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CO2 Capture Project
CO2 Capture Project
project resultsCo-operating for a better environment
CO2 Capture Project
The CO2 Capture Project (CCP) is a partnership of
government and industry that is supporting research to
advance the scientific and technical basis for the capture
and geological storage of CO2.This will provide a new
set of options for reducing CO2 emissions that can
complement improved energy efficiency and increased
use of non-fossil energy resources.
Sponsors of the CO2 Capture Project:
Government
European UnionUS Department of EnergyNorwegian Research Council KLIMATEK Programme
Industry
BPChevronTexacoEnCanaENINorsk Hydro ASAShellStatoilSuncor Energy Inc.
Co-operating for a better environment www.co2captureproject.org
Contents
Introduction
1 Introduction
2 Climate Change
3 General Overview - CO2 Capture & Storage
4 The CO2 Capture Project
CO2 Capture
5 General Overview
6-8 Project Results
CO2 Storage
9-10 General Overview
11-12 Project Results
Conclusion and Next Steps
13 Project Conclusion
13 Next Steps
14-15 List of research programmes
16 Acknowledgments
IntroductionThe prospect of climate change is a matterof deep public concern.There is an increasingconsensus that appropriate action to mitigateclimate change will mean stabilising theconcentration of CO2 in the Earth’satmosphere.There are many technologyoptions that can help, but it is clear that allmay add additional cost to the price we payfor energy.
Given the scale of the climate challenge andthe need to provide affordable energy in manydifferent cultural, social and operationalsettings, a portfolio of approaches will berequired.The solution will not be the same inevery setting. One option that has broadpotential application is the technology of CO2
capture and geological storage. Capturing andstoring the CO2 from the combustion of coal,oil and natural gas could deliver materialreductions in emissions and provide a bridgeto a lower carbon energy future.
That is why the participants of the CO2
Capture Project (CCP) decided to worktogether and collaborate with governments,industry, academic institutions andenvironmental interest groups, to developtechnologies that will reduce the cost of CO2
capture and demonstrate that underground, orgeological storage is safe and secure.The goalis to reduce the impact of fossil fuel basedenergy production and use - at a time whenglobal energy demand is growing faster thanever - all at an affordable cost.
Industry and government jointly fund theproject, and the technology research anddevelopment is carried out by a wide range of academic and commercial institutions, allsubject to open and comprehensive peerreview.The views of external groups, such as Non Governmental Organisations (NGOs),are also being incorporated.Throughinternational public-private collaboration of thiskind, we believe the CO2 Capture Project canmake a real difference; co-operating for abetter environment.
Gardiner HillManager, Environmental Technology Programme, BPChairman, CCP Executive Board
An external viewpoint...There are many ways to reduce CO2
emissions. Our focus should be to minimiseenergy use by improving energy efficiency. Atthe same time, we should move as quickly aspossible towards renewable energy sourcessuch as solar and wind.
If CO2 capture and storage is pursued tocomplement rather than to compete withefficiency and renewables, a number ofNGOs feel it could play a useful interim rolein reducing CO2 emissions. In particular, itmay have the potential to help bluntemissions from the hundreds of coal andgas-fired power stations that will be builtover the next few decades, especially in fastdeveloping economies like China. It couldalso help facilitate a bridge to a futurehydrogen economy based on renewables bystimulating investment in the necessaryinfrastructure. But the technology is at arelatively early stage of development andthere are long-term economic, safety andregulatory concerns that need to beaddressed.
Only by carefully considering the issues andworking together can we hope tosuccessfully address the problem of CO2
emissions. By actively engaging withenvironmental interest groups like ClimateAction Network Europe, the CO2 CaptureProject is pursuing research into carboncapture and storage that is mindful of ourconcerns, and is sharing information thathelps us better understand the technologiesand their potential.
Jason AndersonClimate Action Network Europe
Climate Action Network Europe co-ordinates the climate policyactivities of environmental NGOs at European Union level
1
2
Climate Change
The nature of CO2
Carbon dioxide, or CO2, is a colourless, odourless
gas that exists in the atmosphere at trace
concentrations. Although invisible, it is
fundamental to life on earth - plants use CO2 in
photosynthesis and return CO2 to the
environment when they decay. Carbon is also
emitted from volcanoes, dissolved in the oceans,
and bound in minerals. All of these factors affect
the level of CO2 in the atmosphere.
Along with other gases, CO2 plays an important
role in regulating the Earth’s climate, letting
sunlight pass through the atmosphere to warm
the planet, but hindering the escape of heat.This
is known as the greenhouse effect, without which
the Earth’s average temperature would be a
chilly -18 degrees Celsius.
CO2 and climate changeSince the Industrial Revolution, humans have
altered the pace of the carbon cycle by extracting
and burning fossil fuels (oil, gas and coal) and by
replacing forests with farmland. These actions
have released billions of tonnes of CO2.
Ice cores and other lines of evidence tell us that
since 1750, there has been a 30% increase in the
amount of CO2 in the atmosphere, from about
280 to 370 parts per million (ppm).
Evidence also shows that past increases in
atmospheric CO2 were associated with climatic
warming. Since the 19th century there has been a
0.5 degrees Celsius rise in global average
temperature and there is a consensus view that
this is largely due to rising CO2 levels caused by
burning fossil fuels.
At our current pace, CO2 is expected to reach
double the pre-industrial level by the end of this
century. At the same time, the Earth’s
temperature is expected to rise by 1.4 to 5.8
degrees Celsius, a rate of change that appears to
be unprecedented in the last 10,000 years.
Although the effects of this warming would vary
with geography, it is predicted to lead to
increased threats to human health from disease
and extreme climate events. Agriculture and
ecosystems would likely be adversely affected in
many regions. Precipitation patterns may change.
Water shortages may become more serious in
water-scarce regions, and low-lying coastal regions
would face increased risks of flooding. The
combined economic and social impacts of these
changes could be large, particularly for developing
countries.
Stabilising CO2 levelsTo avoid the predicted consequences of climate
change, it is necessary to stop the atmospheric
level of CO2 rising. But because the climate
system takes time to equilibrate, CO2
concentrations will continue to rise for a time
even as emissions are decreased. If emissions
were held at current levels for the next 50 years,
for example, society would be on track to
stabilise at a concentration of 500 ppm (versus
370 ppm today).
The chart below is a summary of the main sources
of CO2 emissions from fossil fuel combustion.
Given the increasing demand for energy,
particularly in rapidly developing economies, the
International Energy Agency predicts that CO2
emissions from these sources will increase by
around 70% by 2030. Coal-fired electricity
generation for example is set to double during
this timeframe.
If we are to work towards the stabilisation of CO2
emissions, then strategies need to be found that
will supply the additional energy required without
releasing more carbon to the atmosphere.
The options include renewable energy (e.g. solar,
wind and biofuels) switching to cleaner fuels (e.g.
from coal to natural gas), nuclear energy,
increased energy efficiency and CO2 capture and
storage. It is clear that no one strategy will be
sufficient to tackle the problem. A portfolio
approach will be required.
1000 1200 2000180016001400
300
280
260
320
CO2
(ppm
)
Year
340
360
Industry6.5
Sources of CO2 emissions from fossil fuel combustion (billions of tonnesof CO2 per year)Source: International Energy Agency (IEA) 2003
Source: IPCC
Power Generation8.0
Global atmospheric concentration of CO2
Transport5.5
Residential2.0
Other1.5
General Overview CO2 Capture & Storage
3
CO2 Cost Chain
Indicative costs only
CO2 Capture CO2 Transport CO2 Geological Storage
$3-160/tonne $1-25/tonne $2-5/tonne* Total= $6-190/tonne
Typical Depth
CO2 trapped betweengrains of rock
1km
2km
3km
What is CO2 capture and geological storage?The idea is to capture CO2 from large industrialsources, before it is emitted to atmosphere, and tostore it deep underground in secure geologicalformations, where it would be trapped indefinitely. Ifapplied to some of the world’s major CO2 emissionssources, such as coal and gas-fired power stations andother major industrial facilities, this could reduceatmospheric emissions of CO2 by millions of tonnes per year.
Experience and understanding of CO2 in bothindustrial and natural settings is the basis forconfidence in the feasibility of capture and storageschemes. CO2 is found naturally in geologicalformations around the world, where it is trapped inmuch the same way as other fluids, such as oil andnatural gas. It is also a familiar industrial commoditywith a wide range of uses, from the carbonation ofdrinks to refrigeration, cooling and food preservation,pH control, welding, chemicals manufacturing andenhanced oil recovery.
Much of the technology used in these industriescould be adapted for capture and storage. Buttechnical know-how is only part of the story. TheCCP has identified the key issues that need to beaddressed before CO2 capture and storage can bewidespread.
CostToday, the technology to capture and store CO2 isexpensive.The table below shows CCP research-based estimates for each stage of the process.Themost expensive - the separation and capture ofCO2 in the first place – varies according to thesource (please see CCP baseline calculations forfour real life emissions scenarios on page 6).Implementation of individual CO2 capture andstorage schemes will depend on assessment of thecost versus benefit compared with other climatechange mitigation options and on the financialincentives that are put in place to reducegreenhouse emissions, for example throughemissions trading schemes. In the meantime, thedevelopment of advanced, lower cost technologiesincreases the scope of potential application.
Public AcceptanceThe acceptance of capture and storage as a viableclimate change mitigation option depends on thelevel of confidence in the ability of geologicalreservoirs to trap CO2 for long periods of time, aswell as a clear understanding of the benefits andrisks involved. Appropriate regulations also need tobe developed in order to establish and enforceappropriate standards and responsibilities for theimplementation of capture and storage schemes.
*not including long term monitoring Cost principally distance dependentCost depends on CO2 source
1mm
Research contractsOver 200 projects were initially evaluated and atthe end of 2001, over 80 contracts were signedwith a range of national, academic and commercialinstitutions.The project teams have been managedand co-ordinated by technology experts from eachof the eight funding companies. A full list of CCPresearch projects can be found on pages 18 &19.
Peer review At key decision points, CCP projects and decisionswere peer reviewed by a Technology AdvisoryBoard (TAB) comprising independent experts fromindustry and academia as well as representativesfrom the three funding governments.The TABprovided challenge to the project teams, advice onexternal benchmarking and peer review andassurance that the best technical practices wereemployed in delivery of the project.
External engagementNGO focus group meetings were held in 2002 and2003, providing an opportunity for the CCP toshare interim results and for open dialoguebetween industry, government and environmentalinterest groups from Europe and America.
NGO Participants at 2003 Focus Meeting:• Natural Resources Defence Council (NRDC)• Climate Action Network Europe (CANe)• Keystone Centre• Pew Centre• Bellona Foundation
Technical papersTechnical papers have been delivered at severalindustry conferences, notably the InternationalEnergy Association’s (IEA) Sixth Greenhouse GasTechnology conference (GHGT-6) in Kyoto, Japan.At the time of publication, submissions are beingprepared for the Seventh Greenhouse GasTechnology conference (GHGT-7) in 2004.
4
The CO2 Capture Project
CCP cash contributions
Funding / $ millions 8 companies 3 governments total
Economic modelling 0.5 0.5 1.0Post-combustion capture 1.5 1.5 3.0Oxyfuel capture 1.0 1.0 2.0Pre-combustion capture 4.0 4.0 8.0Storage, monitoring and verification 4.0 4.0 8.0Technical Sub-total 11.0 11.0 22.0Non-technical 3.0 3.0
Total 14.0 11.0 25.0
250
Apr 2000 Aug 2000 Sep 2001 Dec 2002 Dec 2003
200
150
100
50
0
start-up phase delivery of results
>200 technologies reviewed
numb
er o
f techn
ical p
rojec
ts
All numbers rounded to nearest $500,000
Over 80 contracts signed Technology options screened and focused
Optimum technologies taken toproof of feasibilityReview and Evaluation Analysis Technology Development
In the first phase of the project, a wide range of technical studies were selected to complement other researchprogrammes underway around the world.The overall aim was to advance the scientific basis for capture andstorage and expand the potential scope of implementation.
CCP objectives
1.To identify and develop technologies to reduce the cost of CO2 capture by 50%-75%.2.To identify best practices and reduce uncertainties associated with geological storage of CO2.
CCP Timeline
CO2 has been captured from both natural and industrial sources for many years.Thechallenge for wide scale application is to reduce costs and to develop technologies thatcan be applied to the world’s largest CO2 sources, ranging from coal and gas-fired powerstations to oil refineries, chemical plants and iron and steel production facilities.The threemain techniques for CO2 capture are outlined below.
Post-combustion captureCO2 can be captured from the exhaustgas after a fuel is burned, using solventssuch as amines, in a process known asabsorption.The CO2 is absorbed by theamines at particular temperatures andpressures and can be removed by varyingthe temperature and pressure.
Oxyfuel captureFossil fuels can be burned in pure oxygenrather than in air.This results in a highercombustion temperature and when CO2
capture is not required it is inherently moreexpensive, but when CO2 capture isrequired, it gives the advantage of an exhauststream composed almost exclusively of CO2
and steam.The CO2 can be captured simplyand cheaply by condensing the steam.
Pre-combustion captureThe pre-combustion capture process isbased on two main steps; first, theconversion of a fossil fuel into a mixturecontaining hydrogen and CO2 (known assyngas) and second the separation of theCO2, leaving the hydrogen to be used as aclean fuel.The combustion of hydrogenproduces no CO2 emissions and the mainby-product is water.
CO2 capture and storage and
the hydrogen economy
Hydrogen is often cited as a fuel of thefuture in everything from transport to homeheating to large scale electricity production.Whilst the advantages and disadvantages arestill being debated, the key benefit is thatcombustion of hydrogen produces virtuallyno Greenhouse Gas (GHG) emissions.Themain by-product is water. It is one of the fewfuels that could substitute for oil in thetransport sector, which is forecast to accountfor the highest proportion of the expectedgrowth in energy demand over the nexttwenty years.
Hydrogen can be produced by theelectrolysis of water using renewable energy,such as solar or wind power, but the cost iscurrently prohibitively high for wide scaleapplication. One potential advantage of pre-combustion capture is the opportunity toproduce large quantities of hydrogen costeffectively from fossil fuels. Combined withgeological storage of the CO2, this couldoffer a low cost, zero emissions pathwaytowards the introduction of hydrogen as afuel, stimulating investment in keyinfrastructure and reducing overall CO2
emissions in advance of large scalerenewables-based hydrogen production.
CO2 Capture General Overview
5
Oxygen (O2)
Hydrocarbon fuel (CH4)
Stream (H2O)
Combustion
Carbon dioxide (CO2)to storage
Air (N2,O2)
Hydrocarbon fuel (CH4)ustion
Carbon dioxide (CO2)to storage
Steam &Nitrogen
2O,N2)
AmineTower
Air (N2,O2)Hydrocarbon fuel (CH4)
Combustion
Carbon dioxide (CO2)to storage
Hydrogen (H2)
Steam (H2O)
Steam &Nitrogen(H2O,N2)
Diagrams representing 3 methods of CO2
capture applied to a gas-fired power station.
Hydrogen fuel cell vehicle
© c
ourt
esy
of D
aim
lerC
hrys
ler
Scenario Fuel source CO2 source Retrofit / Uncontrolled Baseline capture new build emissions/million cost* / $ per tonne
tonnes CO2 per year CO2 avoided
Distributed gas Natural gas Small distributed Retrofit 2.6 $88/tonneturbine power turbinesgeneration, Alaska
Grangemouth Hydrocarbon Heaters & boilers Retrofit 2.6 $78/tonnerefinery, UK gas & liquids
Gas-fired power Natural gas Large electric New build 1.3 $62/tonnestation, Norway power generation
turbines (CCGT)
Coke gasification Solid gasification Steam, H2, & New build 4.9 $15/tonnescheme, Canada (petroleum coke) electricity
cogeneration
6
CO2 Capture Project Results
CCP Emissions Scenarios
Grangemouth refinery - 1 of the 4 CCP
emissions scenarios
*using current bestavailable technology
Research team focus
The CCP set up research teams to examine eachof the three methods of CO2 capture (post-combustion, oxyfuel and pre-combustion) and eachteam was led by experts from the eight fundingcompanies.The primary focus was to identify anddevelop a range of practices and technologies thatcould reduce the cost of CO2 capture and wouldbe suitable for a wide scale implementation,including coal, oil and natural gas based applications.
Cost reduction objective
The ambitious nature of the CCP’s cost reductiontarget - to identify technologies that could reducethe cost of CO2 capture by 50-75% - reflects thefact that for CO2 capture and storage to play asignificant role in reducing emissions over the nextfew decades, a lot needs to be done in a shortspace of time, especially when compared to theusual pace of technology development. It isimportant to note however that any cost reductionachieved effectively expands the potential scope ofcapture and storage schemes.
Emissions scenarios and common economic model
In order to facilitate the development of technologiesthat would be suitable for a range of emissionssources, the CCP’s capture programme was basedaround four real-life emissions scenarios.Two of thescenarios (an oil refinery and distributed gas-firedpower generation turbines) were existing facilities,requiring the retrofitting of capture technologies,whilst the other two (a gas-fired power station andcoke gasification scheme) were new-builds, whereCO2 capture could be incorporated from theplanning stage.
In each case, the first step was to establish the totalcost of CO2 capture using the best currently availabletechnology, providing a baseline against which the newtechniques could be compared.This was done usingthe Common Economic Model (CEM), developedspecifically by the CCP to calculate the total costs ofdifferent capture technologies in different settings.Themodel uses standardised input and material costs inorder to allow direct and meaningful comparison ofone technology to another as well as taking intoaccount the total energy requirements of building andmaintaining the capture facilities to give an overall cost(in $ per tonne) of CO2 avoided for each technology.
7
The post-combustion research programmeThe post-combustion team was charged withevaluation of existing technologies that may beuseful at the large scale required for captureand storage as well as to stimulate newtechnology development.The studies includeddetailed analysis of the best currently availabletechnology (used for the baseline calculationsfor the four scenarios) to identify all cost-reduction opportunities.This work was donein two stages, first to reduce costs for a stand-alone separation plant and second toinvestigate the integration of the separationplant with the power plant. Other researchgroups identified and tested the advancedsolvents that could be used for post-combustion capture. Better adsorbents, newchemical approaches and alternativeequipment technologies were also investigated.Finally, the post-combustion team defined whatis referred to as BIT (Best IntegratedTechnology), based on a combination of thestudied technologies.
Key findings• Changes to the design and integration of
current technologies could significantly reducethe cost of post-combustion capture andwould be applicable at large scale.Testing isrequired to confirm the viability and cost-reduction potential.
• The combination of two establishedtechnologies – the MHI KS-1 solvent and theKvaerner membrane contactor – offers thepotential to reduce energy consumption, andhence operating cost, for the post-combustion process.
• The combination of simplified designstandards and advanced solvents / membranecontactors in a Best Integrated Technology(BIT) case could reduce the cost of theoverall CO2 capture process by around 50%although more work is required to test theseprocesses. It is considered that this advanced,lower cost technology could be commerciallyintroduced before the end of this decadewith ongoing development work.
• Some novel chemical and process ideas forpost-combustion capture have beendeveloped, with the potential to deliversignificant cost reductions, although morework needs to be done before the costreduction potential can be properly assessed.
The oxyfuel research programmeThe oxyfuel team looked at the potential costsavings that combustion using pure oxygen(known as oxyfiring) may give compared toconventional combustion in air.The goal wasto establish a ‘baseline’ for oxyfuel captureusing existing technology as well as to researchnew techniques. One key aspect of the workwas to investigate the adaptation of currentboilers, heaters and turbines to cope with thehigher combustion temperatures that resultfrom oxyfiring - either by redesigning keycomponents or by reducing the temperatureby recycling some of the CO2 from theexhaust gas and pumping it back into thecombustion chamber (known as exhaust gasrecycling). Other studies focused ontechniques to reduce the cost of separatingoxygen from air in the first place - such asoxygen transfer membranes (known as ionictransport membranes) and chemical looping(transferring oxygen to the fuel by means of ametal oxide acting as an oxygen carrier).
Key findings• Exhaust gas recycling is an extremely
promising near term option that can beretrofitted to existing heaters and boilers. Itcould also be combined with state-of-the-artair separation techniques to reduce CO2
capture costs even further.
• The conversion of gas turbines to oxyfiringhas high potential but is a longer termproposition.
• The development of boilers, heaters andturbines that can operate at hightemperatures would pave the way forfurther cost reductions but requires newmetallurgy and is a longer term prospect.
• The chemical looping and ion transportmembrane studies have shown some highlypromising results and could significantlyreduce the cost of separating oxygen fromair, although further research anddevelopment is required in both cases.
The pre-combustion research programmeThe CCP pre-combustion team looked at theintegration of existing technologies into onecomplete process as well as the developmentof advanced techniques for steam reforming and hydrogen separation, including selectivehydrogen transport membranes and newadsorbent materials that could be used in a reaction known as ‘sorbent-enhanced water gas shift’.
Key findings• Pre-combustion capture technologies can
be applied to all fossil fuel sources and offer the opportunity to reduce the cost of CO2 capture for all four of the CCP scenarios.
• Sorption enhanced water gas shift andmembrane enhanced water gas shifttechnologies offer considerable cost-reduction opportunities.
• An advanced hydrogen membrane reformersystem, developed for the Norwegian gas-fired power station scenario, shows the highest cost reduction potential for any CCP capture technology, althoughconsiderable additional testing is required.
CO2 Capture Project Results
8
Conclusion
CO2 Capture Project Results
Once the capture technologies beingdeveloped by the CCP had been taken toproof of concept stage, the mostpromising were subjected to a moredetailed cost assessment.The results haveshown significant potential savings for allscenarios, ranging from 16% for the cokegasification scheme to 60% for the gas-fired power station.
Whilst different technologies are atdifferent stages of development, the widerange identified by the CCP means thatthey could be suitable for many of theworld’s major emissions sources.Techniques developed for gas-fired powergeneration for example could also be usedfor coal-fired power generation, ifcombined with the gasification of coal.
Pre-combustion capture, where some ofthe most significant advances have beenmade, is applicable to all fossil fuel sourcesand may also offer the opportunity toproduce large amounts of hydrogen cost-effectively, helping to stimulate thedevelopment of a hydrogen based energyeconomy in the future.
With continued public-privatepartnership, the next step will be to worktowards the commercial scaledemonstration of the most promisingtechnologies developed by the CCP aswell as the achievement of further costreductions.This is helping to bring forwardthe day when society could benefit fromcleaner energy from fossil fuels.
0
20
40
60
80
100
Gas turbinesAlaska
Oil RefineryUK
Gas-fired power station Norway
Coke gasificationCanada
Best currently availale technologyBest new (CCP) technology$88
$72$78
$48$62
$24
$15 $12
Potential cost savings of best CO2 Capture Technologies
$ pe
r tonn
e CO
2avoid
ed
Cost reductions determined using Common Economic Model with generic (US Gulf Coast) material costs and standardised energy prices
Potential cost savings of CCP Capture TechnologiesAlaska distributed gas-fired UK oil refinery Norway natural Canada coke
power generation gas power station gasification
Baseline cost (best currently available technology) $ per tonne of CO2 avoided $88.2 $78.1 $61.6 $14.5
CCP developed technologies cost / $ per tonne of CO2 avoided (% variation from baseline)
Pre-combustion capture technology
Membrane water gas shift (GRACE & DOE-membrane) $48.1 (-38%)Membrane water gas shift (GRACE & Pd-membrane) $52.4 (-33%)Sorption enhanced water gas shift $71.8 (-19%)Sorption enhanced water gas shift - O2ATR $42.7 (-31%)Sorption enhanced water gas shift - AirATR $34.4 (-44%)Very large scale auto thermal reformer $76.0 (-14%)Hydrogen membrane reformer $24.4 (-60%)Advanced coke gasification $12.2 (-16%)
Post-combustion capture technology
Nexant integrated baseline design $35.1 (-43%)MHI solvent (KS1) with Kvaerner membrane $47.5 (-23%)Best integrated technology (Nexant BL integrated & MHI-KS1) $28.2 (-54%)
Oxyfuel capture technologyOxyfiring with flue gas recycle & ionic transport membranes (ITM) $41.0 (-48%)Oxyfiring with flue gas recycle & ASU $48.7 (-38%)
Geological storage involves compressing the CO2
captured from industrial sources and injecting it intosuitable rock formations, typically thousands ofmetres below the Earth's surface, where it wouldbe trapped indefinitely.
Possible sites for CO2 storage occur all around theworld.Two of the main options are producing ordepleted oil and gas fields.These have theadvantages that the geology is generally wellunderstood and they are proven traps, having heldfluids (often including CO2) at high pressure formillions of years. CO2 is already injected into someoil fields to increase oil production (please see textbox on page 10 entitled 'relevant industryexperience') and in some cases, the infrastructurebuilt up to recover the oil or gas (e.g. injectionwells, pipeline transportation networks) could beadapted to put CO2 back into the reservoir.
Other storage options include unmineable coalseams (where the CO2 would be adsorbed ontothe coal) and deep salt water bearing rockformations, also known as saline formations.
The CCP has looked at all of these storage optionsalthough the research has focused principally onproducing and depleted oil and gas fields and deepsaline formations as these are considered to havethe greatest global storage potential (see 'estimatedstorage capacity' table below). CO2 would betrapped in permeable rocks (i.e. sandstones),capped by impermeable rocks (i.e. shales).
Estimated Storage CapacityStorage option Global capacity
Gt CO2 % emissions to 2050
Depleted oil and gas fields 920 45Deep saline reservoirs 400-10,000 20-500
Source: IEA Greenhouse Gas R&D Programme
CO2 Storage General Overview
9
Photograph of sandstone reservoir rock
(magnified 15x)
© c
ourt
esy
of O
N C
omm
unic
atio
n
TypicalDepth
2km
1km
3km
Main Geological Storage Options
1. Saline formations (salt water bearing rock)
2. Oil and gas fields
3. Unmineable coal seams
Key issues
Notwithstanding the current level of knowledgeand experience that can be applied to CO2
storage, the CCP has identified a number of keyissues that need to be addressed before thepractice can be widespread.
Identifying appropriate storage sitesThe ideal storage reservoir would be one in whichCO2 can be trapped permanently in place andwhere the risk and potential impact of leakage isminimised. Selecting the most appropriate sitesrequires a detailed understanding of differentgeological formations and the behaviour of CO2
within these formations, including the factors thatlead to permanent trapping of CO2 and thefeatures that could lead to leaks to the surface.
Responding to leaksIt is important to understand the likelihood of CO2 leakage from different storage sites and thepotential impact on ecosystems close by, as well asto have remediation strategies in place to addressthe causes and consequences of leaks. It is alsoimportant to establish an 'acceptable' rate or levelof leakage, above which remediation plans wouldbe acted upon.The issue of CO2 leaks will be keyto public acceptance of CO2 storage.
Monitoring Once injected into a reservoir, the movement ofCO2 will need to be monitored, both to assess theongoing integrity of storage and to identify thenature and rate of any leaks.The challenge is toidentify and develop cost effective techniques thathave the appropriate resolution and that can bemaintained over long periods of time.
Handling, transporting and injecting CO2
CO2 is already transported by ship and pipeline formany industrial applications.The challenge is toidentify the most efficient and appropriatetechniques for transportation and injection,especially considering the scale of the infrastructurethat would be required in order to make asignificant difference to world CO2 emissions.
CostThe implementation of CO2 storage schemes willdepend on an assessment of the whole-life costs of individual projects compared to other climatechange mitigation techniques as well as on themechanisms put in place to offset the cost ofemissions reduction, such as emission trading schemes.
Policies and regulationsPolicies and regulations are required at a global andnational level in order to establish consistentstandards for geological storage. An appropriatemonitoring and verification framework is alsoneeded to achieve wide scale recognition andcrediting. For example, the European Union'sEmissions Trading Scheme's monitoring andverification guidelines do not yet have any provisionfor CO2 capture and storage. In general, there islittle policy development specific to capture andstorage, although several countries are now movingin that direction. Furthermore, internationalconventions that may have a bearing on geologicalstorage, such as the London Convention and theOSPAR Convention, need to be clarified beforewidespread implementation can take place and mayat present discourage the deployment of CO2
capture and storage schemes.
10
CO2 Storage General OverviewRelevant industry experience
The practice of CO2 storage is underpinned bythe experience and technology built up by theindustries that handle fluids, such as oil, naturalgas and CO2, on a daily basis. A wide range ofmodern day practices can be employed, fromthe laboratory analysis of rocks to assess thestorage potential of individual reservoirs, to time-lapse 3D seismic surveys to track the movementof CO2 underground.
One important area of expertise is the use ofCO2 for enhanced oil recovery (EOR). In manyparts of the world,CO2 is injected into producingoil fields,where it pushes oil towards theproduction wells. Practices for the safe handling,transportation and injection of CO2 are wellestablished and,while most of the CO2 is currentlyrecycled, some schemes might be adapted to trapCO2 permanently in the reservoir. This is apromising near term option as the cost ofimplementing the storage scheme would bepartially offset by additional oil production.
Natural gas storage is another key area ofexperience. Natural gas is currently stored ingeological formations, including those suitable forCO2 storage, such as saline formations anddepleted gas fields, to help deal with variations indemand at different times of the year. Many ofthe practices employed by the industry, includinginjection, monitoring and remediation techniques,would also be applicable for CO2 storage.
Based on the experience and understanding ofindustries like these, a number of CO2 storagedemonstration projects are already underway.TheWeyburn project in Canada is combining EORwith CO2 storage, whilst in the NorwegianNorth Sea, Statoil is storing around one milliontonnes of CO2 per year in a deep salineformation. In the Algerian desert, the In Salah gasproject is being set up to store CO2 in a gas field.
3D seismic combined with
satellite surface imagery
The CCP's storage programme should be viewedin the context of the wider body of workunderway around the world. Having surveyed theportfolio of projects sponsored by other agencies,such as the EU, US and Australian governments,the CCP identified key issues that were notaddressed elsewhere and that were consideredimportant in order to make CO2 storage apractical reality.
The work was organised into four key areas (see below) and 30 technical studies werecommissioned with the overall objective ofreducing uncertainties and identifying bestpractices for geological CO2 storage.
The Storage Programme Structure
Integrity - Assessing the competence of natural and engineered systems to contain CO2
(The research in this area fed into the riskassessment work).
Optimisation - Improving the efficiency andeconomics of transporting and storing CO2.
Monitoring - Developing techniques to trackCO2 movements in and beyond the storagereservoir.
Risk assessment - Developing a formalisedframework to quantify and minimise theprobability and impact of CO2 leakage fromstorage sites.
IntegrityGeological systems are complex and thus varywidely in their suitability for long-term CO2
storage. Engineered systems such as wells,although necessary for operation of CO2 storagefacilities, introduce additional vulnerability to CO2
leakage. The CCP “integrity” studies addressedissues related to the natural and engineeredfeatures of geological reservoirs.
Key findings• Analysis of why naturally occurring CO2
accumulations do or do not leak highlightswhich features (e.g. reservoir and cap rockgeometry, lithology) are amenable to secureCO2 storage.
• Simulations of physical and chemical interactionsof CO2 with reservoirs (minerals) and fluids(oil, gas, water) show that CO2 is trapped(immobilised) by a variety of methods:
- Buoyancy of the CO2 phase relative toreservoir water results in upward migrationwhere CO2 is trapped by cap rock.
- Solubility trapping (where CO2 dissolves intothe water in the reservoir) is effectivedepending on salinity and reservoir conditions.
- Pore space trapping of CO2 via capillary forcesis recognised as a major trapping mechanism.
- Mineralisation of CO2 to form carbonates is arelatively minor, long-term trapping mechanism.
• Two independent reservoir simulations showthat much of the injected CO2 would beeffectively trapped over a hundred-year timeframe and most over a thousand-year timeframe. Different completion and injectionstrategies can be used to maximise CO2
trapping.
• Experimental work and modelling of thegeochemical and geomechanical effects of CO2
injection on reservoir and cap rocks can be usedto establish safe rates and capacity of CO2
injection. 3D effective stress analyses can beused to predict activation of faults due to CO2
injection.
• The integrity of engineered systems, particularlywells, was identified as a particular vulnerabilityin CO2 storage. There is a need to developresistant materials for use in new wells andremediation techniques for old wells.Nevertheless, even in a worst case scenario ofwell failure, most CO2 would remain in thereservoir for at least 100 years, allowing timefor well remediation.
OptimisationThe optimisation program sought to takeadvantage of processes used by other industriesto efficiently transport, inject and manage gases.Potential economic offsets to CO2 storage costsin the form of enhanced oil and gas recovery, oruse of existing infrastructure, were also addressed.
Key findings• Adapting enhanced oil recovery (EOR)
schemes may offer some of the earliestopportunities to implement CO2 storageprojects while recovering some or all of thecosts associated with CO2 capture,transportation and storage facility management.Key issues that need to be addressed includethe applicability of the EOR industry experience(mostly in West Texas) to more diversereservoir types and identifying the economictrade-offs between oil production and ultimateCO2 storage.
• CO2 storage in depleted gas fields (with orwithout enhanced recovery) offers theadvantages of existing transport and injectioninfrastructure as well as proven gascontainment. The CO2 capacity of gasreservoirs may be up to 5 times that of theoriginal hydrocarbons due to the highcompressibility of CO2.
• The natural gas storage industry, with itsextensive European and North Americaninstallations operating safely for decades, offersa viable analog to CO2 storage. Site assessmentcriteria, leakage paths and some interventionstrategies are available for application to CO2
storage.
• The economic feasibility of some CO2 storageprojects will depend on the extent to whichconventional carbon steel can be used in longdistance pipelines. Experimental and theoreticalstudies indicate that existing, stringent hydrationspecifications to avoid corrosion might berelaxed under some circumstances.
• Impurities such as SOx and NOx left in post-capture CO2 streams (for the sake ofeconomy) may have a deleterious effect onsurface equipment (compressors, pipes etc.)but appear unlikely to affect CO2 storageperformance or effectiveness of CO2 EOR.
CO2 Storage Project Results
11
12
MonitoringThe CCP’s monitoring studies evaluated theapplicability and cost-effectiveness of a broadrange of technologies from various vantagepoints, including subsurface imaging of CO2
movement and surface / atmospheric monitoringof CO2 leakage. Selection of the appropriatemonitoring program will depend on site-specificfactors and the monitoring timeframe envisioned.
Key findings• Storage sites can be monitored from a variety
of perspectives, from subsurface geophysicalimaging of CO2 movement to remote (satellite/ aerial) detection of diffuse and point sourceleakage.
• Remote surveys (e.g. geobotanicalhyperspectral) can detect CO2 leakage to thesurface indirectly by identifying resultant changesin plant life and mineral assemblages.Adaptation of the instrumentation to directdetection of CO2 might provide betterresolution and broader applicability.
• Conventional geophysical techniques such astime-lapse (4D) seismic have beendemonstrated as effective in monitoring CO2
movement in the subsurface in some settings.Lower resolution techniques such as gravity,electromagnetics and streaming potential,however, may offer adequate alternatives andlower costs.
• Natural and introduced tracers such as noblegases offer a sensitive, cost effective means ofmonitoring CO2 migration paths in thereservoir as well as leakage out of the reservoir.
• Ground-based laser spectrometry techniques,properly configured with respect to theanticipated type (diffuse versus point source)and magnitude of leaks, are cost effective, wellestablished monitoring techniques.
Risk assessmentRisk assessment applied to geological storage ofCO2 is relatively new although the generalprincipals have been applied in other industries.The CCP risk assessment studies range fromcharacterising the leakage vulnerability ofindividual geological and engineered features toholistic “systems” approaches that predict howthese features will interact in a given local setting.For the risk assessment process to be acceptableto regulators and the public it has to beconducted logically and transparently with activeengagement of stakeholders.
Key findings• An initial survey study put into perspective the
hazards associated with CO2 handling relativeto that of other industrial materials. Thephysical and chemical characteristics of CO2 arewell understood from a health, safety andenvironment perspective and a regulatoryframework for its use is available.
• A study on early detection, intervention andremediation of CO2 leakage outlines possiblescenarios and impacts as well as identifyingtechnologies that might be used in response.
• Simulation of CO2 movement to the near surface(vadose zone) and into the atmosphere predictsCO2 dissipation patterns for different leakagerates and volumes (flux) at given localities.
• Two comprehensive risk assessmentmethodologies were developed. Each allowsfor the identification of risk factors for leakageand a quantifiable assessment of likelihood andconsequences of occurrence. Preliminarytesting has been conducted on a North Seaaquifer model and a Colorado coal bed. Theformer showed no leakage over a 10,000-yeartimeframe, and the latter showed how specificpractices (e.g. well placement) can be used toavoid CO2 leakage.
• Subsurface microbial ecosystem changes inducedby CO2 injection warrant attention because ofpotential production problems arising frommineral dissolution and gas generation.
• The next logical step in risk assessment includesstandardisation of FEPs (features, events andprocesses) and formal benchmarking withmethodologies developed by other organisations.
One of the main achievements of the CCP hasbeen to view potential geological storage sites as holistic systems and to introduce a new, risk-based approach that takes into account all of the factors that could influence the integrity ofstorage as well as the likely consequences ofCO2 leaks.The next step will be to test andrefine the risk assessment methodologies in thefield but, if proven, they could offer a soundscientific basis for site selection, as well asidentifying the most appropriate monitoring and remediation strategies.In addition to this, the modelling work funded by the CCP is increasing understanding of howCO2 is trapped underground and increasingconfidence in the long-term storage ability ofgeological reservoirs.
Other studies are helping to identify the besttechniques for transport and injection of CO2 aswell as for cost effective, long-term monitoring.Optimising the processes and materials involvedin geological storage brings forward the daywhen it could be commercially applied.
By funding and co-ordinating a range of researchprojects like these, the CCP is helping to confirmthe potential of geological storage and to buildthe scientific and technical basis forimplementation. In the next phase, the focus will be on the integrity of well bores (which passthrough the geological formations), furtherdevelopment of the assurance processes(monitoring, verification and risk assessment) and to work towards field demonstrations of the most promising techniques.
With the continued co-operation ofgovernments, industry, academia andenvironmental interest groups, the CCP couldhelp to establish a new economic, regulatoryand technical basis for the wide scaleimplementation of geological storage schemes,helping to significantly reduce CO2 emissions to atmosphere.
Conclusion
CO2 Storage Project Results
There are many factors that impact the world'senergy mix, including social and economicdevelopment, security of supply, local environmentalimpact and global climate change. Optimising thebalance between these factors means that energy is likely to come from a wide range of sources inthe future.
Given the increasing demand for affordable energy,particularly in fast developing economies like Chinaand India, the International Energy Agency predictsthat fossil fuels will continue to dominate energysupply for many years to come.
In order to tackle climate change, the impact offossil fuels must be reduced, and whilst improvingenergy efficiency will help, it will not be enough onits own. For this reason, CO2 capture and storage is firmly on the international agenda.
The governments, companies and researchorganisations involved in the CCP have identifiedtechnologies that could halve the cost of CO2
capture and are advancing the scientific andtechnical basis for long-term geological storage.
This is helping to establish CO2 capture andstorage as a viable climate change mitigation option,one that could complement the development ofnew energy sources, contribute to materialreductions in CO2 emissions and meet the needs of societies around the world. It may alsoprovide a low-cost, zero emissions pathway to the hydrogen economy.
Ultimately, implementation will depend on confidencein the capacity of geological reservoirs to store CO2
as well as the policies and incentives that are put inplace to address the issue of climate change. But,with the potential to minimise emissions from someof the largest CO2 sources in the world, CO2
capture and geological storage could become a keypart of our response to climate change.
More work is needed before CO2 capture andstorage is applied on a wide scale and the CCP plans to address the key issues in their nextphase.The proposed programme themes areoutlined here.
CCP phase 2 (2004-07): program themes
Capture Technology • Continued cost reduction
• Further development of short-listed technologies
• Focus on current and new technologies
• Pilot scale demonstration of a capture technology- possibly via strategic partnerships
Storage Technology• Assurance (monitoring, verification & risk
assessment)
• Well integrity
• Demonstration projects - possibly via strategicpartnerships
Industry Standards and Public Acceptance• Protocol / industry standards for capture &
storage
• Stakeholder outreach and education
• Business environment for CO2 Capture &Storage
Networking• Crosscutting and sharing
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Project Conclusion and Next Steps
14
Post-Combustion Capture ProgrammeProvider Contract Co-FunderFluor Limited CCP Baseline Study CCPKvaerner Electric Swing Adsorption (ESA) CCPNorsk Hydro Channel Concept Preliminary Study CCPOakridge National Lab (UT Battelle) Post Combustion ESA & Carbon Fiber Composite Molecular Sieve (CFCMS) Study DOESRI (Stanford) Radical Chemistry (Self Assembled Nano-porous Materials for CO2 Capture) DOEKvaerner Amine Scrubbing/Membrane Contactor NORCAPMHI Amine Scrubbing/Membrane Contactor NORCAPNexant Cost Efficient Design & Integration NORCAPNorsk Hydro Radical Chemical Concepts NORCAP
Pre-Combustion Capture ProgrammeProvider Contract Co-FunderFoster Wheeler Advanced Syngas Study CCPHaldor Topsoe Pre-combustion Membrane Reactor CCPJacobs Engineering Very Large Scale Autothermal Reforming (VLS ATR) CCPAir Products Compact Reformer Membrane Contactor DOEAir Products & Chemicals, Inc. Sorption Enhanced Shift Reaction (SEER/SEWGS) DOEARI Capture Study Integration and Reporting DOEColorado School of Mines (CSM) Sulfur Poisoning Resistant Palladium/Copper Alloy Composite Membranes DOEDavey Compact Reformer Membrane Contactor DOEEltron Research Membrane Water Gas Shift (WGS) Reactor Development Study DOEEnergy Resource Centre Membrane WGS Reactor Dev. Study DOEFluor Daniel Gasification CO2 Separation Development (Advanced) DOEFluor Federal Membrane WGS Reactor Development Study DOEGeneral Electric (GE) Gas Turbine Retrofit DOESOFCo / McDermott Technology, Inc. WGS Reactor Design, scale up and cost assessment DOETDA Research, Inc. WGS Sulfur Poisoning Resistant Palladium/Copper Alloy Composite Membranes DOEUniversity of Cincinnati Zeolite Membranes & Their Applications In Membrane Reactors For WGS Reaction DOEInstitute for Membrane Technology GRACE PCDC STUDIES Membrane Reformer EU/GRACEKTH GRACE PCDC STUDIES EU/GRACENorsk Hydro GRACE PCDC STUDIES Hydrogen Membrane Technology EU/GRACESintef GRACE PCDC STUDIES Investigation of High Temperature Hydrogen Membrane EU/GRACEUniversidad de Zaragoza (UNIZAR) GRACE PCDC STUDIES Use of Pd/Zeolite Composite Membranes EU/GRACEUniversity of Twente-AMK GRACE PCDC STUDIES Membrane Activities EU/GRACEInstitute for Energy Technology (IFE) Generation of H2 Fuels NORCAPJacobs Engineering Standardized PCDC NORCAPNorsk Hydro Hydrogen Membrane Technology NORCAP
Oxyfuel Capture ProgrammeProvider Contract Co-FunderAir Products & Chemicals Ltd. Oxyfuel boilers and heaters recycle CCPAlstom Power Zero Recycle Oxyfuel Boiler Pre-Study CCPMitsui Babcock High Pressure Oxyfuel Boiler Study CCPMitsui Babcock Zero or Low Recycle Oxyfuel Boiler Study CCPSintef Oxyfuel Power Generator Cycles Study CCPAlstom Power Boilers (AV) Chemical Looping Combustion Economics and Scale-up EU/GRACEChalmers University of Technology Chemical Looping Combustion (CLC) EU/GRACEConsejo Superior de Investigaciones Particle Development, Screening & Comprehensive Testing EU/GRACEVienna Uni of Technology Chemical Looping Combustion Fluidisation Studies EU/GRACE
Cost Estimation and EconomicsProvider Contract Co-FunderEdward S. Rubin Common Economic Model (CEM) Study CCPHoward J. Herzog CEM Study CCPNorsk Hydro Cost Estimation (Nils Eldrup) CCPTelemark CCP Cost Screening Cost Estimation CCPFluor Inc. Cost Evaluation of Selected Technologies DOEPraxair Advanced Boiler Concept DOEAlstom Azep Economic Evaluation NORCAPCost Technology AS 2003 CCP Cost Screening Cost Estimation NORCAP
List of research programmes
Storage Assurance ProgrammeProvider Contract Co-FunderAdvanced Resources Int'l (ARI) Natural CO2 Field Analogs for Geological Sequestration CCPGFZ Potsdam Influence of CO2 Injection on Reservoir and Caprocks CCPHy-Vista Rangely Survey CCPIEA Greenhouse Gas Programme Gas Storage Technology CCPIEA Greenhouse Gas Programme Remediation & Early Warning Workshop / White Paper CCPLawrence Berkeley National Lab HSE Risk Assessment Literature Search, Synthesis of Findings with Roadmap CCPNew Mexico Institute Mining Tech. Leveraging EOR Studies CCPSerco Ltd. Weyburn CO2 Monitoring Project CCPTang Associates (CalTech) Atmospheric CO2 Monitoring Systems CCPVarious SMV 2002 Workshops - Santa Cruz CCPAPCRC Geomechanical Effects of CO2 Storage DOEARI SMV 2003 Workshops DOEBattelle CO2 Impurities Trade-off - Surface DOEExchange Monitor CCP 2004 Closeout Workshop DOEGeolas (Princeton) Impact of CO2 on Subsurface Microbes DOEIdaho National Lab (Idaho) HSE Probabilistic Risk Assessment Methodology DOELawrence Berkeley National Lab Investigation of Novel Geophysical Techniques for Monitoring of CO2 Migration DOELawrence Berkeley National Lab HSE Risk Assessment of Deep Geological Storage Sites DOELawrence Berkeley National Lab SMV Study Integration & Reporting DOELawrence Berkeley National Lab Remediation & Early Warning Workshop / White Paper DOELivermore National Lab Hyperspectral Geobotanical Remote Sensing for CO2 Containment DOELivermore National Lab Noble Gas Isotopes for Screening and Monitoring Long Term Migration DOELivermore National Lab Reactive Transport Modelling to Predict Long-Term Cap-Rock Integrity DOEMonitor Scientific (Sci Monitor) Top Level Synthesis of Nuclear Waste Disposal DOETNO-NITG Safety Assessment Methodology for CO2 Sequestration DOETNO-NITG CO2 Optimum Monitoring Methodology DOEON Communication Communication Consulting Services 2003/4 DOEPenn State Uni. Infrared Lasers to Detect CO2 Leakage DOESintef Long Term Sealing Capacity of Cemented Petroleum Well DOEStanford University Monitoring Aquifers & Reservoirs Using Satellite Radar Interferometry DOETang Associates (CalTech) Estimation of Capability to Monitor For Leakages of CO2 DOETexas Tech University Use of Depleted Gas & Gas Condensate Reservoirs DOETie-Line Technology (Tie-Line) Screening Tool of MMP/MME Evaluation DOEUniversity of Texas CO2 Impurities Tradeoff - Subsurface DOEUniversity of Texas (UTX) SMV Simulation DOEUtah State University (Utah State) Evaluation of Natural CO2 Charged Systems as Analogs for Geological Sequestration DOEAEA Tech / ECL Tech Optimization of Storage & Risk Assessment Methodology EU/NGCASBP Management, Risk Assessment, Monitoring & Mitigation EU/NGCASBritish Geological Survey (BGS) Methodology for Assessment of Storage Options EU/NGCASStatoil Technology Transfer EU/NGCASGEUS Basin Model Development EU/NGCASIEA Greenhouse Gas Programme Technology Transfer EU/NGCASInstitute Francais du Petrole (IFP) Basin Modelling and Geochemistry EU/NGCASERM ERM Policy & Incentives Team; Review NORCAPGas Technology Institute (GTI) Gas Storage Technology NORCAPInstitute for Energy Technology (IFE) Materials Selection For CO2 Capture & Storage NORCAPNansen Institute Legal Aspects of CO2 Underground Storage NORCAPON Communication Communication Consulting Services 2003/4 NORCAPReinertsen Engineering (Reinertsen) Transportation Properties of CO2 NORCAP
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List of research programmes
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Acknowledgments
The paper used for this publication contains 75% recycledcontent and has been awarded both the NAPM and Eugroparecycled marks. It is totally chlorine free (TCF).
Copyright ownership of all material, includingphotographs, drawings and images, contained inthis brochure remains vested in CCP Participantsand third party contributors as appropriate andacknowledged. Neither the whole nor any part ofthis material may be reproduced, redistributed,modified, or publically presented in any formwithout the express prior permission of thecopyright owner (contact Iain Wright:wrightiw@bp.com).
The information contained in this brochure isprovided on an "AS IS" basis without anywarranties or guarantees as to its accuracy oruse. The user accepts all responsibility for use ofsuch information. The user also agrees that theCCP Participants and the third party contributorswill not have any responsibility for any errors orresulting loss or damage whatsoever orhowsoever caused for any use of informationcontained in this brochure.
Produced byON Communication
t: +44 (0)1235 537 400e: on@oncommunication.com
Further information about the CO2 CaptureProject and the individual research projects canbe found at the CCP website:
www.co2captureproject.org
Information about other CO2 capture andstorage projects can be found at the website ofthe International Energy Agency (IEA)Greenhouse Gas Programme:
www.co2sequestration.info
CO2 Capture Project
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