Large Engines Competence Center

Transcription

1 Large Engines Competence Center CHALLENGES FOR LARGE GAS ENGINES IN FUTURE ENERGY SYSTEMS Wibke Tritthart / Jan Zelenka / Gernot Kammel / Gerhard Pirker

2 Displacement [l/cyl.] Large Engines Large Engines Low speed Medium speed High speed WÄRTSILÄ RT flex 96c MSC OSCAR Length app. 400 m > Container MAN 50/61DF 100 GE J GE J616 Diesel 2 l/cylinder Engine Speed [rpm] MTU 2000

3 Large engines Fuels and applications Diesel HFO (heavy fuel oil) Gas and dual fuel Source: Basshuysen, Springer, Power generation Mechanical drives Marine

4 Gas engine potentials In renewable energy systems Industry Fossil Resources Biomass Wind Solar Waste Gases BFG Flare Gas Natural Gas Gasification PowerToGas Natur al Gas Biogas H 2 Renewable Gases CH 4 H 2 CO2 Methanation Gas Grid Engine Electric Grid

5 World natural gas market Natural gas supplies 22% of the energy used worldwide. Natural gas demand will grow helped by low prices, ample supply, and its role in reducing air pollution and other emissions. The natural gas market is becoming more globalized, driven by the availability of shale gas and the rising supplies of liquefied natural gas (LNG). Source: IEA Natural Gas Information Overview 2017 World natural gas demand (selected countries)

6 Gas quality considerations Gas market liberalisation: Europe European Gas Regulatory Forum ( Madrid Forum ) (1999) European Association of Streamlining of Energy Exchange (EASEE) (2002) Common Business Practice CBP 2005 Hamonization of Natural Gas quality EU Mandate M/400 to CEN (2007) CEN/TC 234 EN 16726:2013, EN 16726:2015

7 Gas quality considerations Gas market in US Federal Energy Regulatory Commission (FERC) regulates interstate transmission of Natural Gas Order 636: unbundling of transportation, storage and sales for pipeline&distribution companies Intrastrate pipelines (and also local distribution pipelines) engaged in the transportation of natural gas must have an approved tariff on file. Problem of flaring

8 NASA Earth Observatory's Suomi Satellite captured the night time glow from hundreds of flares from rigs drilled into the Bakken shale oil formation of North Dakota, creating a light show the size of metropolitan Boston. Bakken Shale Chicago Boston 5% of global gas production wasted = 900 million tons/year of CO 2 emissions!!!

9 Variation of Natural Gas quality Gas engine relavant parameters Wobbe Index specific gravity) energy output of the fuel gas (V c higher heating value, G s EASEE / EN 16726:2013 and countries US

10 Variation of Natural Gas quality Gas engine relavant parameters Methane number: determined to characterize the tendency of the gas (or gas mixture) to cause a knocking combustion in an IC engine. MN of methane = 100, MN of H 2 = 0 MN limit (in EN 16726:2015) = 65 cylinder pressure p [bar] TDC TDC TDC crank angle [ KW] crank angle [ KW] crank angle [ KW] Cylinder a) pressure for b) regular and knocking c) combustion Shockwaves up to 600 m/s > /06/21/common-engineknock-causes/

11 Gas quality studies Calculation acc. to EN 16726:2013 Starting from a typical biogas / landfill gas composition Component Symbol Units Biogas Landfill gas Methane CH4 mol % Oxygen O2 mol % - 1 Nitrogen N2 mol % - 14 Carbon dioxide CO2 mol % Methane Number MZ Limits of mixing with Russian NG for WI and density Units EN EASEE Landfill gas mol % Biogas (aae digester) mol % Hydrogen mol % 5 5 WI WI density

12 Gas quality studies Wobbe Index and Methane number MN as function of H/C-ratio Admixture of 25%-20%-15%- 10%-5%-0% Landfill gas (left) and Biogas (right ) to Russian NG red dot =pure CH 4 Upper fig.: Wobbe Index limit Lower fig.: MN

13 Further considerations Methane number calculation based on H/C-ratio, on EN app.a, are not sufficient. LEC developped an own method LEC-GPN (Gas Performance Number) [1] Problems of Biogas/Landfill gas are posed by other contaminants: H 2 S: Corrosion H 2 S + 3/2 O 2 H 2 O + SO 2 H 2 SO 4 H 2 SO 3 Sulphurous/sulphuric acid Siloxanes [1] Wimmer et al.: LEC-GPN - A new index for assessing the Knock behaviour of gaseous fuels for large engines. Berlin, 2013

14 LDM LEC development method Gas related variables: Reactivity, sulphur content Methane number, calorific value, minimum air requirement for complete combustion Methane number, laminar flame speed Methane number, laminar flame speed, self-ignition temperature, minimum ignition energy, ignition limits Variation in methane number, variation in calorific value, density

15 LEC development success GE Jenbacher 624 Objective: Increasing efficiency and load in parallel to emission reduction of the gas scavenged pre-chamber combustion system GE Jenbacher 920 Electrical efficiency > 50%

16 CONTACT: Dipl.Ing. Wibke Tritthart Senior scientist Ao.Univ.-Prof. Dipl.-Ing. Dr. Andreas Wimmer CEO and Scientific Director LEC GmbH Inffeldgasse 19 A-8010 Graz, Austria Phone: +43 (316) Fax: +43 (316) Thank you for your attention! Funded by comet The K1 competence center LEC EvoLET is funded by "COMET - Competence Centres for Excellent Technologies Programme" of the Austrian Federal Ministry for Transport, Innovation and Technology (BMVIT), the Austrian Federal Ministry of Science, Research and Economy (BMWFW) and the Provinces of Styria, Tyrol and Vienna for the K1-Centre LEC EvoLET. The COMET Programme is managed by the Austrian Research Promotion Agency (FFG). All information contained in this document is the property of LEC GmbH.

17 Gas engine characteristics Emissions CO 2 emissions mg/m^3 NO x emissions Other: methane (slip), PM TA Luft 2002 EU Dir (TA Luft 2017) EU 2015 MCP Dir (2018) SI NG ENGINES 225 CI DIESEL ENGINES

18 Gas engine characteristics Efficiency Efficiency for power generation compared to CC Gas turbine Max. eff. turbine in CHP plant Lausward (Ger): 61% net electric efficiency (wrt LHV), overall ng efficiency factor: approx. 85% Max. eff. recip. engine: (GE J624): 46.3% electr., 89,3% total efficiency Both: full load Source: Kawasaki ( /en/energy/solutions/distrib uted_power/comparison.ht ml) [accessed Aug 2017]