Post on 24-Dec-2015
transcript
Evaporative Emission Control for Gasoline Boat Fuel Systems
Mike Samulski
U.S. Environmental Protection Agency
International Boatbuilders’ Exhibition & Conference
October 20, 2005
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Evaporative Emissions from Boats
Refueling and spillage Diurnal, hot soak, and running loss
Permeation through fuel tank and hoses
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EPA’s Role
Clean Air Act (amended 1990)– section 213 applies to nonroad engines/equipment– “...greatest degree of emission reduction achievable
through the application of technology...”– consider cost, lead time, safety, energy
Past Efforts– implemented exhaust emission standards for the
majority of nonroad engines– evaporative emission standards for some applications
recreational vehicles, Large SI (>25 hp)
– originally proposed evaporative emission standards for marine in August 2002, but have not finalized
4
Rulemaking Plans
Scope– exhaust and evaporative emissions– gasoline-powered engines/vessels– build on 2002 NPRM
Schedule– anticipate proposal this spring– final rule ~ 1 year later
Marine Evaporative Emissions– tank permeation– hose permeation– diurnal breathing losses
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Rulemaking Process
gather information meet with stakeholders
Pre-Proposal
NPRM PublicComment
ImplementFRM
public hearing written comment period
publish “Notice of Proposed Rulemaking”
publish “Final Rulemaking”
lead time certification
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Tank Permeation Control
High Density Polyethylene (HDPE)– portable, PWC, and some installed fuel tanks– fluorination, sulfonation, Selar, multi-layer,
alternative materials Cross-Link PE
– installed fuel tanks (low volume production)– barrier coating, multi-layer roto-molding,
alternative materials, alternative constructions Fiberglass
– built-in installed fuel tanks– multi-layer construction
(Metal does not permeate)
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Hose Permeation Control
Multi-layer fuel hose– barriers used today in non-marine applications
(Teflon, THV, FKM, etc.)– marine barrier hose available as well– can add barriers to current marine constructions– > 95% reduction in permeation possible
Evaluating contribution of vapor versus fuel hose
rubber
barrier layer
cover
reinforcement
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Diurnal Breathing Loss Control
Portable fuel tanks– currently have manual seal without pressure relief– could use self sealing caps (1 way valve)
PWC– already have sealed systems with pressure relief valves– 1 psi ~ 50% reduction in-use from an open system
Larger fuel tanks– carbon canister in vent line
> 60% reduction with passive purge negligible back-pressure
– other technologies include bladder fuel tanks active purge canisters
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Other Evaporative Emissions
Venting emissions– running loss, hot soak, effusion– also reduced somewhat by
diurnal control systems
Refueling emissions– vapor displacement– spillage
both air and water pollution issue could be reduced through fuel system design configure fill neck for fuel shut-off before overflow valve to prevent liquid fuel from entering vent line
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Questions?
Mike Samulski
samulski.michael@epa.gov
www.epa.gov/otaq/marinesi.htm