Towards the ranking of airborne particle emissions from car brakes – a system approach

Airborne particulate matter emitted from motor vehicle brakes is a contributor to urban air quality. Therefore, a method to rank brake pairs (pads and rotors) with respect to their particle emission factors in a reliable way is needed to develop a low-emission disc brake. A novel inertial disc brake dynamometer designed for brake particle emission studies, a modified SAE J 2707 cycle, an electrical low-pressure cascade impactor and a filter are used to test five different pad materials against cast-iron rotors. By changing only the pad materials, it is shown that the differences between the mass emission factor and the number emission factor of the the worst brake pair and those of the best brake pair decreases by more than four times and 19 times respectively. Furthermore, the results show that the material combination ranked the best in terms of the mass emission factor is ranked the worst in terms of the number emission factor. The results reveal that this combination of a test stand, a test cycle and particle instruments can discriminate between different brake pair materials in a reliable way in the case of the mass emission factors while more research has to be carried out in the case of the number emission factors.

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A proposed driving cycle for brake emissions investigation for test stand

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

10.1177/0954407019841222 ◽

2019 ◽

Vol 234 (1) ◽

pp. 122-135 ◽

Cited By ~ 8

Author(s):

Guido Perricone ◽

Mattia Alemani ◽

Jens Wahlström ◽

Ulf Olofsson

Keyword(s):

Particulate Matter ◽

Particle Number ◽

Emission Factors ◽

Particle Emission ◽

Test Stand ◽

Disc Brake ◽

Test Cycle ◽

Particulate Matter Emission ◽

Brake Dynamometer ◽

Emission Studies

Particulate matter emission factors from vehicle brakes are difficult to assess directly from the field. Moreover, there is a lack of a standardized cycle and test stand for evaluating brake emissions. For these reasons, a test cycle was developed from real driving data collected from a car. This new test cycle was implemented on an inertia disc brake dynamometer appositely designed for brake particle emission studies. Results reveal that, for the brake system used as an example, the obtained emission factors for the urban driving conditions studied are comparable to EURO 6 regulations in terms of particle number and comparable to EURO 4 levels in terms of mass with brake emission factors equal to 4.37–6.46 × 1011 particles/km and 44–48 mg/km, respectively.

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Derivation of motor vehicle tailpipe particle emission factors suitable for modelling urban fleet emissions and air quality assessments

Environmental Science and Pollution Research ◽

10.1007/s11356-009-0210-9 ◽

2009 ◽

Vol 17 (3) ◽

pp. 724-739 ◽

Cited By ~ 22

Author(s):

Diane U. Keogh ◽

Joe Kelly ◽

Kerrie Mengersen ◽

Rohan Jayaratne ◽

Luis Ferreira ◽

...

Keyword(s):

Air Quality ◽

Motor Vehicle ◽

Emission Factors ◽

Particle Emission ◽

Quality Assessments

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Assessment of Different Methods in Analyzing Motor Vehicle Emission Factors

10.21203/rs.3.rs-165631/v1 ◽

2021 ◽

Author(s):

Chengkang Gao ◽

Hong-ming Na ◽

Kaihui Song ◽

Qing-jiang Xu

Keyword(s):

Emission Factor ◽

Motor Vehicle ◽

Geographic Location ◽

Emission Factors ◽

Operating Conditions ◽

Motor Vehicles ◽

Vehicle Emission ◽

Emission Standard ◽

Actual Measurement ◽

Ive Model

Abstract To explore the emission characteristics of vehicle’s pollutants is of great significance to prevent and control the diffusion of pollutants. Limited by geographic location and economic condition, the models- and guidelines-based studies on vehicle’s emission factor have become more concerned measures than the actual measurement. By analyzing the actual operating conditions of motor vehicles, this study obtain the emission factors of typical pollutants from different motor vehicles by adopting international vehicle emission (IVE) model and guideline method, respectively. Furthermore, the resulting emission factors by the above methods were compared and analyzed with on-road method. The results show that: (1) the emission factors of vehicle pollutants change regularly with velocity, emission standard and accumulated mileage. Taking CO as an example, its emission factor shows a downward trend with the increase of velocity and emission standard, and an upward trend with the increase of accumulated mileage; (2) Compared with the actual measurement, the vehicle emission factor obtained by the guideline method has a large error, while the IVE model is close to the actual.

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Major Elements to Consider in Developing Ammonia Emission Factor at Municipal Solid Waste (MSW) Incinerators

Sustainability ◽

10.3390/su13042197 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2197

Author(s):

Seongmin Kang ◽

Joonyoung Roh ◽

Eui-chan Jeon

Keyword(s):

Municipal Solid Waste ◽

Solid Waste ◽

Emission Factor ◽

Waste Incineration ◽

Emission Factors ◽

Major Elements ◽

Ammonia Emission ◽

Nh3 Emission ◽

The Difference ◽

The One

NH3 is one of the major substances contributing to the secondary generation of PM2.5; therefore, management is required. In Korea, the management of NH3 is insufficient, and the emission factor used by EPA is the same as the one used when calculating emissions. In particular, waste incineration facilities do not currently calculate NH3 emissions. In the case of combustion facilities, the main ammonia emission source is the De-NOx facility, and, in the case of a power plant with a De-NOx facility, NH3 emission is calculated. Therefore, in the case of a Municipal Solid Waste (MSW) incinerator with the same facility installed, it is necessary to calculate NH3 emissions. In this study, the necessity of developing NH3 emission factors for an MSW incinerator and calculating emission was analyzed. In addition, elements to be considered when developing emission factors were analyzed. The study found that the NH3 emission factors for each MSW incinerator technology were calculated as Stoker 0.010 NH3 kg/ton and Fluidized Beds 0.004 NH3 kg/ton, which was greater than the NH3 emission factor 0.003 NH3 kg/ton for the MSW incinerator presented in EMEP/EEA (2016). As a result, it was able to identify the need for the development of NH3 emission factors in MSW incinerators in Korea. In addition, the statistical analysis of the difference between the incineration technology of MSW and the NH3 emission factor by the De-NOx facility showed a difference in terms of both incineration technology and De-NOx facilities, indicating that they should be considered together when developing the emission factor. In addition to MSW, it is believed that it will be necessary to review the development of emission factors for waste at workplaces and incineration facilities of sewage sludge.

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Wind tunnel modeling of atmospheric emissions from agricultural burning: influence of operating configuration on flame structure and particle emission factor for a spreading-type fire

Environmental Science & Technology ◽

10.1021/es00046a002 ◽

1993 ◽

Vol 27 (9) ◽

pp. 1763-1775 ◽

Cited By ~ 11

Author(s):

Bryan M. Jenkins ◽

Ian M. Kennedy ◽

Scott Q. Turn ◽

Robert B. Williams ◽

Steven G. Hall ◽

...

Keyword(s):

Wind Tunnel ◽

Emission Factor ◽

Flame Structure ◽

Particle Emission ◽

Atmospheric Emissions ◽

Agricultural Burning

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Groundwater N<sub>2</sub>O emission factors of nitrate-contaminated aquifers as derived from denitrification progress and N<sub>2</sub>O accumulation

Biogeosciences ◽

10.5194/bg-5-1215-2008 ◽

2008 ◽

Vol 5 (5) ◽

pp. 1215-1226 ◽

Cited By ~ 61

Author(s):

D. Weymann ◽

R. Well ◽

H. Flessa ◽

C. von der Heide ◽

M. Deurer ◽

...

Keyword(s):

Emission Factor ◽

Noble Gas ◽

N2o Emission ◽

Emission Factors ◽

N2o Emissions ◽

Northern Germany ◽

Stable Component ◽

Sand And Gravel ◽

First Time ◽

Ipcc Default

Abstract. We investigated the dynamics of denitrification and nitrous oxide (N2O) accumulation in 4 nitrate (NO−3) contaminated denitrifying sand and gravel aquifers of northern Germany (Fuhrberg, Sulingen, Thülsfelde and Göttingen) to quantify their potential N2O emission and to evaluate existing concepts of N2O emission factors. Excess N2 – N2 produced by denitrification – was determined by using the argon (Ar) concentration in groundwater as a natural inert tracer, assuming that this noble gas functions as a stable component and does not change during denitrification. Furthermore, initial NO−3 concentrations (NO−3 that enters the groundwater) were derived from excess N2 and actual NO−3 concentrations in groundwater in order to determine potential indirect N2O emissions as a function of the N input. Median concentrations of N2O and excess N2 ranged from 3 to 89 μg N L−1 and from 3 to 10 mg N L−1, respectively. Reaction progress (RP) of denitrification was determined as the ratio between products (N2O-N + excess N2) and starting material (initial NO−3 concentration) of the process, characterizing the different stages of denitrification. N2O concentrations were lowest at RP close to 0 and RP close to 1 but relatively high at a RP between 0.2 and 0.6. For the first time, we report groundwater N2O emission factors consisting of the ratio between N2O-N and initial NO−3-N concentrations (EF1). In addition, we determined a groundwater emission factor (EF2) using a previous concept consisting of the ratio between N2O-N and actual NO−3-N concentrations. Depending on RP, EF(1) resulted in smaller values compared to EF(2), demonstrating (i) the relevance of NO−3 consumption and consequently (ii) the need to take initial NO−3-N concentrations into account. In general, both evaluated emission factors were highly variable within and among the aquifers. The site medians ranged between 0.00043–0.00438 for EF(1) and 0.00092–0.01801 for EF(2), respectively. For the aquifers of Fuhrberg and Sulingen, we found EF(1) median values which are close to the 2006 IPCC default value of 0.0025. In contrast, we determined significant lower EF values for the aquifers of Thülsfelde and Göttingen. Summing the results up, our study supports the substantial downward revision of the IPCC default EF5-g from 0.015 (1997) to 0.0025 (2006).

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