Evaluation of Locomotive Emissions Reduction Strategies
Older diesel locomotives may have higher per passenger mile emission rates of nitrous oxide (NOx) and particulate matter (PM) compared to other transport modes. Therefore, to reduce human exposure to train-generated air pollution, measures to reduce emissions from existing locomotives are desirable. Fuel use and emission rates (FUER) depend on exhaust after-treatment technology, locomotive operation, and fuels. Variation in locomotive operation results in spatial variation of FUER along the route. Thus, there could be hotspot locations with high emissions. Switching fuels to biodiesel blends affects FUER due to differences in fuel physical and chemical properties. Here, interactions between technology, operation, and fuels were evaluated. Rail yard (RY) and over-the-rail (OTR) measurements were conducted using portable emission measurement system (PEMS) to quantify FUER. Data from multiple measurements were time-aligned and screened for errors. RY measurements included three replicates of a predefined test schedule. OTR measurements included 6 one-way trips on the Piedmont rail route between Raleigh, NC and Charlotte, NC. The retrofit of a selective catalytic reduction-based Blended exhaust After Treatment System (BATS) for controlling NOx emissions was evaluated based on RY measurements. Simultaneously, PEMS-based emission rates were benchmarked to a Federal equivalent method (FEM). The effect of operation was assessed by comparing one-way trips with the highest and lowest trip total fuel use and emissions. Spatial variability in FUER was compared to spatial variability in train speed, acceleration, rail-grade and rail curves. In prior work, FUER were quantified for several blends of biodiesel and diesel. Less than 1% of the data were excluded during screening. PEMS-based emission rates of carbon dioxide (CO₂), NOx and PM were highly correlated with the FEM. BATS is highly recommended for reducing NOx emissions. Efficient locomotive operation including fewer notch changes and avoiding rapid accelerations and decelerations is recommended for reducing trip total fuel use and emissions. A 20 percent blend of biodiesel in diesel is effective in reducing CO, HC and PM emission rates. A combination of technology, operation and fuels is highly recommended to simultaneously reduce fuel use and emissions of CO, HC, NOx and PM. This research demonstrates that PEMS-based measurements are reliable for quantifying the effect of technology, operation and fuels on FUER.
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- Summary URL:
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Corporate Authors:
North Carolina State University
Department of Civil, Construction and Environmental Engineering
Raleigh, NC United States 27695North Carolina Department of Transportation
Raleigh, NC United StatesFederal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC United States 20590 -
Authors:
- Frey, H Christopher
- Rastogi, Nikhil
- Publication Date: 2018-10
Language
- English
Media Info
- Media Type: Digital/other
- Edition: Final Report
- Features: Appendices; Figures; Photos; References; Tables;
- Pagination: 228p
Subject/Index Terms
- TRT Terms: Air quality management; Biodiesel fuels; Diesel locomotives; Emission control devices; Evaluation and assessment; Fuel consumption; Locomotive operations; Nitrogen oxides; Particulates; Pollutants; Spatial analysis; Speed
- Identifier Terms: Portable Emissions Measurement System
- Geographic Terms: North Carolina
- Subject Areas: Energy; Environment; Railroads;
Filing Info
- Accession Number: 01712417
- Record Type: Publication
- Report/Paper Numbers: FHWA/NC/2016-20
- Contract Numbers: NCDOT Project 2016-20
- Files: TRIS, ATRI, USDOT, STATEDOT
- Created Date: Jul 24 2019 10:35PM