Demonstration of an Oxyfuel Combustion System Project Update IEAGHG International Oxy-Combustion Workshop 3Rd Workshop, 5Th –6Th March 2008, Japan
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Demonstration of an Oxyfuel Combustion System Project Update IEAGHG International Oxy-Combustion Workshop 3rd Workshop, 5th –6th March 2008, Japan E D Cameron and F D Fitzgerald Date: 6th March 2008 Department: Research & Development Doosan Babcock Energy Limited • Doosan Babcock Energy Limited is a global, multi-specialist, energy services company, operating in the thermal power, nuclear, petrochemical, oil and gas and pharmaceutical industries • Established in 1891 and headquartered in the UK, Doosan Babcock Energy Limited is a leading Original Equipment Manufacturer (OEM) of clean coal power plants and emission control technology • In December 2006, Doosan Heavy Industries and Construction acquired Mitsui Babcock Energy Limited from Mitsui Engineering and Shipbuilding • Doosan Heavy Industries & Construction forms part of the Doosan Group – one of the top 10 conglomerates in Korea - active in engineering, manufacturing and construction of power plants and industrial facilities worldwide • Listed on the Korean Stock Exchange. Largest shareholder is Doosan Corporation Page 1 Doosan Babcock Energy Limited Crawley • Headquartered in Crawley, England, with main facilities in Renfrew, Scotland, and Branch offices throughout the UK • FY 2007 annual order book £771 million (US$1500m approx) • Employees 4,500 worldwide • The only remaining UK based boiler OEM supplier • Strong local aftermarket service capability and Renfrew presence, combined with Engineer-Procure- Construct (EPC) capability • Accreditations include: - ISO9001 : 2000 (Quality) - OHSAS 18001 (Health & Safety) - ISO14001 : 1996 (Environment) • Dedicated to developing market leading technology through investment in people Page 2 Research & Development • Long tradition in R&D and technical support • 250 multi-disciplinary scientists and engineers in purpose built building (2001) • Specialised facilities and equipment • Dedicated R&D Centre established July 07 growing from 50 to 200 staff. R&D Areas: • Boilers • Combustion • Materials and Fuels • Software and Tools • Asset Management Page 3 Oxyfuel Technology - Three Stage Development Programme • To Develop a competitive Oxyfuel firing technology suitable for full plant application post-2010 • A phased approach to the development and demonstration of Oxyfuel technology: Phase 1: Fundamentals and Underpinning Technologies (2006 – 2008) Phase 2: Demonstration of an Oxyfuel Combustion System (2007 – 2009) Phase 3: Reference Designs (2009 – 2010) Page 4 OxyCoal-UK : Phase 1 – Fundamentals and Underpinning Technologies 1) Combustion Fundamentals The tests, supported by TGA, microscopic, and elemental analysis, will establish the devolatilisation, char combustion, and nitrogen partitioning behaviour under air and oxyfuel firing conditions. Drop tube furnace (DTF) characterisation of devolatilization, char burnout and nitrogen partitioning behaviour of six UK and world-trade coals under oxyfuel firing conditions. First coal completed Development of devolatilization and char burnout kinetic parameters from DTF data and application in CFD models of oxyfuel burner and oxyfuel boiler. In progress Explosion bomb characterisation of coal ignition behaviour under oxyfuel firing conditions (same coals as DTF tests). In progress Page 5 OxyCoal-UK : Phase 1 – Fundamentals and Underpinning Technologies 1) Combustion Fundamentals Preliminary test results show the following: – The effect of CO2 on coal devolatilisation was negligible at low temperatures (<1100°C) but became significant at higher temperature (1300°C). This may be indicative of some gasification of the coal. As expected, higher volatile yields were seen for the finer size fraction. – Burnout varied dramatically with temperature (900-1300°C) and residence time (200- 600 ms). Much higher levels of char burnout were achieved with an oxygen level of 10%, compared to 5%. – Chars burned off quicker in CO2 and the 75% CO2 /N2 gas mix than in N2 for both size fractions. However, the improvement in char burnout performance appeared to become less significant with increasing oxygen content. The promoting effect of CO2 on char burnout was greater for the coarse char fraction. Drop Tube Furnace testing and analysis of the other coals in the programme is ongoing at University of Nottingham Page 6 OxyCoal-UK : Phase 1 – Fundamentals and Underpinning Technologies 2) Furnace Design & Operation To investigate the performance of the oxyfuel process and its key impacts on utility plant operation and performance. Pilot scale testing (1MWt) of oxyfuel firing behaviour to two coals (parametric testing, fouling and corrosion behaviour). First coal completed (as presented in Session 2b by B. Goh, E.On) Characterisation of 1MWt test deposit samples by Computer Controlled Scanning Electron Microscope (CCSEM). In progress Laboratory-scale corrosion testing of candidate materials for final Superheater and Reheater sections of boiler under simulated oxyfuel flue gas. First test completed Page 7 OxyCoal-UK : Phase 1 – Fundamentals and Underpinning Technologies 3) Flue Gas Clean-up / Purification A numerical modelling study of AP’s proposed CO2 purification system will be undertaken, with particular emphasis on SOx, NOx, and Hg removal. Conversion of 160kWt NOx Reduction Test Facility (NRTF) to oxyfuel firing configuration. Completed, Commissioning in Progress Parametric testing of Oxyfuel Process. Planned April 2008 Development and testing of novel flue gas clean-up / purification system using simulated and real oxyfuel flue gas. Lab scale testing in Progress (as presented in Session 3 by V. White, Air Products) Pilot scale testing planned April 2008 Page 8 OxyCoal-UK : Phase 1 – Flue Gas Clean-up / Purification Progress Carbon Dioxide Storage Oxygen Storage Oxygen Injection Flue Gas Recycle Fan Page 9 OxyCoal-UK : Phase 1 – Fundamentals and Underpinning Technologies 4) Generic Process Issues A desk-top study, supplemented by test results from the other project activities, will be undertaken to investigate the key process issues associated with an oxyfuel installation on a large utility plant. Assessment of oxyfuel power plant reliability, availability, maintainability, operability and safety. In progress Front End Engineering Design (FEED) Study, including preliminary HAZOP study, for oxyfuel conversion of 90MWt Multi-fuel Burner Test Facility (MBTF) Completed Page 10 OxyCoal-UK : Phase 1 – MBTF FEED Study Results HAZOP Study Key Concerns • Material compatibility in oxygen enriched atmospheres. • Effect of fly ash on oxygen safety. • Leaks of CO2 rich flue gas from Flue Gas Recycle (FGR) ducts. • FGR spray cooler effluent disposal. HAZOP Study Actions • Discussions regarding material compatibility continuing. • FGR off-take located downstream of grit arrester rather than downstream of economiser to reduce FGR fly ash concentration. • Primary FGR and Secondary FGR fans located as close to burner front as possible to minimise length of pressurised FGR duct. • Primary FGR / Transport FGR spray cooler design(s) to minimise effluent acidity and discussions regarding appropriate disposal route. Page 11 OxyCoal-UK : Phase 2 – Demonstration of an Oxyfuel Combustion System Project Aims: • The aim of the project is to demonstrate an oxyfuel combustion system of a type and size (40MWt) applicable to new build and retrofit advanced supercritical oxyfuel plant. • The specific objectives are: – Demonstrate successful performance of a full-scale (40MWt) oxyfuel burner firing at conditions pertinent to the application of an oxyfuel combustion process in a utility power generating plant. – Demonstrate performance of an oxyfuel burner with respect to flame stability, NOx, flame shape and heat transfer characteristics. – Demonstrate operational envelope of an oxyfuel burner with respect to flame stability, turndown, start-up shutdown and the transition between air- and oxyfuel-firing. – Demonstrate safe operation of an oxyfuel combustion process under realistic operating conditions. – Generate sufficient oxyfuel combustion process performance data to inform future investment decisions. – Demonstrate level of technology readiness of the oxyfuel combustion process. Page 12 OxyCoal-UK : Phase 2 – Multi-Fuel Burner Test Facility (MBTF) • 90 MW Thermal Input • Capability to Fire a Wide Range of Fuels – Coals, Bituminous and Low Volatiles • 8% to 40% Volatiles, Dry Ash Free • Up to 35% Ash, As Fired • Up to 20% Inherent Moisture, As Fired – Heavy Fuel Oil – Natural Gas – Orimulsion • Facility usage: – New Burner Development – Contract burner testing – Third party burner testing Page 13 OxyCoal-UK : Phase 2 – Task 1 Task 1: Development of a Purpose-Designed Oxyfuel Demonstration Facility Task 1.1: MBTF Oxyfuel Conversion Design – Planning Approval – Design (Process, Mechanical, Civil and EC&I) – Safety • HAZOP Study • Risk Assessments • Work Instructions • Operating Procedures • Method Statements • COSHH Assessments – Coal Characterisation by University of Nottingham Task 1.2: MBTF Oxyfuel Conversion Installation – Procurement – Fabrication – Installation Page 14 OxyCoal-UK : Phase 2 – Design Basis • Design Coal: Kellingley (UK Bituminous coal, 28%VM) • Design Heat Input: 16, 28, 40, 49 and 70MWt • Flue Gas Recycle Rates: 50, 66 and 80% • Excess Oxygen Range: 2 to 5% v/v (dry basis) Page 15 OxyCoal-UK : Phase 2 – Scope of Supply • Retain air firing capability. • Additional Equipment: – Flue Gas Recycle (FGR) Fans. • Transport FGR. • Primary FGR. • Secondary FGR. – Transport FGR Cooler/Condenser. – Primary FGR Cooler/Condenser.