Exhaust Aftertreatment for Diesel Vehicles*

Abstract. Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the final vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC<0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23–0.56 g/kg fuel burned. In presence of both a DOC and a DPF, primary particles with a mobility diameter above 5 nm were 300±19 cm−3, and only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.097 to 0.190. Five hours of oxidation led to a more oxidized OA with an O/C range of 0.208 to 0.369.

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Impact of aftertreatment devices on primary emissions and secondary organic aerosol formation potential from in-use diesel vehicles: results from smog chamber experiments

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-11545-2010 ◽

2010 ◽

Vol 10 (23) ◽

pp. 11545-11563 ◽

Cited By ~ 139

Author(s):

R. Chirico ◽

P. F. DeCarlo ◽

M. F. Heringa ◽

T. Tritscher ◽

R. Richter ◽

...

Keyword(s):

Urban Areas ◽

Secondary Organic Aerosol ◽

Organic Aerosol ◽

Oxidation Catalyst ◽

Particulate Filter ◽

Exhaust Aftertreatment ◽

Smog Chamber ◽

Aerosol Formation ◽

Diesel Particulate ◽

Diesel Vehicles

Abstract. Diesel particulate matter (DPM) is a significant source of aerosol in urban areas and has been linked to adverse health effects. Although newer European directives have introduced increasingly stringent standards for primary PM emissions, gaseous organics emitted from diesel cars can still lead to large amounts of secondary organic aerosol (SOA) in the atmosphere. Here we present results from smog chamber investigations characterizing the primary organic aerosol (POA) and the corresponding SOA formation at atmospherically relevant concentrations for three in-use diesel vehicles with different exhaust aftertreatment systems. One vehicle lacked exhaust aftertreatment devices, one vehicle was equipped with a diesel oxidation catalyst (DOC) and the third vehicle used both a DOC and diesel particulate filter (DPF). The experiments presented here were obtained from the vehicles at conditions representative of idle mode, and for one car in addition at a speed of 60 km/h. An Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was used to measure the organic aerosol (OA) concentration and to obtain information on the chemical composition. For the conditions explored in this paper, primary aerosols from vehicles without a particulate filter consisted mainly of black carbon (BC) with a low fraction of organic matter (OM, OM/BC < 0.5), while the subsequent aging by photooxidation resulted in a consistent production of SOA only for the vehicles without a DOC and with a deactivated DOC. After 5 h of aging ~80% of the total organic aerosol was on average secondary and the estimated "emission factor" for SOA was 0.23–0.56 g/kg fuel burned. In presence of both a DOC and a DPF, only 0.01 g SOA per kg fuel burned was produced within 5 h after lights on. The mass spectra indicate that POA was mostly a non-oxidized OA with an oxygen to carbon atomic ratio (O/C) ranging from 0.10 to 0.19. Five hours of oxidation led to a more oxidized OA with an O/C range of 0.21 to 0.37.

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RESEARCH OF INDICATORS OF A VEHICLE WITH A DIESEL WORKING ON DIESEL AND DIESEL GAS CYCLES USING THE MATHEMATICAL MODEL

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2020-1-261-14-19 ◽

2020 ◽

pp. 14-19

Author(s):

Serhii Kovbasenko ◽

Andriy Holyk ◽

Serhii Hutarevych

Keyword(s):

Mathematical Model ◽

Diesel Engine ◽

Environmental Performance ◽

Energy Performance ◽

Dual Fuel ◽

Fuel System ◽

Compressed Natural Gas ◽

Diesel Vehicles ◽

Diesel Cycle ◽

The Mathematical Model

The features of an advanced mathematical model of motion of a truck with a diesel engine operating on the diesel and diesel gas cycles are presented in the article. As a result of calculations using the mathematical model, a decrease in total mass emissions as a result of carbon monoxide emissions is observed due to a decrease in emissions of nitrogen oxides and emissions of soot in the diesel gas cycle compared to the diesel cycle. The mathematical model of a motion of a truck on a city driving cycle according to GOST 20306-90 allows to study the fuel-economic, environmental and energy indicators of a diesel and diesel gas vehicle. The results of the calculations on the mathematical model will make it possible to conclude on the feasibility of converting diesel vehicles to using compressed natural gas. Object of the study – the fuel-economic, environmental and energy performance diesel engine that runs on dual fuel system using CNG. Purpose of the study – study of changes in fuel, economic, environmental and energy performance of vehicles with diesel engines operating on diesel and diesel gas cycles, according to urban driving cycle modes. Method of the study – calculations on a mathematical model and comparison of results with road tests. Bench and road tests, results of calculations on the mathematical model of motion of a truck with diesel, working on diesel and diesel gas cycles, show the improvement of environmental performance of diesel vehicles during the converting to compressed natural gas in operation. Improvement of environmental performance is obtained mainly through the reduction of soot emissions and nitrogen oxides emissions from diesel gas cycle operations compared to diesel cycle operations. The results of the article can be used to further develop dual fuel system using CNG. Keywords: diesel engine, diesel gas engine, CNG

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SMOKE EMISSIONS FROM DIESEL VEHICLES: A CASE STUDY

Environmental Engineering and Management Journal ◽

10.30638/eemj.2008.018 ◽

2008 ◽

Vol 7 (2) ◽

pp. 103-110

Author(s):

Mishra Rajeev Kumar ◽

Pandey Govind ◽

Manoranjan Parida

Keyword(s):

Diesel Vehicles

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Effects of renewable fuel and exhaust aftertreatment on primary and secondary emissions from a modern heavy-duty diesel engine

Journal of Aerosol Science ◽

10.1016/j.jaerosci.2021.105781 ◽

2021 ◽

Vol 156 ◽

pp. 105781

Author(s):

Louise Gren ◽

Vilhelm B. Malmborg ◽

John Falk ◽

Lassi Markula ◽

Maja Novakovic ◽

...

Keyword(s):

Diesel Engine ◽

Exhaust Aftertreatment ◽

Heavy Duty ◽

Renewable Fuel ◽

Heavy Duty Diesel Engine ◽

Heavy Duty Diesel

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A Study of Prediction Based on Regression Analysis for Real-World Co2 Emissions with Light-Duty Diesel Vehicles

International Journal of Automotive Technology ◽

10.1007/s12239-021-0053-z ◽

2021 ◽

Vol 22 (3) ◽

pp. 569-577

Author(s):

Junepyo Cha ◽

Junhong Park ◽

Hyoungwook Lee ◽

Mun Soo Chon

Keyword(s):

Regression Analysis ◽

Co2 Emissions ◽

Real World ◽

Diesel Vehicles ◽

Light Duty

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Organic aerosol source apportionment in London 2013 with ME-2: exploring the solution space with annual and seasonal analysis

Atmospheric Chemistry and Physics ◽

10.5194/acp-16-15545-2016 ◽

2016 ◽

Vol 16 (24) ◽

pp. 15545-15559 ◽

Cited By ~ 12

Author(s):

Ernesto Reyes-Villegas ◽

David C. Green ◽

Max Priestman ◽

Francesco Canonaco ◽

Hugh Coe ◽

...

Keyword(s):

Source Apportionment ◽

Statistical Tests ◽

Solution Space ◽

Organic Aerosol ◽

Data Sets ◽

Environmental Implications ◽

Data Set ◽

Diesel Vehicles ◽

Heavy Duty Diesel ◽

Paul Scherrer

Abstract. The multilinear engine (ME-2) factorization tool is being widely used following the recent development of the Source Finder (SoFi) interface at the Paul Scherrer Institute. However, the success of this tool, when using the a value approach, largely depends on the inputs (i.e. target profiles) applied as well as the experience of the user. A strategy to explore the solution space is proposed, in which the solution that best describes the organic aerosol (OA) sources is determined according to the systematic application of predefined statistical tests. This includes trilinear regression, which proves to be a useful tool for comparing different ME-2 solutions. Aerosol Chemical Speciation Monitor (ACSM) measurements were carried out at the urban background site of North Kensington, London from March to December 2013, where for the first time the behaviour of OA sources and their possible environmental implications were studied using an ACSM. Five OA sources were identified: biomass burning OA (BBOA), hydrocarbon-like OA (HOA), cooking OA (COA), semivolatile oxygenated OA (SVOOA) and low-volatility oxygenated OA (LVOOA). ME-2 analysis of the seasonal data sets (spring, summer and autumn) showed a higher variability in the OA sources that was not detected in the combined March–December data set; this variability was explored with the triangle plots f44 : f43 f44 : f60, in which a high variation of SVOOA relative to LVOOA was observed in the f44 : f43 analysis. Hence, it was possible to conclude that, when performing source apportionment to long-term measurements, important information may be lost and this analysis should be done to short periods of time, such as seasonally. Further analysis on the atmospheric implications of these OA sources was carried out, identifying evidence of the possible contribution of heavy-duty diesel vehicles to air pollution during weekdays compared to those fuelled by petrol.

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Effect of Butanol on the Performance of DeNOx Aftertreatment Systems of a Diesel Vehicle Under WLTC Driving Conditions

10.1115/icef2021-67337 ◽

2021 ◽

Author(s):

Alejandro Calle-Asensio ◽

Juan José Hernández ◽

José Rodríguez-Fernández ◽

Víctor Domínguez-Pérez

Keyword(s):

Catalytic Reduction ◽

Nox Reduction ◽

Climatic Conditions ◽

Transport Sector ◽

Lean Nox Trap ◽

Diesel Vehicles ◽

Medium Speed ◽

Emission Regulations ◽

Lean Nox ◽

Light Duty Vehicles

Abstract Advanced biofuels and electrofuels, among which are medium-long chain alcohols, have gained importance in the transport sector with the enforcement of the EU Renewable Energy Directive (2018/2001). In parallel, last European emission regulations have become much more restrictive regarding NOx, so vehicle manufacturers have been forced to incorporate lean NOx trap (LNT) and/or selective catalytic reduction (SCR). Thus, the combination of modern DeNOx devices and the upcoming higher contribution of sustainable biofuels is a new challenge. In this work, two Euro 6 diesel vehicles, one equipped with LNT and the other with ammonia-SCR, have been tested following the Worldwide harmonized Light-duty vehicles Test Cycle (WLTC) at warm (24°C) and cold (−7°C) conditions using conventional diesel fuel and a diesel-butanol (90/10% vol.) blend. While the effect of butanol on the LNT efficiency was not significant, its influence on the SCR performance was notable during the low and medium-speed phases of the driving cycle, mainly under warm climatic conditions. Despite of the lower NOx concentration at the catalyst inlet, the worst efficiency of the SCR with butanol could be attributed to hydrocarbons deposition on the catalyst surface, which inhibits the NOx reduction reactions with ammonia. Moreover, the LNT was not sensitive to the ambient temperature while the SCR performance greatly depended on this parameter.

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