Carbon Dioxide Capture and Sequestration

8/11/2019 Carbon Dioxide Capture and Sequestration

1/12

Averting Doomsday: A Pessimist's Outlook on Future Demand for Direct Air Carbon Capture

Alexander RobertsonSpring 2014

It is definitively clear that humanity must reduce or counteract its current rate of carbon dioxideemissions in order to prevent atmospheric CO 2 from reaching toxic levels, to avoid the acidification ofEarth's oceans, and to slow worldwide climate change. While we have made encouraging progress indeveloping and implementing renewable energy systems, begun to embrace the advent of electricvehicles, and initiated efforts to develop cleaner power plants, I remain overtly skeptical in regards to ourcollective willingness and ability to slow CO 2 emissions at a pace rapid enough to avoid critical climatechange thresholds be it 450 ppm CO 2, a 2 C temperature increase, or otherwise. As such, a certainamount of direct air carbon capture and storage will be imperative if catastrophic, perpetually escalating

impacts on humanity and the global biome are to be avoided, by either finding ways to never surpassdesignated hazardous boundaries or to recover from an overshoot past them. Though this inevitability has become increasingly acknowledged over the last twenty years, the parameters of the task awaiting us exactly how much DAC might be required and how many DAC systems might have to be manufacturedand put into use remain relatively uncharacterized.

Split into a three-part dialogue addressing 1) the range of emissions scenarios discussed in the literatureand their environmental implications; 2) the state of DAC technology under development; and 3) thescope of future DAC necessary to achieve particular atmospheric benchmarks, this paper aims to outlinethe goals we should be establishing for integration of DAC into humanity's framework ofenvironmentally-minded undertakings. By adopting a pessimistic outlook on society's capacity forlimiting year-by-year emissions increases my stance is that total annual emissions will not fall belowtoday's level within twenty years and continue to rise for at least that long, with high-carbon centralizedsources persisting for most of the 21 st century and treating DAC as an essentiality rather than a last-resort safety valve, the discussion herein amounts to a depiction of the DAC challenge, both in terms ofthe CO 2 tonnage we must extricate and the amount of DAC systems we should produce over time.

Outlook on Future Societal and Power Plant Emissions

Before delving into air capture itself, let's examine the atmospheric context in which it will be deployed.For our purposes we will consider only carbon dioxide, as it is currently the predominant climate player

amongst the greenhouse gases and its capture from air has been more extensively studied than CH 4 and N2O (it should be noted, however, that these cycling of these three gases is interrelated in ways that we donot yet fully understand and that further unimpeded increases in atmospheric CO 2 concentrations maylead to unanticipated consequences involving methane, nitrogen, and the ecological processes involvingeach). 1 First, the utmost basics: since the dawn of the Industrial Era, the juncture beyond which we canconsider anthropogenic emissions to be significant and can generate reliable data characterizing emissionsources, approximately 2100 gigatonnes of CO 2 have been introduced into the environment due to fossil


2/12

fuel combustion and land use disruptions. 1 During this time atmospheric carbon CO 2 dioxideconcentrations leapt from 278 parts per million to over 400 ppm today. 1,10 An increase of this magnitudein such a short time span is unprecedented over at least the past 22,000 years (and likely much, muchlonger we simply lack avenues of collecting rigorous data further back in Earth's existence); projections

by the International Panel on Climate Change (IPCC) indicate further ppm increases in coming decades,

as can be seen in Figure 1.1

Figure 1: Depiction of past ppm increases and IPCC projection ranges for future levels.

Why is it urgent for us to combat the increasing prevalence of carbon, and what concrete environmentalimpacts are associated with continued emissions increases or even with theoretical immediate cessation?CO 2's post-emission pathways result in the carbon problem manifesting itself by air, by land, and by sea.Proportionally speaking, about half of CO 2 released into the atmosphere is absorbed by aqueous andterrestrial sinks within a century (however, increasing saturation of these sinks causes their temporal CO 2 uptake capacity to shrink), while the remainder persists in the air for thousands of years. 11 What are the

broad strokes of the environmental response to elevated carbon content on these three fronts? Airtemperatures rise with radiative forcing intensity, causing glacier melt, heightened erosion rates, a greaterlikelihood of forest fires, and dramatic seasonal fluctuations. Atmospheric oxygen levels fall as CO 2 concentrations surge. Sea levels rise, ice caps melt away, ocean pH levels drop, and overall marinetemperatures increase while oxygen content declines posing risks to CaCO 3-dependent bottom-dwellers,their counterparts moving about the water column, and ubiquitous primary producers. Extreme weatherevents occur with greater frequency, putting both human lives and our energy infrastructure in danger. 2,3


3/12

At this point, the presence of severe ongoing environmental shifts, and humanity's direct role in inducingthem, is beyond dispute. Furthermore, because CO 2 persists in the dynamic carbon cycle on the order ofmillenia before permanently binding to various minerals, and because there exists a lengthy lag phase

between when a ppm level is reached and the time its atmospheric, oceanic, and terrestrial ramificationsare fully realized, we are effectively locked in to further intensifying of these climatic and environmental

transformations even if today were to be the last day CO 2 molecules are ever released into theatmosphere. 2 Exacerbating this actuality is what Dr. Klaus Lackner refers to as "the black swan problem":there could very well be unforeseen future consequences that acutely intensify the magnitude of overallenvironmental harm. The uncharted waters embodied by permafrost and methane hydrate decay is anexample of this: for all our software models and projections and postulations, we simply do not knowwith any certainty how these circumstances will play out. Though the black swan line of thinking couldalso swing in the opposite direction, towards the notion that Earth will compensate for our misdeeds andstabilize itself without any assistance, this would be an attitude of complacency and cowardice, and likelyresult in future generations ending up in a hole deeper than the one we have already dug for ourselves.

In order for a < 2 C rise beyond 1861-1880 temperatures to be attainable, the post-1880 global emissions budget is roughly 3670 Gt CO 2, and likely less than that after considering probabilistic ranges and peripheral greenhouse gas factors. We are already more than half of the way to this limit, and emissionscontinue to rise at an annual rate of 1-2%. 2 Considering new and probable upcoming policy changes, weappear to be heading for a 3.6-5.3 C increase over pre-1750 conditions. 5 The next international summiton climate change is scheduled for 2015, but its agreements on emissions policies will not become

binding until 2020. 5 The trend of annual CO 2 output increases is likely to continue until at least that time.Strides being made by OECD countries in reducing coal-sourced emissions and boosting renewableenergy production are nullified by developing nations' escalating coal usage and ever-growingtransportation sector; this keeps us is in line with the newly direct relationship between CO 2 and globalGDP over the last ten years. 5 In 2013 the IEA presented its 4-for-2C proposal, which outlines four steps

that could at least keep us within striking distance of the 450 ppm scenario by the time new internationalmeasures take effect in 2020. While it is encouraging that we theoretically could adopt these changes andapproach the 450 ppm path, I will not be holding my breath despite the attraction of long-term economic

benefits that supposedly accompany the environmental relief. The proposal relies on energy efficiencychanges for half of its averted emissions relying on businesses, homeowners, and individuals to takeunprecedented broad autonomous action and on coal-fired power plant cutbacks for another improbable21%.

As Dr. Klaus Lackner discusses in his Carbon Sequestration course at Columbia University, there is asimple reason that fossil fuels constitute a quality energy source and that humans have become whollydependent upon them. The reason? Hydrocarbons are more energy-dense than just about anything else.An example: over 40 MJ of energy may be drawn from a single kilogram of jet fuel, while our mostadvanced batteries contain a relatively meager .5 MJ/kg. This fact (in tandem with research showing that,in spite of our sincerest efforts to suck the earth dry, there remain massive coal, oil, and natural gasreserves, containing thousands of gigatonnes of CO 2, for the tapping) suggests that there will continue to

be a set of systems and machinery shipping freighters, naval ships, commercial airplanes, fighter jets,high-performance automobiles, and more whose demand for hydrocarbons will not dissipate over time,simply because hydrocarbons are and will continue to be the only fuel source capable of providing


4/12

adequate power within given spatial constraints. Carbon tax and cap-and-trade possibilities, along withthe prospect of clean synthetic liquid fuels, are beyond the scope of this paper, but it is an inevitabilitythat for as long as there are customers willing to pay for such hydrocarbon-derived energy and the cost ofextracting and processing it remains manageable, enterprising groups will continue to line up to derive

profit from fossil fuel usage. A certain amount of emissions by the aforementioned transport and other

decentralized sources are likely to continue indefinitely if direct air capture is ever to be the leadingforce in a net-negative emissions scenario, it will first have to neutralize this output before going to workon extant CO 2.

7

Green energy has made notable strides over the past couple decades but also seems to have bred a certainlevel of false confidence in our capacity for attaining a global society whose electrical and fuel demandsare met by sustainable energy alone. While solar, hydrothermal, and wind energy systems now generateapproximately 20% of our electricity, total anthropogenic emissions are still ascending. According to theIEA's New Policies Scenario, global electricity usage could increase by over two-thirds between 2011 and2035, with renewable sources by then providing over 30%. This would be a step in the right direction, andas of now total renewable energy production is swelling at a pace in line with what is demanded by 2 Ctemperature rise scenarios. The catch is that in the grand scheme of things, renewables are still early on intheir development and this rate of growth is likely to prove unsustainable in the long term. 5

Pre-combustion capture and flue gas scrubbing, the cousins of direct air capture and themselves animportant tool for battling climate change, are central to potential future reductions in power plantemissions. The energy sector currently generates two-thirds of global greenhouse emissions. A graphical

breakdown of emission sources is shown in Figure 2. With total energy demand growth projected tooutpace concurrent growth in renewable electricity production, an expanded flue gas CCS program, intandem with a continued shift to natural gas and renewable energy, will be integral to reducing emissionsto a level where implementing DAC is sensible. Non-DAC CCS ventures, which encompass carbon

capture in both power generation and industrial settings, are on the rise but not yet proliferating at a ratesufficient to meet the expectations of scenarios on the optimistic end of the IPCC and IEA spectra. 2Cconditions call for annual capture and storage capacity to reach 260 Mt CO 2 within the next fifteen years,while we are currently on track for only 65 Mt/year in 2020. 5


5/12

Figure 2: Breakdown of fossil fuel CO 2 emissions by usage category.

Though CO 2 is much less concentrated in ambient air than in flue gas and other industrial output streams,thermodynamic analyses suggest that, at a certain threshold, extraction of CO 2 from the atmosphere is notconsiderably more energy-intensive after taking into account the high release temperature and sulfurcontent of waste gasses. For flue gas, the upper bound of this regime occurs at 80-90% CO 2 removal.Beyond this point, it makes more sense to assign that last 10-20% to DAC. So, even if maximallyeffective scrubbers are applied to power plants worldwide, there will continue to be a much-reduced butsteady flow of emissions from the energy sector that will be within DAC's domain for as long as thecarbon cycle remains open and fossil fuel-consuming power plants remain in use. 11

Considering the insufficient pace at which we are progressing with a range of CO 2 emissions reductionapproaches from renewable energy to power plant CCS to policy changes to infrastructure and lifestyletransitions and recognizing a 1% population growth rate, dozens of terawatts in probable future energydemand, and increasing emission rates in developing nations, we appear destined to obliterate the 110tonne per (already alive) person CO 2 allowance that would allow for 450 ppm to remain an attainabletarget. 7

Direct Air Capture: Today's Status & Tomorrows Possibilities

In-depth attention to the climate change issue, with less of the longstanding fascination over the semanticsof the "global warming" concept, seems to be on the rise articles discussing the dire state of theatmospheric carbon problem have recently been printed in high-profile publications like the New YorkTimes and the Guardian, and on May 6 the White House released its 2014 National Climate Assessment,which contains some of the strongest environmental stances (in language at least, if not tangible policychanges) yet taken by the US federal government. Despite this swelling sense of urgency, awareness ofthe current state of DACCS technology, and of its likely crucial role in alleviating the environmentalimpact of fossil fuel emissions, remains bafflingly scarce. Representative of this is the complete absence


6/12

of DAC, along with only a passing mention of flue gas CCS treatment, in the National ClimateAssessment's Responses section. It is somewhat logical that a White House-sourced report would befocused more on political and societal outlooks than on the technological landscape, but this also maysuggest that we continue to lag years behind the carbon problem in terms of realistically assessing itsmagnitude and the need to prepare aggressive solutions. Direct air capture is the only theoretical CO 2 sink

that can be fully separated from all sources, and it would also not be burdened by renewable energysystems' dependence on location and temporality.

While a greater prevalence of government-mandated carbon credits and research funding would helpspeed the development and deployment of DAC systems, there are other avenues by which the upfronteconomic burden of DAC can be alleviated. Concentrated CO 2 streams have significant value in bothenhanced oil recovery and greenhouse contexts. Greenhouse growers seeking to improve vegetationyields and oil companies hoping to wring out their oil fields are willing to pay between $100 and $300 perton CO 2.7 Implementing DAC for EOR and greenhouse purposes may help speed research, development,and learning-by-doing progress during these fledgling years. Additionally, enhanced oil recovery'sdemonstration of affordable CO 2 transport and injection is of relevance to the prospect of future large-scale geological storage, though long-term monitoring of such stores has not yet been sufficiently carriedout. For sequestration by terrestrial injection to be a viable storage method, it must eventually be shown to

permanently confine a high percentage of injected CO 2.

Though researchers have made notable strides in the development of direct air carbon capturetechnologies, there still persists a wide gap when it comes down to perspectives on the maximalefficiency and minimal costs of future capture systems. A number of elements must be considered whenevaluating overall system efficiency: the input energy consumed during the capture, release, compression,and transport of CO 2; the physical size of a device relative to its capture volume potential per unit time;the repeatability of its chemical reaction pathways; and the feasibility of manufacture and installation.

As it stands today, it is clear that the numerous avenues of CO 2 emission avoidance represent atmosphere-relief options that are both more economically affordable and easier to implement than direct air capture.As phrased by Dr. Lackner, to roll out DAC as an emissions combatant at this point would be akin totrying to steer an aircraft carrier with a tiny wooden rudder. For DAC deployment to be logical, its $/tCO 2 capture cost should be less than $/tCO 2 aversion alternatives. Since even the most optimistic currentestimates of DAC costs are higher than all but the most laborious aversion tactics, this reasoning impliesthat large-scale DAC will only become efficacious after emissions from power plants, transport, andindustry have been reduced to a tiny fraction of today's output through a combination of flue gasscrubbing, energy efficiency adaptations, increased renewable energy production, and other greenefforts. 4

That being said, DAC technology should not be abandoned until the possibility of near-zero emissions iswithin striking distance. Instead, we should continue to cultivate clean energy systems and pursue everyavailable emissions-reduction strategy while simultaneously committing serious research work tooptimizing DAC. The longer we delay in doing so, the farther into the 21st century we push theconvergence of CO 2 aversion and CO 2 capture costs. The American Physical Society (APS) issued adirect air capture technology assessment in 2011 which identified the achievable cost of DAC using


7/12

demonstrated approaches to be between $610 and $780 per ton of CO 2 captured, not including post-capture transport and storage. Serving as the model for this assessment was a sodium- and calcium-dependent countercurrent flow system that used fans to drive ambient air over the absorption surface. Inthis case, captured CO 2 was released by heating CaCO 3 at a thermodynamic cost of 179 kJ/mole. 11 If thistechnology were indeed our most auspicious option, and its predicted costs are accurate, then DAC would

be rendered indefinitely impractical.

Dr. Lackner compares the referenced APS analysis to an attempt at determining whether birds can fly bystudying a penguin. The NaOH-based capture process examined by APS illustrates perhaps the mostcritical factor in designing a DAC process: the binding agent must be able to securely extract highlydiffuse CO 2 from air and then, more importantly, release it at a specified time without a prohibitiveenergy input, with energy expenditures also curtailed at every possible juncture throughout the system sothat net CO 2 uptake is maximized. The APS system did a terrible job of managing energy in these ways.A device designed by Dr. Lackner instead utilizes amine tethering of CO 2 by adsorbence and achievessubsequent freeing of captured gas through a moisture swing CO2 is picked up in dry air by resin-coatedsurfaces, with a very low requisite flow rate, and released upon exposure to humidity. By eliminating theneed for constant fan activity and high-temperature release conditions without sacrificing low-concentration CO 2 extraction capacity, this approach represents a sizable efficiency improvement over theAPS benchmark system. Incorporation of this technology into a device approximately the size of astandard shipping container could pull a tonne per day of CO 2 from the atmosphere at a cost $100/tCO 2.David Keith believes a comparable cost could be achieved with his sodium hydroxide process, whichdiffers significantly from APS's in materials and sequencing. 6,7,8,9

With further research, development, and testing in the coming years, we will be able to boost devices'capture potential and lower their per-tonne costs while both optimizing the most promising contemporaryDAC technologies and experimenting with novel materials and mechanisms that could revolutionize the

next generation of DAC. Nano-patterned panels that maximize contactable surface area and metal organicframeworks may help generate substantial DAC progress, and it is probable that DAC R&D will lead toflue gas scrubbing advances as well.

Multivariate Models for Direct Air Capture Scaling

So, how much CO 2 might we need to capture directly from the atmosphere, how many DAC systemsshould we imagine manufacturing and operating, and what could the sequence of implementation looklike? The answers to these queries hinge on the extent of future global CO 2 emissions, the atmosphericCO 2 level we deem to be ideal, the raw capture potential of each DAC unit, and the timeframe within

which we hope to reach our benchmarks.

Constituting the DAC projection framework will be a set of simplifying assumptions and objectives:

1) A conservative performance improvement in DAC technology, by 2035, to 2.5 tons of CO 2 per day isused as the baseline extraction rate for a single shipping container-sized DAC unit, with intermediate andextreme future values of 10 and 25 tCO 2/day also addressed.


8/12


9/12

Figure 3: Summary of modeling emissions values and corresponding total DAC needed. All quantities given in gigatonnes CO 2.

Scenario Emissions2014-2100

Emissions2100-2200

Emissions1750-2200

ppm in 2200w/o DAC

DAC for450 ppm

DAC for350 ppm

DAC for280 ppm

A 1708.75 284.8 4030.5 440.4 -140.9 1327.1 2354.7

B 3130.75 521.8 5689.5 515.5 962.2 2430.2 3457.8C 4552.75 758.8 7348.5 589.7 2050.6 3518.6 4546.2D 5634.75 939.1 8610.9 734.0 4168.7 5636.7 6664.3E 8141.75 1357.0 11535.9 1028.4 8491.4 9959.4 10987.0

DAC and Carbon Cycle Dynamics: To account for equilibration between atmosphere, ocean, and land,it is assumed that 7.34 Gt CO 2 equates to 1 ppm and that 2 ppm of capture leads to a true atmosphericreduction of 1 ppm. Thus, 14.68 Gt CO 2 must be captured and stored to generate a 1 ppm decline.Because biomass CCS is much more space-intensive than DAC, and because it is plausible that availableland will be primarily dedicated to facilitating increased agricultural output in the face of populationgrowth, DAC by manmade machinery is treated as the sole atmospheric capture sink.

Figure 4: Total DAC needed by DAC under varying emissions scenarios and ppm objectives.

Discussion and Conclusion: In order to provide a measure of the DAC machinery requirements implied by each CO 2 capture goal, the complete set of gigatonne- defined values were translated into unit -year s.One unit-year is equivalent to the annual CO 2 uptake of an individual DAC system operating at 2.5, 10, or25 tCO 2/day. To draw the atmosphere back down to 450 ppm from RCP8.5-derived Scenario E wouldnecessitate over 9.3 billion unit-years by 2200 with systems averaging 2.5 tonnes of daily CO 2 capture. Ata system lifetime of 12 years, this would require upwards of 775.4 million total units produced between

280 ppm

350 ppm

450 ppm


10/12

2035 and 2190. Comparatively, achieving 450 ppm under Scenario B necessitates slightly more than 1 billion unit-years and 87.9 million total units produced during our 165-year capture window certainly afeasible task given our ability to roll over 80 million motor vehicles out of factories each year. If futureDAC advances enable 25 tCO 2/day capture rates, then even the drastic emissions condition of Scenario E

becomes manageable at 930.6 million unit-years and 77.5 total units. Meanwhile, Scenarios B, C, and D

would become a relative walk in the park at 8.8, 18.7, and 38.1 million units, respectively. I anticipatehumanity heading somewhere between Scenarios C and D, but with the conceivable development of 10tonne/day capabilities we would be well-equipped to recover: 46.8 to 95.2 million DAC units could pullthe atmosphere back to 450 ppm. If 350 ppm the threshold I would like to see us return to is insteadthe target, 96.4 to 154.4 million 10 tonne/day units are in order.

Figure 5: DAC unit-years needed to attain 450, 350, or 280 ppm in each emissions scenario with differing average capture rates by individual units .

Target: 450ppm in 2200

Unit-Years @2.5 tCO2/day

Total Units Unit-Years @10 tCO2/day

Total Units Unit-Years @25 tCO2/day

Total Units

A 0 0 0 0 0 0B 1054.5 87.9 263.6 21.2 105.4 8.8C 2247.3 187.3 561.8 46.8 224.7 18.7D 4568.5 380.7 1142.1 95.2 456.8 38.1E 9305.7 775.5 2326.4 193.8 930.6 77.5Figure 6: Unit-years and total DAC units to reach 450 ppm by 2200 at different capture rates. Values in

millions. Scenario A requires zero DAC because 450 ppm has not been surpassed in 2200.

These results show that with further improvements in technological efficiency and reductions in per-tonnecosts, DAC would serve as a potent tool in solving the atmospheric carbon problem. The extent of scaling

necessary to counteract anthropogenic emissions and either keep CO 2 below 450 ppm or induce a returnto 350 or 280 ppm is decidedly within our mass manufacturing capabilities, especially if we are able to

boost the capture rates of shipping container-sized devices to 2.5 tCO 2/day or higher. Economicconstraints, lack of governmental support, and logical prioritization of other green initiatives will keeplarge-scale DAC on the backburner in coming years, but the unit-year and total unit demands calculatedhere demonstrate that the urgent fortifying of ongoing R&D efforts could put us in a position to takeenvironmental destiny into our own hands by the end of the 23 rd century.


11/12

References

1) Ciais, P., C. Sabine, G. Bala, L. Bopp, V. Brovkin, J. Canadell, A. Chhabra, R. DeFries, J. Galloway,M. Heimann, C. Jones, C. Le Qur, R.B. Myneni, S. Piao and P. Thornton, 2013: Carbon and OtherBiogeochemical Cycles. In: Climate Change 2013: The Physical Science Basis. Contribution ofWorking Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change[Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V.Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and NewYork, NY, USA.

2) Collins, M., R. Knutti, J. Arblaster, J.-L. Dufresne, T. Fichefet, P. Friedlingstein, X. Gao, W.J.Gutowski, T. Johns, G. Krinner, M. Shongwe, C. Tebaldi, A.J. Weaver and M. Wehner, 2013: Long-term Climate Change: Projections, Commitments and Irreversibility. In: Climate Change 2013: ThePhysical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of theIntergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K.Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge UniversityPress, Cambridge, United Kingdom and New York, NY, USA.

3) Cubasch, U., D. Wuebbles, D. Chen, M.C. Facchini, D. Frame, N. Mahowald, and J.-G. Winther,2013: Introduction. In: Climate Change 2013: The Physical Science Basis. Contribution of WorkingGroup I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker,T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex andP.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York,

NY, USA.

4) IPCC (2005). IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by WorkingGroup III of the Intergovernmental Panel on Climate Change [Metz, B., O. Davidson, H. C. deConinck, M. Loos, and L. A. Meyer (eds.)]. Cambridge University Press, Cambridge, UnitedKingdom and New York, NY, USA, 442 pp.

5) International Energy Agency Redrawing the Energy-Climate Map. World Energy Outlook SpecialReport. International Energy Agency, Paris, France (2013).

6) Keith, D., M. Ha-Duong, & J. Stolaroff (2005). Climate Strategy with CO2 Capture from the Air. Climatic Change, 74(1-3): 17-45 doi:10.1007/s10584-005-9026-x .

7) Lackner, Klaus. Carbon Sequestration Lecture Slides. Columbia University 2014. New York, NY,USA.

8) Lackner, K.S. (2010). "Washing Carbon out of the Air." Scientific American , June 1, 2010.

9) Lackner, K.S. Capture of Carbon Dioxide from Ambient Air. Eur. Phys. J. Special Topics,176(1):93-106.

10) co2now.org

11) Archer et al. Atmospheric Lifetime of Fossil Fuel Carbon Dioxide. Annu. Rev. Earth Planet. Sci.37:117-34. 2009.
http://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdfhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://dx.doi.org/10.1140/epjst/e2009-01150-3http://www.scientificamerican.com/article.cfm?id=washing-carbon-out-of-the-airhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://dx.doi.org/10.1007/s10584-005-9026-xhttp://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdf


12/12

12) APS (2011). Direct Air Capture of CO2 with Chemicals.

Carbon Dioxide Capture and Sequestration

Documents

Transcript of Carbon Dioxide Capture and Sequestration