SO 2 /SO 3 /Hg and Corrosion Issue Results From DOE/NETL Existing Plants Oxy-combustion Projects. January 25, 2011 London, United Kingdom

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1 SO 2 /SO 3 /Hg and Corrosion Issue Results From DOE/NETL Existing Plants Oxy-combustion Projects January 25, 2011 London, United Kingdom Jan. 2011

2 National Energy Technology Laboratory Where Energy Challenges Converge and Energy Solutions Emerge Only U.S. government owned & operated DOE national lab Dedicated to energy RD&D, domestic energy resources Fundamental science through technology demonstration Unique industry academia government collaborations Oregon Pennsylvania West Virginia 2 R. Boyle, 02/11/2009

3 DOE/NETL CCS Program Goals By 2020, have available for commercial deployment, technologies and best practices for achieving: 90% CO 2 capture 99%+ storage permanence Pre-combustion Capture (IGCC) < 10% increase in COE 1 Post- and Oxy-combustion Capture < 35% increase in COE 2 *Cost of Electricity includes 50 mile pipeline transport and saline formation storage, 100 years of monitoring 3 1. Impact of Cost Escalation on Power Systems R&D Goals Re-baselining APS, CS & FC GPRA R&D Goals, DOE/NETL July Existing Plants, Emissions & Capture Program Setting Program Goals, U.S. DOE/National Energy Technology Laboratory, Draft Final Report, February 2009

4 Oxy-combustion Projects Overview Combustion/boiler testing 15 MWth T-fired (Alstom) Multi-scale wall fired (B&W, REI, Jupiter, Southern Research) Cyclone (B&W) Coupon corrosion testing NETL ORD Foster Wheeler Flue gas purification systems Air Products Praxair IPR System (NETL ORD & Jupiter) Advanced Oxy-combustion Systems OTM (Praxair) Chemical Looping (Ohio St. & Alstom) 4

5 Pulverized Coal Oxy-combustion Challenges Cryogenic ASUs are capital and energy intensive Existing boiler air infiltration Corrosion and process control Excess O 2 and inerts (N 2, Ar) CO 2 purification cost Project Types 2 nd Gen oxyboiler designs - Adv. Materials and burners Existing boiler retrofits - Air leakage, heat transfer, corrosion, process control Low cost O 2 (membrane) CO 2 purification Co-sequestration Partners: 1. Praxair (O 2 Membrane, CO 2 Purification) 2. Air Products (CO 2 Purification) 3. Jupiter Oxygen (Burners) 4. Alstom (Pilot plant) 5. B&W (Cyclone pilot test) 6. Foster Wheeler (Corrosion) 7. Reaction Engineering Int. (Retrofit) 8. Southern Research Institute (Retrofit) 9. NETL ORD (Modeling, CO 2 Purification) Development Timeline Today: 10 MWe wall-fired test (B&W) 5 MWe T-fired pilot (Alstom) 5 MWe burner pilot (Jupiter) by 2015: 1 st Gen (Cryogenic) demo. 2020: 2 nd Gen demonstration* 5 *O 2 Membrane + USC materials + Adv. Purification + Adv. Compression

6 Boiler Material Development for Oxy-Combustion Foster Wheeler NA, Corp. Investigation of oxy-combustion effects on durability of boiler tube materials Computational fluid dynamic modeling will predict gas compositions Laboratory testing to determine effects on conventional and higheralloy boiler tubes Division Walls OFA Ports Burners Waterwalls Heat Flux (Btu/hr-ft 2 ) 6

7 Oxy-combustion Coupon Studies (Foster Wheeler) Two Nominal 500 MWe Air-Fired Boiler Retrofits Studied Wall-Fired and Tangential-Fired Configurations Compared 2.5% Sulfur Illinois # 6 and 0.3% Sulfur Eagle Butte Coals Us Ill # 6 Wall-Fired Boiler Uses 68% Flue Gas Recycle Flue Gas Mixed with O 2 Yields 28% O 2 by Volume to Boiler Maximum Furnace Wall Heat Flux ~5% Lower than Air-Fired Ill #6 Wall-Fired Boiler Has Highest Furnace Wall Reducing Zones CO H 2 S CO 2 H 2 O Air-Fired 9% 0.14% 11% 8% Oxy-Fired 20% 0.26% 48% 18% Ill #6 Wall-Fired Boiler Gases Selected for Corrosion Testing 7

8 Gas Compositions Test Plan (Foster Wheeler) Gas Waterwall: Oxy-Combustion Waterwall: Air-Fired Superheater/Reheater Gas Gas 20% CO 5% CO 2% CO 1% O 2 5% CO 2% CO 1% O 2 Oxy: 2% O 2 Air: 3% O 2 CO 2 55% 67% 69% 70% CO 2 13% 14% 14% CO 2 69% 14% H 2 O 18% 20% 20% 21% H 2 O 9% 9% 9% H 2 O 21% 9% N 2 7% 8% 8% 8% N 2 73% 74% 76% N 2 8% 74% H 2 S 0.26% 0.07% 0.03% 0.00% H 2 S 0.08% 0.03% 0.00% H 2 S 0.00% 0.00% SO % 0.29% 0.30% 0.32% SO % 0.21% 0.20% SO % 0.20% HCl 0.02% 0.02% 0.02% 0.02% HCl 0.02% 0.02% 0.02% HCl 0.02% 0.02% Total 100% 100% 100% 100% Total 100% 100% 100% Total 100% 100% 8

9 Waterwalls Materials Test Plan (Foster Wheeler) Tube Materials (SA210-A1, SA213-T2, SA213-T11) Weld (T11 to T11) Weld Overlays (309 SS, Inconel 622, VDM Alloy 33) Thermal Sprays 9

10 Superheater/Reheater Tube Materials Materials Test Plan (Foster Wheeler) Conventional (SA213-T22, SA H, SA H) Newer (SA213-T91, NF709, HR3C) Weld (T22 to 304H) Weld Overlays (Inconel 622, VDM Alloy 33, Inconel 72) Deposit materials refreshed every 100 hours Three deposit compositions used for each WW and SH/RH tests (Low, med, high sulfur) 10

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13 Laboratory Fireside Corrosion Exposures Fireside Exposure Tests Determine fireside corrosion ramifications in boilers refitted for oxyfuel combustion. Alloys of interest represent 4 currently used boiler alloys: T22 (for waterwalls) T91 (for waterwalls and superheater/reheater tubes) 347 (for superheater/reheater tubes) 617 (for superheater/reheater tubes and weld overlays) Tasks Initial test to look at ash thickness Exposure tests for 1000 hours with ash refreshment every 250 hours Characterize exposed coupons in terms of corrosion kinetics (primarily by section loss) and corrosion microstructures (by light microscopy, SEM, XRD, and elemental analysis) 13

14 Fireside Corrosion Exposures Waterwalls Oxidative Conditions 450 C Gas Phase (2.5 O 2 ) Air-fired Oxy-fired with CO 2 recycle after FGD Oxy-fired with CO 2 recycle before FGD Ash Phase Base Case: 5Na 2 SO 4, 5K 2 SO 4, 30Fe 2 O 3, 30SiO 2, 30Al 2 O 3 Base case with 10FeS (for 10Fe 2 O 3 ) Base case with 5C (for 2.5SiO 2, 2.5Al 2 O 3 ) Reducing Conditions 450 C Gas Phase (5 CO) Air-fired Oxy-fired with CO 2 recycle after FGD Oxy-fired with CO 2 recycle before FGD Ash Phase Base Case: 5Na 2 SO 4, 5K 2 SO 4, 30Fe 2 O 3, 30SiO 2, 30Al 2 O 3 Base case with 1NaCl (for 0.33Fe 2 O 3, 0.33SiO 2, 0.33Al 2 O 3 ) 14

15 Fireside Corrosion Exposures SH/RH Oxidative Conditions 700 C Gas Phase (2.5 O 2 ) Air-fired Oxy-fired with CO 2 recycle after FGD Oxy-fired with CO 2 recycle before FGD Ash Phase Base Case 5Na 2 SO 4, 5K 2 SO 4, 30Fe 2 O 3, 30SiO 2, 30Al 2 O 3 Fundamental Conditions 650 C Gas Phase Air 70CO 2 +30H 2 O 70CO 2 +30H 2 O+SO 2 Ash Phase A: 50SiO 2-25Al 2 O CaO-12.5Fe 2 O 3 B: 49SiO 2-25Al 2 O CaO- 12.5Fe 2 O 3-1K 2 SO 4 C: A mixture of 67% Deposit A and 33% Carbon D: 49SiO 2-25Al 2 O CaO- 12.5Fe 2 O 3-1MgSO 4 (liquid at 650 C) 15

16 Gas Phase Details Gas Prior Air Prior Oxy SH/RH Air SH/RH Oxy (FGD) SH/RH Oxy (wo FGD) WW Air WW Oxy (FGD) WW Oxy (wo FGD) WW Air WW Oxy (FGD) WW Oxy (wo FGD) Oxidative Conditions Oxidative Conditions Oxidative Conditions Reducing Conditions N Bal 8 8 Bal 8 8 Bal 8 8 CO Bal Bal 14 Bal Bal 14 Bal Bal CO H 2 S H 2 O O SO

17 Fireside Corrosion Prior Experiments Temperature = 675 C (1247 F), ~ Superheater Fireside Gas Linear Velocity = 6 cm/min (not meant to be representative of power plant gas velocities) Synthetic ash mixtures: Ash Mixture Composition, weight % Fe 2 O 3 Na 2 SO 4 K 2 SO 4 Al 2 O 3 SiO 2 Calculated Base/Acid A B No Ash With Ash 17

18 NETL Office of Research & Development Oxy-combustion Efforts Fundamental Properties Combustion and Radiative Property Data Integrated Pollutant Removal Field tests of IPR system Hammond, IN facility Flame characteristics, analyses of ash and slag, GateCycle modeling Corrosion Issues (field tests and laboratory electrochemical tests) Multi-Scale CFD Modeling Advanced coal chemistry, gas mixtures, turbulence, burner geometry, particle models Simulations of REI/University of Utah facilities Integration of water wall fireside corrosion models 18

19 19 Flue Gas Purification

20 Flue Gas Purification for Oxy-Combustion Air Products and Chemicals, Inc. CO 2 may need to be cleaned of acidic impurities such as HCl and SO 2 before being transported by pipeline for sequestration Feasibility of purifying CO 2 from oxy-combustion will be studied 1. SO 2 /NOx removal at 1-30 atmospheres pressure 2. Inert removal at atmospheres pressure 20

21 Rig Constructed Reactor Entire Test Rig 21

22 Range of Flue Gas Tested Low S bituminous oxy-combustion flue gas (WV) Component Vol % CO H 2 O 3-5 O N Ar 4-5 SO 2 NO X (ppm) (ppm) 22

23 700 First Test Run Results Oxyfuel 22 January Condition D SOx Conversion >99% NOx conversion >90% (NOx zero +/- 20 ppmv) 400 ppmv 300 Reactor Outlet Reactor Outlet Reactor Outlet [FLUGAS]NO.SCALED [FLUGAS]SO2.SCALED Reactor Inlet Reactor Inlet Reactor Inlet Reactor Inlet 20:38:24 20:52:48 21:07:12 21:21:36 21:36:00 21:50:24 22:04:48 22:19:12 22:33: Time 23

24 Second Campaign High S bituminous oxy-combustion flue gas (Illinois) Test conducted to evaluate wider performance range SO 2 : ppm NO x : ppm SO 2 /NO x ratio: Reactor performance repeatable Similar capture rates under similar SO x /NO x ratios Hg removal observed at various stages of the process Most removal in pre-scrubber sump 24

25 Flue Gas Purification for Oxy-Combustion Praxair, Inc. Development of flue gas purification for oxycombustion retrofits Targets: 99 percent SO 2 and mercury removal >90 percent NOx removal Separate high and low S coal systems investigated Activated Carbon Bed Sulfuric Acid Process Both use VPSA for addt l CO 2 recovery O 2, N 2, Ar separated and vented 25

26 Preliminary Results SO 2 and NO are oxidized and retained on bed Dilute acid stream produced Performance better at lower Temp, higher Pressure Water aids in SO 2 removal >99% SO 2 and >96% NOx removal at 15 barg Performance maintained after 30 days testing at bench scale 26

27 Techno-Economic Study Results FGD cannot be eliminated identified by design team due to limits on pulverizers and boiler MOC. Alternate configuration to minimize: System removes 44 to 48% of SOx in FGD, rest in Praxair CPU 27

28 To Find Out More About NETL s CO 2 Capture R&D: 28