Hydrogen and Syngas Combustion: Pre-Condition for IGCC and ZEIGCC

Transcription

1 Hydrogen and Syngas Combustion: Pre-Condition for IGCC and ZEIGCC F. Hannemann, B. Koestlin, G. Zimmermann, G. Haupt, Siemens AG Power Generation Power Generation W8IN, G233, CTET

2 Content Introduction Fuel flexibility and IGCC experience of Siemens gas turbine technology Syngas combustion development under the EC Program HEGSA Status and recent activities EC Program ENCAP / Low-NO x hydrogen combustion / challenges, targets and recent activities Outlook W8IN, G233, CTET 2

3 Fuel Flexibility and Integrational Features of Siemens Gas Turbine Applications DOW Plaquemine (USA) Nuon Power Buggenum (NL) Feedstock Coal Coal/biomass Elcogas Puertollano (E) Coal/petroleum coke ISAB Energy Priolo Gargallo (I) Elettra GLT Servola (I) W8IN, G233, CTET 3 Asphalt Gasification DOW Shell Prenflo Texaco Fuel gas temperature 149 C/300 F 300 C/ 572 F 302 C/ 576 F 195 C/ 383 F Blast furnace gas Coke oven gas Natural gas Fuel gas compositions % vol % vol % vol % vol % vol H CO CO N (incl. Ar, O 2) CH Ar H2O O H 2 /CO ratio (vol) Lower heating value 239 BTU/SCF 10.4 MJ/kg 113 BTU/SCF 4.3 MJ/kg 123 BTU/SCF 4.3 MJ/kg 174 BTU/SCF 9.1 MJ/kg 209 BTU/SCF 7.2 MJ/kg Secondary fuel Natural gas Natural gas Natural gas Fuel oil Natural gas Gas turbine 2 x W501D5 1 x V x V x V94.2K V94.2K Air extraction form GT related to ASU 0 % 100 % 100 % 0 % related to compressor 0 % 16 % 18 % 0 % Nitrogen integration 0 % 100 % 100 % 0 % Net power output 208 MW 253 MW 300 MW 521 MW 180 MW Net efficiency (LHV) Not available 43.2 % 45.0 % *) < 40.0 % *) ISO conditons and use of high quality coal

4 Advanced Syngas Combustion - Project Outline EC project NNE5/644/2001 (HEGSA) High Efficient Gas Turbine with Syngas Application Targets Increasing theoretical and technological knowledge of syngas combustion Improving the flexibility of current gas turbine syngas combustion systems Developing an advanced combustion system for annular burner technology operating at higher pressure and temperature using low-btu syngases Scope Specification of requirements - adjusted CFD simulations including generic burner experiments - thermo-acoustic investigations - design studies - prototype design - atmospheric and pressure combustion tests Partners Duration Siemens AG PG (Coordinator, D) 01/ /2005 ANSALDO ENERGIA Spa (I) Universiteit Twente (NL) Deutsches Zentrum für Luft- und Raumfahrt e.v. (D) Enel Produzione SpA (I) NV NUON Energy Trade & Wholesale (NL) W8IN, G233, CTET 4

5 HEGSA / Improvements to 50 Hz Commercial Systems Improved Syngas Burner for Silo-type Vx4.2, Vx4.2K Use of 2 passages for syngas enhances flame stability Optimal adaptation of nozzle design to specific application Syngas 2/ Natural Gas Fuel Oil Syngas 1 Air Air Lean atmospheric blow-off limit tests Enhanced flame stability Syngas start-up capability W8IN, G233, CTET 5

6 HEGSA / Low-NO x Syngas Combustion Concept for SGT5-4000F Application Advanced Syngas Burner for SGT5-4000F Derived from well proven Hybrid Burner technology Adaptation to annular combustion chamber Use of 2 passages for syngas Premix low-no x combustion at elevated firing temperature Manufacturing of new burner design finished Atmospheric combustion test campaign in June at Ansaldo Caldaie/Gioia del Colle Pressurised combustion tests in September at DLR/Cologne Development phase: burner design optimisation by CFD calculation Manufacturing phase: Advanced low NO x syngas burner W8IN, G233, CTET 6

7 Improvements to 60 Hz Commercial Systems SGT6-5000F Syngas Combustion Tests In syngas combustion test campaigns were completed. Results from observations indicate that: Combustor is extremely stable during syngas operation over a wide range of loads and gas compositions NO x target of 25 ppm was achieved with dilution by steam CO emissions were low Additional tests to be completed at full pressure in 2005 Target W501F emissions: 15 ppm NO x on 15% O 2 SGT6-5000F Test Rig SGT6-5000F Syngas Combustor Basket W8IN, G233, CTET 7

8 Pre-Combustion Carbon Capture Project Outline 6 th EU Framework Programme Integrated Project ENCAP Enhanced CO 2 Capture Target: Concepts/technology for CO 2 capture from natural gas and coal fired power plants at 50% capture cost reduction & at least 90% capture rate Partners: Vattenfall AB (leader) and 32 partners (energy and technology providers, RTD institutes) Schedule: 4.5 years (18+36 months), started March 2004 SP1 Process & Power SP3 Oxyfuel Boiler Technolgy SP4 Chemical Looping Combustion SP5 High-Temperature O 2 Generation for Power Cycles Siemens main focus Development of Low-NO x Hydrogen Burner for SGT5-4000F Technology Basic Design of ZEIGCC / ZEIRCC SP6 Novel Pre-Combustion Capture Concepts W8IN, G233, CTET 8

9 Criteria / Challenges for H 2 Combustion in Gas Turbines Clearly higher stoichiometric combustion temperature Smaller volumetric calorific values High flame speed Fuel Properties LHV [MJ/kg] [MJ/m 3 ] Flame speed in air [cm/s] Stoich. comb. temp. [K] CH H CO Density [kg/m 3 STP] Large increase in volumetric fuel flow rates Prevent pre-ignition Care for avoiding flashback Specific heat [kj/kg K] Flammability limits [vol %] Risk of flashback NO x emissions Near-homogeneous mixing of fuel and air within shortest possible time Elimination of any flow separation, stagnation or vortex breakdown High gas flow velocity to compensate increased flame speed to keep the flame lifted off Avoidance of high NO x emission due to high flame temperature W8IN, G233, CTET 9

10 Hydrogen-rich Fuel Gas / Experience and Limits of Existing Syngas Diffusion Burner 300% 250% Risk of Overheating max. H 2 for N 2 Dilution max. H 2 for Steam Dilution laminar flame speed 200% 150% 100% 50% Buggenum Servola Puertollano ISAB Engine References Standard Syngas Combustion System 0% 0% 10% 20% 30% 40% 50% 60% Risk of Lean Blow-off hydrogen content [vol%] W8IN, G233, CTET 10

11 Combustion of H 2 rich fuels with N 2 dilution / Diffusion or DLN Combustion H 2 shifts the maximum of laminar flame speed to rich regions Maximum laminar flame speed represents fuel gas reactivity Diffusion mode: sl H2 /sl CH4 =10 DLN mode: sl H2 /sl CH4 =3 High flashback risk Diffusion mode: Need of much higher dilution DLN challenge: Avoidance of rich zones Risk mitigation for DLN: Increase dilution and gas velocity W8IN, G233, CTET 11 laminar flame spped [cm/s] %H 2 80%H 2 60%H 2 Diffusion mode 40%H 2 CH 4 H2=100% N2=0% H2=80% N2=20% H2=60% N2=40% H2=40% N2=60% Refrence 100% CH4 Tair=400 C Tfuel=15 C p=17bar GRI 3.0 DLN mode air fuel ratio [/]

12 Roadmap for Low-NO x H 2 Burner Development under ENCAP 1. H 2 /N 2 combustion tests to verify stability limits of Standard Siemens Hybrid Burner 2. Development of reduced reaction mechanism for H 2 -rich combustion (SINTEF/DLR) 3. Evolutionary development of low-no x H 2 burners for SGT5-4000F Design CFD Atm. tests pres. tests Development Status: First atmospheric test campaign performed and design modification underway High pressure combustion tests with modified burner planned for June/July 2005 H 2 /N 2 flame Atmospheric test rig at Siemens/Mülheim W8IN, G233, CTET 12

13 Outlook SGT5-4000F Roadmap for Hydrogen-rich Combustion Hydrogen (+ Inert) Air Hydrogen (+ Inert) Air Air Phase 1 (ENCAP): Development of H 2 -Burner Review of Cooling air and hot gas path requirements Phase 2 (BMWA Program COORIVA): Analysis of operational experience (e.g. operational obstacles, effects of corrosion and plugging, degree of GT and overall plant integration ) Phase 3 (project specific) Adaptation of GT for air extraction Design of I&C and GT fuel gas system (e.g. piping, valves, saturation and flushing procedure) W8IN, G233, CTET 13