Advanced Coal Technology 101 National Conference of State Legislators Conference November 1, 2007 Dr. Jeffrey N. Phillips Program Manager Advanced Coal Generation Options
CO 2 Capture in Coal Power Systems 2
Pulverized Coal With CO 2 Capture Integration Issues Fresh Water CO 2 to use or Sequestration Coal Air PC Boiler SCR ESP FGD CO 2 Removal e.g., MEA Flue Gas to Stack Output Penalty: Up to 30% Steam Turbine Fly Ash Gypsum/Waste Amine processes commercially available at relatively small scale; considerable re-engineering and scale-up needed (ultra-low inlet SO 2 and NO 2 also required) Steam extraction for solvent regeneration reduces flow to low-pressure turbine; significant operational impact Maximizing output and efficiency requires optimal heat integration Plot space requirements significant; back-end at existing plants often already crowded by other emission controls Flue Gas from Plant Cleaned Flue Gas to Atmosphere Absorber Tower CO 2 to Cleanup and Compression CO 2 Stripper CO 2 Stripper Reboiler CO 2 Capture = $, Space, Ultra-Low SO 2, and Lots of Energy 3
PC Operating Units w/ CO 2 Capture (Today) Three U.S. small plants in operation today Monoethanolamine (MEA) based CO 2 sold as a product or used Freezing chickens Soda pop, baking soda ~140 $/ton CO 2 300 metric tons recovered per day ~15 MWe power plant equivalent Many pilots planned and in development 5 MW Chilled Ammonia Pilot Many other processes under development AES Cumberland ~ 10 MW CO 2 EPRI (Report 1012796) Assessment of Post- Combustion Carbon Capture Technology PC + CO2 Capture: Technology Exists but Larger Scale Demonstrations & Less Expensive Processes Needed 4
IGCC with CO 2 Removal Steam Sulfur CO 2 to use or sequestration Coal Prep Gasification C + H 2 O = CO + H 2 Gas Cooling Shift CO+ H 2 O = CO 2 + H 2 Sulfur and CO 2 Removal O 2 N 2 Hydrogen Air Separation Unit Gas Turbine Air BFW Air Steam HRSG BFW Steam Turbine 5
Coal Gasification Plants w/co 2 Capture (Today) IGCC and CO 2 removal offered commercially Have not operated in an integrated manner Three U.S. non-power facilities and many plants in China recover CO 2 Coffeyville Eastman Great Plains The Great Plains Synfuels Plant http://www.dakotagas.com/companyinfo/index.html Great Plains recovered CO 2 used for EOR 2.7 million tons CO 2 per year ~340 MWe if it were an IGCC IGCC + CO 2 Capture Ready for Demonstration but need to decrease costs Weyburn Pipeline http://www.ptrc.ca/access/desktopdefault.aspx 6
Oxy-Combustion Capture Status Source: Vattenfall No Commercial Power Plants use Oxy-Combustion today, but: Several pilot scale (~1 MW) test units operating Vattenfall 30 MW th pilot plant announced B&W 30 MW th test facility in Ohio 7
CO 2 Capture Can Be Done Today, But. It would increase the cost of electric power from coal significantly EPRI s current estimates Cost of power from a pulverized coal plant with post-combustion capture would be 60-80% higher Cost of power from an IGCC with pre-combustion capture would be 40-50% higher (but IGCCs start out with a higher cost, so won t necessarily be cheapest option with CCS) Cost of oxy-combustion more difficult to estimate with certainty at this stage of development but overall cost of power probably similar to PC + post combustion capture Luckily, EPRI also estimates that with a concerted RD&D effort, the cost impact of CCS could decrease dramatically 8
EPRI PC and IGCC Cost of Electricity With and Without CO 2 Capture (Illinois #6 Coal) (All IGCC and CCS cases have +10% TPC Contingency for FOAK) 130 30-Yr levelized COE, $/MWh (Constant 2006$). 120 110 100 90 80 70 60 50 No Capture Retrofit Capture New Capture COE Includes $10/tonne for CO 2 Transportation and Sequestration 40 Supercritical PC GE Radiant Quench GE Total Quench Shell Gas Quench E-Gas FSQ 9
EPRI PC and IGCC Cost of Electricity With and Without CO 2 Capture (PRB Coal) (All IGCC and CCS cases have +10% Contingency for FOAK) 30-Yr levelized COE, $/MWh (Constant 2006$). 130 120 110 100 90 80 70 60 50 No Capture Retrofit Capture New Capture COE Includes $10/tonne for CO 2 Transportation and Sequestration 40 Supercritical PC Ultrasupercritical PC Shell Gas Quench E-Gas FSQ 10
USC PC RD&D Augmentation Plan Expected Benefits Case: Pittsburgh #8 coal, 90% availability, 90% CO 2 capture Relative $/kw Total Plant Cost (2005 = 100%) 110 Near Mid-Term: Upgrade steam conditions to 100 4200/1110/1150 90 80 Near-Term: Upgrade solvent from MEA to MHI KS-1 (or equivalent) Upgrade steam conditions from 3500/1050/1050 to 3615/1100/1100 Mid-Term: Upgrade steam conditions to 5000/1300/1300, and then to 5000/1400/1400/1400 Plant Net Efficiency (HHV Basis) 40 Long-Term: Upgrade solvent 70 to ammonium 32 bicarbonate (or equivalent) 60 2005 2010 2015 2020 30 2025 38 36 34 11
IGCC Long-Term RD&D Plan Expected Benefits Case: Slurry-fed gasifier, U.S. bituminous coal, 90% availability, 90% CO 2 capture Relative Plant Cost ($/kw, 2005 = 100%) 110 100 90 80 70 60 Near-Term Add SCR Eliminate spare gasifier F-class to G-class gas turbines Improved Hg detection Mid-Term Ion transfer membrane oxygen G-class to H-class gas turbines Supercritical HRSG Dry ultra-low-no X combustors Long-Term Membrane separation Warm gas cleanup CO 2 -coal slurry Longest-Term Fuel cell hybrids 2005 2010 2015 2020 2025 2030 40 38 36 34 32 30 Plant Net Efficiency (HHV Basis) 12
What could we do with CO 2? Put it in the bottom of the ocean Significant environmental uncertainties Make a solid out of it Large amounts of solids and high energy penalty Utilize it No use for such a large amount Geologic Storage May be best solution but has challenges 13
CO 2 Storage Main Focus is Injection Into Geological Formations Saline reservoirs 100 s of years capacity Little experience Economical, but lesser capacity options Depleted oil & gas reservoirs/enhanced oil recovery Unmineable coal beds/enhanced coal-bed methane recovery Deep ocean injection not acceptable today Mineralization a dream Courtesy of Peter Cook, CO2CRC 14
How Does Saline Reservoir Storage Work? Inject into deep, high salinity reservoirs No impact on drinking water Limited data Few wells penetrate reservoirs Large volume potential for storage Order of magnitude larger than oil Reasonably well distributed across country 15
CO 2 Transportation Issues The technology (compressors and pipelines) is relatively straightforward but there are some questions: What impurities are allowable? Must it meet current commercial pipeline specifications? Liability transfers? 16
U.S. Has Experience With CO 2 Pipelines for EOR. Need to Show It s Applicable or Can Manage Differences Coal Gasification LeBarge McElmo Dome Sheep Mountain St. John Dome Ammonia Plant Bravo Dome Jackson Dome CO 2 Sources Natural Gas Plants Industrial Pipelines 2,500+ Miles of CO 2 Pipe in US Today 350,000 for Natural Gas 17
Socio-political Concerns - Risk & Acceptability Leakage risks Public acceptance Permitting Legal/liability Concerns Environmental impacts Need everyone, not just engineers, to resolve these issues 18
Regulatory Risk Uncertainty Who has jurisdiction over saline reservoirs? States or US EPA? Who owns saline reservoirs CO2 absorptive capability? What impurities are permitted and how much? Who is responsible if there is a leak of CO 2 back into the atmosphere? Source: USEPA 19
What s Next What s Needed for Coal? Acceleration of the Industry efforts worldwide in addition to governmental efforts Cost reductions and efficiency improvements for capture systems Large scale testing of storage of CO 2 in deep saline reservoirs: >1 million tons of CO 2 /year at multiple sites Eliminate permitting uncertainty 20
Timeline for CO 2 Storage & Post-combustion Capture Demos to Meet 2020 Target Start 1 st 20+MW Injection Demo Accelerate DOE schedule Commercial availability of postcombustion CO 2 capture & storage 2005 2010 2015 2020 1 st demo AEP? Design, permit, build Inject (4 yr) Monitor 2 nd 5 th demos Source: DOE Roadmap (modified) 21
Background slides
Combustion & Gasification Products 23
1000ºC 24
1000ºC 25
1400ºC 26
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Combustion vs Gasification Combustion SO 2 & SO 3 is scrubbed out of stack gas reacted with lime to form gypsum NOx controlled with low NOx burners and catalytic conversion (SCR) Flyash removed via ESP or bag filters Hg can be removed by contacting flue gas with activated carbon Gasification H 2 S & COS are easily removed from syngas and converted to solid sulfur or sulfuric acid NH 3 washes out of gas with water, thermal NOx controlled by diluent injection in GT, optional SCR for deeper NOx removal Ash is converted to glassy slag which is inert and usable >90% of Hg removed by passing high pressure syngas thru activated carbon bed 28
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What can you do with coal gasification? Produce Electricity In a Gas Turbine-based Combined Cycle power plant Emissions approaching that of a natural gas fired power plant Make Fuels Sasol has been making gasoline from coal since the 1950s in Republic of South Africa Dakota Gasification has been making synthetic natural gas from lignite since the 1980s Make Chemicals Eastman Chemicals has been doing this since 1980s Make Fertilizer Coffeyville Resources in Kansas makes ammonia-based fertilizer from petroleum coke Make Hydrogen FutureGen project will set the stage for production of H 2 from coal 30
Steam Cycles vs Combined Cycles Steam Cycles have a boiler a steam turbine Referred to as Rankine cycle, fossil boiler, fossil steam plant, conventional coal plant Combined Cycles (the CC in IGCC) have a Gas Turbine a heat recovery steam generator (HRSG) a steam turbine 31
Conventional Coal Plant 12 MW 39 % Efficiency (HHV basis) 88 MW 2.5 MW own use 100 MW 41.5 MW 39 MW 46.5 MW 32
Gas Turbine simple cycle 100 MW 65 MW 35 MW 35% Efficiency (HHV basis) 33
Combined Cycle 27 MW 100 MW 38 MW 65 MW Fuel 17 MW 35 MW 21 MW to condenser 17 + 35 = 52 MW 52% Efficiency! (HHV basis) 34
Combined Cycle Photo source: Siemens 35
100MW Net Coal to Power: 28 + 20 9 = 39% (HHV basis) 9MW 20MW 27 MW 19MW 47MW 36 15MW 79MW 51MW 28MW IGCC schematic from US DOE
CO 2 Capture & Storage (CCS) is Needed to Stabilize CO 2 Emissions from US Power Plants 37
New Technology Deployment Curve for Coal Research Development Demonstration Deployment Mature Technology Advanced USCPC Plants 1400 F 1150 F+ CO 2 Capture Anticipated Cost of Full-Scale Application Oxyfuel CO 2 Storage IGCC Plants USCPC Plants 1150 F+ 1100 F <1100 F 1050 F SCPC Plants Not All Technologies at the Same Level of Maturity 38 Time