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INTERNAL USE ONLY

Wartsila Proposals for Exhaust Gas Emissions Abatement

P. Tremuli 22.1.2008

2 © Wärtsilä

Agenda

1) Introduction

2) Key legislation

- Marine exhaust emissions legislation

- Wartsila engines vs. Legislation

3) Abatement technologies

- Wet Low NOx technologies

- Gas Engines

- SCR technology

- Scrubbing technology

- Common Rail

3 © Wärtsilä

Map to Lower Emissions

Exhaust GasEmission

Abatement

PRIMARY

METHODS

SECONDARY

METHODS

COMBUSTION

CYCLE

ENHANCEMENT

ENGINE

MODIFICATION

NOX

SOX

PARTICULATEMATTER

PM

LOW NOX

COMBUSTION

DOUBLE STAGETURBOCHARGING

WITH HIGH MILLER

COMMON RAIL

SMOKE

FUEL

CONSUMPTION

CO2

GAS ENGINES

WET METHODS

SELECTIVE

CATALYTIC

REDUCTION

SCR

SCRUBBER

PARTICULATE

FILTERS

DPF

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INTERNAL USE ONLY

KEY LEGISLATION

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Marine exhaust emissions legislation

• IMO (International Maritime Organisation)

• EU (European Union)

• SECA (Sulphur Emission Control Areas)

• EPA (Environmental Protection Agency - U.S.)

• Local Authorities

• Alaska

• California

• Canada

• River Rhine

• Norway, Sweden… (European Fee Incentive Programs)

• Voluntary Emission Reduction Programs

• American Bureau of Shipping ABS

• Bureau Veritas BV

• Det Norske Veritas DNV

• Lloyd's Register LR

• Registro Italiano Navale RINA

• Russian Maritime Register Of Shipping

6 © Wärtsilä

Transition of NOx emission limitsN

Ox g

/kW

h

20

07

20

11

20

15

20

20

2

8

16

IMO (slow speed engine)

IMO (high speed engine)

EPA NOx+HC

EU NOx+HC2

00

5

17

9.8

15

13.5~

10.2

7.8

6.3~

4.9

3.4

1.96

10.2

20

00

7.8

EPA Tier I

EPA Tier II

EPA Tier III

EPA Tier IV

-2 / -3.5 g/kWh

IMO Tier II

IMO Tier III

Norway proposal

IMO Tier III

Japan proposal

11

7 © Wärtsilä

Transition of SOx emission limits

Year

S in

fue

l (%

)

1

4

3

2

07 171615141312111009080605

IMO actual limitin Baltic SeaSECA area

IMO actual limitin

North Sea & EnglishChannel

SECA area

IMO actual Global cap

Option BGlobal cap

Option Bfor SECA areas

Option B1 (US)in costal areas X miles

from shore

Option B2 (BIMCO)Global Cap

Option B2 (BIMCO)for SECA areas

Option COnly distillates

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Next SECAs

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Wartsila Engines’ Portfolio vs. Legislation

SP

EC

IFIC

NO

E

MIS

SIO

NS

(g

/kW

h)

x

4

6

8

10

12

14

16

0 200 400 600 800 1000 1200 1400 1600 1800 2000

2

RPM

18

20

0

IMO limit

Low NOx comb.Wetpac E

SCR

W64 W46 W38 W32 W26 W20RTA

x

n < 130 rpm 17,0 g/kWh

130 rpm ≤ n < 2000 rpm 45 x n -0,2 g/kWh

n ≥ 2000 rpm 9,8 g/kWh

Wetpac

10 © Wärtsilä

Wartsila Gas Engines’ Portfolio vs. Legislation

SP

EC

IFIC

NO

E

MIS

SIO

NS

(g

/kW

h)

x

4

6

8

10

12

14

16

0 200 400 600 800 1000 1200 1400 1600 1800 2000

2

RPM

18

20

0

IMO limit

Low NOx comb.Wetpac E

SCR

W50DF W34DF

n < 130 rpm - > 17,0 g/kWh

130 rpm ≤ n < 2000 rpm -> 45 x n -0,2 g/kWh

n ≥ 2000 rpm - > 9,8 g/kWh

Wetpac H

Gas mode operation

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INTERNAL USE ONLY

ABATEMENT TECHNOLOGIES

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NOx vs. CO2C

O2

& P

art

icu

late

NOx

NO MIRACLES!!!NO MIRACLES!!!

Reduction Reduction targettarget

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Low NOx Combustion

– High combustion air temperature at injection

start

– Short injection period

– Good fuel atomization

– Optimal combustion space geometry

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Wet Low NOx Technologies

NOx reduction due to:

• Lower combustion air temperature through vaporization of the liquid water prior to and/or during combustion

• Increased heat capacity of the cylinder charge, which reduces the temperature increase during combustion

• Dilution of oxygen concentration in the cylinder charge

Wetpac H Wetpac EWetpac DWI

Three Wetpac technologies have been developed/tested:

Direct Water Injection Humidification Water-fuel-Emulsions

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Wetpac DWI (Direct Water Injection)

Strengths

• High NOx reduction level achievable: 50%• Water-to-Fuel ratio typically: 0.7• Low water consumption compared to Humidification • Water quality is less crucial compared to Humidification• Air duct system can be left unaffected – no risk for corrosion/ fouling of CAC, etc• Flexible system – control of water flow rate, timing, duration and switch off/on• Less increase of turbocharger speed and less drift towards compressor surge line compared to the Humidification method due to no increase of rec. temp. and less water flow – high engine load can be achieved and high (50%) NOx reduction also at full engine load• No major change in heat recovery possibilities• Good long term experiences with low sulphur fuels (<1.5%)

Weaknesses

• High fuel consumption penalty• Increased smoke formation especially at low loads

• Remedy: switch off or less water at low load• More complicated/expensive system compared to Humidification• Challenges in terms of piston top and injector corrosion with high sulphur fuels (>1.5%)

TechnologyH:\GHn\Env_ bookle t\section_ 7\s_7 A_13 .PPT

NOx Reduction - Primary Measures

Water

Water Pressure200 - 400 bar

Water Needleand

Fuel Needlein the Same

InjectorFuel Pressure

1200 - 1800 bar

Fuel

DWI system with “Tandem-nozzle”

TechnologyH:\GHn\Env_ bookle t\section_ 7\s_7 A_14 .PPT

NOx Reduction - Primary Measures - Principle of theDWI System with “Tandem Nozzle”

Flow fuse

High pressureWater Pump

Watertank

Water

Fuel

Water needle

Fuel needle

Solenoidvalve

Control unit

T

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Wetpac H (Humidification)

Strengths

• Only marginal increase of SFOC• Less complicated/expensive system compared to DWI• Flexible system – control of water flow rate and switch off/on

Weaknesses

• Lower NOx reduction (40%) compared to DWI (50%)• High water consumption compared to DWI

• Very clean water is required in order to avoid fouling/corrosion of CAC and air duct system

• Major change in heat recovery possibilities - less cooling water heat available for production of clean water• Water-to-fuel ratio 1,3÷2

• Turbocharger speed increase and drift towards compressor surge line due to increased rec. temp. and high water flow

• By-pass is required (anti-surge device)• Not possible together with pulse charging systems

• Full NOx reduction (40%) can not normally be achieved at full engine load and low loads

• Increased smoke formation especially at low loads• Remedy: switch off or less water at low loads

• Limited long term experience• Unacceptable corrosion observed in the air duct system including CAC on 500h endurance test with high sulphur fuel (3%)• Encouraging lab and field experiences (rather few hours) with low sulphur fuel and low NOx reduction levels (about 30%)

Evaporised water is partly re-condensingin the charge air cooler

Compressor

Heat from cooling wateris reducing re-condensing

Water injection 130-135 bar

Saturated air40…70°C

Injected water mist is evaporated and hot air after compressor is cooled tosaturation point

Unevaporised watercaptured in WMC and re-circulated

Standard Wetpac H unit

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Wetpac E (water-fuel Emulsions)

Strengths

• Only marginal increase of SFOC • Reduced smoke formation especially at low load• Low water consumption compared to Humidification

• Water-to-fuel ratio 0,3• Almost similar to that of DWI, but due to low NOx reduction the water consumption is low

• Water quality is less crucial compared to Humidification• Less increase of turbocharger speed and less drift towards compressor surge line compared to the Humidification method, due to no increase of rec. temp. and less water flow – high engine load can be achieved• No major change in heat recovery possibilities

Weaknesses

• Low NOx reduction potential (15-20%)• Limited flexibility

• Increased smoke formation and poor engine performance due to too large nozzles in case of switching off the system

• Increased mechanical stress on the fuel injection system in case ”standard” nozzles are used

• Limited long term experience• 400h endurance test showed extreme turbine nozzle ring fouling

• Root cause was very bad water quality

Water droplets inside fuel droplet

Fuel Oil droplet

18 © Wärtsilä

0

0.5

1

1.5

2

2.5

3

0 10 20 30 40 50 60

Wetpac – NOx reduction potentials and typical fuel consumption penalties

DWI

Emulsion

In

crea

se o

f S

pec

ific

Fu

el C

on

sum

pti

on

(%

)

NOx reduction (%)

Humidification

Achievable withWetpac H (Marine)

Achievable withWetpac DWI

Achievable withWetpac E

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NOx Reduction with Selective Catalytic Reduction (SCR Catalyst)

Control Control UnitUnit

BoilerBoiler

Urea Urea TankTank

Dosing Dosing UnitUnit

Compressed Compressed AirAir

SilencerSilencer

Selective Selective Catalytic Catalytic ReactorReactor

Pumping Pumping UnitUnit

Performance NOx reduction 85-95%

HC reduction 75-80%

Soot reduction 20%

Sound Attenuation 20 dB (A)

Operation Temperature Span 300-500 °C

Fuel MGO/MDO/HFO

Specific costs Invest cost 25-50 €/kW

Running cost 2-4 €/MWh

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Marine SCR reference list 2006 Totally more than 100 engines with SCR installed

Vessel Engines Delivery Fuel Notes

Aurora af Helsingborg 1 x WV6R32 1992 MDO

Silja Serenade 1 x WV8R32 1995 HFO 0.5% S

Silja Symphony 1 x WV8R32 1995 HFO 0.5% S

Gabriella 1 x WV6R32 1997 HFO 0.5% S Retrofit

Thjelvar 2 x WV4R32 + 4 x WV12V32 1997 HFO 0.5% S Compact SCR

Birka Princess 4 x WV12V32 + 2 x WV6R32 + 1 x WV4R32

1999 1999

HFO 0.5%S HFO 0.5%S

Compact SCR, retrofit Compact SCR, retrofit

M/V Spaarneborg 1 x 7RTA52U + 2 x W6L20 1999 HFO + MDO

M/V Schieborg 1 x 7RTA52U + 2 x W6L20 1999 HFO + MDO

M/V Slingeborg 1 x 7RTA52U + 2 x W6L20 2000 HFO + MDO

Visby 4 x 12V46 + 3 x 9L20 2000 HFO Compact SCR

Gotland 4 x 12V46 + 3 x 9L20 2000 HFO Compact SCR

Birka Exporter 1 x WV16V32 2000 HFO Compact SCR, retrofit

Birka Transporter 1 x WV16V32 2002 HFO Compact SCR, retrofit

Birka Shipper 1 x WV16V32 2001 HFO Compact SCR, retrofit

Birka Paradise 4 x 6L46 + 4 x 6L32 2002 HFO Compact SCR

Tallink Victoria 4 x 16V32LNE + 3 x 6R32LNE 2002 HFO Compact SCR

Balticborg 1 x 9L46C 2003 HFO <1%S

Bothniaborg 1 x 9L46C 2004 HFO <1%S

Normand Skipper 4 x 6R32LNE 2005 MDO

Tallink Galaxy 4 x 16V32LNE + 3 x 6R32LNE 2006 HFO

Ulstein 275 4 x 9L20 2006 MDO Ulstein 276 4 x 9L20 2007 MDO Flekkefjord 186 2 x 8L32 + 1 x 6L20 2007 MDO

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Dual Fuel

Used on W34DF and W50DF

* ** ** * **

******

** **

***

**

Intake ofair and gas

Compression ofair and gas

Ignition bypilot diesel fuel

Otto principle

Low-pressure gas admission

Pilot diesel injection

Gas mode: Ex. In. Ex. In.Ex. In.

Intake ofair

Compression ofair

Injection ofdiesel fuel

Diesel principle

Diesel injection

Diesel mode:Ex. In. Ex. In.Ex. In.

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Dual Fuel

Operatingwindow

The

rmal

effi

cien

cy [

% ]

NO

x em

issi

ons

[ g /

kW h

]

BM

EP

[ ba

r ]

Air / Fuel ratio

Knocking

Mis

firin

g

Optimum performancefor all cylinders

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Emissions

0%

20%

40%

60%

80%

100%

120%

HFO DF

CO2 NOX SOX

CO2 -30%

NOX -85%

SOX -99.9%

– Very low particulate emissions– No visible smoke– No sludge deposits

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LNG tanks

LNG tank location• Rule requirements

– From side: B/5– From bottom: B/15 or 2 m

(the lesser)

• Novel location in cruise ships– In centre line casing– Free ventilation to open air– Fire insulated space– “Drip tray” below tanks

capable of containing the fuel of an entire tank

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LNG in Europe

Import terminal

Export terminal

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SOx - Solutions for compliance

Clean exhaust gas

Fuel Solutions

Amongst the solutions on the fuel strategy side, we can list the following:

– Running MDO– Balance emissions by running

different fuel on different engines– Running on 1,5%S fuel– Blend fuel before use

Not much can be done at engine level to reduce sulphur emission:what is in the fuel will be found in the exhaust gases.

Cleaning exhaust gases with scrubber has a long track record on land base applications. The technology is about to be applied for Marine installation.

– Seawater scrubber– Freshwater scrubber

+ alkaline additive– Combination of the above

• Emission trading could have been a solution but it is not yet in place for SOx.• Cold ironing by definition is only proposed at berth, an consequently can not be

considered as a solution for SOx abatement at sea.

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General outlook of Marine Scrubber System

Scrubber

pHpH

NaOH unitFresh or Greywater source

WaterTreatmentHeat

Exchanger

Seawater pH management with seawater

pH

• This process is an closed loop system.

• Closed loop needs freshwater, to which NaOH is added for the neutralization of SOx.

Exhaust Gas

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Equipment Compounds 1 (all-in-one)

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Equipment Compounds 2 (all-in-one)

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Fuel Injection – Common Rail

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Fuel Injection – Common Rail

Used on W32, W38 and W46

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Extreme Miller cycle

• NOx reduction up to 50%

• 10% Fuel consumption reduction

• Thermal loading enhancement

•Good load acceptance with Variable Inlet closing

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Extreme Miller

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2 Stage Turbocharging

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Thank you!