Large Engines Competence Center

06-09-2017 Wibke Tritthart / Jan Zelenka / Gernot Kammel / Gerhard Pirker

CHALLENGES FOR LARGE GAS ENGINES IN FUTURE ENERGY SYSTEMS

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Large Engines

1

10

100

1000

10000

0 500 1000 1500 2000 2500

Dis

pla

cem

en

t [l

/cyl

.]

Engine Speed [rpm]

Low speed Medium speed High speed

Larg

e E

ngi

ne

s

2 l/cylinder

MAN 50/61DF

GE J920

MTU 2000

GE J616 Diesel

WÄRTSILÄRT flex 96c MSC OSCAR

Length app. 400 m> 19.000 Container

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Large engines – Fuels and applications

0

2000

4000

6000

8000

10000

12000

14000

Power generation Mechanical drives Marine

Diesel

HFO (heavy fuel oil)

Gas and dual fuel

28 000

Source: Basshuysen, Springer, 2015

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Gas engine potentialsIn renewable energy systems

Engine

Biomass

Biogas

Gasification

RenewableGases

H2

Fossil Resources

GasGrid

NaturalGas

Natural Gas H2

PowerToGas

CO2

MethanationCH4

Solar

Wind

Flare Gas

Industry

BFG

WasteGases

Electric Grid

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World natural gas market

Source: IEA Natural Gas Information Overview 2017

• 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). World natural gas demand (selected countries)

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Gas quality considerations

• 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

Gas market liberalisation: Europe

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Gas quality considerations

• Federal Energy Regulatory Commission (FERC) regulates

interstate transmission of Natural Gas

• Order 636: unbundling of transportation, storage and sales forpipeline&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

Gas market in US

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Bakken Shale

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.

Chicago

Boston

5% of global gas production wasted = 900 million tons/year of CO2

emissions!!!

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Variation of Natural Gas quality

• Wobbe Index → energy output of the fuel gas (Vc higher heating value, Gs

specific gravity)

EASEE / EN 16726:2013 and countries US

Gas engine relavant parameters

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Variation of Natural Gas quality

• 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 H2 = 0

• MN limit (in EN 16726:2015) = 65

Cylinder pressure for regular and knocking combustion

Gas engine relavant parameters

crank angle [°KW]

cylin

de

r pre

ssu

re p

[b

ar]

TDC TDC TDC

crank angle [°KW] crank angle [°KW]a) c)b)

> 50 bar

Shockwaves up to600 m/s

@http://my.prostreetonline.com/2016/06/21/common-engine-knock-causes/

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Gas quality studies

• Starting from a typical biogas / landfill gas composition

• Limits of mixing with Russian NG for WI and density

Component Symbol Units Biogas Landfill gas

Methane CH4 mol % 63 45

Oxygen O2 mol % - 1

Nitrogen N2 mol % - 14

Carbon dioxide CO2 mol % 37 40

Methane Number MZ - 137 149

Units EN 16726 EASEE

Landfill gas mol % 22 15

Biogas (aae digester) mol % 28 19

Hydrogen mol % 5 5

Calculation acc. to EN 16726:2013

WI

WI

density

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Gas quality studies

Admixture of 25%-20%-15%-

10%-5%-0%

Landfill gas (left) and

Biogas (right ) to Russian NG

red dot =pure CH4

Upper fig.: Wobbe Index limit

Lower fig.: MN

Wobbe Index and Methane number MN as function of H/C-ratio

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Further considerations

• Methane number calculation based on H/C-ratio, on EN 16726 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:

• H2S: Corrosion H2S + 3/2 O2 → H2O + SO2 → 𝐻2𝑆𝑂4

𝐻2𝑆𝑂3

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

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

LDM –LEC development method

Gas related variables:

Reactivity, sulphur content

Methane number, calorific value, minimum air requirement for completecombustion

Methane number, laminar flame speed

Methane number, laminar flame speed, self-ignition temperature, minimumignition energy, ignition limits

Variation in methane number, variationin calorific value, density

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

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%

Funded by comet

CONTACT:

Dipl.Ing. Wibke Tritthart Senior scientist Email: Wibke.tritthart@lec.tugraz.at

Ao.Univ.-Prof. Dipl.-Ing. Dr. Andreas Wimmer CEO and Scientific Director Email: andreas.wimmer@lec.tugraz.at

LEC GmbH Inffeldgasse 19 A-8010 Graz, Austria Phone: +43 (316) 873-30101 Fax: +43 (316) 873-30102 www.lec.at

Thank you for

your attention!

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.

LARGE ENGINES COMPETENCE CENTER © LEC GmbH

Emissions

• CO2 emissions

• NOx emissions

• Other: methane (slip), PM

Gas engine characteristics

500 500

200

500

100 95 225

0

500

1000

SI NG ENGINES CI DIESEL ENGINES

TA Luft 2002EU Dir. 2010(TA Luft 2017)EU 2015 MCP Dir (2018)

mg/m^3

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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 (http://global.kawasaki.com/en/energy/solutions/distributed_power/comparison.html) [accessed Aug 2017]

Gas engine characteristics