Transcript Rich Kolb

Background
• 1990 Clean Air Act Amendments required the
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EPA to issue regulations for cleaner burning
gasoline
After 5 years of regulation - negotiation (RFG)
Phase I is required beginning 1/1/95, in 9
metropolitan areas designated ozone
“nonattainment zones” (New York,
Philadelphia, Hartford, Baltimore, Chicago,
Milwaukee, Houston, San Diego, Los Angeles)
RFG Phase II required January 1, 2000
RFG Gasolines
• Based on the EPA’s simple model are
intended to reduce :
– volatile organic compounds (VOC)
– air toxic emissions
RFG Gasoline
• Limits Reid Vapor Pressure (RVP)
– Measure of how quickly fuel evaporates
• Limits the amount of benzene
• Requires use of oxygenates (amended
2006 to optional)
RVP Comparison
Conventional
Phase I
Phase II
Gasoline
RFG
RFG
Average
8.7 Summer
7.2 Summer 6.8 Summer
RVP (PSI)
12.2 Winter
12.2 Winter
12.1 Winter
Oxygenates
• Chemical compounds that contain oxygen
which are required by EPA regulations in
RFG (Amended in 2006 to be optional)
Oxygenate Substances
• Ethers
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Methyl tertiary butyl ether (MTBE) *
Ethyl tertiary butyl ether (ETBE)
Tertiary amyl methyl ether (TAME)
Di-isopropryl ether (DIPE)
• Alcohols
– Ethanol (EtOH) *
– Tertiary butyl alcohol (TBA)
*Most common in use today
Oxygenates Comparison
Conventional
Gasoline
Ave.Vol.%
MTBE
__ *
EtOH
__*
Phase I
RFG
-
11 **
(7.8-15)
5.7 **
(4.3-10)
Phase II
RFG
11 **
(7.8-15)
5.7 **
(4.3-10)
* Some fuels have used oxygenates (in lesser volumes) as octane
enhancers especially since the phase out of tetra ethyl lead.
** Combinations of MTBE and EtOH are permissible but cannot
exceed 15% volume total
MTBE
• Advantages
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Easily manufactured and blended
Compatible with fuel components
Low blending RVP
Does not need special handling to avoid water
contamination
• Disadvantages
– most aggressive (Chemically) to elastomers of all
the ethers in a neat (pure) state
– Not eligible for tax credits
– Has an offensive smell when blended into fuel
– Ground water hazard
EtOH (Ethanol)
• Advantages
– Eligible for tax credits
– Less expensive that MTBE
• Disadvantages
– Cannot be shipped in typical gasoline pipelines
– Must be handled in a special manner to avoid
water contamination
– Scavenges water in storage and distribution
systems which remains in the fuel blend
E10 Fuel retrieved from a
boat in 2006
E10 Effects on Marine Engines
and Fuel Systems
• Fuel system parts particularly some
plastics and elastomers (rubbers) such
as seals, o-rings, and hoses may shrink,
swell, lose flexibility, lose mechanical
strength, and exhibit increased
permeation rates when exposed to E10
Effects of E10 on Traditional
Rubber Components
Automotive Plastic Gas Tank
Permeation Comparison
Conventional Gasoline Vs. E10
Tank Barrier Conventional
Treatment Gasoline
RFG
_____________________________________________________________________________________________
______________
NonTreated
Sulfonated
Coextruded
10g/day
0.2g/day
0.05g/day
10g/day
0.5g/day
0.1g/day
E10 Effects on Marine Engines
and Fuel Systems
• Increased tendency to experience water in
fuel problems
• E10 appears to be more affected by
having a vacuum drawn on it
• Boats may need larger fuel tanks to travel
the same distance as before due to lower
energy content of the fuel
E10 Effects on Marine Engines
and Fuel Systems
• Fuel storage must be handled more
carefully as vapor in the storage vessel (or
boat tank) may contain its own oxygen
making the mixture flammable at colder
temperatures
• Poorer starting in colder weather may be
experienced in the spring season due to
lower RVP
E10 and Engine Manufacturers
• Using more sophisticated elastomers in
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the fuel system
Using more stainless steel in fuel system
components
Building in water traps in critical
components of the fuel system
Adding “water - in fuel” sensors
Increasing filtration
Increasing vapor handling capacities
RFG (E10) and Engine Manufacturers
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Eliminating hoses in the fuel system
Using fewer reusable clamps and joints
Using preassembled fuel line assemblies
Using higher capacity fuel pumps
Cooling fuel to hold down vapor
Future Expectations for
Boat Manufacturers
• More demands from customers and engine
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manufacturers to provide more reliable fuel
systems
Increasing use of EtOH in fuels (eventually
nationwide) as Congress advances new
legislation
Similar low pollution diesel fuel blends which
will also create its own set of new challenges
(biodiesel has similar effects on elastomeric
components)
New Boat Fuel Systems
• Evaluate those components used in new
boat fuel systems. Hoses, anti-siphon
values, gauge senders and even gas
tanks may be affected adversely by E10.
Ask before you buy.
• Add a water separating fuel filter to your
boat fuel system if you don’t already have
one.
New Boat Fuel Systems
• Pay attention to hose diameters, fittings,
and lengths to keep restrictions as low as
possible. Fuel system restrictions are
more critical than ever
• Eliminate potential leak paths wherever
possible
Existing Boat Fuel Systems
• Inspect hoses often looking for cracks,
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sponginess, leakage (wet on surface), stiffness,
and loss of clamping force - these are
indications of hose deterioration
Add a water separating fuel filter if the boat is
not so equipped
inspect all gasketed areas looking for wicking of
fuel
Inspect fuel tanks for signs of deterioration
– Fiberglass – softening , sponginess, leakage
– Aluminum – corrosion, leakage
Existing Boat Fuel Systems
• Use your nose!
– If you smell vapor find the cause immediately
• If you are replacing components, make sure they
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are compatible with E10
Avoid the use of “SNAKE OIL” Fuel additives
– Use only those stabilizers and fuel system cleaners
that are approved by the engine manufacturers
Future Expectations
• Further regulatory requirements centered
around spillage and evaporative emissions
Additional References
http://www.nmma.org/government/environmental/?catid=573
http://www.epa.gov/oms/rfgboats.htm