Transcript Locomotive Exhaust Emissions

Alternative Fuels for Medium –Speed
Diesel Engines for Marine
Applications:
Realistic Options
by
Steven G. Fritz, P.E.
Department of Engine and Emissions Research
Southwest Research Institute®
210-522-3645
[email protected]
Topics Covered Today
* Medium Speed Diesel Engines
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Primary experience base from North American railroad industry
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EPA locomotive regulations in place starting 2000
New 2000 and newer
Remanufactured – 1973 and newer
Engine commonality with Category 2 marine
* Context & Perspective
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Railroad/marine diesel fuel consumption
EPA marine engine & fuel regulations
* Alternative Fuels:
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Biodiesel
Renewable Diesel
Synthetic Diesel
* Greenhouse gas emissions
“......Realistic Options”
* For today, means that:
» Near term -- 0 to 5 years out
» Potential beyond demonstration
* We will not focus on
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Hydrogen
DME (Dimethyl Ether)
Propane (LPG)
Coal slurry fuels
Context
* Railroad’s use a small fraction of
diesel fuel production
» In general, they will use what everyone
else is using
» It is what is in the pipeline
* Same story for marine?
EPA Diesel Fuel Regulations
* Nonroad diesel not regulated by EPA until June 2007.
* EPA Nonroad diesel regulations
» Including locomotive and marine diesel – nationwide
» Effective June 1, 2007
– 500 ppm Sulfur maximum
– Cetane > 40
– Aromatics < 35% volume
* June 2012
» Locomotive and marine diesel will be ULSD, 15 ppm max Sulfur
* The above sulfur limits do not apply to HFO used in
Category 2 and 3 marine diesel engines.
CARB Diesel Fuel Regulations
* Effective January 1, 2007
» Intrastate Locomotive & Harbor Craft marine
* Must use CARB diesel
» 15 ppm maximum Sulfur
» 10% maximum aromatics
» Minimum lubricity standard
Source: EPA Regulatory Support Document EPA420-R-08-001 March 2008
Apply Technologies to Marine EMD Engines
What about Alternative Fuels?
* OK, we’re getting there
* But remember,
» Marine engines now operating in a highly EPA
regulated environment
» Covering both engines and fuels
» Most available resources directed at meeting
upcoming Marine Tier 3 & Tier 4 regulations
» You just can’t switch to an “alternative fuel”
without factoring in EPA emissions compliance
on regulated engines
Biodiesel
* Limited experience with
Biodiesel in locomotives
* 2002 SwRI study for DOENREL
» EMD 16-645E at 2,000 HP
http://www.biodiesel.org/resources/reportsdatabase/reports/gen/20040401_gen334.pdf
Biodiesel Issues
* Issues for locomotive/marine engine remain
» New engine warranty
» EPA emissions compliance
– Close to the limits on NOx for best fuel economy
– Will NOx increase with biodiesel use above EPA limits?
» Lower energy density (BTU/gallon)
– Roughly 2% for a B20 blend
» Consistent fuel quality remains a major concern
– 10% of B100 was out of specification in 2007
» Required NOx inventory reporting
– Need to adjust NOx up if biodiesel is used?
Renewable Diesel
* Usually refers to hydrotreated vegetable oils
(HVO) or animal fats.
* Identical to those used for ester-based biodiesel
production
* Treated with hydrogen in a refinery process
» Removes oxygen
» Resulting in a paraffin fuel similar to Fischer-Tropsch/GTL
diesel.
* An attractive method of vegetable oil feedstock
utilization, producing hydrocarbon fuel with no
stability, low temperature operability, or engine
compatibility problems which have troubled
biodiesel.
Renewable Diesel – In Production Today
* Finnish oil company Neste.
» Originally introduced NExBTL diesel as “2nd generation
biodiesel”
» Now NExBTL “renewable diesel”
» Neste Oil’s first NExBTL facility was commissioned in Finland at
the Porvoo refinery in Summer of 2007
» A second facility is due to come on stream there in 2009. Each
of the plants at Porvoo has a capacity of 170,000 tons per
annum (t/a).
» In November 2007, Neste announced a 800,000 t/a plant in
Singapore
» In June 2008, Neste announced 800,000 t/a plant in
Rotterdam
* No commercial renewable diesel plants in North America.
* Under April 2008 decisions of the US Internal Revenue
Service (IRS) and the US Environmental Protection Agency
(EPA), refinery-made renewable diesel is eligible for the
EPAct $1/gallon tax credit.
Synthetic Diesel Fuel
* First and best known synthetic fuel
technology is the Fischer-Tropsch (FT)
process, which was developed in the
1920s in Germany
Synthetic Diesel Fuel, cont.
* GTL – Gas to Liquid
» In commercial, large scale production today
» Oryx GTL—was opened by Sasol Chevron in
2006/2007 in Qatar.
» Syntroleum Corporation in Tulsa, OK – USAF
project
* CTL – Coal to Liquid
» Sasol in South Africa - synthetic diesel projects
via coal gasification and synthesis gas.
Synthetic Diesel Fuel characteristics
* Generally compatible with existing engines
» no need for engine modifications
» Use neat or as a blend with conventional diesel fuel
* Compatible with conventional diesel
» comparable energy density (BTU/gallon)
» can be mixed with petroleum diesel
» can be transported as liquid in existing petroleum infrastructure
* The fuels can be designed to have very good properties for both
engine performance and emissions.
* Can be used neat or as a valuable blending stock
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to improve the properties of petroleum fuels
Very high Cetane (70+)
Very low aromatic and polyaromatic content
Sulfur content is essentially zero
Synthetic Diesel Fuel characteristics
* However.....
» Poor lubricity – needs a lubricity additive
» Poor cold flow properties
* Production cost ???
* GHG Considerations
» GTL – ?
» CTL – negative
» Biomass derived – may have life cycle GHG benefit
Summary
* Railroad/Marine diesel consumption a relatively
small fraction of total diesel consumption
* “Alternative Fuel” options are available today
» Likely already in use as B5 in D975-08 diesel fuel.
» Synthetic Diesel (GTL & CTL) viable options -- $$$
* Do not forget EPA exhaust emission & fuel
regulations
» You can not just go and try anything in the tank.....