Real-world vehicular emissions in the Indian megacity: Carbonaceous, metal and morphological characterization, and the emission factors

Abstract. A mobile laboratory equipped with state-of-the-art gaseous and particulate instrumentation was deployed across the Greater Toronto Area during two seasons. A high-resolution time-of-flight mass spectrometer (HR-TOF-CIMS) measured isocyanic acid (HNCO) and hydrogen cyanide (HCN), and a high-sensitivity laser-induced incandescence (HS-LII) instrument measured black carbon (BC). Results indicate that on-road vehicles are a clear source of HNCO and HCN, and that their impact is more pronounced in the winter, when influences from biomass burning and secondary photochemistry are weakest. Plume-based and time-based algorithms were developed to calculate fleet-average vehicle emission factors (EF); the algorithms were found to yield comparable results, depending on the pollutant identity. With respect to literature EFs for benzene, toluene, C2 benzene (sum of m,p,o-xylenes and ethylbenzene), nitrogen oxides, particle number concentration (PN), and black carbon, the calculated EFs were characteristic of a relatively clean vehicle fleet dominated by light-duty vehicles. Our fleet-average EF for BC (median: 25 mg kgfuel−1, interquartile range: 10–76 mg kgfuel−1) suggests that overall vehicular emissions of BC have decreased over time. However, the distribution of EFs indicates that a small proportion of high-emitters continue to contribute disproportionately to total BC emissions. We report the first fleet-average EF for HNCO (median: 2.3 mg kgfuel−1, interquartile range: 1.4–4.2 mg kgfuel−1) and HCN (median: 0.52 mg kgfuel−1, interquartile range: 0.32–0.88 mg kgfuel−1). The distribution of the estimated EFs provides insight into the real-world variability of HNCO and HCN emissions, and constrains the wide range of literature EFs obtained from prior dynamometer studies. Our results demonstrate that although biomass burning is a dominant source of both air toxics on a national scale, vehicular emissions play an increasingly important role at a local scale, especially in heavily-trafficked urban areas. The impact of vehicle emissions on urban HNCO levels can be expected to be further enhanced if secondary HNCO formation from vehicle exhaust is considered.

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Development of PN emission factors for the real world urban driving conditions of a hybrid city bus

Applied Energy ◽

10.1016/j.apenergy.2014.11.001 ◽

2015 ◽

Vol 138 ◽

pp. 488-495 ◽

Cited By ~ 6

Author(s):

Seref Soylu

Keyword(s):

Real World ◽

Emission Factors ◽

The Real ◽

City Bus ◽

Driving Conditions

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Plume-based analysis of vehicle fleet air pollutant emissions and the contribution from high emitters

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-8-2881-2015 ◽

2015 ◽

Vol 8 (3) ◽

pp. 2881-2912 ◽

Cited By ~ 3

Author(s):

J. M. Wang ◽

C.-H. Jeong ◽

N. Zimmerman ◽

R. M. Healy ◽

D. K. Wang ◽

...

Keyword(s):

Carbon Monoxide ◽

Black Carbon ◽

Time Resolution ◽

Real World ◽

Vehicle Emissions ◽

Particle Number ◽

Emission Factors ◽

Air Pollutant ◽

Automated Identification ◽

Vehicle Fleet

Abstract. An automated identification and integration method has been developed to investigate in-use vehicle emissions under real-world conditions. This technique was applied to high time resolution air pollutant measurements of in-use vehicle emissions performed under real-world conditions at a near-road monitoring station in Toronto, Canada during four seasons, through month-long campaigns in 2013–2014. Based on carbon dioxide measurements, over 100 000 vehicle-related plumes were automatically identified and fuel-based emission factors for nitrogen oxides; carbon monoxide; particle number, black carbon; benzene, toluene, ethylbenzene, and xylenes (BTEX); and methanol were determined for each plume. Thus the automated identification enabled the measurement of an unprecedented number of plumes and pollutants over an extended duration. Emission factors for volatile organic compounds were also measured roadside for the first time using a proton transfer reaction time-of-flight mass spectrometer; this instrument provided the time resolution required for the plume capture technique. Mean emission factors were characteristic of the light-duty gasoline dominated vehicle fleet present at the measurement site, with mean black carbon and particle number emission factors of 35 mg kg−1 and 7.7 × 1014 kg−1, respectively. The use of the plume-by-plume analysis enabled isolation of vehicle emissions, and the elucidation of co-emitted pollutants from similar vehicle types, variability of emissions across the fleet, and the relative contribution from heavy emitters. It was found that a small proportion of the fleet (< 25%) contributed significantly to total fleet emissions; 95, 93, 76, and 75% for black carbon, carbon monoxide, BTEX, and particle number, respectively. Emission factors of a single pollutant may help classify a vehicle as a high emitter. However, regulatory strategies to more efficiently target multi-pollutants mixtures may be better developed by considering the co-emitted pollutants as well.

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Development of an Empirical Model to Estimate Real-World Fine Particulate Matter Emission Factors: The Traffic Air Quality Model

Journal of the Air & Waste Management Association ◽

10.1080/10473289.2006.10464566 ◽

2006 ◽

Vol 56 (11) ◽

pp. 1540-1549 ◽

Cited By ~ 6

Author(s):

Ahmed S.M. Soliman ◽

Robert B. Jacko ◽

George M. Palmer

Keyword(s):

Particulate Matter ◽

Air Quality ◽

Empirical Model ◽

Real World ◽

Fine Particulate Matter ◽

Emission Factors ◽

Air Quality Model ◽

Quality Model ◽

Particulate Matter Emission ◽

Fine Particulate

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A framework for development of real-world motorcycle driving cycle in India

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407020977533 ◽

2020 ◽

pp. 095440702097753

Author(s):

Masilamani Sithananthan ◽

Ravindra Kumar

Keyword(s):

Fuel Economy ◽

Real World ◽

State Of The Art ◽

Emission Factors ◽

Driving Cycle ◽

Driving Cycles ◽

Traffic Scenario

This paper proposed a framework for development of real-world driving cycle in India after a thorough review and comparison of motorcycle driving cycles used in different countries. A limited state-of-the art work for the development of driving cycles for motorcycles is available. The motorcycle driving cycles developed by different countries differ from each other in terms of their driving cycle characteristics, emission factors, and fuel economy. This paper reviewed the parameters of real-world driving cycles of motorcycles and compares the same with legislative cycles concerning their characteristics and emissions. The parameters of real-world driving cycles and Indian legislative cycle (IDC) deviate significantly from other legislative cycles in the range of −97% to +1172% and −74% to 284% respectively. The emission factors of the legislative cycle do not match with the realistic emissions measured by real-world driving cycles. This is due to the reason that the legislative cycles do not represent the current traffic scenario and hence need to be revised. A framework is proposed to develop a real-world driving cycle in India.

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