1 / 19

Giorgos Mellios and Leon Ntziachristos

Giorgos Mellios and Leon Ntziachristos. Updated methodology for estimating evaporative VOC emissions. Copenhagen, 17 th June 2008. Recent updates. Chapter 0706 (Gasoline Evaporation from Vehicles) of the Guidebook was updated in August 2007

kadeem-weaver
Download Presentation

Giorgos Mellios and Leon Ntziachristos

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Giorgos MelliosandLeon Ntziachristos Updated methodology for estimating evaporative VOC emissions Copenhagen, 17th June 2008

  2. Recent updates • Chapter 0706 (Gasoline Evaporation from Vehicles) of the Guidebook was updated in August 2007 • The chapter has been extensively reviewed by a number of expert users; mistakes were identified and corrected and the updated chapter will be included in the revised Guidebook • The new methodology and emission factors were incorporated in COPERT 4 Version 5.0 in December 2007

  3. Evaporative emissions from gasoline vehicles • Emission sources • Breathing losses (fuel tank, activated carbon canister) • Fuel permeation and/or leakage (fuel and vapour control systems) • Mechanisms causing evaporative emissions • Diurnal emissions • Hot soak emissions • Running losses Parked vehicle Vehicle engine running

  4. Background data • Joint JRC/CONCAWE/EUCAR Programme on Evaporative Emissions • 7 vehicles • 10 fuels (including ethanol blends) • Regulatory SHED test procedure • LAT/CONCAWE/JRC work • 5 vehicles • 3 fuels (HC only) • Modified test protocol (improved vehicle preconditioning, more temperature profiles, consecutive diurnal tests, permeation tests) • Literature data • Motorcycles (Artemis) • Carburetted and uncontrolled vehicles (older CONCAWE studies)

  5. Activated carbon canister loading with fuel vapour • Canister weight: • a, b are linear functions of temperature & vapour pressure vapour load breakthrough emissions Vapour pressure effect Temperature effect

  6. Fleet emissions calculation • Total evaporative emissions: Eeva,voc,j= 365 ∙ Nj ∙ (HSj + ed,j + RLj) • Hot soak emissions HSj = x {c [p ∙ es,hot,c + (1 – p) ∙ es,warm,c] + (1 – c) ∙ es,hot,fi} • Running losses RLj = x {c [p ∙ er,hot,c + (1 – p) ∙ er,warm,c] + (1 – c) ∙ er,hot,fi}

  7. Overview of the calculation procedure Input parameters Fuel vapour pressure (kPa) Tank size (l) Canister size (small, medium, large) Fuel tank fill level (%) Temperature variation (°C) Cumulative mileage (km) Intermediate calculations Fuel vapour generation (g) Initial canister weight (g) Canister breakthrough emissions (g) Permeation and/or leakage emissions (g) Total evaporative emissions (g)

  8. Parking time distribution • Parking duration distributed into 24 time classes ranging from <0.5 to >11.5 h • Each combination of parking duration and parking end-time has a probability factor fk • ∑fk = 1

  9. Parking time distribution

  10. Intermediate calculations • Fuel tank vapour generation (g) • Canister breakthrough emissions (g) • Permeation and leakage emissions (g)

  11. Emission factors – Gasoline passenger cars • Diurnal emissions (g/day) • Canister-equipped • Uncontrolled

  12. Emission factors – Gasoline passenger cars • Hot soak emissions (g/procedure) • fuel injection and returnless fuel systems • carburettor and/or fuel return systems • uncontrolled

  13. Emission factors – Gasoline passenger cars • Running losses (g/trip) • fuel injection and returnless fuel systems • canister-equipped with carburettor and/or fuel return systems • uncontrolled with fuel return systems

  14. Emission factors – Motorcycles • Diurnal emissions (g/day) • Canister-equipped • Uncontrolled

  15. Emission factors – Motorcycles • Hot soak emissions (g/procedure) • canister-equipped • uncontrolled

  16. Emission factors – Motorcycles • Running losses (g/trip) • canister-equipped with carburettor and/or fuel return systems • uncontrolled with fuel return systems

  17. Comparison with COPERT III – controlled vehicles • Compared to the new methodology, COPERT III: • overestimates diurnal and running losses • underestimates the effect of temperature and/or overestimates the effect of fuel volatility

  18. Comparison with COPERT III – uncontrolled vehicles • Compared to the new methodology, COPERT III: • overestimates diurnal and running losses • underestimates the effect of temperature and/or overestimates the effect of fuel volatility

  19. Contributions to total emissions • Fleet information and exhaust emissions taken from TREMOVE v2.5 • Observed differences on a country level are due to differences in ambient temperatures (minimum and maximum), fuel volatility, vehicle usage (annual mileage) and technology mix (share of older uncontrolled vehicles, diesel vehicles, etc)

More Related