PRECOMBUSTION TECHNOLOGY for Coal Fired Power Plant

Transcription

1 IEA Greenhouse Gas R&D Programme 2013 Summer School. Nottingham, UK PRECOMBUSTION TECHNOLOGY for Coal Fired Power Plant MONICA LUPION Visiting Research Scientist MIT Energy Initiative

2 MITEI's Research Program MIT President called in 2005 for a renewed Institute commitment to energy-related research and education MITEI annual research volume of over $30 million (USD) About 800 research projects since 2007, around 400 researchers Spread across 22 of the 24 MIT academic departments, and 24 labs and centres The MITEI interdisciplinary research program focuses on: Innovative technologies and underlying policy analysis that will improve conventional energy systems Transformational technologies to develop alternative energy sources Global systems through multidisciplinary systems approach that integrates policy design and technology development Tools to enable innovation, transformation and simulation of global energy systems through strategic basic research 2

3 CC&ST Program CC&ST Program internationally recognized as a world leader in CCS Initiated in 1989 Carbon Sequestration Initiative (July, 2000) Key Activities Research Annual Forum Outreach More info 3

4 Presentation Outline Introduction Gasification Technology Overview Types of Gasifiers Combustion versus Gasification IGCC IGCC Overview IGCC Comparison IGCC with CO2 Capture General Overview Experiences Concluding remarks 4

5 Introduction Precombustion Technology 5

6 Introduction CO2 3-15% CO2 40% Adapted from EPRI 2007 CO2>95% 6

7 Introduction CO2 3-15% CO2 40% Adapted from EPRI 2007 NO SILVER BULLETS!! CO2>95% 7

8 Presentation Outline Introduction Gasification Technology Overview Types of Gasifiers Combustion versus Gasification IGCC IGCC Overview IGCC Comparison IGCC with CO2 Capture General Overview Experiences Concluding remarks 8

9 Gasification Technology Overview 9

10 A bit of technology: Gasification A partial oxidation process that can convert any hydrocarbon into hydrogen and carbon monoxide (synthesis gas or SYNGAS) (CH) n + O2 H2 + CO For example: 2 CH4 + O2 4H2 + 2 CO [ Methane] [Oxygen] [Hydrogen] [Carbon Monoxide] Process Conditions: ºC, bar 10

11 A bit of technology: Gasification So what can we do with CO and H 2? 11

12 A bit of technology: Gasification PC Boiler DeNO X Dedusting DeSO X AIR Ash Dedusting DeSO X AIR O 2 H 2 O CYCLE (GT+ST) Gasifier Ash DeNO X Fisher-Trops Metanol Chemicals Transport fuels CFB Boiler Dedusting Bed material Absorbent AIR Steam Turbine Ash + Absorbent ST 12

13 A bit of technology: Gasification Severe thermo-chemical operating conditions Chlorine Nitrogen H2O Carbon monoxide Hydrogen Carbon dioxide Mineral matter Water Ash Ammonia Sulphur Carbon Hydrogen Hydrosulfuric Acid, H2S Hydrochloric Acid, HCl O2 REACTANTS PRODUCTS 13

14 Gasification Types of Gasifiers 14

15 Type of gasifiers C % Resident time Pressure (bar) Temperature ( C) Particle Size Moving Bed (LURGI) /2 h >10 mm Fluidized Bed (WINKLER) 70 3/4 h mm Entrained Flow (KOPPERS- TOTZEK) Few seconds % 200 mesh x down (dry) 15

16 Gasification Combustion vs Gasification 16

17 Combustion vs Gasificacion Combustion SO 2 & SO 3 is scrubbed out of stack gas reacted with limestone to form gypsum NO X controlled with low NO X burners and catalytic conversion (SCR) Fly ash removed via ESP or bag filters Hg can be removed by contacting flue gas with activated carbon Gasification H 2 S & COS easily removed from syngas and converted to solid sulfur or sulfuric acid NH 3 washes out of gas with water, thermal NO X controlled by diluent injection, optional SCR for deeper NO X removal Ash converted to glassy slag which is inert and usable >90% of Hg removed by passing high pressure syngas thru activated carbon bed 17

18 Presentation Outline Introduction Gasification Technology Overview Types of Gasifiers Combustion versus Gasification IGCC IGCC Overview IGCC Comparison IGCC with CO2 Capture General Overview Experiences Concluding remarks 18

19 IGCC Overview Stack Fuel Gasifier Dedusting DeSO X HEAT RECOVERY STEAM TURBINE 40% GAS TURBINE 60% O 2 Bottom Ash Ash S Air Combined Cycle ASU N 2 Air 19

20 IGCC vs Conventional Coal PS Clean-up of fuel prior to power generation Solid waste Less Volume: IGCC produce about half the solid wastes of conventional coal plants Better Form: IGCC solid wastes less likely to leach toxic metals than fly ash from conventional coal plants because IGCC ash melts and is vitrified (encased in a glass-like substance) Water Use Less Water: IGCC units use 20%-50% less water than conventional coal plants and can utilize dry cooling to minimize water use 20

21 IGCC vs Conventional Coal PS Environmental Technology => Greatest potential for future Lowest NO X, SO X, particulate matter and lower hazardous air pollutants Hg and CO 2 removal Lower water usage, lower solids production Sulfur and non-leachable slag by-products CO 2 under pressure takes less energy to remove than from PC flue gas (Gas volume is <1% of flue gas from same MW size PC) Proven polygeneration flexibility Power, hydrogen, steam, chemicals, zero-sulfur diesel Practical opportunity to retrofit carbon capture equipment 21

22 Presentation Outline Introduction Gasification Technology Overview Types of Gasifiers Combustion versus Gasification IGCC IGCC Overview IGCC Comparison IGCC with CO2 Capture General Overview Experiences Concluding remarks 22

23 IGCC with CO2 capture Source: VATTENFALL 23

24 IGCC with CO2 capture Source: VATTENFALL 24

25 IGCC with CO2 capture Source: VATTENFALL 25

26 IGCC with CO2 capture Source: VATTENFALL 26

27 IGCC with CO2 capture Source: VATTENFALL 27

28 IGCC with CO2 capture CO-shift: CO+H 2 O=CO 2 +H 2 Stack Gasifier CO 2 Removal HEAT RECOVERY STEAM TURBINE 40% Fuel O 2 Dedusting CO shift DeSO X GAS TURBINE 60% ASU Bottom Ash Ash S Air Combined Cycle N 2 Air 28

29 IGCC with CO 2 capture Experiences 29

30 PSE CO2 project Company Location Feed gas Size ELCOGAS, S.A (Spanish utility) Puertollano (Spain). Integrated in the Puertollano IGCC plant Coal gas at bar 14 MWt (2% of total coal gas produced in the IGCC plant) Technology Budget 14.3 M Commissioning 2011 Pre-combustion Carbon Capture (90%). No Storage foreseen 30

31 IGCC with CO2 capture Puertollano IGCC power plant and pilot plant location PRENFLO Gasifier Coal preparation ASU Pilot plant general view New CO 2 capture pilot plant Sulphur Recovery Combined Cycle IGCC power plant general view 31 31

32 Don Valley Selected EEPR program (180 M ) Precombustion Technology (IGCC), 4.5 MtCO 2 / a CO 2 : EOR in North Sea Area (offshore) Source: PowerFuel 32

33 Summary and Concluding remarks 33

34 Summary and Concluding Remarks One of the main elements is the gasification of the fuel feedstock to produce SYNGAS Pre-combustion capture process is not a new concept Primarily based on production of syngas, separating the CO2 and using the decarbonised gaseous fuel for the GT Gasification technologies could produce a waste gas stream, which has high concentration of CO 2 This offers an opportunity to capture CO 2 at relatively low cost 34

35 Summary and Concluding Remarks Advantages High CO2 concentration and high overall pressure Lower energy consumption for CO2 separation as compared to post-combustion capture Compact equipment Proven CO2 separation technology Possibility of co-production of hydrogen Disadvantages IGCC is unfamiliar technology for power generators Existing coal fired plants have low availability IGCC without CO2 capture has generally higher costs than pulverised coal combustion 35

36 Thank you!!! Monica Lupion MIT Energy Initiative 36