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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.
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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)
Carbon Dioxide Capture 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 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 Characteristics 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
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 Characteristics 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
Carbon Dioxide Phase Behavior • Combustion product from fossil fuel • GHG • Four phases of interest • Supercritical Fluid is a liquid-like gas • Gas-like viscosity, fluid-like compressibility and solvent behavior • CO2 above critical T and P (31°C and 73.8 bar or 1085 psi) • Density about 50% of water
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
Carbon Dioxide Phase Behavior and Sequestration • Terrestrial, Oceanic and Geologic P and T conditions. • Ocean conditions allow disposal of liquid CO2 • Geologic conditions allow disposal of supercritical CO2
Geological Carbon 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
CCS relative costCapture + Pressurization 45% difference • Cost data from IGPCC 2005 • Includes cost of compression to pipeline pressure (1500 psi) Separation stage CO2
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 37% difference Separation stage CO2
CCS relative cost Capture + Pressurization + Transport + Storage (Oceanic and Geologic) 23% difference • 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 31% difference Separation stage CO2
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
Pilot Projects: Sleipner • 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) • millionstons 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
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.