.

Football!

More from the paper:

Direct capture of CO₂ from air, which we will refer to below as air capture, is one technology that has the potential for capturing CO₂ emissions from all possible sources. Air capture aims to make use of the concepts and technologies developed for CO₂capture from flue gas capture and apply them to capture CO₂from ultradilute concentrations in air. The concentration of CO₂is ∼250 times less in air than in flue gas. The theoretical minimum energy required for air capture, however, is only 3.4times that for flue gas capture.4 There has been far less work performed on air capture than on flue gas capture, but the Direct capture of CO₂ from air, which we will refer to below as air capture, is one technology that has the potential for capturing CO₂ emissions from all possible sources. Air capture aims to make use of the concepts and technologies developed for CO₂capture from flue gas capture and apply them to capture CO₂from ultradilute concentrations in air. The concentration of CO₂is ∼250 times less in air than in flue gas. The theoretical minimum energy required for air capture, however, is only 3.4times that for flue gas capture.4 There has been far less work performed on air capture than on flue gas capture, but the economic and technical feasibility of air capture has been intensely debated.5−7 Jones has recently reviewed the development to date of air capture technologies.3

Reference 3, by "Jones" is

Jones, C. W. CO2 Capture from Dilute Gases as a Component ofModern Global Carbon Management. Annu. Rev. Chem. Biomol. Eng.2011, 2 (1), 31−52.

I haven't picked that paper up.   I should.  It should be good for a laugh.

The paper discusses some early computations about the cost of capturing carbon dioxide from air, including metal hydroxides precipitated by calcium and calcining the resultant calcium carbonate to regenerate lime.

It was reputed to cost $600/ton to recover carbon dioxide.

A recent report on the feasibility of air capture by the AmericanPhysical Society (APS) focused exclusively on this sodiumhydroxide based process, and estimated the cost of using thistechnology to be close to $600/t CO₂.7

According to the EPA, for reference, a gallon (3.79 liters) of gasoline releases about 8.93 kg of the dangerous fossil fuel waste CO₂.   The same link herein suggests that the average American dumps, from his car, 5.1 metric tons of said waste from his or her car each year.   This means that the metal oxide approach would require an investment of each average American of $3,000 bucks a year, roughly, just for his or her (or its) car, never mind all the coal that is burned for things like running the computers of anti-nukes so they can remind us that everyone in Japan died from Fukushima and that everyone in San Diego died from eating radioactive tuna fish created by Fukushima.

Really.

The authors of the paper hope some cheaper means can be found than metal oxides - and I'll be up front here and state that I am rather fond of metal oxide mediated carbon capture for reasons about which you couldn't care less - and they discuss a variety of silica based absorbents, if I recall correctly the too much ignoredold genius George Olah has also discussed this class.

They're probably pretty damn good.

For the thermodynamic and economic calculations in the paper, the authors refer to a particular silica based absorbent, TRIPE-MCM-41.

Tripe.   I swear.  Tripe.

Which is what the hope that humanity will avoid climate catastrophe is.

In one process ("Process B" and there's a lot of processes discussed in the paper) the energy cost of recovering carbon dioxide is given as 6328 MJ/t CO₂.

Last year, humanity dumped about 31.6 billion tons of the dangerous fossil fuel waste CO₂ into its favorite waste dump, the planetary atmosphere.

If one has not joined Greenpeace and thus can still multiply, divide, add and subtract, one can directly calculate that to recapture the pre-sequestered and then de-sequestered carbon from Earth's atmosphere, it would require 199 exajoules of energy using process B.

We're saved.

This is about twice the annual amount of energy consumed by the United States, that "environmental" country that we live in.   Humanity as a whole is now consuming about 520 exajoules of energy as a whole.

Don't worry.   Be happy.

All of Europe, after throwing hundreds of billions of Euros down the rabbit hole, now produces about 2 exajoules of so called "renewable energy."

We're saved.

Actually, we do know how to produce energy without carbon dioxide on a large scale, but a rather large portion of the population, motivate by fear, ignorance and superstition rather hates this form of energy, because it could be responsible (ultimately, albeit not this far) for a few deaths here and there after a 9.0 earthquake and a 15 meter tsunami.

As we all know, everything else, including buildings and cars is otherwise completely safe in a 9.0 earthquake and 15 meter tsunami.

I could go on and on with the cool stuff in this paper, but let me just run the conclusion by you.

The authors, very nice guys I'm sure, and very smart guys conclude like this:

In conclusion, we have developed process models that account for some of the issues that need to be taken into account while considering the viability of adsorption-based air capture technologies. We have identified one process that appears promising based on these initial models. Our work should motivate future experimental and modeling efforts to refine the specifications of processes like this one and define more detailed estimates of their economics.

Don't worry guys.   We, humanity, will get right on it, right after we figure where the grain is going to come from.

Enjoy your evening in spite of any heat or other extreme weather warnings may apply in your area.