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Can Carbon Capture and Storage Clean up Fossil Fuels
Geoffrey Thyne
Enhanced Oil Recovery Institute
University of Wyoming
Conclusions
Ultimately CCS is viable only if legislation (international and national) produces a carbon-constrained world. Legal/Regulatory framework under construction. CCS industry will be on scale of oil and gas industry (largest in human history). Expense is uncertain until large scale project completed, but on order of $1 trillion/year to build CCS industry. Possible with current science and technologies.
Future technological advances will reduce cost, improve efficiency and enhance safety. More scientific work needs to be done.
There is technical knowledge and experience within petroleum industry.
Carbon (Dioxide) Emissions and Climate Change
Increase in atmosphere is “linked” to climate changes. There is still no proof of the link.
Carbon Capture and Sequestration
First step is capture of carbon applied to large point sources that currently emit 10,500MtCO2/year (e.g. power stations).
CO2 would be compressed and transported for storage and use.
Large Stationary CO2 Sources
•carbon dioxide sources >0.1 MtCO2/yr•most (75 %) CO2 emissions from fossil fuel combustion/processing (coal-fired power plants are almost 3 wedges)
Four basic systems Post combustion Pre combustion Oxyfuel Industrial
All gas is mostly CO2 plus N2, CO, SO2, etc.
All Methods capture 80-95% of CO2
Carbon Dioxide Capture
Carbon Dioxide Capture
Four basic systems Pre combustion Post combustion Oxyfuel Industrial
Separation stage CO2
Sequestration Targets
Terrestrial Release into the atmosphere for incorporation into biomass
(short term - 10-100’s years) Oceanic
Release into ocean for dissolution and dispersion (medium term – 100-1000’s years)
Geologic Injection into subsurface (long term – 10,000-1,000,000’s
years)
Sequestration Targets
Atmospheric Oceanic Geologic
Sequestration Targets Atmospheric Oceanic Geologic Disposal into deep ocean locations
Much of the ocean is deep enough for CO2 to remain liquid phase(average ocean depth is 12,460 feet)
Largest potential storage capacity(2,000 - 12,000GtCO2 – worldwide)
Storage time 100’s – 1000’s years
Potential ecological damage (pH change)
Models and small scale projects only
Characteristics
Sequestration Targets Atmospheric Oceanic Geologic
Disposal costs are fairly well known
Distance and volume are primary considerations (inverse relationship)
Sequestration Targets Atmospheric Oceanic Geologic
Sequestration Targets Atmospheric Oceanic Geologic
Disposal into subsurface locations
Deep enough to remain supercritical(greater than 2500 feet depth)
Large potential storage capacity(200 - 2,000GtCO2 worldwide)
Storage time 10,000’s – 1,000,000’s years
Potential ecological damage (point source leaks)
40+ years experience in petroleum EOR operations and sour gas disposal
Characteristics
Carbon Dioxide Phase Behavior
Supercritical Fluid is a liquid-like gasGas-like viscosity, fluid-like compressibility and solvent behaviorCO2 above critical T and P(31°C and 73.8 bar or 1085 psi)Density about 50% of water
Combustion product from fossil fuel
GHG Four phases of interest
Carbon StorageGeological Sequestration
want to inject to greater than 800 m depth
CO2 in supercritical state behaves like a fluid with
properties that are mixture of liquid and gas
also stores more in given volume
price to pay in compressing gas
Terrestrial, Oceanic and Geologic P and T conditions.
Ocean conditions allow disposal of liquid CO2
Geologic conditions allow disposal of supercritical CO2
Carbon Dioxide Phase Behavior and Sequestration
need geologic site that will hold CO2 safely for 1000s of years – natural analogs
four possible geologic targets enhanced oil and gas recovery depleted oil and gas fields saline aquifers enhanced CBM recovery
Geological Carbon Sequestration
Geological Carbon Sequestration Leakage Paths
CCS relative costCapture + Pressurization
Cost data from IGPCC 2005
Includes cost of compression to pipeline pressure (1500 psi)
Separation stage CO2
45% difference
CCS relative cost Capture + Pressurization + Transport
Price highly dependent on volume per year.
Includes construction, O&M, design, insurance, right of ways.
for capacities of >5 MtCO2 yr-1 the cost is between 2 and 4 2002US$/tCO2 per 250km for an onshore pipe
Separation stage CO2
37% difference
CCS relative cost Capture + Pressurization + Transport
+ Storage (Oceanic and Geologic)
Oceanic - For transport (ship) distance of 100-500km and injection depths of 3000m
Geologic - For storage in onshore, shallow, highly permeable reservoir with pre-existing infrastructure
Separation stage CO2
31% difference23% difference
CCS relative cost Capture + Pressurization + Transport
+ Storage (Oceanic and Geologic) – EOR Offset
Assuming oil price of $50 bbl.
Without Sequestration Credit (Carbon Tax)
Separation stage CO2
Pilot Projects
Sleipner, Norway (North Sea) Weyburn Project, Saskatchewan (Canada)
Pilot Projects: Sleipner
Sleipner is a North Sea gas field operated by Statoil,
Norway’s largest oil company
produces natural gas for European market
in North Sea, hydrocarbons are produced from platforms
Pilot Projects: Sleipner
special platform, Sleipner T, built to separate CO2 from natural gas supports 20 m (65 ft) tall,
8,000 ton treatment plant plant produces 1 million tons
of CO2 also handles gas piped from
Sleipner West Norway has a carbon tax of
about $50/ton for any CO2 emitted to the atmosphere
to avoid the tax, Statoil has re-injected CO2 underground since production began in 1996
production is from Heimdal Formation 2,500 m (8,200 ft) below
sea level produces natural gas -
mixture of hydrocarbons (methane (CH4), ethane (C2H6), butane (C4H10)), gases (N2, O2, CO2, sulfur compounds, water)
the natural gas at Sleipner has 9 % CO2
Pilot Projects: Sleipner
CO2 injected into Utsira Formation high porosity & permeability
sandstone layer 250 m thick and 800 m
(2,600 ft) below sea bed filled with saline water, not
oil or gas CO2 storage capacity
estimated at 600 billion tons (20 years of world CO2 emissions)
millions tons CO2 stored since 1996
first commercial storage of CO2 in deep, saline aquifer
Pilot Projects: Sleipner
seismic surveys conducted to determine location of CO2
results shown in diagram to left
Optimum conditions for geophysical imaging
Pilot Projects: Sleipner
Conclusions
Ultimately CCS is viable only if legislation (international and national) produces a carbon-constrained world. Legal/Regulatory framework under construction. CCS industry will be on scale of oil and gas industry (largest in human history). Expense is uncertain until large scale project completed, but on order of $1 trillion/year to build CCS industry. Possible with current science and technologies.
Future technological advances will reduce cost, improve efficiency and enhance safety. More scientific work needs to be done.
There is technical knowledge and experience within petroleum industry.