On-road mileage-based emission factors of gaseous pollutants from bi-fuel taxi fleets in China: The influence of fuel type, vehicle speed, and accumulated mileage

2021 ◽  
pp. 151999
Author(s):  
Yang Wang ◽  
Zhenyu Xing ◽  
Hongteng Zhang ◽  
Yumo Wang ◽  
Ke Du
Keyword(s):  
Emission Factors ◽  
Gaseous Pollutants ◽  
Vehicle Speed ◽  
Fuel Type

scholarly journals IASI-derived NH<sub>3</sub> enhancement ratios relative to CO for the tropical biomass burning regions

2017 ◽  
Vol 17 (19) ◽  
pp. 12239-12252 ◽  
Author(s):  
Simon Whitburn ◽  
Martin Van Damme ◽  
Lieven Clarisse ◽  
Daniel Hurtmans ◽  
Cathy Clerbaux ◽  
...  
Keyword(s):  
Regional Differences ◽  
Temporal Distribution ◽  
Emission Factors ◽  
Regional Level ◽  
Fuel Type ◽  
Broadleaf Forest ◽  
Tropical Regions ◽  
Airborne Measurements ◽  
Vegetation Fires ◽  
Good Agreement

Abstract. Vegetation fires are a major source of ammonia (NH3) in the atmosphere. Their emissions are mainly estimated using bottom-up approaches that rely on uncertain emission factors. In this study, we derive new biome-specific NH3 enhancement ratios relative to carbon monoxide (CO), ERNH3 ∕ CO (directly related to the emission factors), from the measurements of the IASI sounder onboard the Metop-A satellite. This is achieved for large tropical regions and for an 8-year period (2008–2015). We find substantial differences in the ERNH3 ∕ CO ratios between the biomes studied, with calculated values ranging from 7  ×  10−3 to 23  ×  10−3. For evergreen broadleaf forest these are typically 50–75 % higher than for woody savanna and savanna biomes. This variability is attributed to differences in fuel types and size and is in line with previous studies. The analysis of the spatial and temporal distribution of the ERNH3 ∕ CO ratio also reveals a (sometimes large) within-biome variability. On a regional level, woody savanna shows, for example, a mean ERNH3 ∕ CO ratio for the region of Africa south of the Equator that is 40–75 % lower than in the other five regions studied, probably reflecting regional differences in fuel type and burning conditions. The same variability is also observed on a yearly basis, with a peak in the ERNH3 ∕ CO ratio observed for the year 2010 for all biomes. These results highlight the need for the development of dynamic emission factors that take into better account local variations in fuel type and fire conditions. We also compare the IASI-derived ERNH3 ∕ CO ratio with values reported in the literature, usually calculated from ground-based or airborne measurements. We find general good agreement in the referenced ERNH3 ∕ CO ratio except for cropland, for which the ERNH3 ∕ CO ratio shows an underestimation of about 2–2.5 times.

Experimental Research on Influence of Vehicle Running Conditions on Emissions

2012 ◽  
Vol 482-484 ◽  
pp. 173-178
Author(s):  
Wen Wei Huang ◽  
Qiang Zhang ◽  
Long Lin Sun ◽  
Mou Rong Gao
Keyword(s):  
High Speed ◽  
Emission Factors ◽  
Measurement Unit ◽  
Emission Characteristics ◽  
Vehicle Speed ◽  
Variable Rate ◽  
Low Speed ◽  
Inflection Points ◽  
Secondary City ◽  
Engine Capacity

Experiments were done to the same car with engine capacity of 1.6 liter on three typical road conditions in Shenzhen for emission characteristics of CO、HC and NOx with SEMTECH-DS manufactured by Sensors Company in USA. Through analysis on the experimental data it is indicated that emission factors with the measurement unit of g/km produced inflection points at the vehicle speed of 7.5～10 Km/h, and its variable rate is big at low speed interval and stable at high speed interval; average emission factors of CO and HC for car running in secondary city main roads is two or five times than those in city main roads; emissions of CO and HC of car at idle and low speed conditions take higher proportion.

scholarly journals Well-to-Wheels Approach for the Environmental Impact Assessment of Road Freight Services

2018 ◽  
Vol 10 (12) ◽  
pp. 4487 ◽  
Author(s):  
Jose Luis Osorio-Tejada ◽  
Eva Llera-Sastresa ◽  
Ahmad Hariza Hashim
Keyword(s):  
Road Transport ◽  
Emission Factors ◽  
Environmental Accounting ◽  
Operating Conditions ◽  
Vehicle Speed ◽  
Industrialized Countries ◽  
Heavy Vehicles ◽  
Fuel Production ◽  
Accounting Systems ◽  
Road Gradient

The diffuse nature of road transport and the heterogeneity of heavy vehicles have hindered the implementation of emissions accounting systems. Even though there are emission factors in well-known databases, these factors have commonly been designed in industrialized countries, which might have geography, type of roads, and operating conditions different to other countries. This paper proposes a method for the energy consumption and emissions estimation based on vehicle operating conditions in regions with different topology, such as Colombia, Malaysia, and Spain, as case studies. Moreover, the environmental impacts of fuel production in each country are calculated. The diesel consumption on mountainous roads for a full loaded rigid truck in Colombia was 45 L/100 km, compared to averages between 22–26 L/100 km from other sources usually applied. In contrast, the diesel consumption for an articulated truck on a hilly road in Spain from both the proposed method and generic databases coincided in 31 L/100 km. The vehicle speed, load, and road gradient also generated large variations up to 145% in the air pollutants’ estimation. This study contributes to the need for more research about emission factors and tools that facilitate and reduce uncertainty in the environmental accounting in freight companies in different geographies.

scholarly journals IASI-derived NH<sub>3</sub> enhancement ratios relative to CO for the tropical biomass burning regions

2017 ◽  
Author(s):  
Simon Whitburn ◽  
Martin Van Damme ◽  
Lieven Clarisse ◽  
Daniel Hurtmans ◽  
Cathy Clerbaux ◽  
...  
Keyword(s):  
Regional Differences ◽  
Temporal Distribution ◽  
Emission Factors ◽  
Regional Level ◽  
The Other ◽  
Fuel Type ◽  
Broadleaf Forest ◽  
Tropical Regions ◽  
Airborne Measurements ◽  
Vegetation Fires

Abstract. Vegetation fires are a major source of ammonia (NH3) in the atmosphere. Their emissions are mainly estimated from bottom-up approaches which rely on uncertain emission factors. In this study, we derive new biome-specific NH3 enhancement ratios relative to carbon monoxide (CO), ERNH3/CO – directly related to the emission factors, from the measurements of the IASI sounder on board the Metop-A satellite. This is achieved for large tropical regions and for a 8-year period (2008–2015). We find substantial differences in the ERNH3/CO between the studied biomes with calculated values ranging from 4.4 × 10−3 to 17 × 10−3. For Evergreen Broadleaf Forest these are typically 75–100 % higher than for Woody Savanna and Savanna biomes. This variability is attributed to differences in fuel types and size and is in line with previous studies. The analysis of the spatial and temporal distribution of the ERNH3/CO also reveals a (sometimes large) within-biome variability. On a regional level, Woody Savanna shows for example a mean ERNH3/CO for the region of Africa South of the Equator which is 50–100 % lower than in the other five studied regions, probably reflecting regional differences in fuel type and burning conditions. The same variability is also observed on a yearly basis with a peak in the ERNH3/CO observed for the year 2010 for all biomes. These results highlight the need for the development of dynamic emission factors that better take into account local variations in fuel type and fire conditions. We also compare the IASI-derived ERNH3/CO with values reported in the literature, usually calculated from ground-based or airborne measurements. We find a general underestimation over the referenced ERNH3/CO of about 40 % for Woody Savanna and Savanna and up to a factor 1.5–4 for Evergreen Broadleaf Forest and Cropland. Beyond a possible overestimation of the ERNH3/CO in the literature, the observed differences could also be related to various factors including instrumental limits, bias in the retrieval of the NH3 columns, parameterization in the calculation of the ERNH3/CO or accumulation of CO in the studied regions during the fire period.

scholarly journals Biomass burning aerosol emissions from vegetation fires: particle number and mass emission factors and size distributions

2009 ◽  
Vol 9 (4) ◽  
pp. 17183-17217 ◽  
Author(s):  
S. Janhäll ◽  
M. O. Andreae ◽  
U. Pöschl
Keyword(s):  
Particle Number ◽  
Combustion Efficiency ◽  
Emission Factors ◽  
Fuel Type ◽  
Vegetation Fires ◽  
Fitting Procedures ◽  
Median Diameter ◽  
Count Median Diameter ◽  
Biomass Burning Aerosol ◽  
Aerosol Emissions

Abstract. Aerosol emissions from vegetation fires have a large impact on air quality and climate. In this study, we use published experimental data and different fitting procedures to derive dynamic particle number and mass emission factors (EFPN, EFPM) related to the fuel type, burning conditions and the mass of dry fuel burned, as well as characteristic CO-referenced emission ratios (PN/CO, PM/CO). Moreover, we explore and characterize the variability of the particle size distribution of fresh smoke, which is typically dominated by a lognormal accumulation mode with count median diameter around 120 nm (depending on age, fuel and combustion efficiency), and its effect on the relationship between particle number and mass emission factors. For the particle number emission factor of vegetation fires, we found no dependence on fuel type and obtained the following parameterization as a function of modified combustion efficiency (MCE): EFPN=34·1015×(1-MCE) kg−1±1015 kg−1 with regard to dry fuel mass (d.m.). For the fine particle mass emission factors (EFPM) we obtained (86–85×MCE) g kg−1±3 g kg−1 as an average for all investigated fires; (93–90×MCE) g kg

scholarly journals Developing On-Road NOx Emission Factors for Euro 6b Light-Duty Diesel Trucks in Korean Driving Conditions

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1041
Author(s):  
Seungcheon Ro ◽  
Junhong Park ◽  
Myunghwan Shin ◽  
Jongtae Lee
Keyword(s):  
Nox Reduction ◽  
Emission Factors ◽  
Nox Emission ◽  
Lean Nox Trap ◽  
Vehicle Speed ◽  
Light Duty ◽  
Lean Nox ◽  
Wide Variability ◽  
Driving Conditions ◽  
Diesel Trucks

This study aimed to develop on-road NOx emission factors for Euro 6b light-duty diesel trucks (LDDTs) in Korea. On-road NOx emissions were measured using portable emissions measurement systems and compared with those measured using the Korean Driving Cycle (KDC), the conventional laboratory test used to develop emission factors. To ensure the representativeness of the LDDTs emission factors, five vehicles of three models were driven along two real driving routes for total traveled mileage of 2280 km. On-road NOx levels were 2.1 to 6.9 times higher on average than those measured using the KDC because the latter does not cover the wide variability in vehicle speed and relative positive acceleration, common in real driving conditions. The lean-NOx trap was found to have disappointingly low NOx reduction efficiency in on-road driving. The on-road NOx emission factors by vehicle speeds developed in this study were comparable to the COPERT 4 factors.

Emission factors of gaseous pollutants from small scale combustion of biofuels

Fuel ◽  
2016 ◽  
Vol 165 ◽  
pp. 68-74 ◽  
Author(s):  
Jan Hrdlička ◽  
Pavel Skopec ◽  
Tomáš Dlouhý ◽  
František Hrdlička
Keyword(s):  
Emission Factors ◽  
Small Scale ◽  
Gaseous Pollutants
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