WRITECoal Gasification of Low- Rank Coals for Improved Advanced Clean Coal Gasifier / IGCC Design

Transcription

1 WRITECoal Gasification of Low- Rank Coals for Improved Advanced Clean Coal Gasifier / IGCC Design Alan E. Bland, Jesse Newcomer and Tengyan Zhang- Western Research Institute Kumar M. Sellakumar - Etaa Energy Michael Roberts- Gas Technology Institute Robert Keeth - URS-Energy and Construction

2 Disclaimer This presentation was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed or represents that its use would not infringe on privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. 2

3 Presentation Outline Background / Issues of Gasification Deployment in Wyoming WRITECoal Process Description and Performance Gasification Tests Results WRITECoal IGCC Modeling Next Steps

4 Project Participants & Objectives Participants: Western Research Institute Etaa Energy, Inc. Gas Technology Institute URS-Energy and Construction Co-Sponsors: UW School of Energy Resources / State of WY Clean Coal Tech. Program U. S. Department of Energy, National Energy Technology Laboratory Industry/Others Objectives: Develop an advanced gasifier design that allows PRB coal-based technologies to compete with other carbon capture ready technologies to produce power as well as chemicals, by developing a fully integrated WRITECoal gasification process with optimized gasifier operation, postgasifier syngas cleanup, water gas shift, and possible CO 2 recycle. 1

5 Impact of IGCC Siting Low Altitude High Altitude Relative LCOE Relative LCOE SCPC Shell IGCC 90% CO 2 Capture SCPC Shell IGCC At Low Altitude IGCC has an Advantage of 17% - PRB Coal (EPRI, 2007) At High Altitude, Supercritical PC has an Advantage of 22% - PRB Coal (DOE, 2009) 10

6 Coal Rank vs Heat Rate and Capital Coal Rank Impacts IGCC Capital Costs by Over 30%. As such, WRITECoal Technology Applied to PRB Coal Can Help Reduce IGCC Capital Costs. Relative Heat Rate or Capital Cost ICGG Heat Rate (E-Gas) 1.30 IGCC Capital Cost (E-Gas) Illinois # TX Lignite WY PRB 1.05 Pittsburgh # ,000 6,000 7,000 8,000 9,000 10,000 11,000 12,000 13,000 14,000 15,000 Coal Heating Value, Btu/lb HHV Correlation Between Coal Rank and IGCC Heat Rate and Cost (Modified from Booras, 2008). 15

7 Typical WRITECoal IGCC Schematic WRITECoal Process Island Water for Plant Uses Coal Gasifier Processed Coal Gas Cooler Dust Collector Water/Steam *Water/Steam Water Gas Shift Tail Gas Recycle Syngas Cooling & Hg Removal Sulfur Sulfur Recovery Acid Gas /CO 2 Removal Water/Steam Air O 2 ASU ST S S GT Gas Recycle N 2 CO 2 To Storage HRSG 19

8 WRITECoal Mercury Emissions Control Pilot testing of novel mercury control technology: The Western Research Institute is developing and evaluating the removal of mercury from coal prior to combustion. The institute developed a two-step process that involves first evaporating moisture in the coal and then heating the coal with inert gas. Precombustion mercury removal technology has been successful in removing 75 percent of mercury from subbituminous coal and 60 percent of mercury from lignite coal, but the technology has encountered difficulty when used with bituminous coal. By removing up to 75 percent of mercury before combustion, less mercury remains in the exhaust gas for removal by pollution control devices. In addition, pre-combustion technology has other benefits: (1) removing the moisture from the coal increases the heat content of the coal for combustion purposes, which may reduce the amount of coal burned by the plant and increase efficiency by about 3 percent; (2) this process also helps to remove other trace metals; (3) the water that is removed from the coal during pre-combustion treatment can be recovered and re-used in plant operations. According to DOE, Western Research Institute testing has also shown that, for some coals, the amount of time the coal is exposed to heat affects the amount of mercury removed. For example, an increase of 8 minutes of residence time resulted in the removal of nearly 80 percent of mercury before combustion. 2

9 WRITECoal Process WRITECoal Process Increases plant efficiency by 3-5%. Reduces coal feed or Increases plant power output by up to 5%. Removes moisture from the coal, allowing recovery for plant use. Removes trace metals and other volatile species. Staged retrofit deployment for carbon capture enhances financing. Parameter Wyoming PRB Coal Proximate Analysis (wt%) Raw WRITECoal Product Total Moisture, as received 28.4 <1.0 Ash, dry basis Volatile Matter, dry basis Fixed Carbon, dry basis Heating Value (Btu/lb) 8,716 11,188 Mercury (ppm), dry basis

10 Coal Type WRITECoal Gasification Results Gasification Conditions Devolatilization Carbon Conversion, % Char Reaction Total Char Residence Time, min. Raw PRB Syngas/Steam WRITECoal Syngas/Steam Raw PRB-AM Syngas/Steam AM Ash Modified Syngas/Steam 30% H 2 ; 12% CO; 8% CO 2 ; 50% H 2 O WRITECoal product has high carbon conversion during devolatilization and its char is highly reactive. 3

11 Gasifier Results 356 Syngas High Heating Value (Btu/scf) Coal Raw/Treated R R T T Steam Yes/No Yes No Yes No Oxygen-Blown Gasifier WRITECoal yields higher Btu syngas and syngas volume, thereby lowering gasifier size and/or ability to handle more gas recycle.

12 Gasifier Results CO+H Other gases * Data shown are percentage of gases by volume Coal Raw/Treated R R T T Steam Yes/No Yes No Yes No Oxygen-Blown Gasifier WRITECoal yields highest concentration of CO+H 2

13 Gasifier Results CO Coal Raw/Treated R R T T Steam Yes/No Yes No Yes No Oxygen-Blown Gasifier WRITECoal yields lowest concentration of CO 2

14 Gasifier Results Cold gas conversion efficiency, % Coal Raw/Treated R R T T Steam Yes/No Yes No Yes No Oxygen-Blown Gasifier WRITECoal has higher cold gas conversion efficiency

15 WRITECoal IGCC Modeling Without CCS With CCS With CCS Est. From Modeling Studies Efficiency (%) Based on HHV Baseline Sub C PC 1 (1) MEA for capture case Average IGCC U-GAS IGCC 35.4 WRITECoal IGCC Efficiency of the WRITECoal IGCC Compared to Other Power Generation Options (Modified from Ciferno, 2007 and Nexant, 2006). 6

16 IGCC Techno-Economic Study Option Raw Coal WRITECoal Key Gasification Features A X Standard IGCC design without CO 2 capture B X Standard IGCC with CO 2 capture C X Integrated WRITECoal IGCC design with CO 2 capture COE and capital costs of the three options shown above are being developed and the benefits of WRITECoal integration to IGCC and CO 2 capture quantified. 12

17 WRITECoal Gasification Process* for Low-Rank Coal for Improved IGCC with Carbon Capture: Phase II Pilot-Scale Demonstration Objective: To demonstrate the WRITECoal gasification process at sub-pilot and 1 MWth pilot-scale and to assess the process for IGCC, IGFC, and hydrogen separation applications Participants: Western Research Institute Energy and Environmental Research Center Etaa Energy, Inc. Fuel Cell Energy Gas Technology Institute URS-Energy and Construction Co-Sponsors: State of Wyoming Clean Coal Technology Program Lignite Research Council North Dakota Industrial Commission U. S. Department of Energy through National Center for Hydrogen Industry/Others *Patent Pending Next Steps 1

18 Phase II Study Phase II effort will confirm the performance of WRITECoal gasifier from Phase I results and will investigate ND lignite and PRB coals at 1-2 MWthscale, and evaluate, test and model impact on IGCC, IGFC, and hydrogen production. Test Facilities: Gas Technology Institute s U-GAS gasifier EERC s 1 MWth transport gasifier WRI s WRITECoal 1-2 MWth pilot Photograph of the WRI s Mobile 1-2 MWth Pilot-scale WRITECoal Unit 7

19 Phase II Pilot Units Schematic of the TRDU at EERC (2009) Photograph of the GTI U-Gas test facility (GTI, 2009) Gasification Test Facilities to be Used in Proposed Phase II Program. 8

20 Phase III. Next Step Toward Commercialization The next step in the commercialization of the technology for PRB coal-fired plants is real-world pilot-scale demonstration such as at GTI s Flex-Fuel. Phase III proposed demonstration in GTI s FlexFuel 5 MWth U-GAS Pilot-scale Facility 1a 1b 1c Advanced Gasification Test facility, 2. Flex-Fuel Test Facility, 3. Morphysorb, 4. SulfaTreat, and 5. High pressure Oxygen and Nitrogen Supply

21 Summary WRITECoal Gasification / IGCC Testing: Testing at lab- and benchscale shows that the technology results in efficiency improvements, unique syngas composition and recovered water / steam being available for plant use. WRITECoal Gasification / IGCC Modeling: Modeling shows a net efficiency gain of 3-4% for low-temperature, non-slagging gasification / IGCC technologies with WRITECoal IGCC integration and 90% carbon capture compared to IGCC cycles without WRITECoal integration / modifications. Cost and Deployment Opportunities: The WRITECoal Gasification / IGCC process can be deployed with nearly all of the commercially available gasification systems and can have positive cost impacts by lowering the capital and operating costs and thus lowering the COE. WRI expects to have a 5 MWth demonstration of the technology upon completion of the Phase II pilot-scale testing that will further define the commercial deployment opportunities and cost benefits. 18

22 Acknowledgements Special thanks to the following companies/organizations for their participation and financial support for Phase I and II: University of Wyoming School of Energy Resources/State of Wyoming Clean Coal Technology Program Basin Electric Power Cooperative Etaa Energy Gas Technology Institute North Dakota Industrial Commission / Lignite Research Council Fuel Cell Energy Montana-Dakota Utilities URS Energy and Construction Univ. North Dakota Energy and Environmental Research Center U.S. DOE Center for Hydrogen Production U.S Department of Energy National Energy Technology Laboratory Under Cooperative Agreement DE-FC26-08NT

23 Acknowledgements (Continued) Funding for this research project was provided by the Wyoming State Legislature. The state and federal awarding agencies reserve a royalty-free, nonexclusive, and irrevocable license to reproduce, publish or otherwise use, and to authorize others to use, for state and federal government purposes: - The copyright in any work developed under a grant, subgrant, or contract under a grant or sub-grant, and - Any right of copyright to which a grantee, sub-grantee or a contractor purchases ownership with grant support.

24 For More Information, Contact: Alan E. Bland Western Research Institute 365 North 9 th Street Laramie, WY (307) abland@uwyo.edu 24