scholarly journals Technical note: Emission factors, chemical composition and morphology of particles emitted from Euro 5 diesel and gasoline light duty vehicles during transient cycles

2020 ◽  
Author(s):  
Evangelia Kostenidou ◽  
Alvaro Martinez-Valiente ◽  
Badr R'Mili ◽  
Baptiste Marques ◽  
Brice Temime-Roussel ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Diesel Particulate Filter ◽  
Chemical Reactivity ◽  
Cold Start ◽  
Emission Factors ◽  
Technical Note ◽  
Particulate Filter ◽  
Diesel Particulate ◽  
Light Duty ◽  
Light Duty Vehicles

Abstract. Changes in engine technologies and after-treatment devices can profoundly alter the chemical composition of the emitted pollutants. To investigate these effects, we characterized the chemical composition of particles emitted from three diesel and four gasoline Euro 5 light duty vehicles on a chassis dynamometer facility. Black carbon (BC) was the dominant emitted species with emission factors (EFs) varying from 0.2 to 7.1 mg km−1 for gasoline cars and 0.003 to 0.08 mg km−1 for diesel cars. For gasoline cars, the organic matter (OM) EFs varied from 5 to 103 µg km−1 for direct injection (GDI) vehicles, and from 1 to 8 µg km−1 for port fuel injection (PFI) vehicles, while for the diesel cars it ranged between 0.15 and 65 µg km−1. Cold-start cycles and more specifically the first minutes of the cycle, contributed the largest fraction of the PM including BC, OM and Polycyclic Aromatic Hydrocarbons (PAHs). More than 40 PAHs, including methylated, nitro, oxygenated and amino PAHs were identified and quantified in both diesel and gasoline exhaust particles using an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometry (HR-ToF-AMS). The PAHs emissions from the GDI technology were a factor of 4 higher compared to the vehicles equipped with a PFI system during the cold start cycle, while the nitro-PAHs fraction was much more appreciable in the GDI emissions. For two of the three diesel vehicles the PAHs emissions were close to the detection limit, but for one, which presented an after-treatment device failure, the average PAHs EF was 2.04 µg km−1. Emissions of nanoparticles (below 30 nm), mainly composed by ammonium bisulfate, were measured during the passive regeneration of the catalyzed diesel particulate filter (CDPF) vehicle. TEM images confirmed the presence of ubiquitous nanometric metal inclusions into soot particles emitted from the diesel vehicle equipped with a fuel borne catalyst – diesel particulate filter (FBC-DPF). XPS analysis of the particles emitted by the PFI car revealed both the presence of heavy elements (Ti, Zn, Ca, Si, P, Cl), and disordered soot surface with a significant concentration of carbon radical defects having possible consequences on both chemical reactivity and particle toxicity. Our findings show that different after-treatment technologies have an important effect on the level and the chemical composition of the emitted particles. In addition, this research highlights the importance of the particle filter devices condition and their regular checking.

scholarly journals Technical note: Emission factors, chemical composition, and morphology of particles emitted from Euro 5 diesel and gasoline light-duty vehicles during transient cycles

2021 ◽  
Vol 21 (6) ◽  
pp. 4779-4796
Author(s):  
Evangelia Kostenidou ◽  
Alvaro Martinez-Valiente ◽  
Badr R'Mili ◽  
Baptiste Marques ◽  
Brice Temime-Roussel ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Photoelectron Spectroscopy ◽  
Diesel Particulate Filter ◽  
Chemical Reactivity ◽  
Emission Factors ◽  
Particulate Filter ◽  
Diesel Particulate ◽  
Diesel Vehicles ◽  
Light Duty ◽  
Light Duty Vehicles

Abstract. Changes in engine technologies and after-treatment devices can profoundly alter the chemical composition of the emitted pollutants. To investigate these effects, we characterized the emitted particles' chemical composition of three diesel and four gasoline Euro 5 light-duty vehicles tested at a chassis dynamometer facility. The dominant emitted species was black carbon (BC) with emission factors (EFs) varying from 0.2 to 7.1 mg km−1 for direct-injection gasoline (GDI) vehicles, from 0.02 to 0.14 mg km−1 for port fuel injection (PFI) vehicles, and 0.003 to 0.9 mg km−1 for diesel vehicles. The organic matter (OM) EFs varied from 5 to 103 µg km−1 for GDI gasoline vehicles, from 1 to 8 µg km−1 for PFI vehicles, and between 0.15 and 65 µg km−1 for the diesel vehicles. The first minutes of cold-start cycles contributed the largest PM fraction including BC, OM, and polycyclic aromatic hydrocarbons (PAHs). Using a high-resolution time-of-flight mass spectrometer (HR-ToF-AMS), we identified more than 40 PAHs in both diesel and gasoline exhaust particles including methylated, nitro, oxygenated, and amino PAHs. Particle-bound PAHs were 4 times higher for GDI than for PFI vehicles. For two of the three diesel vehicles the PAH emissions were below the detection limit, but for one, which presented an after-treatment device failure, the average PAHs EF was 2.04 µg km−1, similar to the GDI vehicle's values. During the passive regeneration of the catalysed diesel particulate filter (CDPF) vehicle, we measured particles of diameter around 15 nm mainly composed of ammonium bisulfate. Transmission electron microscopy (TEM) images revealed the presence of ubiquitous metal inclusions in soot particles emitted by the diesel vehicle equipped with a fuel-borne-catalyst diesel particulate filter (FBC-DPF). X-ray photoelectron spectroscopy (XPS) analysis of the particles emitted by the PFI vehicle showed the presence of metallic elements and a disordered soot surface with defects that could have consequences on both chemical reactivity and particle toxicity. Our findings show that different after-treatment technologies have an important effect on the emitted particles' levels and their chemical composition. In addition, this work highlights the importance of particle filter devices' condition and performance.

Effects of B20 on Emissions and the Performance of a Diesel Particulate Filter in a Light-Duty Diesel Engine

2009 ◽  
Author(s):  
Amy M. Peterson ◽  
Po-I Lee ◽  
Ming-Chia Lai ◽  
Ming-Cheng Wu ◽  
Craig L. DiMaggio ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Diesel Particulate Filter ◽  
Oxidation Catalyst ◽  
Engine Oil ◽  
Particulate Filter ◽  
Oil Viscosity ◽  
Regeneration Rate ◽  
Diesel Particulate ◽  
Light Duty ◽  
Active Regeneration

This paper compares 20% bio-diesel (B20-choice white grease) fuel with baseline ultra low sulfur diesel (ULSD) fuel on the emissions and performance of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) coupled to a light-duty 4-cylinder 2.8-liter common-rail DI diesel engine. The present paper focuses on the comparison of the fuel effects on loading and active regeneration of the DPF between B20 and ULSD. B20, in general, produces less soot and has lower regeneration temperature compared to soot loaded with ULSD. NO2 concentrations before the DPF were found to be 6% higher with B20, indicating more availability of NO2 to oxidize the soot. Exhaust speciation of the NO2 availability indicates that the slight increase in NOx from B20 is not the dominant cause for the lower temperature regeneration and faster regeneration rate but the reactivity of the soot that is in the DPF. Formaldehyde concentrations are found to be higher with B20 during regeneration due to increased oxygen concentrations in the exhaust stream. Finally the oil dilution effect due to post injection to actively regenerate the DPF is also investigated using a prototype oil sensor and FTIR instrumentation. Utilizing an active regeneration strategy accentuates the possibility of fuel oil dilution of the engine oil. The onboard viscosity oil sensor used was in good agreement with the viscosity bench test and FTIR analysis and provided oil viscosity measurement over the course of the project. Operation with B20 shows significant fuel dilution and needs to be monitored to prevent engine deterioration.

Effects of B20 on Emissions and the Performance of a Diesel Particulate Filter in a Light-Duty Diesel Engine

2010 ◽  
Vol 132 (11) ◽  
Author(s):  
Amy M. Peterson ◽  
Po-I Lee ◽  
Ming-Chia Lai ◽  
Ming-Cheng Wu ◽  
Craig L. DiMaggio ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Diesel Particulate Filter ◽  
Oxidation Catalyst ◽  
Engine Oil ◽  
Particulate Filter ◽  
Oil Viscosity ◽  
Regeneration Rate ◽  
Diesel Particulate ◽  
Light Duty ◽  
Active Regeneration

This paper compares 20% biodiesel (B20-choice white grease) fuel with baseline ultra low sulfur diesel (ULSD) fuel on the emissions and performance of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) coupled to a light duty four-cylinder 2.8-l common-rail DI diesel engine. The present paper focuses on the comparison of the fuel effects on loading and active regeneration of the DPF between B20 and ULSD. B20, in general, produces less soot and has lower regeneration temperature, compared with soot loaded with ULSD. NO2 concentrations before the DPF were found to be 6% higher with B20, indicating more availability of NO2 to oxidize the soot. Exhaust speciation of the NO2 availability indicates that the slight increase in NOx from B20 is not the dominant cause for the lower temperature regeneration and faster regeneration rate, but the reactivity of the soot that is in the DPF. Formaldehyde concentrations are found to be higher with B20 during regeneration, due to increased oxygen concentrations in the exhaust stream. Finally, the oil dilution effect due to post injection to actively regenerate the DPF is also investigated using a prototype oil sensor and Fourier transform infrared (FTIR) instrumentation. Utilizing an active regeneration strategy accentuates the possibility of fuel oil dilution of the engine oil. The onboard viscosity oil sensor used was in good agreement with the viscosity bench test and FTIR analysis, and provided oil viscosity measurement over the course of the project. The operation with B20 shows significant fuel dilution and needs to be monitored to prevent engine deterioration.

scholarly journals Emission Factors Derived from 13 Euro 6b Light-Duty Vehicles Based on Laboratory and On-Road Measurements

Atmosphere ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 243 ◽  
Author(s):  
Victor Valverde ◽  
Bernat Mora ◽  
Michaël Clairotte ◽  
Jelica Pavlovic ◽  
Ricardo Suarez-Bertoa ◽  
...  
Keyword(s):  
Co2 Emissions ◽  
Particle Number ◽  
Cold Start ◽  
Emission Factors ◽  
Testing Procedures ◽  
Diesel Vehicles ◽  
Type Approval ◽  
Light Duty ◽  
Gasoline Vehicles ◽  
Light Duty Vehicles

Tailpipe emissions of a pool of 13 Euro 6b light-duty vehicles (eight diesel and five gasoline-powered) were measured over an extensive experimental campaign that included laboratory (chassis dynamometer), and on-road tests (using a portable emissions measurement system). The New European Driving Cycle (NEDC) and the Worldwide harmonised Light-duty vehicles Test Cycle (WLTC) were driven in the laboratory following standard and extended testing procedures (such as low temperatures, use of auxiliaries, modified speed trace). On-road tests were conducted in real traffic conditions, within and outside the boundary conditions of the regulated European Real-Driving Emissions (RDE) test. Nitrogen oxides (NOX), particle number (PN), carbon monoxide (CO), total hydrocarbons (HC), and carbon dioxide (CO2) emission factors were developed considering the whole cycles, their sub-cycles, and the first 300 s of each test to assess the cold start effect. Despite complying with the NEDC type approval NOX limit, diesel vehicles emitted, on average, over the WLTC and the RDE 2.1 and 6.7 times more than the standard limit, respectively. Diesel vehicles equipped with only a Lean NOX trap (LNT) averaged six and two times more emissions over the WLTC and the RDE, respectively, than diesel vehicles equipped with a selective catalytic reduction (SCR) catalyst. Gasoline vehicles with direct injection (GDI) emitted eight times more NOX than those with port fuel injection (PFI) on RDE tests. Large NOX emissions on the urban section were also recorded for GDIs (122 mg/km). Diesel particle filters were mounted on all diesel vehicles, resulting in low particle number emission (~1010 #/km) over all testing conditions including low temperature and high dynamicity. GDIs (~1012 #/km) and PFIs (~1011 #/km) had PN emissions that were, on average, two and one order of magnitude higher than for diesel vehicles, respectively, with significant contribution from the cold start. PFIs yielded high CO emission factors under high load operation reaching on average 2.2 g/km and 3.8 g/km on WLTC extra-high and RDE motorway, respectively. The average on-road CO2 emissions were ~33% and 41% higher than the declared CO2 emissions at type-approval for diesel and gasoline vehicles, respectively. The use of auxiliaries (AC and lights on) over the NEDC led to an increase of ~20% of CO2 emissions for both diesel and gasoline vehicles. Results for NOX, CO and CO2 were used to derive average on-road emission factors that are in good agreement with the emission factors proposed by the EMEP/EEA guidebook.

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