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Sample records for 98-default emission factors

  1. 40 CFR Table W - 4 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Underground Natural Gas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false 4 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage W Table W Protection of... of Part 98—Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage...

  2. 40 CFR Table W - 2 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false 2 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing W Table W Protection of... of Part 98—Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing...

  3. 40 CFR Table W - 4 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Underground Natural Gas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false 4 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage W Table W Protection of... of Part 98—Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage...

  4. 40 CFR Table W - 2 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false 2 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing W Table W Protection of... of Part 98—Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing...

  5. 40 CFR Table W - 3 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false 3 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Transmission Compression W Table W Protection...-3 of Subpart W of Part 98—Default Total Hydrocarbon Emission Factors for Onshore Natural...

  6. 40 CFR Table W - 3 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false 3 of Subpart W of Part 98-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Transmission Compression W Table W Protection...-3 of Subpart W of Part 98—Default Total Hydrocarbon Emission Factors for Onshore Natural...

  7. 40 CFR Table W - 6 of Subpart W of Part 98-Default Methane Emission Factors for LNG Import and Export Equipment

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false 6 of Subpart W of Part 98-Default Methane Emission Factors for LNG Import and Export Equipment W Table W Protection of Environment...—Default Methane Emission Factors for LNG Import and Export Equipment LNG import and export...

  8. 40 CFR Table W - 6 of Subpart W of Part 98-Default Methane Emission Factors for LNG Import and Export Equipment

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false 6 of Subpart W of Part 98-Default Methane Emission Factors for LNG Import and Export Equipment W Table W Protection of Environment...—Default Methane Emission Factors for LNG Import and Export Equipment LNG import and export...

  9. 40 CFR Table W - 7 of Subpart W of Part 98-Default Methane Emission Factors for Natural Gas Distribution

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 0.772 Open-ended Line 26.131 Population Emission Factors—Below Grade Metering-Regulating station 1..., Inlet Pressure 100 to 300 psig 0.20 Below Grade M&R Station, Inlet Pressure Population....13 Cast Iron 27.25 Population Emission Factors—Distribution Services, Gas Service 4 Unprotected...

  10. 40 CFR Table W - 7 of Subpart W of Part 98-Default Methane Emission Factors for Natural Gas Distribution

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 0.772 Open-ended Line 26.131 Population Emission Factors—Below Grade Metering-Regulating station 1..., Inlet Pressure 100 to 300 psig 0.20 Below Grade M&R Station, Inlet Pressure Population....13 Cast Iron 27.25 Population Emission Factors—Distribution Services, Gas Service 4 Unprotected...

  11. 40 CFR Table I-8 to Subpart I - Table I-8 to Subpart I of Part 98-Table I-8 to Subpart I of Part 98-Default Emission Factors (1...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Table I-8 to Subpart I of Part 98-Table I-8 to Subpart I of Part 98-Default Emission Factors (1-UN2O j) for N2O Utilization (UN2O j) I... Emission Factors (1-UN 2 O j) for N2O Utilization (UN2 O j) Process type factors N2O CVD 1-Ui 0.8...

  12. 40 CFR Table W - 5 of Subpart W of Part 98-Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Methane Emission Factors for Liquefied Natural Gas (LNG) Storage W Table W Protection of Environment... Petroleum and Natural Gas Systems Definitions. Pt. 98, Subpt. W, Table W-5 Table W-5 of Subpart W of Part 98—Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage LNG storage Emission factor...

  13. 40 CFR Table W - 5 of Subpart W of Part 98-Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Methane Emission Factors for Liquefied Natural Gas (LNG) Storage W Table W Protection of Environment... Petroleum and Natural Gas Systems Definitions. Pt. 98, Subpt. W, Table W-5 Table W-5 of Subpart W of Part 98—Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage LNG storage Emission factor...

  14. 40 CFR Table W - 1A of Subpart W of Part 98-Default Whole Gas Emission Factors for Onshore Petroleum and Natural...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Onshore petroleum andnatural gas production Emission factor (scf/hour/component) Eastern U.S. Population... Device Vents 2 37.3 Intermittent Bleed Pneumatic Device Vents 2 13.5 Pneumatic Pumps 3 13.3 Population... Line 0.05 Pump 0.01 Other 5 0.30 Population Emission Factors—All Components, Heavy Crude Service...

  15. 40 CFR Table W - 1A of Subpart W of Part 98-Default Whole Gas Emission Factors for Onshore Petroleum and Natural...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Onshore petroleum andnatural gas production Emission factor (scf/hour/component) Eastern U.S. Population... Device Vents 2 37.3 Intermittent Bleed Pneumatic Device Vents 2 13.5 Pneumatic Pumps 3 13.3 Population... Line 0.05 Pump 0.01 Other 5 0.30 Population Emission Factors—All Components, Heavy Crude Service...

  16. 40 CFR Table I-7 to Subpart I - Table I-7 to Subpart I of Part 98-Table I-7 to Subpart I of Part 98-Default Emission Factors (1...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... i CF4 C2F6 CHF3 CH2F2 C3F8 c-C4F8 NF3 Remote NF3 SF6 Etch 1-Ui 0.7 0.4 0.4 NA NA 0.2 NA NA 0.4 Etch BCF4 NA 0.2 NA NA NA 0.1 NA NA NA Etch BC2F6 NA NA NA NA NA 0.1 NA NA NA CVD 1-Ui NA 0.6 NA NA 0.1...

  17. 40 CFR Table I-5 to Subpart I - Table I-5 to Subpart I of Part 98-Table I-5 to Subpart I of Part 98-Default Emission Factors (1...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas i CF4 C2F6 CHF3 CH2F2 C3F8 c-C4F8 NF3 Remote NF3 SF6 C4F6a C5F8a C4F8Oa Etch 1-Ui 0.7 1 0.4 1 0.4 1 0.06 NA 1 0.2 NA 0.2 0.2 0.1 0.2 NA Etch BCF4 NA 1 0.4 1 0.07 1 0.08 NA 0.2 NA NA NA 1 0.3 0.2 NA Etch BC2F6 NA NA NA NA NA 0.2 NA NA NA 1 0.2 0.2 NA CVD 1-Ui 0.9 0.6 NA NA 0.4 0.1 0.02 0.2 NA NA 0.1...

  18. 40 CFR Table I-6 to Subpart I - Table I-6 to Subpart I of Part 98-Table I-6 to Subpart I of Part 98-Default Emission Factors (1...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... i CF4 C2F6 CHF3 CH2F2 C3F8 c-C4F8 NF3 Remote NF3 SF6 Etch 1-Ui 0.6 NA 0.2 NA NA 0.1 NA NA 0.3 Etch BCF4 NA NA 0.07 NA NA 0.009 NA NA NA Etch BCHF3 NA NA NA NA NA 0.02 NA NA NA Etch BC2F6 NA NA 0.05...

  19. Quantification of Emission Factor Uncertainty

    EPA Science Inventory

    Emissions factors are important for estimating and characterizing emissions from sources of air pollution. There is no quantitative indication of uncertainty for these emission factors, most factors do not have an adequate data set to compute uncertainty, and it is very difficult...

  20. Emission factors for passenger cars: application of instantaneous emission modeling

    NASA Astrophysics Data System (ADS)

    de Haan, Peter; Keller, Mario

    This paper discusses the use of 'instantaneous' high-resolution (1 Hz) emission data for the estimation of passenger car emissions during real-world driving. Extensive measurements of 20 EURO-I gasoline passenger cars have been used to predict emission factors for standard (i.e. legislative) as well as non-standard (i.e. real-world) driving patterns. It is shown that emission level predictions based upon chassis dynamometer tests over standard driving cycles significantly underestimate emission levels during real-world driving. The emission characteristics of modern passenger cars equipped with a three-way catalytic converter are a low, basic emission level on the one hand, and frequent emission 'peaks' on the other. For real-world driving, up to one-half of the entire emission can be emitted during these short-lasting peaks. Their frequency depends on various factors, including the level of 'dynamics' (speed variation) of the driving pattern. Because of this, the use of average speed as the only parameter to characterize emissions over a specific driving pattern is not sufficient. The instantaneous emissions approach uses an additional parameter representing engine load in order to resolve the differences between driving patterns with comparable average speeds but different levels of 'dynamics'. The paper includes an investigation of different statistical indicators and discusses methods to further improve the prediction capability of the instantaneous emission approach. The fundamental differences in emission-reduction strategies between different car manufacturers make the task of constructing a model valid for all catalyst passenger cars seemingly impossible, if the model is required to predict both fleet-averaged emission levels and emission factors for driving patterns of short duration for individual vehicles simultaneously.

  1. [Emission Factors of Vehicle Exhaust in Beijing].

    PubMed

    Fan, Shou-bin; Tian, Ling-di; Zhang, Dong-xu; Qu, Song

    2015-07-01

    Based on the investigation of basic data such as vehicle type composition, driving conditions, ambient temperature and oil quality, etc., emission factors of vehicle exhaust pollutants including carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC) and particulate matter(PM) were calculated using COPERT IV model. Emission factors of typical gasoline passenger cars and diesel trucks were measured using on-board measurement system on actual road. The measured and modeled emission factors were compared and the results showed that: the measured emission factors of CO, NOx and HC were 0. 96, 0. 64 and 4. 89 times of the modeled data for passenger cars conforming to the national IV emission standard. For the light, medium and heavy diesel trucks conforming to the national III emission standard, the measured data of CO emission factors were 1.61, 1. 07 and 1.76 times of the modeled data, respectively, the measured data of NOx emission factors were 1. 04, 1. 21 and 1. 18 times of the modeled data, and the measured data of HC emission factors were 3. 75, 1. 84 and 1. 47 times of the modeled data, while the model data of PM emission factors were 1. 31, 3. 42 and 6. 42 times of the measured data, respectively. PMID:26489301

  2. [Emission Factors of Vehicle Exhaust in Beijing].

    PubMed

    Fan, Shou-bin; Tian, Ling-di; Zhang, Dong-xu; Qu, Song

    2015-07-01

    Based on the investigation of basic data such as vehicle type composition, driving conditions, ambient temperature and oil quality, etc., emission factors of vehicle exhaust pollutants including carbon monoxide (CO), nitrogen oxides (NOx), hydrocarbons (HC) and particulate matter(PM) were calculated using COPERT IV model. Emission factors of typical gasoline passenger cars and diesel trucks were measured using on-board measurement system on actual road. The measured and modeled emission factors were compared and the results showed that: the measured emission factors of CO, NOx and HC were 0. 96, 0. 64 and 4. 89 times of the modeled data for passenger cars conforming to the national IV emission standard. For the light, medium and heavy diesel trucks conforming to the national III emission standard, the measured data of CO emission factors were 1.61, 1. 07 and 1.76 times of the modeled data, respectively, the measured data of NOx emission factors were 1. 04, 1. 21 and 1. 18 times of the modeled data, and the measured data of HC emission factors were 3. 75, 1. 84 and 1. 47 times of the modeled data, while the model data of PM emission factors were 1. 31, 3. 42 and 6. 42 times of the measured data, respectively.

  3. Road traffic emission factors for heavy metals

    NASA Astrophysics Data System (ADS)

    Johansson, Christer; Norman, Michael; Burman, Lars

    Quantifying the emissions and concentrations of heavy metals in urban air is a prerequisite for assessing their health effects. In this paper a combination of measurements and modelling is used to assess the contribution from road traffic emissions. Concentrations of particulate heavy metals in air were measured simultaneously during 1 year at a densely trafficked street and at an urban background site in Stockholm, Sweden. Annual mean concentrations of cadmium were 50 times lower than the EU directive and for nickel and arsenic concentrations were 10 and six times lower, respectively. More than a factor of two higher concentrations was in general observed at the street in comparison to roof levels indicating the strong influence from local road traffic emissions. The only compound with a significantly decreasing trend in the urban background was Pb with 9.1 ng m -3 in 1995/96 compared to 3.4 ng m -3 2003/04. This is likely due to decreased emissions from wear of brake linings and reduced emissions due to oil and coal combustion in central Europe. Total road traffic emission factors for heavy metals were estimated using parallel measurements of NOx concentrations and knowledge of NOx emission factors. In general, the emission factors for the street were higher than reported in road tunnel measurements. This could partly be due to different driving conditions, since especially for metals which are mainly emitted from brake wear, more stop and go driving in the street compared to in road tunnels is likely to increase emissions. Total emissions were compared with exhaust emissions, obtained from the COPERT model and brake wear emissions based on an earlier study in Stockholm. For Cu, Ni and Zn the sum of brake wear and exhaust emissions agreed very well with estimated total emission factors in this study. More than 90% of the road traffic emissions of Cu were due to brake wear. For Ni more than 80% is estimated to be due to exhaust emissions and for Zn around 40% of

  4. Particle emission factors during cooking activities

    NASA Astrophysics Data System (ADS)

    Buonanno, G.; Morawska, L.; Stabile, L.

    Exposure to particles emitted by cooking activities may be responsible for a variety of respiratory health effects. However, the relationship between these exposures and their subsequent effects on health cannot be evaluated without understanding the properties of the emitted aerosol or the main parameters that influence particle emissions during cooking. Whilst traffic-related emissions, stack emissions and concentrations of ultrafine particles (UFPs, diameter < 100 nm) in urban ambient air have been widely investigated for many years, indoor exposure to UFPs is a relatively new field and in order to evaluate indoor UFP emissions accurately, it is vital to improve scientific understanding of the main parameters that influence particle number, surface area and mass emissions. The main purpose of this study was to characterise the particle emissions produced during grilling and frying as a function of the food, source, cooking temperature and type of oil. Emission factors, along with particle number concentrations and size distributions were determined in the size range 0.006-20 μm using a Scanning Mobility Particle Sizer (SMPS) and an Aerodynamic Particle Sizer (APS). An infrared camera was used to measure the temperature field. Overall, increased emission factors were observed to be a function of increased cooking temperatures. Cooking fatty foods also produced higher particle emission factors than vegetables, mainly in terms of mass concentration, and particle emission factors also varied significantly according to the type of oil used.

  5. TEMPORAL VARIABILITY IN BASAL ISOPRENE EMISSION FACTOR

    EPA Science Inventory

    Seasonal variability in basal isoprene emission factor (micrograms C /g hr or nmol/ m2 sec, leaf temperature at 30 degrees C and photosynthetically active radiation (PAR) at 1000 micromol/ m2 sec) was studied during the 1998 growing season at Duke Forest in the North Carolina Pie...

  6. DEVELOPMENT AND SELECTION OF AMMONIA EMISSION FACTORS FOR THE 1985 NAPAP EMISSIONS INVENTORY

    EPA Science Inventory

    The report, prepared for the National Acid Precipitation Assessment Program (NAPAP), identifies the most appropriate ammonia (NH3) emission factors available for inclusion in the 1985 NAPAP Emissions Inventory. H3 emission factors developed for several new NAPAP source categories...

  7. THE 1985 NAPAP EMISSIONS INVENTORY: DEVELOPMENT OF TEMPORAL ALLOCATION FACTORS

    EPA Science Inventory

    The report documents the development and processing of temporal allocation factors for the 1985 National Acid Precipitation Assessment Program (NAPAP) emissions inventory (Version 2). The NAPAP emissions inventory represents the most comprehensive emissions data base available fo...

  8. Factors controlling dimethylsulfide emission from salt marshes

    NASA Technical Reports Server (NTRS)

    Dacey, John W. H.; Wakeham, S. G.; Howes, B. L.

    1985-01-01

    The factors that control the emission of methylated gases from salt marshes are being studied. Research focusses on dimethylsulfide (DMS) formation and the mechanism of DMS and CH4 emission to the atmosphere. The approach is to consider the plants as valves regulating the emission of methylated gases to the atmosphere with the goal of developing appropriate methods for emission measurement. In the case of CH4, the sediment is the source and transport to the atmosphere occurs primarily through the internal gas spaces in the plants. The source of DMS appears to be dimethyl sulfoniopropionate (DMSP) which may play a role in osmoregulation in plant tissues. Concentrations of DMSP in leaves are typically several-fold higher than in roots and rhizomes. Even so, the large below ground biomass of this plant means that 2/3 of the DMSP in the ecosystem is below ground on the aerial basis. Upon introduction to sediment water, DMSP rapidly decomposes to DMS and acrylic acid. The solubility of a gas (its equilibrium vapor pressure) is a fundamental aspect of gas exchange kinetics. The first comprehensive study was conducted of DMS solubility in freshwater and seawater. Data suggest that the Setchenow relation holds for H at intermediate salinities collected. These data support the concept that the concentration of DMS in the atmosphere is far from equilibrium with seawater.

  9. Emission factors for smouldering peat megafires

    NASA Astrophysics Data System (ADS)

    Hadden, Rory; Santamaria, Simon; Pironi, Paolo; Rein, Guillermo

    2016-04-01

    Smouldering wildfires occur in large deposits of peat across the globe in boreal and temperate regions. These fires are the most persistent fires on earth and consume large quantities of biomass which can take centuries or longer to regenerate. Recently large peat fires in Indonesia have caused significant health issues across a large geographic area in south east Asia. A similar event that occurred in 1997 was estimated to have released up to 13.7Gt of carbon to the atmosphere. Globally, the carbon stored in peatlands is greater than that stored in vegetation and is similar to that stored in the atmosphere. One of the major threats to these ecosystems is smouldering megafires which can be ignited easily in peat with the resulting fire persisting for extended periods of time (often many weeks or months). Given the potential impact on global carbon balances, it is essential to have accurate estimates of carbon emitted from these fires. Is is established that the emissions from any combustion process are strongly dependent on the combustion conditions these include the temperature (energy balance), availability of oxygen and the fuel composition. Because smouldering is a persistent form of combustion, it can occur over a wide range of conditions. This necessitates an understanding of emission factors linked to the burning dynamics. To allow for controlled, repeatable burning conditions across this range of conditions, a series of laboratory scale experiments were undertaken to identify the carbon dioxide, carbon monoxide and methane flux from samples of smouldering sphagnum moss peat. This peat is used as it has been extensively studied experimentally and numerically. By using repeatable experimental conditions delivered by the FM Global Fire Propagation Apparatus, the flux of CO, CO2 and methane can be linked to the smouldering fire dynamics. Smouldering in shallow fronts is represented by burning in ambient oxygen concentration while deep fronts are simulated using

  10. Implications of diesel emissions control failures to emission factors and road transport NOx evolution

    NASA Astrophysics Data System (ADS)

    Ntziachristos, Leonidas; Papadimitriou, Giannis; Ligterink, Norbert; Hausberger, Stefan

    2016-09-01

    Diesel NOx emissions have been at the forefront of research and regulation scrutiny as a result of failures of late vehicle technologies to deliver on-road emissions reductions. The current study aims at identifying the actual emissions levels of late light duty vehicle technologies, including Euro 5 and Euro 6 ones. Mean NOx emission factor levels used in the most popular EU vehicle emission models (COPERT, HBEFA and VERSIT+) are compared with latest emission information collected in the laboratory over real-world driving cycles and on the road using portable emissions measurement systems (PEMS). The comparison shows that Euro 5 passenger car (PC) emission factors well reflect on road levels and that recently revealed emissions control failures do not call for any significant corrections. However Euro 5 light commercial vehicles (LCVs) and Euro 6 PCs in the 2014-2016 period exhibit on road emission levels twice as high as used in current models. Moreover, measured levels vary a lot for Euro 6 vehicles. Scenarios for future evolution of Euro 6 emission factors, reflecting different degree of effectiveness of emissions control regulations, show that total NOx emissions from diesel Euro 6 PC and LCV may correspond from 49% up to 83% of total road transport emissions in 2050. Unless upcoming and long term regulations make sure that light duty diesel NOx emissions are effectively addressed, this will have significant implications in meeting future air quality and national emissions ceilings targets.

  11. WOODSTOVE EMISSION MEASUREMENT METHODS COMPARISON AND EMISSION FACTORS UPDATE

    EPA Science Inventory

    This paper compares various field and laboratory woodstove emission measurement methods. n 1988, the U.S. EPA promulgated performance standards for residential wood heaters (woodstoves). ver the past several years, a number of field studies have been undertaken to determine the a...

  12. THE 1985 NAPAP EMISSIONS INVENTORY: DEVELOPMENT OF SPECIES ALLOCATION FACTORS

    EPA Science Inventory

    The report describes the methodologies and data bases used to develop species allocation factors and data processing software used to develop the 1985 National Acid Precipitation Assessment Program (NAPAP) Modelers' Emissions Inventory (Version 2). Species allocation factors were...

  13. [Greenhouse gas emission from reservoir and its influence factors].

    PubMed

    Zhao, Xiao-jie; Zhao, Tong-qian; Zheng, Hua; Duan, Xiao-nan; Chen, Fa-lin; Ouyang, Zhi-yun; Wang, Xiao-ke

    2008-08-01

    Reservoirs are significant sources of emissions of the greenhouse gases. Discussing greenhouse gas emission from the reservoirs and its influence factors are propitious to evaluate emission of the greenhouse gas accurately, reduce gas emission under hydraulic engineering and hydropower development. This paper expatiates the mechanism of the greenhouse gas production, sums three approaches of the greenhouse gas emission, which are emissions from nature emission of the reservoirs, turbines and spillways and downstream of the dam, respectively. Effects of greenhouse gas emission were discussed from character of the reservoirs, climate, pH of the water, vegetation growing in the reservoirs and so on. Finally, it has analyzed the heterogeneity of the greenhouse gas emission as well as the root of the uncertainty and carried on the forecast with emphasis to the next research.

  14. Compilation of air pollutant emission factors, supplement 12

    SciTech Connect

    Not Available

    1981-04-01

    Revised or updated data are presented for dry cleaning: surface coating, storage of organic liquids, solvent degreasing, graphic arts, consumer/commercial solvent use, sulfuric acid, beer making, ammonium sulfate, primary aluminum, secondary aluminum, gray iron foundries, steel foundries, secondary zinc, asphaltic concrete, asphalt roofing, NEDS source classification codes and emission factor listing, and table of lead emission factors.

  15. Estimation of vehicular emissions using dynamic emission factors: A case study of Delhi, India

    NASA Astrophysics Data System (ADS)

    Mishra, Dhirendra; Goyal, P.

    2014-12-01

    The estimation of vehicular emissions depends mainly on the values of emission factors, which are used for the development of a comprehensive emission inventory of vehicles. In this study the variations of emission factors as well as the emission rates have been studied in Delhi. The implementation of compressed natural gas (CNG), in the diesel and petrol, public vehicles in the year 2001 has changed the complete air quality scenario of Delhi. The dynamic emission factors of criteria pollutants viz. carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM10) for all types of vehicles have been developed after, which are based on the several factors such as regulated emission limits, number of vehicle deterioration, vehicle increment, vehicle age etc. These emission factors are found to be decreased continuously throughout the study years 2003-2012. The International Vehicle Emissions (IVE) model is used to estimate the emissions of criteria pollutants by utilizing a dataset available from field observations at different traffic intersections in Delhi. Thus the vehicular emissions, based on dynamic emission factors have been estimated for the years 2003-2012, which are found to be comparable with the monitored concentrations at different locations in Delhi. It is noticed that the total emissions of CO, NOx, and PM10 are increased by 45.63%, 68.88% and 17.92%, respectively up to the year 2012 and the emissions of NOx and PM10 are grown continuously with an annual average growth rate of 5.4% and 1.7% respectively.

  16. Combustion sources of particles: 2. Emission factors and measurement methods.

    PubMed

    Zhang, Junfeng Jim; Morawska, Lidia

    2002-12-01

    Emissions from the combustion of biomass and fossil fuels are a significant source of particulate matter (PM) in ambient outdoor and/or indoor air. It is important to quantify PM emissions from combustion sources for regulatory and control purposes in relation to air quality. In this paper, we review emission factors for several types of important combustion sources: road transport, industrial facilities, small household combustion devices, environmental tobacco smoke, and vegetation burning. We also review current methods for measuring particle physical characteristics (mass and number concentrations) and principles of methodologies for measuring emission factors. The emission factors can be measured on a fuel-mass basis and/or a task basis. Fuel-mass based emission factors (e.g., g/kg of fuel) can be readily used for the development of emission inventories when the amount of fuels consumed are known. Task-based emission factors (g/mile driven, g/MJ generated) are more appropriate when used to conduct comparisons of air pollution potentials of different combustion devices. Finally, we discuss major shortcomings and limitations of current methods for measuring particle emissions and present recommendations for development of future measurement techniques. PMID:12492165

  17. Factors affecting methane emission from rice fields

    NASA Astrophysics Data System (ADS)

    Neue, H. U.; Wassmann, R.; Lantin, R. S.; Alberto, Ma C. R.; Aduna, J. B.; Javellana, A. M.

    Emission of CH 4 from ricefields is the result of anoxic bacterial methane production. Global estimates of annual CH 4 emission from ricefields is 100 Tg. CH 4 emission data from limited sites are tentative. It is essential that uncertainty in individual sources is reduced in order to develop feasible and effective mitigation options which do not negate gains in rice production and productivity. Field studies at the International Rice Research Institute show that soil and added organic matter are the sources for initial methane production. Addition of rice straw enhances methane production. Roots and root exudates of wetland rice plants appear to be the major carbon sources at ripening stage. The production and transport of CH 4 to the atmosphere depend on properties of the rice plant. Under the same spacing and fertilization, the traditional variety Dular emitted more CH 4 per day than did the new plant type IR65597. Upon flooding for land preparation anaerobic conditions result in significant amount of methane being formed. Drying the field at midtillering significantly reduced total CH 4 emissions. Large amounts of entrapped CH 4 escape to the atmosphere when floodwater recedes upon drying at harvest. Cultural practices may account for 20% of the overall seasonal CH 4 emissions.

  18. Through-tunnel estimates of vehicle fleet emission factors

    NASA Astrophysics Data System (ADS)

    Brimblecombe, Peter; Townsend, Thomas; Lau, Chui Fong; Rakowska, Agata; Chan, Tat Leung; Močnik, Griša; Ning, Zhi

    2015-12-01

    On-road measurements of traffic-related gas and particle pollutant concentrations in three tunnels in Hong Kong and high resolution pollutant concentration profiles obtained while driving through the tunnels were used to derive the individual pollutant gradients using parametric and non-parametric (Sen-Thiel) slopes and compared with the commonly used entrance-exit two points calculation. The fuel based emission factors of measured pollutants for individual tunnels at different times of day were derived from gradients using a new method based on fuel carbon balance principle. Combined with the tunnel traffic volume and composition, the average tunnel emission factors were analyzed by linear regression to derive the diesel fleet emission factors. Average nitrogen oxides (NOx) and black carbon (BC) emission factor for diesel fleets are 29.3 ± 11.0 gNO2 kg-1 and 1.28 ± 0.76 g kg-1 of fuel, respectively. The results from the study were compared with the emission data from vehicle chasing approaches and the literature, showing reasonable agreement. Practical limitations and future direction for improvement of our method were also discussed. The method presented in this study provides a convenient drive-through approach for fast determination of tunnel and individual vehicle fleet emission factors. It can be used as an effective and fast approach to validate the emission inventory and to evaluate the effectiveness of policy intervention on the traffic emissions.

  19. Improving emissions factors for estimating urban natural gas leakage

    NASA Astrophysics Data System (ADS)

    Phillips, Nathan

    2013-04-01

    Emissions factors for pipeline natural gas leaks are in need of refinement. In addition to limitations from the small sample sizes of leaks that were initially used to develop emissions factors, a further limitation to emissions factors is lack of knowledge of characteristic statistical distributions of pipeline leak rates. For example, leaks were implicitly assumed to be normally distributed so that an average leak rate was used for pipelines of a given construction. Our natural gas leak data from Boston, USA, in which we found over 3,000 natural gas leaks, indicates that leaks rates are highly skewed, with relatively few leaks likely contributing disproportionately to the total. The long-tailed distribution of gas leak rates is mirrored by a similarly skewed distribution of surface methane concentrations in air. These data suggest that emissions factors should be based on correctly specified statistical distributions, and that fixing relatively few large leaks first may provide the most environmental benefit per cost.

  20. Case study of polychlorinated naphthalene emissions and factors influencing emission variations in secondary aluminum production.

    PubMed

    Jiang, Xiaoxu; Liu, Guorui; Wang, Mei; Liu, Wenbin; Tang, Chen; Li, Li; Zheng, Minghui

    2015-04-01

    Secondary aluminum production has been recognized as an important source of polychlorinated naphthalenes (PCNs). Large variations in PCN emissions as the smelting process proceeds have not been determined. In this study, solid and gaseous discharges, including fly ash, slag, and stack gas samples collected from four secondary smelting plants during different smelting stages were analyzed for PCNs. The average emission factor of ∑(1-8)PCNs to air was calculated to be 17.4 mg t(-1), with a range of 4.3-29.5 mg t(-1). The average emission factors of ∑(1-8)PCNs from fly ash and slag were 55.5 ng t(-1) and 0.13 ng t(-1), respectively. The derived emission factors may enable a more accurate estimation of annual emissions and a more comprehensive knowledge of the distribution of PCNs emitted from secondary aluminum production. The emission levels and characteristics of PCNs during different smelting stages were compared. Possible factors, including the organic impurities from aluminum scrap, fuel, and chloride additives, which could contribute to variations in PCN emissions and characteristics were discussed. These results may provide useful information for developing better control strategies for reducing PCN emissions in secondary aluminum production.

  1. Effect of Environmental Factors on Sulfur Gas Emissions from Drywall

    SciTech Connect

    Maddalena, Randy

    2011-08-20

    Problem drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. The U.S. Consumer Product Safety Commission's (CPSC) investigation of problem drywall incorporates three parallel tracks: (1) evaluating the relationship between the drywall and reported health symptoms; (2) evaluating the relationship between the drywall and electrical and fire safety issues in affected homes; and (3) tracing the origin and the distribution of the drywall. To assess the potential impact on human health and to support testing for electrical and fire safety, the CPSC has initiated a series of laboratory tests that provide elemental characterization of drywall, characterization of chemical emissions, and in-home air sampling. The chemical emission testing was conducted at Lawrence Berkeley National Laboratory (LBNL). The LBNL study consisted of two phases. In Phase 1 of this study, LBNL tested thirty drywall samples provided by CPSC and reported standard emission factors for volatile organic compounds (VOCs), aldehydes, reactive sulfur gases (RSGs) and volatile sulfur compounds (VSCs). The standard emission factors were determined using small (10.75 liter) dynamic test chambers housed in a constant temperature environmental chamber. The tests were all run at 25 C, 50% relative humidity (RH) and with an area-specific ventilation rate of {approx}1.5 cubic meters per square meter of emitting surface per hour [m{sup 3}/m{sup 2}/h]. The thirty samples that were tested in Phase 1 included seventeen that were manufactured in China in 2005, 2006 and 2009, and thirteen that were manufactured in North America in 2009. The measured emission factors for VOCs and aldehydes were generally low and did not differ significantly between the Chinese and North American drywall. Eight of the samples tested had elevated emissions of volatile sulfur-containing compounds with total RSG emission factors between 32 and 258 micrograms per square meter

  2. Emissions from laboratory combustion of wildland fuels: emission factors and source profiles.

    PubMed

    Chen, L W Antony; Moosmüller, Hans; Arnott, W Patrick; Chow, Judith C; Watson, John G; Susott, Ronald A; Babbitt, Ronald E; Wold, Cyle E; Lincoln, Emily N; Hao, Wei Min

    2007-06-15

    Combustion of wildland fuels represents a major source of particulate matter (PM) and light-absorbing elemental carbon (EC) on a national and global scale, but the emission factors and source profiles have not been well characterized with respect to different fuels and combustion phases. These uncertainties limit the accuracy of current emission inventories, smoke forecasts, and source apportionments. This study investigates the evolution of gaseous and particulate emission and combustion efficiency by burning wildland fuels in a laboratory combustion facility. Emission factors for carbon dioxide (CO2), carbon monoxide (CO), total hydrocarbon (THC), nitrogen oxides (NO(x)), PM, light extinction and absorption cross sections, and spectral scattering cross sections specific to flaming and smoldering phases are reported. Emission factors are generally reproducible within +/- 20% during the flaming phase, which, despite its short duration, dominates the carbon emission (mostly in the form of CO2) and the production of light absorption and EC. Higher and more variable emission factors for CO, THC, and PM are found during the smoldering phase, especially for fuels containing substantial moisture. Organic carbon (OC) and EC mass account for a majority (i.e., > 60%) of PM mass; other important elements include potassium, chlorine, and sulfur. Thermal analysis separates the EC into subfractions based on analysis temperature demonstrating that high-temperature EC (EC2; at 700 degrees C) varies from 1% to 70% of PM among biomass burns, compared to 75% in kerosene soot. Despite this, the conversion factor between EC and light absorption emissions is rather consistent across fuels and burns, ranging from 7.8 to 9.6 m2/g EC. Findings from this study should be considered in the development of PM and EC emission inventories for visibility and radiative forcing assessments.

  3. Environmental factors controlling methane emissions from peatlands in northern Minnesota

    NASA Technical Reports Server (NTRS)

    Dise, Nancy B.; Gorham, Eville; Verry, Elon S.

    1993-01-01

    The environmental factors affecting the emission of methane from peatlands were investigated by correlating CH4 emission data for two years, obtained from five different peatland ecosystems in northern Minnesota, with peat temperature, water table position, and degree of peat humification. The relationship obtained between the CH4 flux and these factors was compared to results from a field manipulation experiment in which the water table was artificially raised in three experimental plots within the driest peatland. It was found that peat temperature, water table position, and degree of peat humification explained 91 percent of the variance in log CH4 flux, successfully predicted annual CH4 emission from individual wetlands, and predicted the change in flux due to the water table manipulation. Raising the water table in the bog corrals by an average of 6 cm in autumn 1989 and 10 cm in summer 1990 increased CH4 emission by 2.5 and 2.2 times, respectively.

  4. Environmental factors controlling methane emissions from peatlands in northern Minnesota

    NASA Astrophysics Data System (ADS)

    Dise, Nancy B.; Gorham, Eville; Verry, Elon S.

    1993-06-01

    The environmental factors affecting the emission of methane from peatlands were investigated by correlating CH4 emission data for two years, obtained from five different peatland ecosystems in northern Minnesota, with peat temperature, water table position, and degree of peat humification. The relationship obtained between the CH4 flux and these factors was compared to results from a field manipulation experiment in which the water table was artificially raised in three experimental plots within the driest peatland. It was found that peat temperature, water table position, and degree of peat humification explained 91 percent of the variance in log CH4 flux, successfully predicted annual CH4 emission from individual wetlands, and predicted the change in flux due to the water table manipulation. Raising the water table in the bog corrals by an average of 6 cm in autumn 1989 and 10 cm in summer 1990 increased CH4 emission by 2.5 and 2.2 times, respectively.

  5. Emission factors from road dust resuspension in a Mediterranean freeway

    NASA Astrophysics Data System (ADS)

    Amato, F.; Karanasiou, A.; Moreno, T.; Alastuey, A.; Orza, J. A. G.; Lumbreras, J.; Borge, R.; Boldo, E.; Linares, C.; Querol, X.

    2012-12-01

    Particulate matter emissions from paved roads are currently one of the main challenges for a sustainable transport in Europe. Emissions are scarcely estimated due to the lack of knowledge about the resuspension process severely hampering a reliable simulation of PM and heavy metals concentrations in large cities and evaluation of population exposure. In this study the Emission Factors from road dust resuspension on a Mediterranean freeway were estimated per single vehicle category and PM component (OC, EC, mineral dust and metals) by means of the deployment of vertical profiles of passive samplers and terminal concentration estimate. The estimated PM10 emission factors varied from 12 to 47 mg VKT-1 (VKT: Vehicle Kilometer Traveled) with an average value of 22.7 ± 14.2 mg VKT-1. Emission Factors for heavy and light duty vehicles, passenger cars and motorbikes were estimated, based on average fleet composition and EPA ratios, in 187-733 mg VKT-1, 33-131 VKT-1, 9.4-36.9 VKT-1 and 0.8-3.3 VKT-1, respectively. These range of values are lower than previous estimates in Mediterranean urban roads, probably due to the lower dust reservoir on freeways. PM emitted material was dominated by mineral dust (9-10 mg VKT-1), but also OC and EC were found to be major components and approximately 14-25% and 2-9% of average PM exhaust emissions from diesel passenger cars on highways respectively.

  6. Evaluation of an Odour Emission Factor (OEF) to estimate odour emissions from landfill surfaces

    NASA Astrophysics Data System (ADS)

    Lucernoni, Federico; Tapparo, Federica; Capelli, Laura; Sironi, Selena

    2016-11-01

    Emission factors are fundamental tools for air quality management. Odour Emission Factors (OEFs) can be developed in analogy with the emission factors defined for other chemical compounds, which relate the quantity of a pollutant released to the atmosphere to a given associated activity. Landfills typically represent a common source of odour complaint; for this reason, the development of specific OEFs allowing the estimation of odour emissions from this kind of source would be of great interest both for the landfill design and management. This study proposes an up-to-date methodology for the development of an OEF for the estimation of odour emissions from landfills, thereby focusing on the odour emissions related to the emissions of landfill gas (LFG) from the exhausted landfill surface. The proposed approach is an "indirect" approach based on the quantification of the LFG emissions from methane concentration measurements carried out on an Italian landfill. The Odour Emission Rate (OER) is then obtained by multiplying the emitted gas flow rate by the LFG odour concentration. The odour concentration of the LFG emitted through the landfill surface was estimated by means of an ad hoc correlation investigated between methane concentration and odour concentration. The OEF for the estimation of odour emissions from landfill surfaces was computed, considering the landfill surface as the activity index, as the product between the mean specific LFG flux emitted through the surface resulting from the experimental campaigns, equal to 0.39 l/m2/h, and its odour concentration, which was estimated to be equal to 105‧000 eq. ouE/m3, thus giving an OEF of 0.011 ouE/m2/s. This value, which is considerably lower than those published in previous works, should be considered as an improved estimation based on the most recent developments of the research in the field of odour sampling on surface sources.

  7. Factors affecting heavy-duty diesel vehicle emissions.

    PubMed

    Clark, Nigel N; Kern, Justin M; Atkinson, Christopher M; Nine, Ralph D

    2002-01-01

    Societal and governmental pressures to reduce diesel exhaust emissions are reflected in the existing and projected future heavy-duty certification standards of these emissions. Various factors affect the amount of emissions produced by a heterogeneous charge diesel engine in any given situation, but these are poorly quantified in the existing literature. The parameters that most heavily affect the emissions from compression ignition engine-powered vehicles include vehicle class and weight, driving cycle, vehicle vocation, fuel type, engine exhaust aftertreatment, vehicle age, and the terrain traveled. In addition, engine control effects (such as injection timing strategies) on measured emissions can be significant. Knowing the effect of each aspect of engine and vehicle operation on the emissions from diesel engines is useful in determining methods for reducing these emissions and in assessing the need for improvement in inventory models. The effects of each of these aspects have been quantified in this paper to provide an estimate of the impact each one has on the emissions of diesel engines.

  8. Measurements of air pollution emission factors for marine transportation

    NASA Astrophysics Data System (ADS)

    Alföldy, B.; Balzani Lööv, J.; Lagler, F.; Mellqvist, J.; Berg, N.; Beecken, J.; Weststrate, H.; Duyzer, J.; Bencs, L.; Horemans, B.; Cavalli, F.; Putaud, J.-P.; Janssens-Maenhout, G.; Pintér Csordás, A.; Van Grieken, R.; Borowiak, A.; Hjorth, J.

    2012-12-01

    The chemical composition of the plumes of seagoing ships was investigated during a two weeks long measurement campaign in the port of Rotterdam, Hoek van Holland, The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg-1 fuel) was provided. The concerned main atmospheric components were SO2, NO2, NOx and the aerosol particle number. In addition, the elemental and water-soluble ionic composition of the emitted particulate matter was determined. Emission factors were expressed as a function of ship type, power and crankshaft rotational speed. The average SO2 emission factor was found to be roughly half of what is allowed in sulphur emission control areas (16 vs. 30 g kg-1 fuel), and exceedances of this limit were rarely registered. A significant linear relationship was observed between the SO2 and particle number emission factor. The intercept of the regression line, 0.5 × 1016 (kg fuel)-1, gives the average number of particles formed during the burning of 1 kg zero sulphur content fuel, while the slope, 2 × 1018, provides the average number of particles formed with 1 kg sulphur burnt with the fuel. Water-soluble ionic composition analysis of the aerosol samples from the plumes showed that ~144 g of particulate sulphate was emitted from 1 kg sulphur burnt with the fuel. The mass median diameter of sulphate particles estimated from the measurements was ~42 nm.

  9. Emission factors and exposures from ground-level pyrotechnics

    NASA Astrophysics Data System (ADS)

    Croteau, Gerry; Dills, Russell; Beaudreau, Marc; Davis, Mac

    Potential exposures from ground-level pyrotechnics were assessed by air monitoring and developing emission factors. Total particulate matter, copper and SO 2 exposures exceeded occupational health guidelines at two outdoor performances using consumer pyrotechnics. Al, Ba, B, Bi, Mg, Sr, Zn, and aldehyde levels were elevated, but did not pose a health hazard based on occupational standards. Emission factors for total particulate matter, metals, inorganic ions, aldehydes, and polyaromatic hydrocarbons (PAHs) were determined for seven ground-supported pyrotechnics through air sampling in an airtight room after combustion. Particle generation ranged from 5 to 13% of the combusted mass. Emission factors (g Kg -1) for metals common to pyrotechnics were also high: K, 23-45; Mg, 1-7; Cu, 0.05-7; and Ba, 0.03-6. Pb emission rates of 1.6 and 2.7% of the combusted mass for two devices were noteworthy. A high correlation ( r2 ≥ 0.89) between metal concentrations in pyrotechnic compositions and emission factors were noted for Pb, Cr, Mg, Sb, and Bi, whereas low correlations ( r2 ≤ 0.1) were observed for Ba, Sr, Fe, and Zn. This may be due to the inherent heterogeneity of multi-effect pyrotechnics. The generation of inorganic nitrogen in both the particulate (NO 2-, NO 3-) and gaseous (NO, NO 2) forms varied widely (<0.1-1000 mg Kg -1). Aldehyde emission factors varied by two orders of magnitude even though the carbon source was carbohydrates and charcoal for all devices: formaldehyde (<7.0-82 mg Kg -1), acetaldehyde (43-210 mg Kg -1), and acrolein (1.9-12 mg Kg -1). Formation of lower molecular weight PAHs such as naphthalene and acenaphthylene were favored, with their emission factors being comparable to that from the combustion of household refuse and agricultural debris. Ba, Sr, Cu, and Pb had emission factors that could produce exposures exceeding occupational exposure guidelines. Sb and unalloyed Mg, which are banned from consumer fireworks in the US, were present in

  10. Update on the development of cotton gin PM10 emission factors for EPA's AP-42

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cotton ginning industry-supported project was initiated in 2008 to update the U.S. Environmental Protection Agency’s (EPA) Compilation of Air Pollution Emission Factors (AP-42) to include PM10 emission factors. This study develops emission factors from the PM10 emission factor data collected from ...

  11. Ranking factors affecting emissions of GHG from incubated agricultural soils

    PubMed Central

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-01-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO3−) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L16 design, comprising 16 experimental units. Within this L16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO3− addition were the main factors affecting N2O fluxes, whilst glucose, NO3− and soil temperature were the main factors affecting CO2 and CH4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time. PMID:25177207

  12. Ranking factors affecting emissions of GHG from incubated agricultural soils.

    PubMed

    García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

    2014-07-01

    Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO3 (-)) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L16 design, comprising 16 experimental units. Within this L16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO3 (-) addition were the main factors affecting N2O fluxes, whilst glucose, NO3 (-) and soil temperature were the main factors affecting CO2 and CH4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time. PMID:25177207

  13. Aromatic compound emissions from municipal solid waste landfill: Emission factors and their impact on air pollution

    NASA Astrophysics Data System (ADS)

    Liu, Yanjun; Lu, Wenjing; Guo, Hanwen; Ming, Zhongyuan; Wang, Chi; Xu, Sai; Liu, Yanting; Wang, Hongtao

    2016-08-01

    Aromatic compounds (ACs) are major components of volatile organic compounds emitted from municipal solid waste (MSW) landfills. The ACs emissions from the working face of a landfill in Beijing were studied from 2014 to 2015 using a modified wind tunnel system. Emission factors (EFs) of fugitive ACs emissions from the working face of the landfill were proposed according to statistical analyses to cope with their uncertainty. And their impacts on air quality were assessed for the first time. Toluene was the dominant AC with an average emission rate of 38.8 ± 43.0 μg m-2 s-1 (at a sweeping velocity of 0.26 m s-1). An increasing trend in AC emission rates was observed from 12:00 to 18:00 and then peaked at 21:00 (314.3 μg m-2 s-1). The probability density functions (PDFs) of AC emission rates could be classified into three distributions: Gaussian, log-normal, and logistic. EFs of ACs from the working face of the landfill were proposed according to the 95th percentile cumulative emission rates and the wind effects on ACs emissions. The annual ozone formation and secondary organic aerosol formation potential caused by AC emissions from landfills in Beijing were estimated to be 8.86 × 105 kg year-1 and 3.46 × 104 kg year-1, respectively. Toluene, m + p-xylene, and 1,3,5-trimethylbenzene were the most significant contributors to air pollution. Although ACs pollutions from landfills accounts for less percentage (∼0.1%) compared with other anthropogenic sources, their fugitive emissions which cannot be controlled efficiently deserve more attention and further investigation.

  14. Emission factors from small scale appliances burning wood and pellets

    NASA Astrophysics Data System (ADS)

    Ozgen, Senem; Caserini, Stefano; Galante, Silvia; Giugliano, Michele; Angelino, Elisabetta; Marongiu, Alessandro; Hugony, Francesca; Migliavacca, Gabriele; Morreale, Carmen

    2014-09-01

    Four manually fed (6-11 kW) firewood burning and two automatic wood pellets (8.8-25 kW) residential heating appliances were tested under real-world operating conditions in order to determine emission factors (EFs) of macropollutants, i.e., carbon monoxide (CO), nitrogen oxides (NOx), non-methane hydrocarbons (NMHC), particulate matter (PM) and trace pollutants such as polycyclic aromatic hydrocarbons (PAH) and dioxins. The results were examined for the influence of different factors (i.e., type of wood, appliance and combustion cycle). The experimental EFs were also compared with the values proposed by the European emission inventory guidebook used in the local inventory in order to evaluate their representativeness of real world emissions. The composite macropollutant EFs for manually fed appliances were: for CO 5858 g GJ-1, for NOx 122 g GJ-1, NMHC 542 g GJ-1, PM 254 g GJ-1, whereas emissions were much lower for automatic pellets appliances: CO 219 g GJ-1, for NOx 66 g GJ-1, NMHC 5 g GJ-1, PM 85 g GJ-1. The highest emissions were generally observed for the open fireplace, however traditional and advanced stoves have the highest overall CO EFs. Especially for the advanced stove real-world emissions are far worse than those measured under cycles used for type testing of residential solid fuel appliances. No great difference is observed for different firewood types in batch working appliances, diversely the quality of the pellets is observed to influence directly the emission performance of the automatic appliances. Benzo(b)fluoranthene is the PAH with the highest contribution (110 mg GJ-1 for manual appliances and 2 mg GJ-1 for automatic devices) followed by benzo(a)pyrene (77 mg GJ-1 for manual appliances and 0.8 mg GJ-1 for automatic devices).

  15. SENSITIVITY ANALYSIS AND EVALUATION OF MICROFACPM: A MICROSCALE MOTOR VEHICLE EMISSION FACTOR MODEL FOR PARTICULATE MATTER EMISSIONS

    EPA Science Inventory

    A microscale emission factor model (MicroFacPM) for predicting real-time site-specific motor vehicle particulate matter emissions was presented in the companion paper entitled "Development of a Microscale Emission Factor Model for Particulate Matter (MicroFacPM) for Predicting Re...

  16. Development of database of real-world diesel vehicle emission factors for China.

    PubMed

    Shen, Xianbao; Yao, Zhiliang; Zhang, Qiang; Wagner, David Vance; Huo, Hong; Zhang, Yingzhi; Zheng, Bo; He, Kebin

    2015-05-01

    A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models. PMID:25968276

  17. Development of database of real-world diesel vehicle emission factors for China.

    PubMed

    Shen, Xianbao; Yao, Zhiliang; Zhang, Qiang; Wagner, David Vance; Huo, Hong; Zhang, Yingzhi; Zheng, Bo; He, Kebin

    2015-05-01

    A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China, NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-based models will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models.

  18. Review of ammonia emission factors for United States animal agriculture

    NASA Astrophysics Data System (ADS)

    Faulkner, W. B.; Shaw, B. W.

    Ammonia emissions from agricultural industries are a significant source of atmospheric reactive nitrogen, which can lead to negative environmental consequences such as ecosystem change and formation of fine particulate. While a number of emission factors (EFs) have been proposed for developing ammonia emissions inventories for the US, most are based on European research with little discussion of their applicability to US production systems. Recently developed ammonia EFs from literature for animal feeding operations (AFOs), including production facilities for beef and dairy cattle, swine, and poultry, are presented. Tentative EFs for US animal agriculture are suggested until further research can be conducted. Currently, there is a dearth of EFs developed specifically for agricultural production practices in the US.

  19. Factors affecting NO sub x emissions in heavy oil combustion

    SciTech Connect

    Kerho, S.E.; Giovanni, D.V. )

    1991-06-01

    For a given boiler geometry and burner design, the major factors affecting NO{sub x} emissions are excess O{sub 2} level, fuel nitrogen content, and atomization quality. In this project, the available technical literature was reviewed to develop correlations to predict the effects of excess O{sub 2} and fuel nitrogen concentration on NO{sub x} emissions. NO{sub x}/O{sub 2} and NO{sub x}/fuel-nitrogen correlations are provided for tangentially fired units and wall-fired units with single-register, low-excess-air, and low-NO{sub x} burners. Although promising trends were observed, available data were not sufficient to allow the development of similar correlations to predict the effect of changes in atomization quality on NO{sub x} emissions. As a result, further combustion tests are planned to study the effects of atomization quality. 14 refs., 28 figs., 7 tabs.

  20. Pre-Harvest Sugarcane Burning: Determination of emission factors through laboratory measurements and quantification of emissions

    NASA Astrophysics Data System (ADS)

    de Azeredo Franca, D.; Maria Longo, K.; Gomes Soares Neto, T.; Carlos dos Santos, J.; Rudorf, B. F.; Alves de Aguiar, D.; Freitas, S.; Vieira Cortez, E.; Stockler S. Lima, R.; S. Gacita, M.; Anselmo, E.; A. Carvalho, J., Jr.

    2011-12-01

    Sugarcane is a relevant crop to Brazilian economy and roughly 50% of its production is used to produce ethanol. São Paulo state is the largest producer of sugarcane in Brazil being responsible for almost 60% of its production in a cultivated area of 4.5 Mha in 2010. Sugarcane harvest practice can be performed either with green harvest or with pre-harvest burning. A "Green Ethanol" Protocol is underway to eliminate the pre-harvest burning practice by 2014 in most of the sugarcane cultivated land in São Paulo state. During the last five years close to 2 Mha were annually harvested with the pre-harvest burning practice. This practice emits particulate material, greenhouse gases, and tropospheric ozone precursors to the atmosphere. Even with policies to eliminate the burning practice in the near future there is still a significant environmental damage due to the pre-harvest burning practice of sugarcane. Thus the generation of reliable inventories of emissions due to this activity is crucial in order to assess the environmental impact. Presently the official Brazilian emissions inventories do not include the sugarcane pre-harvest burning contribution. Therefore, this work aims to estimate the annual emissions (from 2006 to 2010) associated with pre-harvest sugarcane burning practice in São Paulo state, including the determination of emission factors for some trace gases and particulate material smaller than 2.5 μm. Annual remote sensing based mappings of burned sugarcane fields throughout the harvest season in each crop year made in the context of Canasat Project (http://www.dsr.inpe.br/laf/canasat/en/) were added to the Brazilian Biomass Burning Emission Model (3BEM) in order to estimate trace gases and aerosols emissions. Two laboratory combustion experiments were carried out to determine the emission factors estimation. Samples of different varieties of sugarcane were harvested in dry weather conditions and in distinct sites in the state of São Paulo to assure

  1. Evaluation of representativeness of site-specific fuel-based vehicle emission factors for route average emissions.

    PubMed

    Lee, Taewoo; Frey, H Christopher

    2012-06-19

    An approach to evaluate the representativeness of site-specific fuel-based vehicle emission factors, such as would be obtained using Remote Sensing Devices (RSDs) is demonstrated based on real-world data for 23 selected light duty gasoline vehicles. Real time vehicle route-average emissions rates were measured using a Portable Emissions Measurement System (PEMS) for a variety of road types and traffic characteristics. Several hypothetical remote sensing sites were selected to estimate site-specific fuel-based emission factors. The average fuel-based emission factors increased with vehicle specific power (VSP) and varied by a factor of 3 and 4 for NO(x) and CO, respectively. The route average emission factors varied by approximately 20% for either NO(x) or CO. The site-specific emission factors varied among specific sites by 20 and 30% for NO(x) and CO, respectively. Fuel-based HC emission rates had little variability with engine load, among routes, or between sites. Arbitrarily chosen sites can lead to potential biases for CO and NO(x) if measured emission factors are used for route average rates and, therefore, for area-wide inventories. However, site-specific emission factors have the potential to be representative of area-wide emission rates if the distribution of positive VSP at the site is similar to that of routes or area-wide cycles of interest. PMID:22568568

  2. Emission factors for organic fertilizer-induced N2O emissions from Japanese agricultural soils

    NASA Astrophysics Data System (ADS)

    Sano, T.; Nishina, K.; Sudo, S.

    2013-12-01

    1. Introduction Agricultural fields are significant sources of nitrous oxide (N2O), which is one of the important greenhouse gases with a contribution of 7.9% to the anthropogenic global warming (IPCC, 2007). Direct fertilizer-induced N2O emission from agricultural soil is estimated using the emission factor (EF). National greenhouse gas inventory of Japan defines direct EF for N2O associated with the application of chemical and organic fertilizers as the same value (0.62%) in Japanese agricultural fields. However, it is necessary to estimate EF for organic fertilizers separately, because there are some differences in factors controlling N2O emissions (e.g. nutrient content) between chemical and organic fertilizers. The purpose of this study is to estimate N2O emissions and EF for applied organic fertilizers in Japanese agricultural fields. 2. Materials and Methods We conducted the experiments at 10 prefectural agricultural experimental stations in Japan (Yamagata, Fukushima, Niigata, Ibaraki, Aichi, Shiga, Tokushima, Nagasaki, Kumamoto, and Kagoshima) to consider the variations of cultivation and environmental conditions among regions. Field measurements had been conducted for 2-2.5 years during August 2010-April 2013. Each site set experimental plots with the applications of composted manure (cattle, swine, and poultry), chemical fertilizer, and non-nitrogen fertilizer as a control. The annual amount of applied nitrogen ranged from 16 g-N m-2 y-1 to 60 g-N m-2 y-1 depending on cropping system and cultivated crops (e.g. cabbage, potato) at each site. N2O fluxes were measured using a closed-chamber method. N2O concentrations of gas samples were measured with gas chromatography. The EF value of each fertilizer was calculated as the N2O emission from fertilizer plots minus the background N2O emission (emission from a control plot), and was expressed as a percentage of the applied nitrogen. The soil NH4+ and NO3-, soil temperature, precipitation, and WFPS (water

  3. Ammonia emission factors for the NAPAP (National Acid Precipitation Assessment Program) emission inventory. Final report, January 1985-December 1986

    SciTech Connect

    Misenheimer, D.C.; Warn, T.E.; Zelmanowitz, S.

    1987-01-01

    The report provides information on certain sources of ammonia emissions to the atmosphere for use in the National Acid Precipitation Assessment Program (NAPAP) emission inventories. Major anthropogenic sources of ammonia emissions to the atmosphere are identified, and emission factors for these sources are presented based on a review of the most recent data available. The emission factors developed are used to estimate nationwide emissions for base year 1980 and are compared to ammonia emission factors used in other emission inventories. Major anthropogenic source categories covered are cropland spreading of livestock wastes, beef cattle feedlots, fertilizer manufacture and use, fuel combustion, ammonia synthesis, petroleum refineries, and coke manufacture. Approximately 840,000 tons of ammonia is estimated to have been emitted in the U.S. in 1980; over 64% of which is estimated to have been from livestock wastes.

  4. A laboratory study of agricultural crop residue combustion in China: Emission factors and emission inventory

    NASA Astrophysics Data System (ADS)

    Zhang, Hefeng; Ye, Xingnan; Cheng, Tiantao; Chen, Jianmin; Yang, Xin; Wang, Lin; Zhang, Renyi

    The burning of agricultural crop residue represents a major source of trace gases (CO, CO 2, NO, NO 2, and NO x) and particulate matter on a regional and global scale. This study investigates the gaseous and particulate emissions from the burning of rice, wheat and corn straws, which are three major agricultural crop residues in China, using a self-built burning stove and an aerosol chamber. Emission factors of CO 2, CO, NO, NO 2 and NO x were measured to be 791.3, 64.2, 1.02, 0.79 and 1.81 g kg -1 for rice straw, 1557.9, 141.2, 0.79, 0.32 and 1.12 g kg -1 for wheat straw, and 1261.5, 114.7, 0.85, 0.43 and 1.28 g kg -1 for corn straw, respectively. The corresponding emission factors of particle number are 1.8 × 10 13, 1.0 × 10 13, and 1.7 × 10 13 particles kg -1, respectively. The total emissions of CO, CO 2, and NO x from rice, wheat and corn straw burnings in China for the year 2004 were estimated to be 22.59, 252.92, and 0.28 Tg, respectively. The percentages of CO, CO 2, and NO x to the total emissions were 13.9%, 15.3%, and 31.4% for rice straw, 32.9%, 32.5%, and 20.9% for wheat straw, and 53.2%, 52.2%, and 47.6% for corn straw, respectively. In addition, the emission allocations of agricultural crop residue burning were also plotted in different regions of China using a simple geographic information system (GIS).

  5. VOC emission rates and emission factors for a sheetfed offset printing shop.

    PubMed

    Wadden, R A; Scheff, P A; Franke, J E; Conroy, L M; Javor, M; Keil, C B; Milz, S A

    1995-04-01

    Emission rates were determined during production for a sheetfed offset printing shop by combining the measured concentrations and ventilation rates with mass balance models that characterized the printing space. Air samples were collected simultaneously on charcoal tubes for 12 separate 1-hour periods at 6 locations. Air samples and cleaning solvents were analyzed by gas chromatography for total volatile organic compounds (VOC) and 13 hydrocarbons. The average VOC emission rate was 470 g/hr with a range of 160-1100 g/hr. These values were in good agreement with the amounts of VOC, hexane, toluene, and aromatic C9s determined from estimated solvent usage and measured solvent compositions. Comparison of the emission rates with source activities indicated an emission factor of 30-51 g VOC/press cleaning. Based on the test observations it was estimated that this typical small printing facility was likely to release 1-2 T VOC/year. The methodology also may be useful for the surface coating industry, as emission rates in this study were determined without recourse to a temporary total enclosure and without interfering with worker activities, increasing worker exposure, or increasing safety and explosion hazards. PMID:7726102

  6. Development of emission factors for particulate matter in a school

    SciTech Connect

    Scheff, P.A.; Paulius, V.; Conroy, L.M.

    1999-07-01

    Schools have complex indoor environments which are influenced by many factors such as number of occupants, building design, office equipment, cleaning agents, and school activities. Like large office buildings, school environments may be adversely influenced by deficiencies in ventilation which may be due to improper operation of HVAC systems, attempts at energy efficiency that limit the supply of outdoor air, or remodeling of building components. Most importantly, children spend up to a third of their time in these structures, and thus it is desirable to better understand the environmental quality in these buildings. A middle school (grades 6 to 8) in a residential section of Springfield, IL was selected for this baseline indoor air quality survey. The school was characterized as having no health complaints, good maintenance schedules, and did not contain carpeting within the classrooms or hallways. The focus of this paper is on the measurements of air quality in the school. The development of emission factors for particulate matter is also discussed. Four indoor locations including the Cafeteria, a Science Classroom, an Art Classroom, and the Lobby outside of the main office, and one outdoor location were sampled for various environmental comfort and pollutant parameters for one week in February of 1997. Integrated samples (8 hour sampling time) for respirable and total particulate matter, and short-term measurements of bioaerosols (two minute samples, three times per day) on three consecutive days were collected at each of the indoor and outdoor sites. Continuous measurements of carbon dioxide, carbon monoxide, temperature and humidity were logged at all locations for five days. Continuous measurements of respirable particulate matter were also collected in the Lobby area. Detailed logs of occupant activity were also collected at each indoor monitoring location throughout the study. Total particle concentrations ranged from 29 to 177 {micro}g/m{sup 3} in the art

  7. Human factors engineering for the TERF (Tritium Emissions Reduction Facility) project. [Tritium Emissions Reduction Facility

    SciTech Connect

    Hedley, W.H.; Adams, F.S. ); Wells, J.E. )

    1990-12-14

    The Tritium Emissions Reduction Facility (TERF) is being built by EG G Mound Applied Technologies to provide improved control of the tritium emissions from gas streams being processed. Mound handles tritium in connection with production, development, research, disassembly, recovery, and surveillance operations. During these operations, a small fraction of the tritium being processed escapes from its original containment. The objective of this report is to describe the human factors engineering as performed in connection with the design, construction, and testing of the TERF as required in DOE Order 6430.1A, section 1300-12. Human factors engineering has been involved at each step of the process and was considered during the preliminary research on tritium capture before selecting the specific process to be used. Human factors engineering was also considered in determining the requirements for the TERF and when the specific design work was initiated on the facility and the process equipment. Finally, human factors engineering was used to plan the specific acceptance tests that will be made during TERF installation and after its completion. These tests will verify the acceptability of the final system and its components. 16 refs., 8 figs.

  8. Development of cotton gin PM10 emission factors for EPA’s AP-42

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Compilation of Air Pollution Emission Factors (AP-42) emission factors are assigned ratings, from A (Excellent) to E (Poor), based on the quality of data used to develop them. All current PM10 cotton gin emission factors received quality ratings of D or lower. In an effort to improve these ratin...

  9. Development of cotton gin PM2.5 emission factors for EPA’S AP-42

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Compilation of Air Pollution Emission Factors (AP-42) emission factors are assigned ratings, from A (Excellent) to E (Poor), based on the quality of data used to develop them. AP-42 currently contains no PM2.5 cotton gin emission factors. In an effort to develop science-based data for regulating...

  10. Environmental tobacco smoke: mutagenic emission rates and their relationship to other emission factors

    SciTech Connect

    Lewtas, J.; Williams, K.; Lofroth, G.; Hammond, K.; Leaderer, B.

    1987-05-01

    The objective of this study was to evaluate the emission rates and exposure concentrations of mutagens, nicotine, and particles from cigarettes. Studies were conducted under controlled laboratory and chamber conditions as well as in personal residences. The mutagenicity of environmental tobacco smoke (ETS) was evaluated in three bioassays using two strains of Salmonella typhimurium. Strain TA98 was used in the standard plate-incorporation and microsuspension histidine reversion assays; and strain TM677 in a microsuspension forward mutation assay. The mutagenicity, expressed either per Ug particle or per Ug nicotine, appeared to be a relatively constant factor that did not vary significantly between various cigarette brands. These data are being used to model the emissions of mutagens to predict mutagenic exposure concentrations under various conditions.

  11. Particle number emission factors for an urban highway tunnel

    NASA Astrophysics Data System (ADS)

    Perkins, Jessica L.; Padró-Martínez, Luz T.; Durant, John L.

    2013-08-01

    Exposure to traffic-related air pollution has been linked to increased risks of cardiopulmonary disease, asthma, and reduced lung function. Ultrafine particles (UFP; aerodynamic diameter < 100 nm), one component of traffic exhaust, may contribute to these risks. This paper describes the development of UFP emission factors, an important input parameter for dispersion models used for exposure assessment. Measurements of particle number concentration (PNC), a proxy for UFP, were performed in the Central Artery Tunnel on Interstate-93 in Boston (MA, USA). The tunnel system consists of two, unidirectional bores, which each carry ˜9 × 104 vehicles per day (diesel vehicles comprise 2-5% of the fleet in the southbound tunnel and 1-3% in the northbound tunnel). A tunnel was chosen for study because it provided an enclosed environment where the effects of lateral and vertical dispersion by ambient air and photochemical reactions would be minimized. Data were collected using a mobile platform equipped with rapid-response instruments for measuring PNC (4-3000 nm) as well as NOx. Because Boston is located in a temperate region (latitude 42° N), we were interested in studying seasonal and diurnal differences in emission factors. To characterize seasonal differences, mobile monitoring was performed on 36 days spaced at 7-14 day intervals over one year (Sept. 2010-Sept. 2011); to characterize diurnal differences intensive mobile monitoring (n = 90 total trips through the tunnels) was performed over the course of two consecutive days in January 2012. All data collected during congested traffic conditions (˜7% of total data set) were removed from the analysis. The median PNC inside the two tunnels for all trips during the 12-month campaign was 3-4-fold higher than on I-93 immediately outside the tunnel and 7-10-fold higher than on I-93 4 km from the tunnel. The median particle number emission factors (EFPN) (±median absolute deviation) for the southbound and northbound tunnels

  12. [Estimation of average traffic emission factor based on synchronized incremental traffic flow and air pollutant concentration].

    PubMed

    Li, Run-Kui; Zhao, Tong; Li, Zhi-Peng; Ding, Wen-Jun; Cui, Xiao-Yong; Xu, Qun; Song, Xian-Feng

    2014-04-01

    On-road vehicle emissions have become the main source of urban air pollution and attracted broad attentions. Vehicle emission factor is a basic parameter to reflect the status of vehicle emissions, but the measured emission factor is difficult to obtain, and the simulated emission factor is not localized in China. Based on the synchronized increments of traffic flow and concentration of air pollutants in the morning rush hour period, while meteorological condition and background air pollution concentration retain relatively stable, the relationship between the increase of traffic and the increase of air pollution concentration close to a road is established. Infinite line source Gaussian dispersion model was transformed for the inversion of average vehicle emission factors. A case study was conducted on a main road in Beijing. Traffic flow, meteorological data and carbon monoxide (CO) concentration were collected to estimate average vehicle emission factors of CO. The results were compared with simulated emission factors of COPERT4 model. Results showed that the average emission factors estimated by the proposed approach and COPERT4 in August were 2.0 g x km(-1) and 1.2 g x km(-1), respectively, and in December were 5.5 g x km(-1) and 5.2 g x km(-1), respectively. The emission factors from the proposed approach and COPERT4 showed close values and similar seasonal trends. The proposed method for average emission factor estimation eliminates the disturbance of background concentrations and potentially provides real-time access to vehicle fleet emission factors.

  13. Development of emission factors and emission inventories for motorcycles and light duty vehicles in the urban region in Vietnam.

    PubMed

    Tung, H D; Tong, H Y; Hung, W T; Anh, N T N

    2011-06-15

    This paper reports on a 2-year emissions monitoring program launched by the Centre for Environmental Monitoring of the Vietnam Environment Administration which aimed at determining emission factors and emission inventories for two typical types of vehicle in Hanoi, Vietnam. The program involves four major activities. A database for motorcycles and light duty vehicles (LDV) in Hanoi was first compiled through a questionnaire survey. Then, two typical driving cycles were developed for the first time for motorcycles and LDVs in Hanoi. Based on this database and the developed driving cycles for Hanoi, a sample of 12 representative test vehicles were selected to determine vehicle specific fuel consumption and emission factors (CO, HC, NOx and CO(2)). This set of emission factors were developed for the first time in Hanoi with due considerations of local driving characteristics. In particular, it was found that the emission factors derived from Economic Commission for Europe (ECE) driving cycles and adopted in some previous studies were generally overestimated. Eventually, emission inventories for motorcycles and LDVs were derived by combining the vehicle population data, the developed vehicle specific emission factors and vehicle kilometre travelled (VKT) information from the survey. The inventory suggested that motorcycles contributed most to CO, HC and NOx emissions while LDVs appeared to be more fuel consuming.

  14. [Emission factors of polycyclic aromatic hydrocarbons (PAHs) in residential coal combustion and its influence factors].

    PubMed

    Hai, Ting-Ting; Chen, Ying-Jun; Wang, Yan; Tian, Chong-Guo; Lin, Tian

    2013-07-01

    As the emission source of polycyclic aromatic hydrocarbons (PAHs), domestic coal combustion has attracted increasing attention in China. According to the coal maturity, combustion form and stove type associated with domestic coal combustion, a large-size, full-flow dilution tunnel and fractional sampling system was employed to collect the emissions from five coals with various maturities, which were burned in the form of raw-coal-chunk (RCC)/honeycomb-coal-briquettes (HCB) in different residential stoves, and then the emission factors of PAHs (EF(PAHs)) were achieved. The results indicate that the EF(PAHs) of bituminous coal ranged from 1.1 mg x kg(-1) to 3.9 mg x kg(-1) for RCC and 2.5 mg x kg(-1) to 21. 1 mg x kg(-1) for HCB, and the anthracite EF(PAH8) were 0.2 mg x kg(-1) for RCC and 0.6 mg x kg(-1) for HCB, respectively. Among all the influence factors of emission factors of PAHs from domestic coal combustion, the maturity of coal played a major role, the range of variance reaching 1 to 2 orders of magnitude in coals with different maturity. Followed by the form of combustion (RCC/HCB), the EF(PAHs) of HCB was 2-6 times higher than that of RCC for the same geological maturity of the coal. The type of stove had little influence on EF(PAHs).

  15. Direct measurements of the seasonality of emission factors from savanna fires in northern Australia

    NASA Astrophysics Data System (ADS)

    Meyer, C. P.; Cook, G. D.; Reisen, F.; Smith, T. E. L.; Tattaris, M.; Russell-Smith, J.; Maier, S. W.; Yates, C. P.; Wooster, M. J.

    2012-10-01

    Current good practice guidelines for national greenhouse gas inventories requires that seasonal variation in emission factors from savanna fires be considered when compiling national accounts. African studies concluded that the emission factor for methane decreases during the dry season principally due to curing of the fuels. However, available data from Australian tropical savannas shows no effect of seasonality on emission factors, consistent with observations that the fine fuels appear to cure fully soon after the start of the fire season. To test whether the seasonality in greenhouse gas emission factors reported for Africa also occurs in Australia, methane and nitrous oxide emission factors were measured in early and in late dry season fires in Western Arnhem Land, a region typical of much of the northern Australia savanna zone. We found no significant seasonality in methane emission factors, but there was substantial variation in emission factors associated with inter-fire differences in vegetation and fuel. This variation could be explained almost completely by combustion efficiency. Nitrous oxide emission factors were not related to combustion efficiency but showed some variation across vegetation and fuel size class. Both methane and nitrous oxide emission factors were consistent with previous work in northern Australia and with some published values from Africa. The absence of a significant seasonal trend in emission factors indicates that savanna fire emissions in northern Australia can be managed by strategic prescribed burning.

  16. Emission factor development for the malt beverage, wine, and distilled spirits industries

    SciTech Connect

    Lapp, T.; Shrager, B.; Safriet, D.

    1996-12-31

    Midwest Research Institute is currently developing emission factors for inclusion in AP-42 Chapter 9, Food and Agricultural Industries. Three of the sections cover the production of malt beverages, wine, and distilled spirits. The malt beverage segment focuses on the development of ethanol emission factors for filling operations, which were recently identified as the large source of brewery ethanol emissions. The discussion includes a description of the production process and emissions factors for breweries, a history of emission factories for breweries, a description of emission testing conducted at two large breweries, and a presentation of some of the emission factors for malt beverage production. The wine industry segment focuses on emissions from the fermentation stage for red and white wines, the pomace screen and pomace press for red wines, and bottling of white wine. Emission factors are presented for ethanol emissions from each of these sources as well as other VOC emissions from the fermentation process. A discussion of the wine production process is presented. A discussion of the emission sources and available emission factors is presented for the distilled spirits industry segment. Factors are presented for the fermentation and aging stages. A process description is presented for the production of Bourbon whisky.

  17. On-road remote sensing of petrol vehicle emissions measurement and emission factors estimation in Hong Kong

    NASA Astrophysics Data System (ADS)

    Chan, T. L.; Ning, Z.; Leung, C. W.; Cheung, C. S.; Hung, W. T.; Dong, G.

    In the present study, the real world on-road petrol vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitric oxide (NO) were investigated at nine sites in Hong Kong. A regression analysis approach based on the measured petrol vehicle emission data was also used to estimate the on-road petrol vehicle emission factors of CO, HC and NO with respect to the effects of instantaneous vehicle speed and acceleration/deceleration profiles for local urban driving patterns. The results show that the petrol vehicle model years, engine sizes and driving patterns have a strong correlation on their emission factors. A comparison of average petrol vehicle emission factors in different engine sizes and European vehicle emission standards was also presented. The deviation of the average emission factors of aggregate petrol vehicle reflects on the variability of local road condition, vehicle traffic fleet and volume, driving pattern, fuel composition and ambient condition etc. Finally, a unique database of the correlation of petrol vehicle emission factors on different model years and engine sizes for urban driving patterns in Hong Kong was established.

  18. Combustion efficiency and emission factors for US wildfires

    NASA Astrophysics Data System (ADS)

    Urbanski, S. P.

    2013-01-01

    In the US wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with National Ambient Air Quality Standards (NAAQS) and Regional Haze Regulations. Wildland fire emission inventories (EI) provide critical inputs for atmospheric chemical transport models used by air regulatory agencies to understand and to predict the impact of fires on air quality. Fire emission factors (EF), which quantify the amount of pollutants released per mass of biomass burned, are essential input for the emission models used to develop EI. Over the past decade substantial progress has been realized in characterizing the composition of fresh biomass burning (BB) smoke and in quantifying BB EF. However, most BB studies of temperate ecosystems have focused on emissions from prescribed burning. Little information is available on EF for wildfires in the temperate forests of the conterminous US. Current emission estimates for US wildfires rely largely on EF measurements from prescribed burns and it is unknown if these fires are a reasonable proxy for wildfires. Over 8 days in August of 2011 we deployed airborne chemistry instruments and sampled emissions from 3 wildfires and a prescribed fire that occurred in mixed conifer forests of the northern Rocky Mountains. We measured the combustion efficiency, quantified as the modified combustion efficiency (MCE), and EF for CO2, CO, and CH4. Our study average values for MCE, EFCO2, EFCO, and EFCH4 were 0.883, 1596 g kg-1, 135 g kg-1, 7.30 g kg-1, respectively. Compared with previous field studies of prescribed fires in similar forest types, the fires sampled in our study had significantly lower MCE and EFCO2 and significantly higher EFCO and EFCH4. An examination of our study and 47 temperate forest prescribed fires from previously published studies shows a clear trend in MCE across US region/fire type: southeast (MCE = 0.933) > southwest (MCE = 0.922) > northwest (MCE = 0

  19. On-road remote sensing of liquefied petroleum gas (LPG) vehicle emissions measurement and emission factors estimation

    NASA Astrophysics Data System (ADS)

    Ning, Z.; Chan, T. L.

    In the present study, the real-world on-road liquefied petroleum gas (LPG) vehicle/taxi emissions of carbon monoxide (CO), hydrocarbon (HC) and nitric oxide (NO) were investigated. A regression analysis approach based on the measured LPG vehicle emission data was also used to estimate the on-road LPG vehicle emission factors of CO, HC and NO with respect to the effects of instantaneous vehicle speed and acceleration/deceleration profiles for local urban driving patterns. The results show that the LPG vehicle model years and driving patterns have a strong correlation to their emission factors. A unique correlation of LPG vehicle emission factors (i.e., g km -1 and g l -1) on different model years for urban driving patterns has been established. Finally, a comparison was made between the average LPG, and petrol [Chan, T.L., Ning, Z., Leung, C.W., Cheung, C.S., Hung, W.T., Dong, G., 2004. On-road remote sensing of petrol vehicle emissions measurement and emission factors estimation in Hong Kong. Atmospheric Environment 38, 2055-2066 and 3541] and diesel [Chan, T.L., Ning, Z., 2005. On-road remote sensing of diesel vehicle emissions measurement and emission factors estimation in Hong Kong. Atmospheric Environment 39, 6843-6856] vehicle emission factors. It has shown that the introduction of the replacement of diesel taxis to LPG taxis has alleviated effectively the urban street air pollution. However, it has demonstrated that proper maintenance on the aged LPG taxis should also be taken into consideration.

  20. Emission factor development for the brick and related clay products industry

    SciTech Connect

    Shrager, B.; Marinshaw, R.; Myers, R.

    1996-12-31

    Midwest Research Institute (MRI), under contract to the United States Environmental Protection Agency (EPA), is currently revising Section 11.3, Bricks and Related Clay Products, of EPA`s Compilation of Air Pollutant Emission Factors (AP-42). This paper presents an overview of the development of this AP-42 section and includes a discussion of the brick manufacturing process, emissions, an EPA-sponsored emission testing program, industry involvement in the project, and the development of revised emission factors that are proposed for publication. The paper also discusses some unanticipated results of the emission testing (the SO{sub 2} emission measurements from a natural gas-fired kiln were significantly higher than SO{sub 2} measurements from a coal-fired kiln) and the reasons for these results. Finally, some of the major differences in the current and proposed emission factors are highlighted, and the proposed emission factors are presented.

  1. On-road remote sensing of diesel vehicle emissions measurement and emission factors estimation in Hong Kong

    NASA Astrophysics Data System (ADS)

    Chan, T. L.; Ning, Z.

    In the present study, the real world on-road diesel vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitric oxide (NO) were investigated at nine sites in Hong Kong. A regression analysis approach based on the measured vehicle emission data was used to estimate the on-road diesel vehicle emission factors of CO, HC and NO with respect to the effects of instantaneous vehicle speed and acceleration/deceleration profiles for local urban driving patterns. The results show that the diesel vehicle model years, engine sizes, vehicle types and driving patterns have a strong correlation with their emission factors. A comparison was made between the average diesel and petrol vehicle emissions factors in Hong Kong. The deviation of the average emission factors of aggregate diesel vehicles reflects the variability of local road condition, vehicle traffic fleet and volume, driving pattern, fuel composition and ambient condition etc. Finally, a unique database of the correlation of diesel vehicle emission factors (i.e., g km -1 and g l -1) on different model years and vehicle types for urban driving patterns in Hong Kong was established.

  2. Use of portable emissions measurement system (PEMS) for the development and validation of passenger car emission factors

    NASA Astrophysics Data System (ADS)

    Kousoulidou, Marina; Fontaras, Georgios; Ntziachristos, Leonidas; Bonnel, Pierre; Samaras, Zissis; Dilara, Panagiota

    2013-01-01

    This paper discusses the development and validation of passenger car emission factors, using real world operation data. In total, six passenger cars of different technologies were studied. The tested vehicles were operated under various driving conditions and over two different routes in the region of Lombardia, Italy. These routes were specifically defined in order to provide a range of driving conditions, including urban, rural and highway driving. Tailpipe emissions and exhaust gas flows were measured on-board the vehicle, using a portable emissions measurement system (PEMS). In addition, all vehicles were tested over the European type-approval driving cycle (NEDC) with the same PEMS equipment. The testing of gasoline vehicles showed that emissions are well below the emission standards and do not raise any concern. However, the testing of diesel vehicles both under real-world driving conditions and over the NEDC brought to the surface important concerns regarding the actual NOx emissions of modern diesel vehicles, since they seem to comply with the corresponding emission standard over the type-approval cycle, but they constantly exceed the specified limit when tested under real-world driving conditions. Results from real-world operation revealed that there is a significant deviation from the NOx emission standard limit (especially for the newly introduced Euro 5 technology). These observations raise concerns regarding the actual NOx emissions of modern vehicles and their impact on urban air-quality. The emission factors originally measured on the road are also compared to the corresponding COPERT average speed emission factors. In general, emissions of CO2, THC and CO correlate fairly well with COPERT, for all vehicles. In the case of NOx emissions, emission levels of the two tested Euro 5 diesel passenger cars are consistently higher in urban, rural, and highway driving compared to the corresponding COPERT emission factor. Thus, leading to the conclusion that

  3. 40 CFR 63.1431 - Process vent annual epoxides emission factor plan requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... factor plan requirements. 63.1431 Section 63.1431 Protection of Environment ENVIRONMENTAL PROTECTION... Polyether Polyols Production § 63.1431 Process vent annual epoxides emission factor plan requirements. (a) Applicability of emission factor plan requirements. An owner or operator electing to comply with an...

  4. 40 CFR Table U-1 to Subpart U of... - CO2 Emission Factors for Common Carbonates

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false CO2 Emission Factors for Common.... 98, Subpt. U, Table U-1 Table U-1 to Subpart U of Part 98—CO2 Emission Factors for Common Carbonates Mineral name—carbonate CO2 emission factor(tons CO2/ton carbonate) Limestone—CaCO3 0.43971...

  5. 40 CFR Table U-1 to Subpart U of... - CO2 Emission Factors for Common Carbonates

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false CO2 Emission Factors for Common.... 98, Subpt. U, Table U-1 Table U-1 to Subpart U of Part 98—CO2 Emission Factors for Common Carbonates Mineral name—carbonate CO2 emission factor(tons CO2/ton carbonate) Limestone—CaCO3 0.43971...

  6. 40 CFR Table U-1 to Subpart U of... - CO2 Emission Factors for Common Carbonates

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false CO2 Emission Factors for Common.... 98, Subpt. U, Table U-1 Table U-1 to Subpart U of Part 98—CO2 Emission Factors for Common Carbonates Mineral name—carbonate CO2 emission factor(tons CO2/ton carbonate) Limestone—CaCO3 0.43971...

  7. 40 CFR Table U-1 to Subpart U of... - CO2 Emission Factors for Common Carbonates

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false CO2 Emission Factors for Common.... 98, Subpt. U, Table U-1 Table U-1 to Subpart U of Part 98—CO2 Emission Factors for Common Carbonates Mineral name—carbonate CO2 emission factor(tons CO2/ton carbonate) Limestone—CaCO3 0.43971...

  8. Update on the development of cotton gin PM2.5 emission factors for EPA's AP-42

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cotton ginning industry-supported project was initiated in 2008 to update the U.S. Environmental Protection Agency’s (EPA) Compilation of Air Pollution Emission Factors (AP-42) to include PM2.5 emission factors. This study develops emission factors from the PM2.5 emission factor data collected fro...

  9. Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

    PubMed

    Jacobsen, Grant D

    2014-06-17

    This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies.

  10. Estimating end-use emissions factors for policy analysis: the case of space cooling and heating.

    PubMed

    Jacobsen, Grant D

    2014-06-17

    This paper provides the first estimates of end-use specific emissions factors, which are estimates of the amount of a pollutant that is emitted when a unit of electricity is generated to meet demand from a specific end-use. In particular, this paper provides estimates of emissions factors for space cooling and heating, which are two of the most significant end-uses. The analysis is based on a novel two-stage regression framework that estimates emissions factors that are specific to cooling or heating by exploiting variation in cooling and heating demand induced by weather variation. Heating is associated with similar or greater CO2 emissions factor than cooling in all regions. The difference is greatest in the Midwest and Northeast, where the estimated CO2 emissions factor for heating is more than 20% larger than the emissions factor for cooling. The minor differences in emissions factors in other regions, combined with the substantial difference in the demand pattern for cooling and heating, suggests that the use of overall regional emissions factors is reasonable for policy evaluations in certain locations. Accurately quantifying the emissions factors associated with different end-uses across regions will aid in designing improved energy and environmental policies. PMID:24866122

  11. Pollutant Emission Factors from Residential Natural Gas Appliances: A Literature Review

    SciTech Connect

    Traynor, G.W.; Apte, M.G.; Chang, G.-M.

    1996-08-01

    There is a need to reduce air pollutant emissions in some U.S. urban regions to meet federal and state air quality guidelines. Opportunities exist for reducing pollutant emissions from natural gas appliances in the residential sector. A cost-benefit analysis on various pollutant-reducing strategies is needed to evaluate these opportunities. The effectiveness of these pollutant-reducing strategies (e.g., low-emission burners, energy conservation) can then be ranked among themselves and compared with other pollutant-reducing strategies available for the region. A key step towards conducting a cost-benefit analysis is to collect information on pollutant emissions from existing residential natural gas appliances. An extensive literature search was conducted to collect data on residential natural-gas-appliance pollutant emission factors. The literature primarily describes laboratory tests and may not reflect actual emission factor distributions in the field. Pollutant emission factors for appliances operated at over 700 test conditions are summarized for nitrogen oxides, carbon monoxide, fine particulate matter, formaldehyde, and methane. The appliances for which pollutant emissions are summarized include forced-air furnaces; stand-alone space heaters (vented and unvented); water heaters; cooking range burners, ovens, and broilers; and pilot lights. The arithmetic means of the nitrogen oxides and fine particulate matter emission factor distributions agree well with the Environmental Protection Agency published emission factor values for domestic gas appliances (in report AP-42). However, the carbon monoxide and methane distribution means are much higher than the relevant AP-42 values. Formaldehyde emission factors are not addressed in AP-42, but the emission factor mean for formaldehyde is comparable to the AP-42 emission factor value for total hydrocarbon emissions.

  12. 76 FR 71559 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-18

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  13. 78 FR 64496 - Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-29

    ... AGENCY Acid Rain Program: Notice of Annual Adjustment Factors for Excess Emissions Penalty AGENCY.... SUMMARY: The Acid Rain Program under title IV of the Clean Air Act provides for automatic excess emissions penalties in dollars per ton of excess emissions for sources that do not meet their annual Acid...

  14. Evaluation of speciated VOC emission factors for Air Force hush houses

    SciTech Connect

    Sullivan, P.D.; Stevens, D.K.

    1997-12-31

    Data published in: ``Engine and Hush House Emissions from a TF30-P109 Jet Engine Tested at Cannon Air Force Base, NM`` by Radian Corporation and ``Aircraft Emissions. Characterization: TF41-A2, TF30-P103 , and TF30-P109 Engines`` by Battelle are reviewed and compared. Specifically CO, NO{sub x}, and VOC emission factors using EPA Method 19 are addressed, with comparisons between JP-4 and JP-8 jet fuels. CO and NO{sub x} emissions for JP-4 and JP-8 jet fuels were found to be essentially the same. VOC emission data exhibited high variability. Problems inherent in speciated VOC emission testing are discussed. A limiting of speciated VOC emission testing, with emission factor estimation based on fuel content is proposed.

  15. Development and preliminary evaluation of a particulate matter emission factor model for European motor vehicles.

    PubMed

    Singh, R B; Colls, J J

    2000-10-01

    Although modeling of gaseous emissions from motor vehicles is now quite advanced, prediction of particulate emissions is still at an unsophisticated stage. Emission factors for gasoline vehicles are not reliably available, since gasoline vehicles are not included in the European Union (EU) emission test procedure. Regarding diesel vehicles, emission factors are available for different driving cycles but give little information about change of emissions with speed or engine load. We have developed size-specific speed-dependent emission factors for gasoline and diesel vehicles. Other vehicle-generated emission factors are also considered and the empirical equation for re-entrained road dust is modified to include humidity effects. A methodology is proposed to calculate modal (accelerating, cruising, or idling) emission factors. The emission factors cover particle size ranges up to 10 microns, either from published data or from user-defined size distributions. A particulate matter emission factor model (PMFAC), which incorporates virtually all the available information on particulate emissions for European motor vehicles, has been developed. PMFAC calculates the emission factors for five particle size ranges [i.e., total suspended particulates (TSP), PM10, PM5, PM2.5, and PM1] from both vehicle exhaust and nonexhaust emissions, such as tire wear, brake wear, and re-entrained road dust. The model can be used for an unlimited number of roads and lanes, and to calculate emission factors near an intersection in user-defined elements of the lane. PMFAC can be used for a variety of fleet structures. Hot emission factors at the user-defined speed can be calculated for individual vehicles, along with relative cold-to-hot emission factors. The model accounts for the proportions of distance driven with cold engines as a function of ambient temperature and road type (i.e., urban, rural, or motorway). A preliminary evaluation of PMFAC with an available dispersion model to predict

  16. Carbon dioxide emission factors for U.S. coal by origin and destination

    USGS Publications Warehouse

    Quick, J.C.

    2010-01-01

    This paper describes a method that uses published data to calculate locally robust CO2 emission factors for U.S. coal. The method is demonstrated by calculating CO2 emission factors by coal origin (223 counties, in 1999) and destination (479 power plants, in 2005). Locally robust CO2 emission factors should improve the accuracy and verification of greenhouse gas emission measurements from individual coal-fired power plants. Based largely on the county origin, average emission factors for U.S. lignite, subbituminous, bituminous, and anthracite coal produced during 1999 were 92.97,91.97,88.20, and 98.91 kg CO2/GJgross, respectively. However, greater variation is observed within these rank classes than between them, which limits the reliability of CO2 emission factors specified by coal rank. Emission factors calculated by destination (power plant) showed greater variation than those listed in the Emissions & Generation Resource Integrated Database (eGRID), which exhibit an unlikely uniformity that is inconsistent with the natural variation of CO2 emission factors for U.S. coal. ?? 2010 American Chemical Society.

  17. Pollutant-emission factors for gas stoves: a literature survey. Final report, June 1985-May 1986

    SciTech Connect

    Davidson, C.I.; Borrazzo, J.E.; Hendrickson, C.T.

    1987-02-01

    Published emission factors for CO, NO, NO/sub 2/, and NOx are summarized. In a statistical analysis of the available data, stove differences and type of combustion are the most important factors in explaining the observed variance in emission factors. Limited data also suggest that CO and NO/sub 2/ emission factors vary considerably with gas flow rate. It is concluded that the influence of stove design, gas flow rate, and characteristics of stove use are key factors that merit further study.

  18. Calculated 1993 emission factors of trace metals for Canadian non-ferrous smelters

    NASA Astrophysics Data System (ADS)

    Skeaff, J. M.; Dubreuil, A. A.

    Emission factors of As, Cd, Cu, Hg, Mn, Ni, Pb, Sb, Se and Zn from the Canadian primary non-ferrous smelting industry have been calculated from publicly available 1993 emission release data and metal production data. With a few exceptions, the calculated weighted average 1993 emission factors for the Canadian non-ferrous metals industry are between approximately 40% and more than 1500 times lower than published emission factors of As, Cd, Cu, Hg, Mn, Ni, Pb, Sb, Se and Zn used in the literature to estimate global inventories of emissions from the world non-ferrous smelting sector. Where comparisons are possible, these calculated emission factors validate, with two exceptions, the EMEP/CORINAIR values suggested to estimate release inventories from lead and copper ( + nickel) production; however, use of the EMEP/CORINAIR values for zinc production would considerably overestimate the releases from the primary Canadian zinc industry.

  19. Compilation of air pollutant emission factors, third edition (including supplements 1-7) supplement 12

    SciTech Connect

    Not Available

    1981-04-01

    In this Supplement for AP-42, revised or updated emissions data are presented for Dry Cleaning; Surface Coating; Storage of Organic Liquids; Solvent Degreasing; Graphic Arts; Consumer/commercial Solvent Use; Sulfuric Acid; Beer Making; Ammonium Sulfate; Primary Aluminum; Secondary Aluminum; Gray Iron Foundries; Steel Foundries; Secondary Zinc; Asphaltic Concrete; Asphalt Roofing; NEDS Source Classification Codes and Emission Factor Listing; and Table of Lead Emission Factors.

  20. DEVELOPMENT OF HAZARDOUS AIR POLLUTANT EMISSION FACTORS FROM STATE SOURCE TEST PROGRAMS

    EPA Science Inventory

    The report gives results of a study in which emission factors were evolved from test data obtained from several Air Quality Management Districts in California and from state environmental agencies in Louisiana, Maryland, New Jersey, and Texas. The emission factors were developed...

  1. 40 CFR Table O-1 to Subpart O of... - Emission Factors for Equipment Leaks

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Emission Factors for Equipment Leaks O Table O-1 to Subpart O of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Pt. 98, Subpt. O, Table O-1 Table O-1 to Subpart O of Part 98—Emission Factors for Equipment...

  2. 40 CFR Table O-1 to Subpart O of... - Emission Factors for Equipment Leaks

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Emission Factors for Equipment Leaks O Table O-1 to Subpart O of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Pt. 98, Subpt. O, Table O-1 Table O-1 to Subpart O of Part 98—Emission Factors for Equipment...

  3. 40 CFR Table O-1 to Subpart O of... - Emission Factors for Equipment Leaks

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Emission Factors for Equipment Leaks O Table O-1 to Subpart O of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Pt. 98, Subpt. O, Table O-1 Table O-1 to Subpart O of Part 98—Emission Factors for Equipment...

  4. 40 CFR Table O-1 to Subpart O of... - Emission Factors for Equipment Leaks

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Emission Factors for Equipment Leaks O Table O-1 to Subpart O of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Pt. 98, Subpt. O, Table O-1 Table O-1 to Subpart O of Part 98—Emission Factors for Equipment...

  5. DEVELOPMENT OF ON-ROAD EMISSION FACTORS FOR HEAVY- DUTY VEHICLES

    EPA Science Inventory

    The paper discusses an EPA project the objectives of which are to: (1) define on-road emissions from heavy-duty diesel vehicles (HDDVs); (2) assess agreement between engine and chassis dynamometers and on-road emission factors; (3) evaluate current conversion factors for dynamome...

  6. Key factors, Soil N Processes, and nitrite accumulation affecting nitrous oxide emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A better understanding of the key factors affecting nitrous oxide (N2O) emission and potential mitigation strategies is essential for sustainable agriculture. The objective of this study was to examine the important factors affecting N2O emissions, soil processes involved, and potential mitigation s...

  7. EMISSION FACTORS FOR IRON AND STEEL SOURCES: CRITERIA AND TOXIC POLLUTANTS

    EPA Science Inventory

    The report provides a comprehensive set of emission factors for sources of both criteria and toxic air pollutants in integrated iron and steel plants and specialty electric arc shops (minimills). Emission factors are identified for process sources, and process and open source fug...

  8. 40 CFR Table W - 6 of Subpart W-Default Methane Emission Factors for LNG Import and Export Equipment

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Factors for LNG Import and Export Equipment W Table W Protection of Environment ENVIRONMENTAL... Emission Factors for LNG Import and Export Equipment LNG import and export equipment Emission factor (scf/hour/component) Leaker Emission Factors—LNG Terminals Components, LNG Service Valve 1.19 Pump Seal...

  9. Characterization of emissions from portable household combustion devices: particle size distributions, emission rates and factors, and potential exposures

    NASA Astrophysics Data System (ADS)

    Fan, Cheng-Wei; Zhang, Junfeng (Jim)

    A series of source tests were conducted to characterize emissions of particulate matter (PM), carbon monoxide (CO), carbon dioxide (CO 2), methane (CH 4), and total hydrocarbon (THC ) from five types of portable combustion devices. Tested combustion devices included a kerosene lamp, an oil lamp, a kerosene space heater, a portable gas range, and four unscented candles. All tests were conducted either in a well-mixed chamber or a well-mixed room, which enables us to determine emission rates and emission factors using a single-compartment mass balance model. Particle mass concentrations and number concentrations were measured using a nephelometric particle monitor and an eight-channel optical particle counter, respectively. Real-time CO concentrations were measured with an electrochemical sensor CO monitor. CO 2, CH 4, and THC were measured using a GC-FID technique. The results indicate that all particles emitted during steady burning in each of the tested devices were smaller than 1.0 μm in diameter with the vast majority in the range between 0.1 and 0.3 μm. The PM mass emission rates and emission factors for the tested devices ranged from 5.6±0.1 to 142.3±40.8 mg h -1 and from 0.35±0.06 to 9.04±4.0 mg g -1, respectively. The CO emission rates and emission factors ranged from 4.7±3.0 to 226.7±100 mg h -1 and from 0.25±0.12 to 1.56±0.7 mg g -1, respectively. The CO 2 emission rates and emission factors ranged from 5500±700 to 210,000±90,000 mg h -1 and from 387±45 to 1689±640 mg g -1, respectively. The contributions of CH 4 and THC to emission inventories are expected to be insignificant due both to the small emission factors and to the relatively small quantity of fuel consumed by these portable devices. An exposure scenario analysis indicates that every-day use of the kerosene lamp in a village house can generate fine PM exposures easily exceeding the US promulgated NAAQS for PM 2.5.

  10. Factors controlling natural VOC emissions in a southeastern US pine forest

    NASA Astrophysics Data System (ADS)

    Kim, Jo-Chun

    A one-year field study was conducted to investigate the control factors of the monoterpene emissions from slash and loblolly pine saplings at the Austin Cary Forest site in Florida. The α-pinene, camphene, β-pinene, myrcene, d-limonene, and β-phellandrene were identified in the emission samples collected from native pine trees. The α-pinene was the principal (>60%) monoterpene emitted by both slash and loblolly pine saplings. Terpene emission rates in spring were the highest and most volatile for slash pine trees, possibly due to the influences of bud formation and elongation. Loblolly pine emissions, under a similar environmental temperature range, revealed different seasonal patterns of emissions when compared to those for slash pines. Emission rates of monoterpenes from slash and loblolly pine trees were found to depend on temperature, season's change (e.g., bud emissions), tree age, needle surface wetness, and rough handling. It is suggested that the emission control factors besides the environmental temperature should also be taken into account in assessing regional biogenic emissions for compling a worldwide hydrocarbon emission inventory. It is also found that monoterpene emission rates could easily change over a long period of time (e.g., years), and so it is desirable to analyze the emission data based on the short term (e.g., season, month) for reasonable temperature-emission algorithm.

  11. New estimates of direct N2O emissions from Chinese croplands from 1980 to 2007 using localized emission factors

    NASA Astrophysics Data System (ADS)

    Gao, B.; Ju, X. T.; Zhang, Q.; Christie, P.; Zhang, F. S.

    2011-07-01

    Nitrous oxide (N2O) is a long-lived greenhouse gas with a large radiation intensity and it is emitted mainly from agricultural land. Accurate estimates of total direct N2O emissions from croplands on a country scale are important for global budgets of anthropogenic sources of N2O emissions and for the development of effective mitigation strategies. The objectives of this study were to re-estimate direct N2O emissions using localized emission factors and a database of measurements from Chinese croplands. We obtained N2O emission factors for paddy fields (0.41 %) and uplands (1.05 %) from a normalization process through cube root transformation of the original data after comparing the results of normalization from the original values, logarithmic and cube root transformations because the frequency of the original data was not normally distributed. Direct N2O emissions from Chinese croplands from 1980 to 2007 were estimated using IPCC (2006) guidelines combined with separate localized emission factors for paddy fields and upland areas. Direct N2O emissions from paddy fields showed little change, increasing by 11 % with an annual rate of increase of 0.4 % from 29.8 Gg N2O-N in 1980 to 33.1 Gg N2O-N in 2007. In contrast, emissions from uplands changed dramatically, increasing by 296 % with an annual rate of 10.9 % from 64.4 Gg N2O-N in 1980 to 255.3 Gg N2O-N in 2007. Total direct N2O emissions from Chinese croplands increased by 206 % with an annual rate of 7.6 % from 94.2 Gg N2O-N in 1980 to 288.4 Gg N2O-N in 2007, and were determined mainly by upland emissions (accounting for 68.4-88.5 % of total emissions from 1980 to 2007). Synthetic nitrogen fertilizers played a major role in N2O emissions from agricultural land, and the magnitude of the contributions to total direct N2O emissions made by different amendments was synthetic N fertilizer > manure > straw, representing about 77, 16, and 6.5 % of total direct N2O emissions, respectively, between 2000 and 2007. The

  12. New estimates of direct N2O emissions from Chinese croplands from 1980 to 2007 using localized emission factors

    NASA Astrophysics Data System (ADS)

    Gao, B.; Ju, X. T.; Zhang, Q.; Christie, P.; Zhang, F. S.

    2011-10-01

    Nitrous oxide (N2O) is a long-lived greenhouse gas with a large radiation intensity and it is emitted mainly from agricultural land. Accurate estimates of total direct N2O emissions from croplands on a country scale are important for global budgets of anthropogenic sources of N2O emissions and for the development of effective mitigation strategies. The objectives of this study were to re-estimate direct N2O emissions using localized emission factors and a database of measurements from Chinese croplands. We obtained N2O emission factors for paddy fields (0.41 ± 0.04%) and uplands (1.05 ± 0.02%) from a normalization process through cube root transformation of the original data. After comparing the results of normalization from the original values, Logarithmic and cube root transformations were used because the frequency of the original data was not normally distributed. Direct N2O emissions from Chinese croplands from 1980 to 2007 were estimated using IPCC (2006) guidelines combined with separate localized emission factors for paddy fields and upland areas. Direct N2O emissions from paddy fields showed little change, increasing by 10.5% with an annual rate of increase of 0.4% from 32.3 Gg N2O-N in 1980 to 35.7 Gg N2O-N in 2007. In contrast, emissions from uplands changed dramatically, increasing by 308% with an annual rate of 11% from 68.0 Gg N2O-N in 1980 to 278 Gg N2O-N in 2007. Total direct N2O emissions from Chinese croplands increased by 213% with an annual rate of 7.6% from 100 Gg N2O-N in 1980 to 313 Gg N2O-N in 2007, and were determined mainly by upland emissions (accounting for 67.8-88.6% of total emissions from 1980 to 2007). Synthetic N fertilizers played a major role in N2O emissions from agricultural land, and the magnitude of the contributions to total direct N2O emissions made by different amendments was synthetic N fertilizer > manure > straw, representing about 78, 15, and 6% of total direct N2O emissions, respectively, between 2000 and 2007. The

  13. A comparison of state-level estimation techniques for utility atmospheric emission factors

    SciTech Connect

    Schrock, D.; Baechler, M.

    1995-10-01

    Atmospheric emission factors provide a link between the electricity saved in buildings and the associated decrease in fossil fuel use in the electric supply sector. Understanding this link is important to meet the requirements of Section 1605(b) of the Energy Policy act of 1992, which established the voluntary program for reporting reductions in greenhouse gases. As part of the development process for Section 1605(b), several national workshops were held by the US Department of Energy (DOE) and the Energy Information Administration (EIA). Workshop participants expressed the need for DOE to supply default atmospheric emission facets. Based upon the response from the workshop participants, it was decided that emission factors would be aggregated to the state level (e.g., California, Connecticut, etc.). Emission factors for electricity generation are generally quantified as a quantity of impact to an amount of fuel used to produce the emission. In the electric supply sector, factors are often expressed in units of pounds or tons of emission per megawatt-hours (MWh) of electricity produced. In this paper, the authors examine and compare the estimates from three methodologies for developing state-level emission facets. In addition, they compare the results to those obtained using emissions data calculated by the EIA. Although the examples presented in this paper depict the development of state-level factors, the same methodologies can be applied by an individual utility to generate utility-specific atmospheric emission factors.

  14. Emission factors for heavy metals from diesel and petrol used in European vehicles

    NASA Astrophysics Data System (ADS)

    Pulles, Tinus; Denier van der Gon, Hugo; Appelman, Wilfred; Verheul, Marc

    2012-12-01

    Heavy metals constitute an important group of persistent toxic pollutants occurring in ambient air and other media. One of the suspected sources of these metals in the atmosphere is combustion of transport fuels in road vehicles. However, estimates of the emissions of these metals from road vehicles as reported in national emission inventories show a very high variability in emission factors used. This paper provides high quality data on concentrations of heavy metals in fuels and derives default emission factors from these. The paper discusses these values against the emission estimates presently reported by the Parties to the LRTAP Convention. The measured concentrations of heavy metals in petrol and diesel fuel show a high variability between different samples taken at gas stations throughout Europe. Metal concentrations in road transport fuels vary over two orders of magnitude, but all remain in the ppb region (a few tenths of a ppb to a few hundred ppb for all metals). The frequency distributions of the measurements could be approximated by lognormal distributions. The emission factors, including 95 percent confidence intervals were derived from a statistical analysis of the survey data. We could not detect a significant difference between samples from different countries. The fuel based emission factors as derived in this study are complemented with those related to unintentional lubricant oil combustion. This allowed an estimation of total exhaust heavy metal emissions for UNECE Europe, indicating that As, Hg and Se exhaust emissions were dominated by fuel combustion while Cd, Cr, Cu, Ni, Pb, and Zn exhaust emissions were dominated by lubricant oil combustion. The proposed emission factors were generally lower than previously published emission factors. National emissions of heavy metals from vehicle exhaust, estimated in this study are in many cases considerably lower than those reported by the countries for this source.

  15. Factors controlling emissions of dimethylsulphide from salt marshes

    NASA Technical Reports Server (NTRS)

    Dacey, John W. H.; Wakeham, Stuart G.; King, Gary M.

    1987-01-01

    Salt marshes are presently identified as systems exhibiting high area-specific sulfur emission in the form of dimethylsulfide (DMS) and H2S, with the former predominating in vegetated areas of the marshes. Attention is presently given to the distribution of DMS in salt marshes; it is found that this compound primarily arises from physiological processes in the leaves of higher plants, especially the grass species Spartina alterniflora. Uncertainties associated with DMS emission measurements are considered.

  16. Empirical model of odor emission from deep-pit swine finishing barns to derive a standardized odor emission factor

    NASA Astrophysics Data System (ADS)

    Schauberger, Günther; Lim, Teng-Teeh; Ni, Ji-Qin; Bundy, Dwaine S.; Haymore, Barry L.; Diehl, Claude A.; Duggirala, Ravi K.; Heber, Albert J.

    2013-02-01

    Odor emission from swine housing is influenced by the herd characteristics and building environment. The following three specific factors were identified as inputs to a swine house odor emission model: indoor temperature, barn ventilation rate, and pig activity. Model input parameters were determined based on tests of four, identical, 1000-head, mechanically-ventilated swine finishing houses. Each building had two sidewall curtains, a curtain on the west end wall, five exhaust fans on the east end wall, four pit ventilation fans, and long-term manure storage beneath a fully slatted floor. Odor concentrations of 112 odor samples were determined using dynamic forced-choice olfactometry with four to six trained panelists. The emission model showed that the standard live mass specific odor emission factor was 48 OU s-1 per 500 kg live mass or animal unit (AU), and it corresponded to an indoor temperature of T0 = 20 °C, a ventilation rate of V0 = 200 m3 h-1 (55.6 × 10-3 m3 s-1) per pig (maximum capacity for summer time), and the daily mean animal activity. The rate of odor emission from a swine finishing house can be calculated based on these parameters coupled with the number of animals, the mean live mass, and the standard live mass specific odor emission factor. Using this process-based odor emission model, the odor emission estimation and therefore the input for odor dispersion models can be improved to obtain more reliable estimates of separation distance for siting future pig farms.

  17. REVIEW OF EMISSION FACTORS AND METHODOLOGIES TO ESTIMATE AMMONIA EMISSIONS FROM ANIMAL WASTE HANDLING

    EPA Science Inventory

    The report summarizes and discusses recent available U.S. and European information on ammonia (NH3) emissions from swine farms and assesses its applicability for general use in the U.S., particularly in North Carolina. Emission rates for the houses calculated by various methods s...

  18. Particulate, carbon monoxide, and acid emission factors for residential wood burn stoves

    SciTech Connect

    Burnet, P.G.; Edmisten, N.G.; Tiegs, P.E.; Houck, J.E.; Yoder, R.A.

    1986-09-01

    Emissions from residential wood burning stoves are of increasing concern in many areas. This concern is due to the magnitude of the emissions and the toxic and chemical characteristics of the pollutants. Recent testing of standard and new technology woodstoves has provided data for developing a family of particulate and carbon monoxide emission factor curves. This testing has also provided data illustrating the acidity of woodstove emissions. The particulate and carbon monoxide curves relate the actual stove emissions to the stove size and operating parameters of burn rate, fuel loading, and fuel moisture. Curves relating stove types to the acidity of emissions have also been constructed. Test data show actual emissions vary from 3 to 50 grams per kilogram for particles and from 50 to 300 grams per kilogram for carbon monoxide. Since woodstove emissions are the largest single category of particulate emissions in many area, it is essential that these emissions be quantified specifically for geographic regions, allowing meaningful impact analysis modeling to be accomplished. Emission factors for particles and carbon monoxide are presented from several stove sizes and burn rates. The acidic nature of woodstove emissions has been clearly demonstrated. Tests indicate woodstove flue gas condensate solutions to be predominantly in the 2.8 to 4.2 pH range. Condensate solutions from conventional woodstoves exhibited the characteristic buffering capacity of carboxylic acids when titrations were performed with a strong base. The environmental impact of buffered acidic woodstove emissions is not currently well understood; however, it is possible with the data presented here to make semi-quantitative estimates of acid emission from particulate and carbon monoxide emission factors and wood use inventories.

  19. Incineration of different types of medical wastes: emission factors for gaseous emissions

    NASA Astrophysics Data System (ADS)

    Alvim-Ferraz, M. C. M.; Afonso, S. A. V.

    Previous research works showed that to protect public health, the hospital incinerators should be provided with air pollution control devices. As most hospital incinerators do not possess such equipment, efficient methodologies should be developed to evaluate the safety of incineration procedure. Emission factors (EF) can be used for an easy estimation of legal parameters. Nevertheless, the actual knowledge is yet very scarce, mainly because EF previously published do not include enough information about the incinerated waste composition, besides considering many different waste classifications. This paper reports the first EF estimated for CO, SO 2, NO x and HCl, associated to the incineration of medical waste, segregated in different types according to the classification of the Portuguese legislation. The results showed that those EF are strongly influenced by incinerated waste composition, directly affected by incinerated waste type, waste classification, segregation practice and management methodology. The correspondence between different waste classifications was analysed comparing the estimated EF with the sole results previously published for specific waste types, being observed that the correspondence is not always possible. The legal limit for pollutant concentrations could be obeyed for NO x, but concentrations were higher than the limit for CO (11-24 times), SO 2 (2-5 times), and HCl (9-200 times), confirming that air pollution control devices must be used to protect human health. The small heating value of medical wastes with compulsory incineration implied the requirement of a bigger amount of auxiliary fuel for their incineration, which affects the emitted amounts of CO, NO x and SO 2 (28, 20 and practically 100% of the respective values were related with fuel combustion). Nevertheless, the incineration of those wastes lead to the smallest amount of emitted pollutants, the emitted amount of SO 2 and NO x reducing to 93% and the emitted amount of CO

  20. Factors affecting regional per-capita carbon emissions in China based on an LMDI factor decomposition model.

    PubMed

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model-panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity.

  1. Factors Affecting Regional Per-Capita Carbon Emissions in China Based on an LMDI Factor Decomposition Model

    PubMed Central

    Dong, Feng; Long, Ruyin; Chen, Hong; Li, Xiaohui; Yang, Qingliang

    2013-01-01

    China is considered to be the main carbon producer in the world. The per-capita carbon emissions indicator is an important measure of the regional carbon emissions situation. This study used the LMDI factor decomposition model–panel co-integration test two-step method to analyze the factors that affect per-capita carbon emissions. The main results are as follows. (1) During 1997, Eastern China, Central China, and Western China ranked first, second, and third in the per-capita carbon emissions, while in 2009 the pecking order changed to Eastern China, Western China, and Central China. (2) According to the LMDI decomposition results, the key driver boosting the per-capita carbon emissions in the three economic regions of China between 1997 and 2009 was economic development, and the energy efficiency was much greater than the energy structure after considering their effect on restraining increased per-capita carbon emissions. (3) Based on the decomposition, the factors that affected per-capita carbon emissions in the panel co-integration test showed that Central China had the best energy structure elasticity in its regional per-capita carbon emissions. Thus, Central China was ranked first for energy efficiency elasticity, while Western China was ranked first for economic development elasticity. PMID:24353753

  2. Measurement of black carbon and particle number emission factors from individual heavy-duty trucks.

    PubMed

    Ban-Weiss, George A; Lunden, Melissa M; Kirchstetter, Thomas W; Harley, Robert A

    2009-03-01

    Emission factors for black carbon (BC) and particle number (PN) were measured from 226 individual heavy-duty (HD) diesel trucks driving through a 1-km-long California highway tunnel in August 2006. Emission factors were based on concurrent increases in BC, PN, and CO2 concentrations (measured at 1 Hz) that corresponded to the passage of individual HD trucks. The distributions of BC and PN emission factors from individual HD trucks are skewed, meaning that a large fraction of pollution comes from a small fraction of the in-use vehicle fleet. The highest-emitting 10% of trucks were responsible for approximately 40% of total BC and PN emissions from all HD trucks. BC emissions were log-normally distributed with a mean emission factor of 1.7 g kg(-1) and maximum values of approximately 10 g kg(-1). Corresponding values for PN emission factors were 4.7 x 10(15) and 4 x 10(16) # kg(-1). There was minimal overlap among high-emitters of these two pollutants: only 1 of the 226 HD trucks measured was found to be among the highest 10% for both BC and PN. Monte Carlo resampling of the distribution of BC emission factors observed in this study revealed that uncertainties (1sigma) in extrapolating from a random sample of n HD trucks to a population mean emission factor ranged from +/- 43% for n=10 to +/- 8% for n=300, illustrating the importance of vehicle sample sizes in emissions studies. When n=10, sample means are more likely to be biased due to misrepresentation of high-emitters. As vehicles become cleaner on average in the future, skewness of the emissions distributions will increase, and thus sample sizes needed to extrapolate reliably from a subset of vehicles to the entire in-use vehicle fleet will become more of a challenge. PMID:19350913

  3. Measurement of Black Carbon and Particle Number Emission Factors from Individual Heavy-Duty Trucks

    SciTech Connect

    Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W.; Harley, Robert A.

    2009-02-02

    Emission factors for black carbon (BC) and particle number (PN) were measured from 226 individual heavy-duty (HD) diesel-fueled trucks driving through a 1 km-long California highway tunnel in August 2006. Emission factors were based on concurrent increases in BC, PN, and CO{sub 2}B concentrations (measured at 1 Hz) that corresponded to the passage of individual HD trucks. The distributions of BC and PN emission factors from individual HD trucks are skewed, meaning that a large fraction of pollution comes from a small fraction of the in-use vehicle fleet. The highest-emitting 10% of trucks were responsible for {approx} 40% of total BC and PN emissions from all HD trucks. BC emissions were log-normally distributed with a mean emission factor of 1.7 g kg {sup -1} and maximum values of {approx} 10 g kg{sup -1}. Corresponding values for PN emission factors were 4.7 x 10{sup 15} and 4 x 10{sup 16} kg{sup -1}. There was minimal overlap among high-emitters of these two pollutants: only 1 of the 226 HD trucks measured was found to be among the highest 10% for both BC and PN. Monte Carlo resampling of the distribution of BC emission factors observed in this study revealed that uncertainties (1{sigma}) in extrapolating from a random sample of n HD trucks to a population mean emission factor ranged from {+-} 43% for n = 10 to {+-} 8% for n = 300, illustrating the importance of sufficiently large vehicle sample sizes in emissions studies. Studies with low sample sizes are also more easily biased due to misrepresentation of high-emitters. As vehicles become cleaner on average in future years, skewness of the emissions distributions will increase, and thus sample sizes needed to extrapolate reliably from a subset of vehicles to the entire in-use vehicle fleet are expected to become more of a challenge.

  4. Estimation of the methane emission factor for the Italian Mediterranean buffalo.

    PubMed

    Cóndor, R D; Valli, L; De Rosa, G; Di Francia, A; De Lauretis, R

    2008-08-01

    In order to contribute to the improvement of the national greenhouse gas emission inventory, this work aimed at estimating a country-specific enteric methane (CH4) emission factor for the Italian Mediterranean buffalo. For this purpose, national agriculture statistics, and information on animal production and farming conditions were analysed, and the emission factor was estimated using the Tier 2 model of the Intergovernmental Panel on Climate Change. Country-specific CH4 emission factors for buffalo cows (630 kg body weight, BW) and other buffalo (313 kg BW) categories were estimated for the period 1990-2004. In 2004, the estimated enteric CH4 emission factor for the buffalo cows was 73 kg/head per year, whereas that for other buffalo categories it was 56 kg/head per year. Research in order to determine specific CH4 conversion rates at the predominant production system is suggested.

  5. Development and selection of ammonia emission factors. Final report, February-August 1994

    SciTech Connect

    Battye, R.; Battye, W.; Overcash, C.; Fudge, S.

    1994-08-01

    This report compiles recent literature on ammonia (NH3) emission factors for application in the United States. Most of the recent research supports acid deposition studies in the European community (specifically, the Netherlands, Great Britain, and Scandinavia) but some research has been conducted in Australia. The majority of NH3 emissions in current inventories, up to 90% or more of anthropogenic emissions, originates from livestock wastes with fertilizer applications providing a significant proportion. Some inventories exclude industrial emissions entirely because they are insignificant relative to agricultural sources. Global climate change research indicates that undisturbed soils and biomass burning may also have significant emissions, up to half of the global NH3 budget.

  6. Source Energy and Emission Factors for Energy Use in Buildings (Revised)

    SciTech Connect

    Deru, M.; Torcellini, P.

    2007-06-01

    This document supports the other measurement procedures and all building energy-monitoring projects by providing methods to calculate the source energy and emissions from the energy measured at the building. Energy and emission factors typically account for the conversion inefficiencies at the power plant and the transmission and distribution losses from the power plant to the building. The energy and emission factors provided here also include the precombustion effects, which are the energy and emissions associated with extracting, processing, and delivering the primary fuels to the point of conversion in the electrical power plants or directly in the buildings.

  7. Quantification of variability and uncertainty in lawn and garden equipment NOx and total hydrocarbon emission factors.

    PubMed

    Frey, H Christopher; Bammi, Sachin

    2002-04-01

    Variability refers to real differences in emissions among multiple emission sources at any given time or over time for any individual emission source. Variability in emissions can be attributed to variation in fuel or feedstock composition, ambient temperature, design, maintenance, or operation. Uncertainty refers to lack of knowledge regarding the true value of emissions. Sources of uncertainty include small sample sizes, bias or imprecision in measurements, nonrepresentativeness, or lack of data. Quantitative methods for characterizing both variability and uncertainty are demonstrated and applied to case studies of emission factors for lawn and garden (L&G) equipment engines. Variability was quantified using empirical and parametric distributions. Bootstrap simulation was used to characterize confidence intervals for the fitted distributions. The 95% confidence intervals for the mean grams per brake horsepower/hour (g/hp-hr) emission factors for two-stroke engine total hydrocarbon (THC) and NOx emissions were from -30 to +41% and from -45 to +75%, respectively. The confidence intervals for four-stroke engines were from -33 to +46% for THCs and from -27 to +35% for NOx. These quantitative measures of uncertainty convey information regarding the quality of the emission factors and serve as a basis for calculation of uncertainty in emission inventories (EIs).

  8. SENSITIVITY ANALYSIS AND EVALUATION OF MICROFACO: A MICROSCALE MOTOR VEHICLE EMISSION FACTOR MODEL FOR CO EMISSIONS

    EPA Science Inventory

    The United States Environmental Protection Agency's National Exposure Research Laboratory has initiated a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source t...

  9. A Portable Emissions Measurement System (PEMS) study of NOx and primary NO2 emissions from Euro 6 diesel passenger cars and comparison with COPERT emission factors

    NASA Astrophysics Data System (ADS)

    O'Driscoll, Rosalind; ApSimon, Helen M.; Oxley, Tim; Molden, Nick; Stettler, Marc E. J.; Thiyagarajah, Aravinth

    2016-11-01

    Real world emissions of oxides of nitrogen (NOx) often greatly exceed those achieved in the laboratory based type approval process. In this paper the real world emissions from a substantial sample of the latest Euro 6 diesel passenger cars are presented with a focus on NOx and primary NO2. Portable Emissions Measurement System (PEMS) data is analysed from 39 Euro 6 diesel passenger cars over a test route comprised of urban and motorway sections. The sample includes vehicles installed with exhaust gas recirculation (EGR), lean NOx traps (LNT), or selective catalytic reduction (SCR). The results show wide variability in NOx emissions from 1 to 22 times the type approval limit. The average NOx emission, 0.36 (sd. 0.36) g km-1, is 4.5 times the Euro 6 limit. The average fraction primary NO2 (fNO2) is 44 (sd. 20) %. Higher emissions during the urban section of the route are attributed to an increased number of acceleration events. Comparisons between PEMS measurements and COPERT speed dependent emissions factors show PEMS measurements to be on average 1.6 times higher than COPERT estimates for NOx and 2.5 times for NO2. However, by removing the 5 most polluting vehicles average emissions were reduced considerably.

  10. Determination of fleet hourly emission and on-road vehicle emission factor using integrated monitoring and modeling approach

    NASA Astrophysics Data System (ADS)

    Kim Oanh, N. T.; Martel, M.; Pongkiatkul, P.; Berkowicz, R.

    Roadside air quality and vehicle emission are important and challenging issues in urban air quality management which need to be adequately characterized. This study involves designing a monitoring program that produces suitable data to determine the on-road hourly fleet emission and emission factors of individual vehicles in a street canyon. Simultaneous hourly monitoring of roadside gaseous pollutants (both windward and leeward sides), traffic volume and speed, and wind in a busy street of Bangkok was conducted in the rainy season when traffic emission was predominant in the city. Higher pollutant concentrations often occurred at midday (11:00 to 14:00h) when higher traffic density (3700-3800vehicles h - 1, weekdays) was observed. The levels of toluene and xylenes found in this study are higher than the roadside levels reported in other Asian cities. Hourly maximum concentrations reached 258ppb for toluene, 51ppb for m, p-xylenes, 15ppb for o-xylene, 526ppb for NO x, and 10.5ppm for CO. Hourly monitoring data during the periods when the street canyon effects were pronounced were selected for determination of the fleet hourly emission and vehicle emission factors by back calculation using a street canyon model (Operational Street Pollution Model). The average fleet hourly emission at daytime of NO x (6.2kg km - 1 h - 1), CO (54kg km - 1 h - 1), toluene (2.1kg km - 1 h - 1), m, p-xylenes (0.73kg km - 1 h - 1) and o-xylene (0.27kg km - 1 h - 1) did not vary much. However, the emission rates were substantially reduced at nighttime following the traffic pattern. The obtained pollutant emission factors varied within each group of vehicles with the average values agreed reasonably with the chassis dynamometer results for NO x but somewhat higher for CO and TX. The model estimated results are, however, considered to better represent the real driving conditions in the street at the average vehicle travel speed of around 20km h - 1. A statistical sampling design is proposed

  11. Emissions factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

    NASA Astrophysics Data System (ADS)

    Zhang, F.; Chen, Y.; Tian, C.; Li, J.; Zhang, G.; Matthias, V.

    2015-09-01

    Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbor districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel engine power offshore vessels in China were measured in this study. Concentrations, fuel-based and power-based emissions factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emissions factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low engine power vessel than for the two higher engine power vessels. Fuel-based average emissions factors for all pollutants except sulfur dioxide in the low engine power engineering vessel were significantly higher than that of the previous studies, while for the two higher engine power vessels, the fuel-based average emissions factors for all pollutants were comparable to the results of the previous studies. The fuel-based average emissions factor for nitrogen oxides for the small engine power vessel was more than twice the International Maritime Organization standard, while those for the other two vessels were below the standard. Emissions factors for all three vessels were significantly different during different operating modes. Organic carbon and elemental carbon were the main components of particulate matter, while water-soluble ions and elements were present in trace amounts. Best-fit engine speeds

  12. The development of PM emission factor for small incinerators and boilers.

    PubMed

    Yoo, J I; Kim, K H; Jang, H N; Seo, Y C; Seok, K S; Hong, J H; Jang, M

    2002-12-01

    This study is intended to develop the emission factors of particulate matter such as TPM (total particulate matter), PM-10 (particulate matter less than 10 micrometers in aerodynamic diameter), PM-2.5 (particulate matter less than 2.5 micrometers in aerodynamic diameters) and several types of inorganic matter from small-size incinerators (less than 250 kg hr(-1) capacity) and boilers (less than 5 ton hr(-1) capacity a s steam generation) for various compositions of wastes and fuels, respectively.The emission factors for particulate matter from boilers were similar to the US EPA data. However, the emission factors from small incinerators were higher than the emission factors developed in other countries because the emission characteristics were different, especially with respect to the combustor's capacity. Emission factors for heavy metals such as cadmium, manganese, chromium, magnesium, lead, zinc, and copper were also investigated. The emission factors in this study were higher than those in other studies. Particle size distribution of PM-10 and the ratio of submicron PM to TPM were observed and a mode (peak) of submicron size particles together with a higher concentration of them was found, which could be explained by the formation of fines from vaporized metals wastes. PMID:12523513

  13. On-Road Measurement of Exhaust Emission Factors for Individual Diesel Trucks

    NASA Astrophysics Data System (ADS)

    Dallmann, T. R.; DeMartini, S.; Harley, R. A.; Kirchstetter, T. W.; Wood, E. C.; Onasch, T. B.; Herndon, S. C.

    2011-12-01

    Diesel trucks are an important source of primary fine particulate matter (PM2.5) that includes black carbon (BC) as a major component. More stringent exhaust emission standards for new engines, effective starting in 2007, considerably reduce allowable emissions and have led to use of after-treatment control devices such as diesel particle filters. The state of California is also implementing programs to accelerate replacement or retrofit of older trucks. In light of these changes, measurements of emissions from in-use heavy-duty diesel trucks are timely and needed to understand the impact of new control technologies on emissions. PM2.5, BC mass, particle light absorption, and particle light extinction emission factors for hundreds of individual diesel trucks were measured in this study. Emissions were measured in July 2010 from trucks driving through the Caldecott tunnel in the San Francisco Bay area. Gas-phase emissions including nitric oxide, nitrogen dioxide, carbon monoxide, and carbon dioxide (CO2) were also measured. Pollutants were measured using air sampling inlets located directly above the vertical exhaust stacks of heavy-duty trucks driving by on the roadway below. All of these measurements were made using fast time response (1 Hz) sensors. Particle optical properties were simultaneously characterized with direct measurements of absorption (babs) and extinction (bext) coefficients. Emission factors for individual trucks were calculated using a carbon balance method in which emissions of PM2.5, BC, babs, and bext in each exhaust plume were normalized to emissions of CO2. Emission factor distributions and fleet-average values are quantified. Absorption and extinction emission factors are used to calculate the aerosol single scattering albedo and BC mass absorption efficiency for individual truck exhaust plumes.

  14. Emission factors from biomass burning in three types of appliances: fireplace, woodstove and pellet stove

    NASA Astrophysics Data System (ADS)

    Duarte, Márcio; Vicente, Estela; Calvo, Ana; Nunes, Teresa; Tarelho, Luis; Alves, Célia

    2014-05-01

    In the last years, the importance of biomass fuels has increased mainly for two reasons. One of them is the effort to control the emissions of greenhouse gases, and on the other hand, the increasing costs associated with fossil fuels. Besides that, biomass burning is now recognised as one of the major sources contributing to high concentrations of particulate matter, especially during winter time. Southern European countries have a lack of information regarding emission profiles from biomass burning. Because of that, in most source apportionment studies, the information used comes from northern and alpine countries, whose combustion appliances, fuels and habits are different from those in Mediterranean countries. Due to this lack of information, series of tests using different types of equipment, as well as fuels, were carried out in order to obtain emission profiles and emission factors that correspond to the reality in southern European countries. Tests involved three types of biomass appliances used in Portugal, a fireplace, a woodstove and a modern pellet stove. Emission factors (mg.kg-1 fuel, dry basis) for CO, THC and PM10 were obtained. CO emission factors ranged from 38, for pine on the woodstove, to 84 for eucalyptus in the fireplace. THC emissions were between 4 and 24, for pine in the woodstove and eucalyptus in the fireplace, respectively. PM10 emission factors were in the range from 3.99, for pine in the woodstove, to 17.3 for eucalyptus in the fireplace. On average, the emission factors obtained for the fireplace are 1.5 (CO) to 4 (THC) times higher than those of the woodstove. The fireplace has emission factors for CO, THC and PM10 10, 35 and 32 times, respectively, higher than the pellet stove.

  15. Seasonal variations in terpene emission factors of dominant species in four ecosystems in NE Spain

    NASA Astrophysics Data System (ADS)

    Llusia, Joan; Peñuelas, Josep; Guenther, Alex; Rapparini, Francesca

    2013-05-01

    We studied the daily patterns in the rates of foliar terpene emissions by four typical species from the Mediterranean region in two days of early spring and two days of summer in 4 localities of increasing biomass cover in Northern Spain. The species studied were Thymelaea tinctoria (in Monegros), Quercus coccifera (in Garraf), Quercus ilex (in Prades) and Fagus sylvatica (in Montseny). Of the total 43 VOCs detected, 23 were monoterpenes, 5 sesquiterpenes and 15 were not terpenes. Sesquiterpenes were the main terpenes emitted from T. tinctoria. Total VOC emission rates were on average about 15 times higher in summer than in early spring. The maximum rates of emission were recorded around midday. Emissions nearly stopped in the dark. No significant differences were found for nocturnal total terpene emission rates between places and seasons. The seasonal variations in the rate of terpene emissions and in their chemical composition can be explained mainly by dramatic changes in emission factors (emission capacity) associated in some cases, such as for beech trees, with very different foliar ontogenical characteristics between spring and summer. The results show that temperature and light-standardised emission rates were on average about 15 times higher in summer than in early spring, which, corroborating other works, calls to attention when applying the same emission factor in modelling throughout the different seasons of the year.

  16. A comprehensive assessment of PM emissions from paved roads: real-world Emission Factors and intense street cleaning trials.

    PubMed

    Amato, F; Nava, S; Lucarelli, F; Querol, X; Alastuey, A; Baldasano, J M; Pandolfi, M

    2010-09-15

    Compliance with air quality standards requires control of source emissions: fine exhaust particles are already subject to regulation but vehicle fleets increase whilst the non-exhaust emissions are totally uncontrolled. Emission inventories are scarce despite their suitability for researchers and regulating agencies for managing air quality and PM reduction measures. Only few countries in Europe proposed street cleaning as a possible control measure, but its effectiveness is still far to be determined. This study offers first estimates of Real-world Emission Factors for PM(10) and brake-wear elements and the effect on PM(10) concentrations induced by intense street cleaning trials. A straightforward campaign was carried out in the city of Barcelona with hourly elemental composition of fine and coarse PM to detect any short-term effect of street cleaning on specific tracers of non-exhaust emissions. Samples were analyzed by Particle Induced X-Ray Emission. Real-world Emission Factor for PM(10) averaged for the local fleet resulted to be 97 mg veh(-1) km(-1). When compared to other European studies, our EF resulted higher than what found in UK, Germany, Switzerland and Austria but lower than Scandinavian countries. For brake-related elements, total EFs were estimated, accounting for the sum of direct and resuspension emissions, in 7400, 486, 106 and 86 microg veh(-1) km(-1), respectively for Fe, Cu, Sn and Sb. In PM(2.5)Fe and Cu emission factors were respectively 4884 and 306 microg veh(-1) km(-1). Intense street cleaning trials evidenced a PM(10) reduction at kerbside of 3 microg m(-3) (mean daily levels of 54 microg m(-3)), with respect to reference stations. It is important to remark that such benefit could only be detected in small time-integration periods (12:00-18:00) since in daily values this benefit was not noticed. Hourly PM elemental monitoring allowed the identification of mineral and brake-related metallic particles as those responsible of the PM(10

  17. 75 FR 26904 - Mandatory Reporting of Greenhouse Gases: Notice of Data Availability; Default Emission Factors...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-13

    ... of Greenhouse Gases: Additional Sources of Fluorinated GHGs (75 FR 18652) which included proposed... factor, EPA proposed a range of values differentiated by production technology generation (i.e., wafer... factors as well as the underlying data that was used to develop the draft emission factors available...

  18. On-road emission factor distributions of individual diesel vehicles in and around Beijing, China

    NASA Astrophysics Data System (ADS)

    Wang, Xing; Westerdahl, Dane; Wu, Ye; Pan, Xiaochuan; Zhang, K. Max

    2011-01-01

    This paper reports findings of a recent field study that characterized the on-road emissions of individual diesel vehicles in and around Beijing, China during November and December of 2009. We successfully sampled 230 individual trucks on 4 major expressways around the city as well as 57 individual buses in the city using refined mobile chasing techniques and fast response instruments. Emission factors (EF) for carbon monoxide (CO), black carbon (BC) and particulate matter with diameters less than 0.5 μm (PM 0.5) are derived from the measurements, which are consistent with the results from laboratory dynamometer tests. The PM 0.5 number emission factor distributions demonstrate consistent bimodal modes with peaks around 10 nm and 80 nm, while the mass emission factor distributions demonstrate a unimodal maximum around 110 nm for a majority of the trucks. The BC emissions are shown to be highly correlated with the mass emission of particles with 100-250 nm diameters, which are in good agreement with the results from previous studies. A number of important policy implications are discussed based on the results from this study. First, we identified "heavy emitters" in the on-road fleet we encountered, finding that 5% of diesel trucks in this sample are responsible for 50% of total BC emissions, and 20% of the trucks are responsible for 50% CO and PM 0.5 number emissions, 60% PM 0.5 mass emissions and over 70% of BC emissions. This suggests that emissions control programs should include identifying and removing heavy emitters from the road or improving their emissions. Second, the BC and PM 0.5 number emission factors of trucks registered in regions outside Beijing are significantly higher than those of Beijing-registered trucks, suggesting that improving engine and fuel standards in Beijing alone is not sufficient in reducing the traffic-related air pollution in Beijing. Third, the significantly lower emissions from Euro IV and CNG buses compared to the Euro II and

  19. Mutagenicity and Pollutant Emission Factors of Solid-Fuel Cookstoves: Comparison with Other Combustion Sources

    PubMed Central

    Mutlu, Esra; Warren, Sarah H.; Ebersviller, Seth M.; Kooter, Ingeborg M.; Schmid, Judith E.; Dye, Janice A.; Linak, William P.; Gilmour, M. Ian; Jetter, James J.; Higuchi, Mark; DeMarini, David M.

    2016-01-01

    Background: Emissions from solid fuels used for cooking cause ~4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects. Objective: We evaluated two categories of solid-fuel cookstoves for eight pollutant and four mutagenicity emission factors, correlated the mutagenicity emission factors, and compared them to those of other combustion emissions. Methods: We burned red oak in a 3-stone fire (TSF), a natural-draft stove (NDS), and a forced-draft stove (FDS), and we combusted propane as a liquified petroleum gas control fuel. We determined emission factors based on useful energy (megajoules delivered, MJd) for carbon monoxide, nitrogen oxides (NOx), black carbon, methane, total hydrocarbons, 32 polycyclic aromatic hydrocarbons, PM2.5, levoglucosan (a wood-smoke marker), and mutagenicity in Salmonella. Results: With the exception of NOx, the emission factors per MJd were highly correlated (r ≥ 0.97); the correlation for NOx with the other emission factors was 0.58–0.76. Excluding NOx, the NDS and FDS reduced the emission factors an average of 68 and 92%, respectively, relative to the TSF. Nevertheless, the mutagenicity emission factor based on fuel energy used (MJthermal) for the most efficient stove (FDS) was between those of a large diesel bus engine and a small diesel generator. Conclusions: Both mutagenicity and pollutant emission factors may be informative for characterizing cookstove performance. However, mutagenicity emission factors may be especially useful for characterizing potential health effects and should be evaluated in relation to health outcomes in future research. An FDS operated as intended by the manufacturer is safer than a TSF, but without adequate ventilation, it will still result in poor indoor air quality. Citation: Mutlu E, Warren SH, Ebersviller SM, Kooter IM, Schmid JE, Dye JA, Linak WP, Gilmour MI, Jetter

  20. Toxic volatile organic compounds in environmental tobacco smoke: Emission factors for modeling exposures of California populations

    SciTech Connect

    Daisey, J.M.; Mahanama, K.R.R.; Hodgson, A.T.

    1994-10-01

    The primary objective of this study was to measure emission factors for selected toxic air contaminants in environmental tobacco smoke (ETS) using a room-sized environmental chamber. The emissions of 23 volatile organic compounds (VOCs), including, 1,3-butadiene, three aldehydes and two vapor-phase N-nitrosamines were determined for six commercial brands of cigarettes and reference cigarette 1R4F. The commercial brands were selected to represent 62.5% of the cigarettes smoked in California. For each brand, three cigarettes were machine smoked in the chamber. The experiments were conducted over four hours to investigate the effects of aging. Emission factors of the target compounds were also determined for sidestream smoke (SS). For almost all target compounds, the ETS emission factors were significantly higher than the corresponding SS values probably due to less favorable combustion conditions and wall losses in the SS apparatus. Where valid comparisons could be made, the ETS emission factors were generally in good agreement with the literature. Therefore, the ETS emission factors, rather than the SS values, are recommended for use in models to estimate population exposures from this source. The variabilities in the emission factors ({mu}g/cigarette) of the selected toxic air contaminants among brands, expressed as coefficients of variation, were 16 to 29%. Therefore, emissions among brands were Generally similar. Differences among brands were related to the smoked lengths of the cigarettes and the masses of consumed tobacco. Mentholation and whether a cigarette was classified as light or regular did not significantly affect emissions. Aging was determined not to be a significant factor for the target compounds. There were, however, deposition losses of the less volatile compounds to chamber surfaces.

  1. Real-time particle monitor calibration factors and PM2.5 emission factors for multiple indoor sources.

    PubMed

    Dacunto, Philip J; Cheng, Kai-Chung; Acevedo-Bolton, Viviana; Jiang, Ruo-Ting; Klepeis, Neil E; Repace, James L; Ott, Wayne R; Hildemann, Lynn M

    2013-08-01

    Indoor sources can greatly contribute to personal exposure to particulate matter less than 2.5 μm in diameter (PM2.5). To accurately assess PM2.5 mass emission factors and concentrations, real-time particle monitors must be calibrated for individual sources. Sixty-six experiments were conducted with a common, real-time laser photometer (TSI SidePak™ Model AM510 Personal Aerosol Monitor) and a filter-based PM2.5 gravimetric sampler to quantify the monitor calibration factors (CFs), and to estimate emission factors for common indoor sources including cigarettes, incense, cooking, candles, and fireplaces. Calibration factors for these indoor sources were all significantly less than the factory-set CF of 1.0, ranging from 0.32 (cigarette smoke) to 0.70 (hamburger). Stick incense had a CF of 0.35, while fireplace emissions ranged from 0.44-0.47. Cooking source CFs ranged from 0.41 (fried bacon) to 0.65-0.70 (fried pork chops, salmon, and hamburger). The CFs of combined sources (e.g., cooking and cigarette emissions mixed) were linear combinations of the CFs of the component sources. The highest PM2.5 emission factors per time period were from burned foods and fireplaces (15-16 mg min(-1)), and the lowest from cooking foods such as pizza and ground beef (0.1-0.2 mg min(-1)). PMID:23784066

  2. A summary of ammonia emission factors and quality criteria for commercial poultry production in North America

    NASA Astrophysics Data System (ADS)

    Wood, David; Cowherd, Savannah; Van Heyst, Bill

    2015-08-01

    Efforts to quantify emissions of ammonia to the atmosphere from poultry housing in North America have been underway for the past two decades. In order to accurately estimate emissions from facilities in each poultry sector, emission factors used to derive the average must be of sufficiently high quality. However, it has become evident that current methods are inadequate and emission factors do not accurately reflect North American poultry production. Using an initial screening, based on measurement methods for ammonia and ventilation rates as well as study duration, a collection of studies have been identified that report the highest quality emission factors currently available. Each study was rated for data quality and then an average emission factor was developed for each sector of poultry production and rated based its ability to represent that sector. The laying hen sector, using deep pit manure storage, received a C (average) emission factor quality rating, which is the highest of all the poultry sectors evaluated. Laying hen with manure belts, broiler chicken, and turkey sectors received quality ratings considered to be below average or poor. This study highlights the need for additional research that needs to be conducted in order to accurately quantify ammonia releases from housing in most poultry sectors in North America.

  3. Source apportionment of stack emissions from research and development facilities using positive matrix factorization

    NASA Astrophysics Data System (ADS)

    Ballinger, Marcel Y.; Larson, Timothy V.

    2014-12-01

    Research and development (R&D) facility emissions are difficult to characterize due to their variable processes, changing nature of research, and large number of chemicals. Positive matrix factorization (PMF) was applied to volatile organic compound (VOC) concentrations measured in the main exhaust stacks of four different R&D buildings to identify the number and composition of major contributing sources. PMF identified between 9 and 11 source-related factors contributing to stack emissions, depending on the building. Similar factors between buildings were major contributors to trichloroethylene (TCE), acetone, and ethanol emissions; other factors had similar profiles for two or more buildings but not all four. At least one factor for each building was identified that contained a broad mix of many species and constraints were used in PMF to modify the factors to resemble more closely the off-shift concentration profiles. PMF accepted the constraints with little decrease in model fit.

  4. Evaluation of life-cycle air emission factors of freight transportation.

    PubMed

    Facanha, Cristiano; Horvath, Arpad

    2007-10-15

    Life-cycle air emission factors associated with road, rail, and air transportation of freight in the United States are analyzed. All life-cycle phases of vehicles, infrastructure, and fuels are accounted for in a hybrid life-cycle assessment (LCA). It includes not only fuel combustion, but also emissions from vehicle manufacturing, maintenance, and end of life, infrastructure construction, operation, maintenance, and end of life, and petroleum exploration, refining, and fuel distribution. Results indicate that total life-cycle emissions of freight transportation modes are underestimated if only tailpipe emissions are accounted for. In the case of CO2 and NOx, tailpipe emissions underestimate total emissions by up to 38%, depending on the mode. Total life-cycle emissions of CO and SO2 are up to seven times higher than tailpipe emissions. Sensitivity analysis considers the effects of vehicle type, geography, and mode efficiency on the final results. Policy implications of this analysis are also discussed. For example, while it is widely assumed that currently proposed regulations will result in substantial reductions in emissions, we find that this is true for NOx, emissions, because fuel combustion is the main cause, and to a lesser extent for SO2, but not for PM10 emissions, which are significantly affected by the other life-cycle phases.

  5. FIELD MEASUREMENT OF GREENHOUSE GAS EMISSION RATES AND DEVELOPMENT OF EMISSION FACTORS FOR WASTEWATER TREATMENT

    EPA Science Inventory

    The report gives results of field testing to develop more reliable green house gas (GHG) emission estimates for Wastewater treatment (WWT) lagoons. (NOTE: Estimates are available for the amount of methane (CH4) emitted from certain types of waste facilities, but there is not adeq...

  6. 78 FR 14533 - Official Release of EMFAC2011 Motor Vehicle Emission Factor Model for Use in the State of California

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-06

    ..., calculates air pollution emissions factors for passenger cars, trucks, motorcycles, motor homes and buses... AGENCY Official Release of EMFAC2011 Motor Vehicle Emission Factor Model for Use in the State of... EMission FACtor) for use in state implementation plan (SIP) development and transportation conformity...

  7. Development of cotton gin PM10 emission factors for EPA’s AP-42-DUPLICATE DO NOT USE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Compilation of Air Pollution Emission Factors (AP-42) emission factors are assigned ratings, from A (Excellent) to E (Poor), based on the quality of data used to develop them. All current PM10 cotton gin emission factors received quality ratings of D or lower. In an effort to improve these ratin...

  8. 40 CFR Table W - 5 of Subpart W-Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Factors for Liquefied Natural Gas (LNG) Storage W Table W Protection of Environment ENVIRONMENTAL... Natural Gas Systems Definitions. Pt. 98, Subpt. W, Table W-5 Table W-5 of Subpart W—Default Methane Emission Factors for Liquefied Natural Gas (LNG) Storage LNG storage Emission factor...

  9. Characterization factors for water consumption and greenhouse gas emissions based on freshwater fish species extinction.

    PubMed

    Hanafiah, Marlia M; Xenopoulos, Marguerite A; Pfister, Stephan; Leuven, Rob S E W; Huijbregts, Mark A J

    2011-06-15

    Human-induced changes in water consumption and global warming are likely to reduce the species richness of freshwater ecosystems. So far, these impacts have not been addressed in the context of life cycle assessment (LCA). Here, we derived characterization factors for water consumption and global warming based on freshwater fish species loss. Calculation of characterization factors for potential freshwater fish losses from water consumption were estimated using a generic species-river discharge curve for 214 global river basins. We also derived characterization factors for potential freshwater fish species losses per unit of greenhouse gas emission. Based on five global climate scenarios, characterization factors for 63 greenhouse gas emissions were calculated. Depending on the river considered, characterization factors for water consumption can differ up to 3 orders of magnitude. Characterization factors for greenhouse gas emissions can vary up to 5 orders of magnitude, depending on the atmospheric residence time and radiative forcing efficiency of greenhouse gas emissions. An emission of 1 ton of CO₂ is expected to cause the same impact on potential fish species disappearance as the water consumption of 10-1000 m³, depending on the river basin considered. Our results make it possible to compare the impact of water consumption with greenhouse gas emissions.

  10. High NO2/NOx emissions downstream of the catalytic diesel particulate filter: An influencing factor study.

    PubMed

    He, Chao; Li, Jiaqiang; Ma, Zhilei; Tan, Jianwei; Zhao, Longqing

    2015-09-01

    Diesel vehicles are responsible for most of the traffic-related nitrogen oxide (NOx) emissions, including nitric oxide (NO) and nitrogen dioxide (NO2). The use of after-treatment devices increases the risk of high NO2/NOx emissions from diesel engines. In order to investigate the factors influencing NO2/NOx emissions, an emission experiment was carried out on a high pressure common-rail, turbocharged diesel engine with a catalytic diesel particulate filter (CDPF). NO2 was measured by a non-dispersive ultraviolet analyzer with raw exhaust sampling. The experimental results show that the NO2/NOx ratios downstream of the CDPF range around 20%-83%, which are significantly higher than those upstream of the CDPF. The exhaust temperature is a decisive factor influencing the NO2/NOx emissions. The maximum NO2/NOx emission appears at the exhaust temperature of 350°C. The space velocity, engine-out PM/NOx ratio (mass based) and CO conversion ratio are secondary factors. At a constant exhaust temperature, the NO2/NOx emissions decreased with increasing space velocity and engine-out PM/NOx ratio. When the CO conversion ratios range from 80% to 90%, the NO2/NOx emissions remain at a high level.

  11. Provincial variation of carbon emissions from bituminous coal: Influence of inertinite and other factors

    USGS Publications Warehouse

    Quick, J.C.; Brill, T.

    2002-01-01

    We observe a 1.3 kg C/net GJ variation of carbon emissions due to inertinite abundance in some commercially available bituminous coal. An additional 0.9 kg C/net GJ variation of carbon emissions is expected due to the extent of coalification through the bituminous rank stages. Each percentage of sulfur in bituminous coal reduces carbon emissions by about 0.08 kg C/net GJ. Other factors, such as mineral content, liptinite abundance and individual macerals, also influence carbon emissions, but their quantitative effect is less certain. The large range of carbon emissions within the bituminous rank class suggests that rank- specific carbon emission factors are provincial rather than global. Although carbon emission factors that better account for this provincial variation might be calculated, we show that the data used for this calculation may vary according to the methods used to sample and analyze coal. Provincial variation of carbon emissions and the use of different coal sampling and analytical methods complicate the verification of national greenhouse gas inventories. Published by Elsevier Science B.V.

  12. High NO2/NOx emissions downstream of the catalytic diesel particulate filter: An influencing factor study.

    PubMed

    He, Chao; Li, Jiaqiang; Ma, Zhilei; Tan, Jianwei; Zhao, Longqing

    2015-09-01

    Diesel vehicles are responsible for most of the traffic-related nitrogen oxide (NOx) emissions, including nitric oxide (NO) and nitrogen dioxide (NO2). The use of after-treatment devices increases the risk of high NO2/NOx emissions from diesel engines. In order to investigate the factors influencing NO2/NOx emissions, an emission experiment was carried out on a high pressure common-rail, turbocharged diesel engine with a catalytic diesel particulate filter (CDPF). NO2 was measured by a non-dispersive ultraviolet analyzer with raw exhaust sampling. The experimental results show that the NO2/NOx ratios downstream of the CDPF range around 20%-83%, which are significantly higher than those upstream of the CDPF. The exhaust temperature is a decisive factor influencing the NO2/NOx emissions. The maximum NO2/NOx emission appears at the exhaust temperature of 350°C. The space velocity, engine-out PM/NOx ratio (mass based) and CO conversion ratio are secondary factors. At a constant exhaust temperature, the NO2/NOx emissions decreased with increasing space velocity and engine-out PM/NOx ratio. When the CO conversion ratios range from 80% to 90%, the NO2/NOx emissions remain at a high level. PMID:26354692

  13. Variation Trend and Driving Factors of Greenhouse Gas Emissions from Chinese Magnesium Production.

    PubMed

    Gao, Feng; Liu, Yu; Nie, Zuo-Ren; Gong, Xianzheng; Wang, Zhihong

    2015-11-01

    As the largest magnesium producer in the world, China is facing a great challenge of greenhouse gas (GHG) emissions reduction. In this paper, the variation trend and driving factors of GHG emissions from Chinese magnesium production were evaluated and the measures of technology and policy for effectively mitigating GHG emissions were provided. First, the energy-related and process-oriented GHG inventory is compiled for magnesium production in China. Then, the driving forces for the changes of the energy-related emission were analyzed by the method of Logarithmic Mean Divisia Index (LMDI) decomposition. Results demonstrated that Chinese magnesium output from 2003 to 2013 increased by 125%, whereas GHG emissions only increased by 16%. The emissions caused by the fuels consumption decline most significantly (from 28.4 to 6.6 t CO2eq/t Mg) among all the emission sources. The energy intensity and the energy structure were the main offsetting factors for the increase of GHG emissions, while the scale of production and the international market demand were the main contributors for the total increase. Considering the improvement of technology application and more stringent policy measures, the annual GHG emissions from Chinese primary magnesium production will be controlled within 22 million tons by 2020.

  14. An instantaneous approach for determining the infrared emissivity of swine surface and the influencing factors.

    PubMed

    Zhang, Kun; Jiao, Leizi; Zhao, Xiande; Dong, Daming

    2016-04-01

    Infrared thermal imaging technology has been widely employed in temperature measurements of human and animals and its accuracy relies on the determination process of the emissivity of the target to a large extent. However, common used methods were unable to determine the emissivity of the surface of living animals and thus lower the accuracy. In this paper, we suggested a new approach to acquire the infrared emissivity of living swine in real time. In the approach, the surface temperature of swine and reference body were measured to compute the emissivity and the measurement process was completed in a non-contact and non-invasive manner. We changed the surface reflection energy of animals and reference body by changing the ambient radiant energy and obtain the surface emissivity in real time without confirming the actual temperature of animal surface. In this way, the infrared emissivity of the animal surface can be determined instantaneously and without knowing the real temperature. Both swine specimen and a living swine were used in this study. Using this method, we measured the emissivity of different body sites of the swine. The results showed that the emissivity values at different body sites show the significant differences. The emissivity values at trotter and eye were respectively 0.895 and 0.930 and the emissivity on swine surface varied from 0.945 to 0.978. More important, the distribution of the infrared emissivity on a living swine was explored and the detailed differences of the emissivity on a swine surface can be cleanly seen. Furthermore, we studied the influencing factors on the emissivity of animal surface, through measuring the emissivity distribution on swine surface when pig specimens were sprayed with water on the surface or heated using this method. This study is of great significance for the accurate measurement of swine surface temperature.

  15. Emission Factors of Greenhouse Gases and Particulates from Australian Savanna Fires

    NASA Astrophysics Data System (ADS)

    Desservettaz, Maximilien; Paton-Walsh, Clare; Griffith, David; Kettlewell, Graham; Wilson, Stephen; Keywood, Melita; Van der Schoot, Marcel; Seleck, Paul; Ward, Jason; Harwell, James; Reisen, Fabienne; Lawson, Sarah; Ristovski, Zoran; Mallet, Marc; Miljevic, Brenka; Milic, Andjelija; Atkinson, Brad

    2016-04-01

    In June 2014 a measurement campaign took place at the Australian Tropical Atmospheric Research Station (ATARS), in the Northern Territory, Australia, during the early dry season. The campaign was focused on understanding biomass burning emissions from savanna fires. In order to achieve this, a suite of aerosol, reactive and trace gases instruments were deployed. Seven smoke events were extracted from the 4 weeks of continuous measurements using carbon monoxide as a proxy for biomass burning. Those events were then analysed and emission factors were calculated for CO2, CO, CH4, N2O, NOx and aerosols (Aitken and Accumulation mode, and chemical speciation), along with the modified combustion efficiency (MCE). Upon review of the emission factors, smoke events could then be classified in 3 groups: high MCE events (0.98) were characterised by emission factors typical of savanna grass fires while low MCE events (0.88) were characteristic of shrub fires. Intermediate MCE events (0.93) were found not to reflect any distinct vegetation type. This presentation will outline the campaign and present emission factors of trace and reactive gases as well as the first emission factors for aerosols reported for Australian savanna fires.

  16. GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities

    SciTech Connect

    Friedrich, Elena Trois, Cristina

    2013-11-15

    Highlights: • GHG emission factors for local recycling of municipal waste are presented. • GHG emission factors for two composting technologies for garden waste are included. • Local GHG emission factors were compared to international ones and discussed. • Uncertainties and limitations are presented and areas for new research highlighted. - Abstract: GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from −290 kg CO{sub 2} e (glass) to −19 111 kg CO{sub 2} e (metals – Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186 kg CO{sub 2} e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard.

  17. Integral emission factors for methane determined using urban flux measurements and local-scale inverse models

    NASA Astrophysics Data System (ADS)

    Christen, Andreas; Johnson, Mark; Molodovskaya, Marina; Ketler, Rick; Nesic, Zoran; Crawford, Ben; Giometto, Marco; van der Laan, Mike

    2013-04-01

    The most important long-lived greenhouse gas (LLGHG) emitted during combustion of fuels is carbon dioxide (CO2), however also traces of the LLGHGs methane (CH4) and nitrous oxide (N2O) are released, the quantities of which depend largely on the conditions of the combustion process. Emission factors determine the mass of LLGHGs emitted per energy used (or kilometre driven for cars) and are key inputs for bottom-up emission modelling. Emission factors for CH4 are typically determined in the laboratory or on a test stand for a given combustion system using a small number of samples (vehicles, furnaces), yet associated with larger uncertainties when scaled to entire fleets. We propose an alternative, different approach - Can integrated emission factors be independently determined using direct micrometeorological flux measurements over an urban surface? If so, do emission factors determined from flux measurements (top-down) agree with up-scaled emission factors of relevant combustion systems (heating, vehicles) in the source area of the flux measurement? Direct flux measurements of CH4 were carried out between February and May, 2012 over a relatively densely populated, urban surface in Vancouver, Canada by means of eddy covariance (EC). The EC-system consisted of an ultrasonic anemometer (CSAT-3, Campbell Scientific Inc.) and two open-path infrared gas analyzers (Li7500 and Li7700, Licor Inc.) on a tower at 30m above the surface. The source area of the EC system is characterised by a relative homogeneous morphometry (5.3m average building height), but spatially and temporally varying emission sources, including two major intersecting arterial roads (70.000 cars drive through the 50% source area per day) and seasonal heating in predominantly single-family houses (natural gas). An inverse dispersion model (turbulent source area model), validated against large eddy simulations (LES) of the urban roughness sublayer, allows the determination of the spatial area that

  18. Nitrous oxide emissions from intensive agricultural systems: Variations between crops and seasons, key driving variables, and mean emission factors

    NASA Astrophysics Data System (ADS)

    Dobbie, K. E.; McTaggart, I. P.; Smith, K. A.

    1999-11-01

    Emissions of nitrous oxide from intensively managed agricultural fields were measured over 3 years. Exponential increases in flux occurred with increasing soil water- filled pore space (WFPS) and temperature; increases in soil mineral N content due to fertilizer application also stimulated emissions. Fluxes were low when any of these variables was below a critical value. The largest fluxes occurred when WFPS values were very high (70-90%), indicating that denitrification was the major process responsible. The relationships with the driving variables showed strong similarities to those reported for very different environments: irrigated sugar cane crops, pastures, and forest in the tropics. Annual emissions varied widely (0.3-18.4 kg N2O-N ha-1). These variations were principally due to the degree of coincidence of fertilizer application and major rainfall events. It is concluded therefore that several years' data are required from any agricultural ecosystem in a variable climate to obtain a robust estimate of mean N2O fluxes. The emissions from small-grain cereals (winter wheat and spring barley) were consistently lower (0.2-0.7 kg N2O-N per 100 kg N applied) than from cut grassland (0.3-5.8 kg N2O- N per 100 kg N). Crops such as broccoli and potatoes gave emissions of the same order as those from the grassland. Although these differences between crop types are not apparent in general data comparisons, there may well be distinct regional differences in the relative and absolute emissions from different crops, due to local factors relating to soil type, weather patterns, and agricultural management practices. This will only be determined by more detailed comparative studies.

  19. Greenhouse gases and other airborne pollutants from household stoves in China: a database for emission factors

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Smith, K. R.; Ma, Y.; Ye, S.; Jiang, F.; Qi, W.; Liu, P.; Khalil, M. A. K.; Rasmussen, R. A.; Thorneloe, S. A.

    Emissions from household stoves, especially those using solid fuels, can contribute significantly to greenhouse gas (GHG) inventories and have adverse health impacts. Few data are available on emissions from the numerous types of cookstoves used in developing countries. We have systematically measured emissions from 56 fuel/stove combinations in India and China, a large fraction of the combinations in use world-wide. A database was generated containing emission factors of direct and indirect GHGs and other airborne pollutants such as CO 2, CO, CH 4, TNMHC, N 2O, SO 2, NO x, TSP, etc. In this paper, we report on the 28 fuel/stove combinations tested in China. Since fuel and stove parameters were measured simultaneously along with the emissions, the database allows construction of complete carbon balances and analyses of the trade-off of emissions per unit fuel mass and emissions per delivered energy. Results from the analyses show that the total emissions per unit delivered energy were substantially greater from burning the solid fuels than from burning the liquid or gaseous fuels, due to lower thermal and combustion efficiencies for solid-fuel/stove combinations. For a given biomass fuel type, increasing overall stove efficiency tends to increase emissions of products of incomplete combustion. Biomass fuels are typically burned with substantial production of non-CO 2 GHGs with greater radiative forcing, indicating that biomass fuels have the potential to produce net global warming commitments even when grown renewably.

  20. Measurements of black and organic carbon emission factors for household coal combustion in China: implication for emission reduction.

    PubMed

    Chen, Yingjun; Zhi, Guorui; Feng, Yanli; Liu, Dongyan; Zhang, Gan; Li, Jun; Sheng, Guoying; Fu, Jiamo

    2009-12-15

    Household coal combustion is considered as the greatest emission source for black carbon (BC) and an important source for organic carbon (OC) in China. However, measurements on BC and OC emission factors (EF(BC) and EF(OC)) are still scarce, which result in large uncertainties in emission estimates. In this study, a detailed data set of EF(BC) and EF(OC) for household coal burning was presented on the basis of 38 coal/stove combination experiments. These experiments included 13 coals with a wide coverage of geological maturity which were tested in honeycomb-coal-briquette and raw-coal-chunk forms in three typical coal stoves. Averaged values of EF(BC) are 0.004 and 0.007 g/kg for anthracite in briquette and chunk forms and 0.09 and 3.05 g/kg for bituminous coal, respectively; EF(OC) are 0.06 and 0.10 g/kg for anthracite and 3.74 and 5.50 g/kg for bituminous coal in both forms, respectively. Coal maturity was found to be the most important influencing factor relative to coal's burning forms and the stove's burning efficiency, and when medium-volatile bituminous coals (MVB) are excluded from use, averaged EF(BC) and EF(OC) for bituminous coal decrease by 50% and 30%, respectively. According to these EFs, China's BC and OC emissions from the household sector in 2000 were 94 and 244 gigagrams (Gg), respectively. Compared with previous BC emission estimates for this sector (e.g., 465 Gg by Ohara et al., Atmos. Chem. Phys. 2007, 7, 4419-4444), a dramatic decrease was observed and was mainly attributed to the update of EFs. As suggested by this study, if MVB is prohibited as household fuel together with further promotion of briquettes, BC and OC emissions in this sector will be reduced by 80% and 34%, respectively, and then carbonaceous emissions can be controlled to a large extent in China.

  1. Measurements of black and organic carbon emission factors for household coal combustion in China: implication for emission reduction.

    PubMed

    Chen, Yingjun; Zhi, Guorui; Feng, Yanli; Liu, Dongyan; Zhang, Gan; Li, Jun; Sheng, Guoying; Fu, Jiamo

    2009-12-15

    Household coal combustion is considered as the greatest emission source for black carbon (BC) and an important source for organic carbon (OC) in China. However, measurements on BC and OC emission factors (EF(BC) and EF(OC)) are still scarce, which result in large uncertainties in emission estimates. In this study, a detailed data set of EF(BC) and EF(OC) for household coal burning was presented on the basis of 38 coal/stove combination experiments. These experiments included 13 coals with a wide coverage of geological maturity which were tested in honeycomb-coal-briquette and raw-coal-chunk forms in three typical coal stoves. Averaged values of EF(BC) are 0.004 and 0.007 g/kg for anthracite in briquette and chunk forms and 0.09 and 3.05 g/kg for bituminous coal, respectively; EF(OC) are 0.06 and 0.10 g/kg for anthracite and 3.74 and 5.50 g/kg for bituminous coal in both forms, respectively. Coal maturity was found to be the most important influencing factor relative to coal's burning forms and the stove's burning efficiency, and when medium-volatile bituminous coals (MVB) are excluded from use, averaged EF(BC) and EF(OC) for bituminous coal decrease by 50% and 30%, respectively. According to these EFs, China's BC and OC emissions from the household sector in 2000 were 94 and 244 gigagrams (Gg), respectively. Compared with previous BC emission estimates for this sector (e.g., 465 Gg by Ohara et al., Atmos. Chem. Phys. 2007, 7, 4419-4444), a dramatic decrease was observed and was mainly attributed to the update of EFs. As suggested by this study, if MVB is prohibited as household fuel together with further promotion of briquettes, BC and OC emissions in this sector will be reduced by 80% and 34%, respectively, and then carbonaceous emissions can be controlled to a large extent in China. PMID:20000546

  2. Ammonia emissions and emission factors of naturally ventilated dairy housing with solid floors and an outdoor exercise area in Switzerland

    NASA Astrophysics Data System (ADS)

    Schrade, Sabine; Zeyer, Kerstin; Gygax, Lorenz; Emmenegger, Lukas; Hartung, Eberhard; Keck, Margret

    2012-02-01

    From an agricultural and environmental policy perspective there is a pressing need for up-to-date emission data on ammonia (NH 3) from dairy farming. The main aim of this study was to determine NH 3 emissions for the most common dairy farming situation in Switzerland of loose housing with an outdoor exercise area. Measurements were taken on six commercial farms, in naturally ventilated cubicle loose housing systems with solid floors and an outdoor exercise area located alongside the housing. The variation in climate over the course of a year was covered by a total of twelve measuring periods, in two out of three seasons (summer, transition period, winter) per farm. A tracer ratio method with two tracer gases (SF 6, SF 5CF 3) was employed to determine emissions from two areas of different source intensity. A variety of accompanying parameters was used to characterise each measuring situation and to derive the relevant influencing variables. The daily average NH 3 emission across all farms varied from 31 to 67 g LU -1 d -1 in summer, from 16 to 44 g LU -1 d -1 in the transition period, and from 6 to 23 g LU -1 d -1 in winter (1 LU = 500 kg live weight). From a linear mixed-effects model the wind speed in the housing ( p < 0.001) and the interaction of outside temperature and the urea content of the tank milk ( p < 0.001) emerged as significant variables influencing NH 3 emission. A model-based calculation with bootstrapped variance components was used to calculate yearly averaged emission factors for two mountain and plain regions and two wind speeds (0.3 and 0.5 m s -1). The model input was based on milk urea contents from commercial dairy farms and air temperatures over a five-year period. The calculated NH 3 emission factors, which thus accounted for regional differences due to climatic conditions and feeding levels, ranged between 22 and 25 g LU -1 d -1.

  3. Seasonality in fire emission factors using satellite observations of CO and NO2

    NASA Astrophysics Data System (ADS)

    Castellanos, P.; Boersma, K. F.; van der Werf, G.

    2012-12-01

    Burning of vegetation for deforestation, agriculture, land management, and other purposes releases large amounts of trace gases and aerosols into the atmosphere, clearly visible in satellite data records. While burned area and active fire observations in combination with biogeochemical models can provide constraints on the timing, spatial extent, and total fuel consumed by fires, further calculation of trace gas emissions from fires requires partitioning of total fuel consumed into different trace gases using emission factors. In the current formulation of Global Fire Emissions Database (GFED), emissions factors vary by biome but do not vary in time. This is because only a few direct measurements of these emissions factors exist, and of those none encompass a full fire season. In this work, we take advantage of the long data records of CO and NO2 tropospheric columns from the MOPITT and OMI satellites, respectively, to better characterize the seasonal variability of these trace gas emissions from fires. Field measurements have shown that the emissions factors of CO and NO2 are inversely related and are dependent on fuel characteristics and ambient conditions. We analyze a 6-year monthly climatology (2005-2010) of CO to NO2 ratios over important fire regions: central Amazonia, northern Australia, equatorial Africa, and southern Africa. We use the TM5 chemical transport model to separate the fire emissions signal from background variability and the contributions from lightning NOx and anthropogenic emissions. We find that in general the CO:NO2 ratio decreases over the course of the fire season and is correlated with the minimum in rainfall, possibly indicating an increase in flaming combustion, and an increase (decrease) in NOx (CO) emissions factors as fuel beds become dryer. We also analyze trends in fire-isolated NO2 and CO concentrations and find indications of increasing emissions from fires in northern Africa. These results can be used as large-scale indicators

  4. Factors affecting temporal H2S emission at construction and demolition (C&D) debris landfills.

    PubMed

    Xu, Qiyong; Townsend, Timothy

    2014-02-01

    Odor problems associated with H2S emissions often result in odor complaints from nearby residents of C&D debris landfills, especially in the early morning. As part of a field study conducted on H2S removal ability using different cover materials, daily and seasonal H2S emissions through a soil cover layer were monitored at a C&D debris landfill to investigate factors affecting H2S emissions. H2S emission rates were not a constant, but varied seasonally, with an average emission rate of 4.67×10(-6)mgm(-2)s(-1). During a the 10-month field study, as the H2S concentration increased from 140ppm to about 3500ppm underneath the cover soil in the testing cell, H2S emissions ranged from zero to a maximum emission rate of 1.24×10(-5)mgm(-2)s(-1). Continuous emission monitoring indicated that H2S emissions even changed over time throughout the day, generally increasing from morning to afternoon, and were affected by soil moisture and temperature. Laboratory experiments were also conducted to investigate the effects of H2S concentration and cover soil moisture content on H2S emissions. The results showed that increased soil moisture reduced H2S emissions by retarding H2S migration through cover soil and dissolving H2S into soil water. The field study also indicated that due to atmospheric dispersion, high H2S emissions may not cause odor problems.

  5. Source Apportionment of Stack Emissions from Research and Development Facilities Using Positive Matrix Factorization

    SciTech Connect

    Ballinger, Marcel Y.; Larson, Timothy V.

    2014-08-19

    Emissions from research and development (R&D) facilities are difficult to characterize due to the wide variety of processes used, changing nature of research, and large number of chemicals. Positive matrix factorization (PMF) was applied to volatile organic compounds (VOCs) concentrations measured in the main exhaust stacks of four different R&D buildings to identify the number and composition of major contributing sources. PMF identified from 9-11 source-related factors contributing to the stack emissions depending on the building. The factors that were similar between buildings were major contributors to trichloroethylene (TCE), acetone, and ethanol emissions. Several other factors had similar profiles for two or more buildings but not for all four. One factor for each building was a combination of p/m-xylene, o-xylene and ethylbenzene. At least one factor for each building was identified that contained a broad mix of many species and constraints were used in PMF to modify the factors to resemble more closely the off-shift concentration profiles. PMF accepted the constraints with little decrease in model fit. Although the PMF model predicted the profiles of the off-shift samples, the percent of total emissions was under-predicted by the model versus the measured data.

  6. Improving and disaggregating N2O emission factors for ruminant excreta on temperate pasture soils.

    PubMed

    Krol, D J; Carolan, R; Minet, E; McGeough, K L; Watson, C J; Forrestal, P J; Lanigan, G J; Richards, K G

    2016-10-15

    Cattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N2O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N2O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N2O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12months to generate annual N2O emission factors. The EFs from urine treated soil was greater (0.30-4.81% for real urine and 0.13-3.82% for synthetic urine) when compared with dung (-0.02-1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N2O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type.

  7. Improving and disaggregating N2O emission factors for ruminant excreta on temperate pasture soils.

    PubMed

    Krol, D J; Carolan, R; Minet, E; McGeough, K L; Watson, C J; Forrestal, P J; Lanigan, G J; Richards, K G

    2016-10-15

    Cattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N2O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N2O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N2O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12months to generate annual N2O emission factors. The EFs from urine treated soil was greater (0.30-4.81% for real urine and 0.13-3.82% for synthetic urine) when compared with dung (-0.02-1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N2O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type. PMID:27300566

  8. Use of AERMOD to Determine a Hydrogen Sulfide Emission Factor for Swine Operations by Inverse Modeling.

    PubMed

    O'Shaughnessy, Patrick T; Altmaier, Ralph

    2011-08-01

    This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 µg/m(2)-s was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 × 10(-7) µg/yr-m(2)-kg was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1M kg), concentrations 0.5 km from the CAFO were 35 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels.

  9. Use of AERMOD to determine a hydrogen sulfide emission factor for swine operations by inverse modeling

    NASA Astrophysics Data System (ADS)

    O'Shaughnessy, Patrick T.; Altmaier, Ralph

    2011-09-01

    This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 μg m -2 s -1 was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 × 10 -7 μg yr -1 m -2 kg -1 was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1 M kg), concentrations within 0.5 km from the CAFO exceeded 25 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels.

  10. Use of AERMOD to Determine a Hydrogen Sulfide Emission Factor for Swine Operations by Inverse Modeling.

    PubMed

    O'Shaughnessy, Patrick T; Altmaier, Ralph

    2011-08-01

    This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 µg/m(2)-s was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 × 10(-7) µg/yr-m(2)-kg was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1M kg), concentrations 0.5 km from the CAFO were 35 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels. PMID:21804761

  11. Use of AERMOD to Determine a Hydrogen Sulfide Emission Factor for Swine Operations by Inverse Modeling

    PubMed Central

    O’Shaughnessy, Patrick T.; Altmaier, Ralph

    2011-01-01

    This study was conducted to determine both optimal settings applied to the plume dispersion model, AERMOD, and a scalable emission factor for accurately determining the spatial distribution of hydrogen sulfide concentrations in the vicinity of swine concentrated animal feeding operations (CAFOs). These operations emit hydrogen sulfide from both housing structures and waste lagoons. With ambient measurements made at 4 stations within 1 km of large swine CAFOs in Iowa, an inverse-modeling approach applied to AERMOD was used to determine hydrogen sulfide emission rates. CAFO buildings were treated as volume sources whereas nearby lagoons were modeled as area sources. The robust highest concentration (RHC), calculated for both measured and modeled concentrations, was used as the metric for adjusting the emission rate until the ratio of the two RHC levels was unity. Utilizing this approach, an average emission flux rate of 0.57 µg/m2-s was determined for swine CAFO lagoons. Using the average total animal weight (kg) of each CAFO, an average emission factor of 6.06 × 10−7 µg/yr-m2-kg was calculated. From studies that measured either building or lagoon emission flux rates, building fluxes, on a floor area basis, were considered equal to lagoon flux rates. The emission factor was applied to all CAFOs surrounding the original 4 sites and surrounding an additional 6 sites in Iowa, producing an average modeled-to-measured RHC ratio of 1.24. When the emission factor was applied to AERMOD to simulate the spatial distribution of hydrogen sulfide around a hypothetical large swine CAFO (1M kg), concentrations 0.5 km from the CAFO were 35 ppb and dropped to 2 ppb within 6 km of the CAFO. These values compare to a level of 30 ppb that has been determined by the State of Iowa as a threshold level for ambient hydrogen sulfide levels. PMID:21804761

  12. Modeling Nitrous Oxide emissions and identifying emission controlling factors for a spruce forest ecosystem on drained organic soil

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Kasimir, Åsa; Jansson, Per-Erik; Svensson, Magnus; Meyer, Astrid; Klemedtsson, Leif

    2015-04-01

    High Nitrous Oxide (N2O) emission has been identified in hemiboreal forests on drained organic soils. However, the controlling factors regulating the emissions have been unclear. To examine the importance of different factors on the N2O emission in a spruce forest on drained organic soil, a process-based model, CoupModel, was calibrated by the generalized likelihood uncertainty estimation (GLUE) method. The calibrated model reproduced most of the high resolution data (total net radiation, soil temperature, groundwater level, net ecosystem exchange, etc.) very well, as well as accumulated measured N2O emissions, but showed difficulties to capture all the measured emission peaks. Parameter uncertainties could be reduced by combining selected criteria with the measurement data. The model showed the N2O emissions during the summer to be controlled mainly by the competition between plants and microbes while during the winter season snow melt periods are important. The simulated N budget shows >100 kg N ha-1 yr-1 to be in circulation between soil and plants and back again. Each year the peat mineralization adds about 60 kg N ha-1 and atmospheric deposition 12 kg N ha-1. Most of the mineralized litter and peat N is directly taken up by the plants but only a part accumulates in the plant biomass. As long as no timber is harvested the main N loss from the system is through nitrate leaching (30 kg N ha-1 yr-1) and gas emissions (20 kg N ha-1 yr-1), 55% as NO, 27% as N2O and 18% as N2. Regarding N2O gas emissions, our modeling indicates denitrification to be the most responsible process, of the size 6 kg N ha-1 yr-1, which could be compared to 0.04 kg N ha-1 yr-1 from nitrification. Our modelling also reveal 88% of the N2O mainly to be produced by denitrification in the capillary fringe (c.a. 40-60 cm below soil surface) of the anaerobic zone using nitrate produced in the upper more aerobic layers. We conclude N2O production/emission to be controlled mainly by the complex

  13. A Prescribed Fire Emission Factors Database for Land Management and Air Quality Applications

    NASA Astrophysics Data System (ADS)

    Lincoln, E.; Hao, W.; Baker, S.; Yokelson, R. J.; Burling, I. R.; Urbanski, S. P.; Miller, W.; Weise, D. R.; Johnson, T. J.

    2010-12-01

    Prescribed fire is a significant emissions source in the U.S. and that needs to be adequately characterized in atmospheric transport/chemistry models. In addition, the Clean Air Act, its amendments, and air quality regulations require that prescribed fire managers estimate the quantity of emissions that a prescribed fire will produce. Several published papers contain a few emission factors for prescribed fire and additional results are found in unpublished documents whose quality has to be assessed. In conjunction with three research projects developing detailed new emissions data and meteorological tools to assist prescribed fire managers, the Strategic Environmental Research and Development Program (SERDP) is supporting development of a database that contains emissions information related to prescribed burning. Ultimately, this database will be available on the Internet and will contain older emissions information that has been assessed and newer emissions information that has been developed from both laboratory-scale and field measurements. The database currently contains emissions information from over 300 burns of different wildland vegetation types, including grasslands, shrublands, woodlands, forests, and tundra over much of North America. A summary of the compiled data will be presented, along with suggestions for additional categories.

  14. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles

    NASA Astrophysics Data System (ADS)

    Brady, J.; Crisp, T. A.; Collier, S.; Kuwayama, T.; Zhang, Q.; Kleeman, M.; Bertram, T. H.

    2013-12-01

    Recent work has demonstrated the potential for vehicle based anthropogenic sources of the carcinogen isocyanic acid (HNCO) in urban environments. Although emission factors for HNCO have recently been measured for light duty diesel vehicles, light duty gasoline vehicles are not well characterized. Here we will present real-time emission factor measurements of HNCO for light duty gasoline vehicles measured at the California Air Resource Board's Haagen-Smit Laboratory in September of 2011 driven on a chassis dynamometer using the California Unified Driving Cycle. Emission factors for HNCO were determined for eight light duty gasoline vehicles utilizing a fast response chemical ionization time-of-flight mass spectrometer and simultaneous real-time measurements of CO, CO2, and NOx. We will discuss the potential production mechanism for HNCO by light duty gasoline vehicles as well as the potential drive cycle dependency of HNCO production.

  15. Seasonal and diel variations of ammonia and methane emissions from a naturally ventilated dairy building and the associated factors influencing emissions.

    PubMed

    Saha, C K; Ammon, C; Berg, W; Fiedler, M; Loebsin, C; Sanftleben, P; Brunsch, R; Amon, T

    2014-01-15

    Understanding seasonal and diel variations of ammonia (NH3) and methane (CH4) emissions from a naturally ventilated dairy (NVD) building may lead to develop successful control strategies for reducing emissions throughout the year. The main objective of this study was to quantify seasonal and diel variations of NH3 and CH4 emissions together with associated factors influencing emissions. Measurements were carried out with identical experimental set-up to cover three winter, spring and summer seasons, and two autumn seasons in the years 2010, 2011, and 2012. The data from 2010 and 2011 were used for developing emission prediction models and the data from 2012 were used for model validation. The results showed that NH3 emission varied seasonally following outside temperature whereas CH4 emission did not show clear seasonal trend. Diel variation of CH4 emission was less pronounced than NH3. The average NH3 and CH4 emissions between 6a.m. and 6p.m. were 66% and 33% higher than the average NH3 and CH4 emissions between 6p.m. and 6a.m., respectively for all seasons. The significant relationships (P<0.0001) between NH3 and influencing factors were found including outside temperature, humidity, wind speed and direction, hour of the day and day of the year. The significant effect (P<0.0001) of climate factors, hours of the day and days of the year on CH4 emission might be directly related to activities of the cows.

  16. Measurements of air pollution emission factors for marine transportation in SECA

    NASA Astrophysics Data System (ADS)

    Alföldy, B.; Lööv, J. B.; Lagler, F.; Mellqvist, J.; Berg, N.; Beecken, J.; Weststrate, H.; Duyzer, J.; Bencs, L.; Horemans, B.; Cavalli, F.; Putaud, J.-P.; Janssens-Maenhout, G.; Csordás, A. P.; Van Grieken, R.; Borowiak, A.; Hjorth, J.

    2013-07-01

    The chemical composition of the plumes of seagoing ships was measured during a two week long measurement campaign in the port of Rotterdam, Hoek van Holland The Netherlands, in September 2009. Altogether, 497 ships were monitored and a statistical evaluation of emission factors (g kg-1 fuel) was provided. The concerned main atmospheric components were SO2, NO2, NOx and the aerosol particle number. In addition, the elemental and water-soluble ionic composition of the emitted particulate matter was determined. Emission factors were expressed as a function of ship type, power and crankshaft rotational speed. The average SO2 emission factor was found to be roughly half of what is allowed in sulphur emission control areas (16 vs. 30 g kg-1 fuel), and exceedances of this limit were rarely registered. A significant linear relationship was observed between the SO2 and particle number emission factors. The intercept of the regression line, 4.8 × 1015 (kg fuel)-1, gives the average number of particles formed during the burning of 1 kg zero sulphur content fuel, while the slope, 2 × 1018, provides the average number of particles formed with 1 kg sulphur burnt with the fuel. Water-soluble ionic composition analysis of the aerosol samples from the plumes showed that ~144 g of particulate sulphate was emitted from 1 kg sulphur burnt with the fuel. The mass median diameter of sulphate particles estimated from the measurements was ~42 nm.

  17. Remote measurement of diesel locomotive emission factors and particle size distributions

    NASA Astrophysics Data System (ADS)

    Johnson, G. R.; Jayaratne, E. R.; Lau, J.; Thomas, V.; Juwono, A. M.; Kitchen, B.; Morawska, L.

    2013-12-01

    A technique for analysing exhaust emission plumes from unmodified locomotives under real world conditions is described and applied to the task of characterizing plumes from railway trains servicing an Australian shipping port. The method utilizes the simultaneous measurement, downwind of the railway line, of the following pollutants; particle number, PM2.5 mass fraction, SO2, NOx and CO2, with the last of these being used as an indicator of fuel combustion. Emission factors are then derived, in terms of number of particles and mass of pollutant emitted per unit mass of fuel consumed. Particle number size distributions are also presented. The practical advantages of the method are discussed including the capacity to routinely collect emission factor data for passing trains and to thereby build up a comprehensive real world database for a wide range of pollutants. Samples from 56 train movements were collected, analyzed and presented. The quantitative results for emission factors are: EF(N) = (1.7 ± 1) × 1016 kg-1, EF(PM2.5) = (1.1 ± 0.5) g kg-1, EF(NOx) = (28 ± 14) g kg-1, and EF(SO2) = (1.4 ± 0.4) g kg-1. The findings are compared with comparable previously published work. Statistically significant (p < α, α = 0.05) correlations within the group of locomotives sampled were found between the emission factors for particle number and both SO2 and NOx.

  18. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles.

    PubMed

    Brady, James M; Crisp, Timia A; Collier, Sonya; Kuwayama, Toshihiro; Forestieri, Sara D; Perraud, Véronique; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D; Bertram, Timothy H

    2014-10-01

    Exposure to gas-phase isocyanic acid (HNCO) has been previously shown to be associated with the development of atherosclerosis, cataracts and rheumatoid arthritis. As such, accurate emission inventories for HNCO are critical for modeling the spatial and temporal distribution of HNCO on a regional and global scale. To date, HNCO emission rates from light duty gasoline vehicles, operated under driving conditions, have not been determined. Here, we present the first measurements of real-time emission factors of isocyanic acid from a fleet of eight light duty gasoline-powered vehicles (LDGVs) tested on a chassis dynamometer using the Unified Driving Cycle (UC) at the California Air Resources Board (CARB) Haagen-Smit test facility, all of which were equipped with three-way catalytic converters. HNCO emissions were observed from all vehicles, in contrast to the idealized laboratory measurements. We report the tested fleet averaged HNCO emission factors, which depend strongly on the phase of the drive cycle; ranging from 0.46 ± 0.13 mg kg fuel(-1) during engine start to 1.70 ± 1.77 mg kg fuel(-1) during hard acceleration after the engine and catalytic converter were warm. The tested eight-car fleet average fuel based HNCO emission factor was 0.91 ± 0.58 mg kg fuel(-1), within the range previously estimated for light duty diesel-powered vehicles (0.21-3.96 mg kg fuel(-1)). Our results suggest that HNCO emissions from LDGVs represent a significant emission source in urban areas that should be accounted for in global and regional models. PMID:25198906

  19. Real-time emission factor measurements of isocyanic acid from light duty gasoline vehicles.

    PubMed

    Brady, James M; Crisp, Timia A; Collier, Sonya; Kuwayama, Toshihiro; Forestieri, Sara D; Perraud, Véronique; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D; Bertram, Timothy H

    2014-10-01

    Exposure to gas-phase isocyanic acid (HNCO) has been previously shown to be associated with the development of atherosclerosis, cataracts and rheumatoid arthritis. As such, accurate emission inventories for HNCO are critical for modeling the spatial and temporal distribution of HNCO on a regional and global scale. To date, HNCO emission rates from light duty gasoline vehicles, operated under driving conditions, have not been determined. Here, we present the first measurements of real-time emission factors of isocyanic acid from a fleet of eight light duty gasoline-powered vehicles (LDGVs) tested on a chassis dynamometer using the Unified Driving Cycle (UC) at the California Air Resources Board (CARB) Haagen-Smit test facility, all of which were equipped with three-way catalytic converters. HNCO emissions were observed from all vehicles, in contrast to the idealized laboratory measurements. We report the tested fleet averaged HNCO emission factors, which depend strongly on the phase of the drive cycle; ranging from 0.46 ± 0.13 mg kg fuel(-1) during engine start to 1.70 ± 1.77 mg kg fuel(-1) during hard acceleration after the engine and catalytic converter were warm. The tested eight-car fleet average fuel based HNCO emission factor was 0.91 ± 0.58 mg kg fuel(-1), within the range previously estimated for light duty diesel-powered vehicles (0.21-3.96 mg kg fuel(-1)). Our results suggest that HNCO emissions from LDGVs represent a significant emission source in urban areas that should be accounted for in global and regional models.

  20. Determining size-specific emission factors for environmental tobacco smoke particles

    SciTech Connect

    Klepeis, Neil E.; Apte, Michael G.; Gundel, Lara A.; Sextro, Richard G.; Nazaroff, William W.

    2002-07-07

    Because size is a major controlling factor for indoor airborne particle behavior, human particle exposure assessments will benefit from improved knowledge of size-specific particle emissions. We report a method of inferring size-specific mass emission factors for indoor sources that makes use of an indoor aerosol dynamics model, measured particle concentration time series data, and an optimization routine. This approach provides--in addition to estimates of the emissions size distribution and integrated emission factors--estimates of deposition rate, an enhanced understanding of particle dynamics, and information about model performance. We applied the method to size-specific environmental tobacco smoke (ETS) particle concentrations measured every minute with an 8-channel optical particle counter (PMS-LASAIR; 0.1-2+ micrometer diameters) and every 10 or 30 min with a 34-channel differential mobility particle sizer (TSI-DMPS; 0.01-1+ micrometer diameters) after a single cigarette or cigar was machine-smoked inside a low air-exchange-rate 20 m{sup 3} chamber. The aerosol dynamics model provided good fits to observed concentrations when using optimized values of mass emission rate and deposition rate for each particle size range as input. Small discrepancies observed in the first 1-2 hours after smoking are likely due to the effect of particle evaporation, a process neglected by the model. Size-specific ETS particle emission factors were fit with log-normal distributions, yielding an average mass median diameter of 0.2 micrometers and an average geometric standard deviation of 2.3 with no systematic differences between cigars and cigarettes. The equivalent total particle emission rate, obtained integrating each size distribution, was 0.2-0.7 mg/min for cigars and 0.7-0.9 mg/min for cigarettes.

  1. Nitrous oxide emission factors from N-fertilizer in sugarcane production in Brazil

    NASA Astrophysics Data System (ADS)

    Galdos, M. V.; Siqueira Neto, M.; Feigl, B. J.; Carvalho, J. L.; Cerri, C. E.; Cerri, C. C.

    2013-12-01

    The Brazilian sugarcane production is rapidly expanding due to the increase of global demand for ethanol. Concurrently the necessary inputs to culture, especially N-fertilizer, are growing, since N is one of the key element to maintain sugarcane productivity. However, it is known that N-fertilizer is responsible for the largest share of N2O emissions from agricultural soils. The Intergovernmental Panel on Climate Changes (IPCC) estimated that under favorable climatic conditions approximately 1% of the N-fertilizer applied can be emitted as N2O. Our goal was to estimate N2O emission factors from N-fertilizer used in the sugarcane ratoon for ethanol production. A field study was conducted at the Capuava Mill, located in southeastern Brazil. The experimental design was completely randomized, with four replications in a factorial scheme (2 x 2): two N sources (urea and ammonium nitrate), two application rates (80 and 120 kg ha-1), and a control treatment. N2O concentrations were determined by gas chromatography using a Shimadzu© GC-mini. N2O fluxes were calculated from linear regressions of concentration versus incubation time in the soil static chambers. The N2O emission factor of N-fertilizer was calculated according to the methodology described in the Guidelines for National Greenhouse Gas Inventories (IPCC). Comparatively, ammonium nitrate emitted 45 to 75% less N2O than urea application. There was no significant difference in N2O emission between the two applied rates of urea. Also the N2O emission factor of ammonium nitrate (0.3×0.2%) was lower than that of urea (1.1×0.4%). Our results indicated that on average the N fertilization of sugarcane plantation has an emission factor of 0.7×0.5% suggesting that N-fertilizer management can be used to reduce greenhouse gas emissions in order to improve the sustainability of bioethanol from sugarcane.

  2. Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

    PubMed

    Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

    2016-03-15

    Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration. PMID:26799329

  3. Are emissions of black carbon from gasoline vehicles overestimated? Real-time, in situ measurement of black carbon emission factors.

    PubMed

    Wang, Yang; Xing, Zhenyu; Zhao, Shuhui; Zheng, Mei; Mu, Chao; Du, Ke

    2016-03-15

    Accurately quantifying black carbon (BC) emission factors (EFs) is a prerequisite for estimation of BC emission inventory. BC EFs determined by measuring BC at the roadside or chasing a vehicle on-road may introduce large uncertainty for low emission vehicles. In this study, BC concentrations were measured inside the tailpipe of gasoline vehicles with different engine sizes under different driving modes to determine the respective EFs. BC EFs ranged from 0.005-7.14 mg/kg-fuel under the speeds of 20-70 km/h, 0.05-28.95 mg/kg-fuel under the accelerations of 0.5-1.5m/s(2). Although the water vapor in the sampling stream could result in an average of 12% negative bias, the BC EFs are significantly lower than the published results obtained with roadside or chasing vehicle measurement. It is suggested to conduct measurement at the tailpipe of gasoline vehicles instead of in the atmosphere behind the vehicles to reduce the uncertainty from fluctuation in ambient BC concentration.

  4. Analysis of energy-related CO2 emissions and driving factors in five major energy consumption sectors in China.

    PubMed

    Cui, Erqian; Ren, Lijun; Sun, Haoyu

    2016-10-01

    Continual growth of energy-related CO2 emissions in China has received great attention, both domestically and internationally. In this paper, we evaluated the CO2 emissions in five major energy consumption sectors which were evaluated from 1991 to 2012. In order to analyze the driving factors of CO2 emission change in different sectors, the Kaya identity was extended by adding several variables based on specific industrial characteristics and a decomposition analysis model was established according to the LMDI method. The results demonstrated that economic factor was the leading force explaining emission increase in each sector while energy intensity and sector contribution were major contributors to emission mitigation. Meanwhile, CO2 emission intensity had no significant influence on CO2 emission in the short term, and energy consumption structure had a small but growing negative impact on the increase of CO2 emissions. In addition, the future CO2 emissions of industry from 2013 to 2020 under three scenarios were estimated, and the reduction potential of CO2 emissions in industry are 335 Mt in 2020 under lower-emission scenario while the CO2 emission difference between higher-emission scenario and lower-emission scenario is nearly 725 Mt. This paper can offer complementary perspectives on determinants of energy-related CO2 emission change in different sectors and help to formulate mitigation strategies for CO2 emissions.

  5. Analysis of energy-related CO2 emissions and driving factors in five major energy consumption sectors in China.

    PubMed

    Cui, Erqian; Ren, Lijun; Sun, Haoyu

    2016-10-01

    Continual growth of energy-related CO2 emissions in China has received great attention, both domestically and internationally. In this paper, we evaluated the CO2 emissions in five major energy consumption sectors which were evaluated from 1991 to 2012. In order to analyze the driving factors of CO2 emission change in different sectors, the Kaya identity was extended by adding several variables based on specific industrial characteristics and a decomposition analysis model was established according to the LMDI method. The results demonstrated that economic factor was the leading force explaining emission increase in each sector while energy intensity and sector contribution were major contributors to emission mitigation. Meanwhile, CO2 emission intensity had no significant influence on CO2 emission in the short term, and energy consumption structure had a small but growing negative impact on the increase of CO2 emissions. In addition, the future CO2 emissions of industry from 2013 to 2020 under three scenarios were estimated, and the reduction potential of CO2 emissions in industry are 335 Mt in 2020 under lower-emission scenario while the CO2 emission difference between higher-emission scenario and lower-emission scenario is nearly 725 Mt. This paper can offer complementary perspectives on determinants of energy-related CO2 emission change in different sectors and help to formulate mitigation strategies for CO2 emissions. PMID:27397029

  6. Evaluating near highway air pollutant levels and estimating emission factors: Case study of Tehran, Iran.

    PubMed

    Nayeb Yazdi, Mohammad; Delavarrafiee, Maryam; Arhami, Mohammad

    2015-12-15

    A field sampling campaign was implemented to evaluate the variation in air pollutants levels near a highway in Tehran, Iran (Hemmat highway). The field measurements were used to estimate road link-based emission factors for average vehicle fleet. These factors were compared with results of an in tunnel measurement campaign (in Resalat tunnel). Roadside and in-tunnel measurements of carbon monoxide (CO) and size-fractionated particulate matter (PM) were conducted during the field campaign. The concentration gradient diagrams showed exponential decay, which represented a substantial decay, more than 50-80%, in air pollutants level in a distance between 100 and 150meters (m) of the highway. The changes in particle size distribution by distancing from highway were also captured and evaluated. The results showed particle size distribution shifted to larger size particles by distancing from highway. The empirical emission factors were obtained by using the roadside and in tunnel measurements with a hypothetical box model, floating machine model, CALINE4, CT-EMFAC or COPERT. Average CO emission factors were estimated to be in a range of 4 to 12g/km, and those of PM10 were 0.1 to 0.2g/km, depending on traffic conditions. Variations of these emission factors under real working condition with speeds were determined.

  7. GHG emission factors developed for the recycling and composting of municipal waste in South African municipalities.

    PubMed

    Friedrich, Elena; Trois, Cristina

    2013-11-01

    GHG (greenhouse gas) emission factors for waste management are increasingly used, but such factors are very scarce for developing countries. This paper shows how such factors have been developed for the recycling of glass, metals (Al and Fe), plastics and paper from municipal solid waste, as well as for the composting of garden refuse in South Africa. The emission factors developed for the different recyclables in the country show savings varying from -290kg CO2 e (glass) to -19111kg CO2 e (metals - Al) per tonne of recyclable. They also show that there is variability, with energy intensive materials like metals having higher GHG savings in South Africa as compared to other countries. This underlines the interrelation of the waste management system of a country/region with other systems, in particular with energy generation, which in South Africa, is heavily reliant on coal. This study also shows that composting of garden waste is a net GHG emitter, releasing 172 and 186kg CO2 e per tonne of wet garden waste for aerated dome composting and turned windrow composting, respectively. The paper concludes that these emission factors are facilitating GHG emissions modelling for waste management in South Africa and enabling local municipalities to identify best practice in this regard.

  8. Real-time black carbon emission factor measurements from light duty vehicles.

    PubMed

    Forestieri, Sara D; Collier, Sonya; Kuwayama, Toshihiro; Zhang, Qi; Kleeman, Michael J; Cappa, Christopher D

    2013-11-19

    Eight light-duty gasoline low emission vehicles (LEV I) were tested on a Chassis dynamometer using the California Unified Cycle (UC) at the Haagen-Smit vehicle test facility at the California Air Resources Board in El Monte, CA during September 2011. The UC includes a cold start phase followed by a hot stabilized running phase. In addition, a light-duty gasoline LEV vehicle and ultralow emission vehicle (ULEV), and a light-duty diesel passenger vehicle and gasoline direct injection (GDI) vehicle were tested on a constant velocity driving cycle. A variety of instruments with response times ≥0.1 Hz were used to characterize how the emissions of the major particulate matter components varied for the LEVs during a typical driving cycle. This study focuses primarily on emissions of black carbon (BC). These measurements allowed for the determination of BC emission factors throughout the driving cycle, providing insights into the temporal variability of BC emission factors during different phases of a typical driving cycle. PMID:24156818

  9. Real-time black carbon emission factor measurements from light duty vehicles

    NASA Astrophysics Data System (ADS)

    Forestieri, Sara Danielle

    Eight light-duty gasoline low emission vehicles (LEV I) were tested on a Chassis dynamometer using the California Unified Cycle (UC) at the Haagen-Smit vehicle test facility at the California Air Resources Board in El Monte, CA during September 2011. The UC includes a cold start phase followed by a hot stabilized running phase. In addition, a light-duty gasoline LEV vehicle and ultra-low emission vehicle (ULEV), and a light-duty diesel passenger vehicle and gasoline direct injection (GDI) vehicle were tested on a constant velocity driving cycle. A variety of instruments with response times ≥ 0.1 Hz were used to characterize how the emissions of the major PM components varied for the LEVs during a typical driving cycle. This study focuses primarily on emissions of black carbon (BC). These measurements allowed for the determination of BC emission factors throughout the driving cycle, providing insights into the temporal variability of BC emission factors during different phases of a typical driving cycle.

  10. Evaluation of regional isoprene emission factors and modeled fluxes in California

    NASA Astrophysics Data System (ADS)

    Misztal, Pawel K.; Avise, Jeremy C.; Karl, Thomas; Scott, Klaus; Jonsson, Haflidi H.; Guenther, Alex B.; Goldstein, Allen H.

    2016-08-01

    Accurately modeled biogenic volatile organic compound (BVOC) emissions are an essential input to atmospheric chemistry simulations of ozone and particle formation. BVOC emission models rely on basal emission factor (BEF) distribution maps based on emission measurements and vegetation land-cover data but these critical input components of the models as well as model simulations lack validation by regional scale measurements. We directly assess isoprene emission-factor distribution databases for BVOC emission models by deriving BEFs from direct airborne eddy covariance (AEC) fluxes (Misztal et al., 2014) scaled to the surface and normalized by the activity factor of the Guenther et al. (2006) algorithm. The available airborne BEF data from approx. 10 000 km of flight tracks over California were averaged spatially over 48 defined ecological zones called ecoregions. Consistently, BEFs used by three different emission models were averaged over the same ecoregions for quantitative evaluation. Ecoregion-averaged BEFs from the most current land cover used by the Model of Emissions of Gases and Aerosols from Nature (MEGAN) v.2.1 resulted in the best agreement among the tested land covers and agreed within 10 % with BEFs inferred from measurement. However, the correlation was sensitive to a few discrepancies (either overestimation or underestimation) in those ecoregions where land-cover BEFs are less accurate or less representative for the flight track. The two other land covers demonstrated similar agreement (within 30 % of measurements) for total average BEF across all tested ecoregions but there were a larger number of specific ecoregions that had poor agreement with the observations. Independently, we performed evaluation of the new California Air Resources Board (CARB) hybrid model by directly comparing its simulated isoprene area emissions averaged for the same flight times and flux footprints as actual measured area emissions. The model simulation and the observed

  11. The development of seasonal emission factors from a Canadian commercial laying hen facility

    NASA Astrophysics Data System (ADS)

    Morgan, Robert J.; Wood, David J.; Van Heyst, Bill J.

    2014-04-01

    Pollutants emitted from poultry housing facilities are a concern from a human health, bird welfare, and environmental perspective. Development of emission factors for these aerial pollutants is difficult due to variable climatic conditions, the number and type of poultry, and the wide range of management practices used. To address these concerns, a study was conducted to develop emission factors for ammonia and particulate matter over a period of one year from a commercial poultry laying hen facility in Wellington County, Ontario, Canada. Instruments housed inside an on-site mobile trailer were used to monitor in-house concentrations of ammonia and size fractionated particulate matter via a heated sample line. Along with a ventilation profile, emission factors were developed for the facility. Average emissions of 19.53 ± 19.97, 2.55 ± 2.10, and 1.10 ± 1.52 g day-1 AU-1 (where AU is defined as an animal unit equivalent to 500 kg live mass) for ammonia, PM10, PM2.5, respectively, were observed. All emissions peaked during the winter months, with the exception of PM2.5 which increased in the summer.

  12. Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall

    SciTech Connect

    Maddalena, Randy; Russell, Marion; Apte, Michael G.

    2010-06-01

    Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations.

  13. Estimating carbon dioxide emission factors for the California electric power sector

    SciTech Connect

    Marnay, Chris; Fisher, Diane; Murtishaw, Scott; Phadke, Amol; Price, Lynn; Sathaye, Jayant

    2002-08-01

    The California Climate Action Registry (''Registry'') was initially established in 2000 under Senate Bill 1771, and clarifying legislation (Senate Bill 527) was passed in September 2001. The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) has been asked to provide technical assistance to the California Energy Commission (CEC) in establishing methods for calculating average and marginal electricity emissions factors, both historic and current, as well as statewide and for sub-regions. This study is exploratory in nature. It illustrates the use of three possible approaches and is not a rigorous estimation of actual emissions factors. While the Registry will ultimately cover emissions of all greenhouse gases (GHGs), presently it is focusing on carbon dioxide (CO2). Thus, this study only considers CO2, which is by far the largest GHG emitted in the power sector. Associating CO2 emissions with electricity consumption encounters three major complications. First, electricity can be generated from a number of different primary energy sources, many of which are large sources of CO2 emissions (e.g., coal combustion) while others result in virtually no CO{sub 2} emissions (e.g., hydro). Second, the mix of generation resources used to meet loads may vary at different times of day or in different seasons. Third, electrical energy is transported over long distances by complex transmission and distribution systems, so the generation sources related to electricity usage can be difficult to trace and may occur far from the jurisdiction in which that energy is consumed. In other words, the emissions resulting from electricity consumption vary considerably depending on when and where it is used since this affects the generation sources providing the power. There is no practical way to identify where or how all the electricity used by a certain customer was generated, but by reviewing public sources of data the total emission burden of a customer's electricity

  14. Black carbon particulate matter emission factors for buoyancy-driven associated gas flares.

    PubMed

    McEwen, James D N; Johnson, Matthew R

    2012-03-01

    Flaring is a technique used extensively in the oil and gas industry to burn unwanted flammable gases. Oxidation of the gas can preclude emissions of methane (a potent greenhouse gas); however, flaring creates other pollutant emissions such as particulate matter (PM) in the form of soot or black carbon (BC). Currently available PM emissionfactors for flares were reviewed and found to be questionably accurate, or based on measurements not directly relevant to open-atmosphere flares. In addition, most previous studies of soot emissions from turbulent diffusion flames considered alkene or alkyne based gaseous fuels, and few considered mixed fuels in detail and/or lower sooting propensity fuels such as methane, which is the predominant constituent of gas flared in the upstream oil and gas industry. Quantitative emission measurements were performed on laboratory-scale flares for a range of burner diameters, exit velocities, and fuel compositions. Drawing from established standards, a sampling protocol was developed that employed both gravimetric analysis of filter samples and real-time measurements of soot volume fraction using a laser-induced incandescence (LII) system. For the full range of conditions tested (burner inner diameter [ID] of 12.7-76.2 mm, exit velocity 0.1-2.2 m/sec, 4- and 6-component methane-based fuel mixtures representative of associated gas in the upstream oil industry), measured soot emission factors were less than 0.84 kg soot/10(3) m3 fuel. A simple empirical relationship is presented to estimate the PM emission factor as a function of the fuel heating value for a range of conditions, which, although still limited, is an improvement over currently available emission factors. PMID:22482289

  15. Observations and model simulations of carbon monoxide emission factors from a California highway.

    PubMed

    Held, A E; Chang, D P; Niemeier, D A

    2001-01-01

    A series of twelve intensively monitored 1-hr CO dispersion studies were conducted near Davis, CA, in winter 1996. The experimental equipment included twelve CO sampling ports at elevations up to 50 m, three sonic anemometers, a tethersonde station, aircraft measurements of wind and temperature profile aloft, and a variety of conventional meteorological equipment. The study was designed to explore the role of vehicular exhaust buoyancy during worst-case meteorological conditions, such as low winds oriented in near-parallel alignment with the road during a surface-based nocturnal inversion. From the study, field estimates of the CO emission factor (EF) from a California vehicle fleet were computed using two different methods. The analysis suggests that the CT-EMFAC/EMFAC (EMission FACtor) models currently used to conduct federal conformity modeling significantly overpredict CO emissions for high-speed, free-flowing traffic on California highways. PMID:11218420

  16. 40 CFR Table II-1 to Subpart II of... - Emission Factors

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Emission Factors II Table II-1 to Subpart II of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Wastewater Treatment Pt. 98, Subpt. II, Table...

  17. 40 CFR Table II-1 to Subpart II of... - Emission Factors

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Emission Factors II Table II-1 to Subpart II of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Industrial Wastewater Treatment Pt. 98, Subpt. II, Table...

  18. 40 CFR Table I-1 to Subpart I of... - Default Emission Factors for Threshold Applicability Determination

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Emission Factors for Threshold Applicability Determination I Table I-1 to Subpart I of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING...

  19. 40 CFR Table I-1 to Subpart I - Default Emission Factors for Threshold Applicability Determination

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Default Emission Factors for Threshold Applicability Determination I Table I-1 to Subpart I Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics Manufacturing Pt....

  20. 40 CFR Table I-1 to Subpart I of... - Default Emission Factors for Threshold Applicability Determination

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Default Emission Factors for Threshold Applicability Determination I Table I-1 to Subpart I of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING...

  1. Consideration of Real World Factors Influencing Greenhouse Gas Emissions in ALPHA

    EPA Science Inventory

    Discuss a variety of factors that influence the simulated fuel economy and GHG emissions that are often overlooked and updates made to ALPHA based on actual benchmarking data observed across a range of vehicles and transmissions. ALPHA model calibration is also examined, focusin...

  2. Temporal and modal characterization of DoD source air toxic emission factors: final report

    EPA Science Inventory

    This project tested three, real-/near real-time monitoring techniques to develop air toxic emission factors for Department of Defense (DoD) platform sources. These techniques included: resonance enhanced multi photon ionization time of flight mass spectrometry (REMPI-TOFMS) for o...

  3. Evaluation of factors affecting nitrous oxide emission and N transformation in a sandy loam soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A better understanding of the complex factors affecting nitrous oxide (N2O) emission and potential mitigation practices will assist in developing strategies to improve the sustainability of agricultural production systems. Using surface soil collected from a pomegranate orchard, a series of laborato...

  4. Isoprene Emission Factors for Subtropical Street Trees for Regional Air Quality Modeling.

    PubMed

    Dunn-Johnston, Kristina A; Kreuzwieser, Jürgen; Hirabayashi, Satoshi; Plant, Lyndal; Rennenberg, Heinz; Schmidt, Susanne

    2016-01-01

    Evaluating the environmental benefits and consequences of urban trees supports their sustainable management in cities. Models such as i-Tree Eco enable decision-making by quantifying effects associated with particular tree species. Of specific concern are emissions of biogenic volatile organic compounds, particularly isoprene, that contribute to the formation of photochemical smog and ground level ozone. Few studies have quantified these potential disservices of urban trees, and current models predominantly use emissions data from trees that differ from those in our target region of subtropical Australia. The present study aimed (i) to quantify isoprene emission rates of three tree species that together represent 16% of the inventoried street trees in the target region; (ii) to evaluate outputs of the i-Tree Eco model using species-specific versus currently used, generic isoprene emission rates; and (iii) to evaluate the findings in the context of regional air quality. Isoprene emission rates of (Myrtaceae) and (Proteaceae) were 2.61 and 2.06 µg g dry leaf weight h, respectively, whereas (Sapindaceae) was a nonisoprene emitter. We substituted the generic isoprene emission rates with these three empirical values in i-Tree Eco, resulting in a 182 kg yr (97%) reduction in isoprene emissions, totaling 6284 kg yr when extrapolated to the target region. From these results we conclude that care has to be taken when using generic isoprene emission factors for urban tree models. We recommend that emissions be quantified for commonly planted trees, allowing decision-makers to select tree species with the greatest overall benefit for the urban environment. PMID:26828179

  5. Emission-factor uncertainties in maritime transport in the Strait of Gibraltar, Spain

    NASA Astrophysics Data System (ADS)

    Moreno-Gutiérrez, J.; Durán-Grados, V.; Uriondo, Z.; Ángel Llamas, J.

    2012-08-01

    A reliable and up-to-date maritime emission inventory is essential for atmospheric scientists quantifying the impact of shipping. The objective of this study is to estimate the atmospheric emissions of SO2, NOx, CO2 and PM10 by international merchant shipping in 2007 in the Strait of Gibraltar, Spain, including the Algeciras Bay by two methods. Two methods (both bottom-up) have been used in this study: 1. Establishing engine power-based emission factors (g kWh-1, EPA) or the mass of pollutant per work performed by the engine for each of the relevant components of the exhaust gas from diesel engines and power for each ship. 2. Establishing fuel-based emission factors (kg emitted/t of fuel) or mass of pollutant per mass of combusted fuel for each of the relevant components of the exhaust gas and a fuel-consumption inventory (IMO). In both methods, the means to estimate engine power and fuel-consumption inventories are the same. The exhaust from boilers and incinerators is regarded as a small contributor and excluded. In total, an estimated average of 1 389 111.05 t of CO2, 23 083.09 t of SO2, 32 005.63 t of NOx and 2972 t of PM10 were emitted from January 2007 until December 2007 by international and domestic shipping. The estimated total fuel consumption amounts to 437 405.84 t. The major differences between the estimates generated by the two methods are for NOx (16% in certain cases) and CO (up to 23%). A total difference for all compounds of 3038 t (approximately 2%) has been found between the two methods but it is not areasonable estimate of uncertainty. Therefore, the results for both methods may be considered acceptable because the actual uncontrolled deviations appear in the changes in emission factors that occur for a given engine with age. These deviations are often difficult to quantify and depend on individual shipboard service and maintenance routines. Emission factors for CO and NOx are not constant and depend on engine condition. For example, tests

  6. Emission factors for gaseous and particulate pollutants from offshore diesel engine vessels in China

    NASA Astrophysics Data System (ADS)

    Zhang, Fan; Chen, Yingjun; Tian, Chongguo; Lou, Diming; Li, Jun; Zhang, Gan; Matthias, Volker

    2016-05-01

    Shipping emissions have significant influence on atmospheric environment as well as human health, especially in coastal areas and the harbour districts. However, the contribution of shipping emissions on the environment in China still need to be clarified especially based on measurement data, with the large number ownership of vessels and the rapid developments of ports, international trade and shipbuilding industry. Pollutants in the gaseous phase (carbon monoxide, sulfur dioxide, nitrogen oxides, total volatile organic compounds) and particle phase (particulate matter, organic carbon, elemental carbon, sulfates, nitrate, ammonia, metals) in the exhaust from three different diesel-engine-powered offshore vessels in China (350, 600 and 1600 kW) were measured in this study. Concentrations, fuel-based and power-based emission factors for various operating modes as well as the impact of engine speed on emissions were determined. Observed concentrations and emission factors for carbon monoxide, nitrogen oxides, total volatile organic compounds, and particulate matter were higher for the low-engine-power vessel (HH) than for the two higher-engine-power vessels (XYH and DFH); for instance, HH had NOx EF (emission factor) of 25.8 g kWh-1 compared to 7.14 and 6.97 g kWh-1 of DFH, and XYH, and PM EF of 2.09 g kWh-1 compared to 0.14 and 0.04 g kWh-1 of DFH, and XYH. Average emission factors for all pollutants except sulfur dioxide in the low-engine-power engineering vessel (HH) were significantly higher than that of the previous studies (such as 30.2 g kg-1 fuel of CO EF compared to 2.17 to 19.5 g kg-1 fuel in previous studies, 115 g kg-1 fuel of NOx EF compared to 22.3 to 87 g kg-1 fuel in previous studies and 9.40 g kg-1 fuel of PM EF compared to 1.2 to 7.6 g kg-1 fuel in previous studies), while for the two higher-engine-power vessels (DFH and XYH), most of the average emission factors for pollutants were comparable to the results of the previous studies, engine type was

  7. Research on impacts of population-related factors on carbon emissions in Beijing from 1984 to 2012

    SciTech Connect

    Yang, Yayun; Zhao, Tao; Wang, Yanan Shi, Zhaohui

    2015-11-15

    Carbon emissions related to population factors have aroused great attention around the world. A multitude of literature mainly focused on single demographic impacts on environmental issues at the national level, and comprehensive studies concerning population-related factors at a city level are rare. This paper employed STIRPAT (Stochastic Impacts by Regression on Population, Affluence and Technology) model incorporating PLS (Partial least squares) regression method to examine the influence of population-related factors on carbon emissions in Beijing from 1984 to 2012. Empirically results manifest that urbanization is the paramount driver. Changes in population age structure have significantly positive impacts on carbon emissions, and shrinking young population, continuous expansion of working age population and aging population will keep on increasing environmental pressures. Meanwhile, shrinking household size and expanding floating population boost the discharge of carbon emissions. Besides, per capita consumption is an important contributor of carbon emissions, while industry energy intensity is the main inhibitory factor. Based upon these findings and the specific circumstances of Beijing, policies such as promoting clean and renewable energy, improving population quality and advocating low carbon lifestyles should be enhanced to achieve targeted emissions reductions. - Highlights: • We employed the STIRPAT model to identify population-related factors of carbon emissions in Beijing. • Urbanization is the paramount driver of carbon emissions. • Changes in population age structure exert significantly positive impacts on carbon emissions. • Shrinking household size, expanding floating population and improving consumption level increase carbon emissions. • Industry energy intensity decreases carbon emissions.

  8. Urban Household Carbon Emission and Contributing Factors in the Yangtze River Delta, China

    PubMed Central

    Xu, Xibao; Tan, Yan; Chen, Shuang; Yang, Guishan; Su, Weizhong

    2015-01-01

    Carbon reduction at the household level is an integral part of carbon mitigation. This study analyses the characteristics, effects, contributing factors and policies for urban household carbon emissions in the Yangtze River Delta of China. Primary data was collected through structured questionnaire surveys in three cities in the region – Nanjing, Ningbo, and Changzhou in 2011. The survey data was first used to estimate the magnitude of household carbon emissions in different urban contexts. It then examined how, and to what extent, each set of demographic, economic, behavioral/cognitive and spatial factors influence carbon emissions at the household level. The average of urban household carbon emissions in the region was estimated to be 5.96 tonnes CO2 in 2010. Energy consumption, daily commuting, garbage disposal and long-distance travel accounted for 51.2%, 21.3%, 16.0% and 11.5% of the total emission, respectively. Regulating rapidly growing car-holdings of urban households, stabilizing population growth, and transiting residents’ low-carbon awareness to household behavior in energy saving and other spheres of consumption in the context of rapid population aging and the growing middle income class are suggested as critical measures for carbon mitigation among urban households in the Yangtze River Delta. PMID:25884853

  9. Urban household carbon emission and contributing factors in the Yangtze River Delta, China.

    PubMed

    Xu, Xibao; Tan, Yan; Chen, Shuang; Yang, Guishan; Su, Weizhong

    2015-01-01

    Carbon reduction at the household level is an integral part of carbon mitigation. This study analyses the characteristics, effects, contributing factors and policies for urban household carbon emissions in the Yangtze River Delta of China. Primary data was collected through structured questionnaire surveys in three cities in the region--Nanjing, Ningbo, and Changzhou in 2011. The survey data was first used to estimate the magnitude of household carbon emissions in different urban contexts. It then examined how, and to what extent, each set of demographic, economic, behavioral/cognitive and spatial factors influence carbon emissions at the household level. The average of urban household carbon emissions in the region was estimated to be 5.96 tonnes CO2 in 2010. Energy consumption, daily commuting, garbage disposal and long-distance travel accounted for 51.2%, 21.3%, 16.0% and 11.5% of the total emission, respectively. Regulating rapidly growing car-holdings of urban households, stabilizing population growth, and transiting residents' low-carbon awareness to household behavior in energy saving and other spheres of consumption in the context of rapid population aging and the growing middle income class are suggested as critical measures for carbon mitigation among urban households in the Yangtze River Delta.

  10. Size distribution of polycyclic aromatic hydrocarbon particulate emission factors from agricultural burning

    NASA Astrophysics Data System (ADS)

    Keshtkar, Haleh; Ashbaugh, Lowell L.

    Burning of agricultural waste residue is a common method of disposal when preparing land following crop harvest. This practice introduces volatile organic compounds, including polycyclic aromatic hydrocarbons (PAHs), into the atmosphere. This study examines the particle size distribution in the smoke emissions of two common agricultural waste residues (biofuels) in California, almond prunings and rice straw. The residues were burned in a combustion chamber designed specifically for this purpose, and the smoke emissions were collected on 10-stage MOUDI impactors for analysis of PAH and total particle mass. The results, in units of emission factors, show that combustion temperature is an important factor in determining the smoke particle PAH composition. Total PAH emissions from rice straw burns were 18.6 mg kg -1 of fuel, while the emissions from almond prunings were lower at 8.03 mg kg -1. The less volatile five- and six-ring PAH was predominately on smaller particles where it condensed in the early stages of combustion while the more volatile three- and four-ring PAH formed on larger particles as the smoke cooled.

  11. [Emission of PCDD/Fs from Crematories and Its Influencing Factors].

    PubMed

    Yin, Wen-hua; Yu, Xiao-wei; Han, Jing-lei; Feng, Gui-xian; Fu, Jian-ping; Yang, Yan-yan; Ju, Yong-ming; Zhang, Su-kun

    2015-10-01

    To analysis the influencing factors for the emssions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as structure of crematory, air pollution control device (APCD) and funeral objects, etc, we collected and measured the PCDD/Fs emissions in flue gas from 13 crematories in China. Then we proposed some supervision suggestions on measures of pollution control and management. The results indicated that the emission levels of PCDD/Fs (as the toxic equivalent concentration, TEQ) was ranged in a large gap from 0.027 to 15.8 ng x m(-3), and the average was 3.2 ng x m(-3). Emissions factor of PCDD/Fs (as TEQ) from 13 crematories varied between 45.9 and 22 236 ng x body(-1), and the average was 4 738 ng x body(-1). The emissions of PCDD/Fs from flat incinerators were generally lower, whereas higher ratio up to the national discharge standard, than that of car type incinerators. Congener distribution of PCDD/Fs in flue gas from 13 crematories were different from each other. Since the emission of PCDD/Fs from some crematories remains in high level, it is necessary to control pollution from the source, improve the pollution control technology, and strengthen government supervision, by following measures: 11 cremating funeral objects separately from corpse; 22 adding one PMID:26841590

  12. [Emission of PCDD/Fs from Crematories and Its Influencing Factors].

    PubMed

    Yin, Wen-hua; Yu, Xiao-wei; Han, Jing-lei; Feng, Gui-xian; Fu, Jian-ping; Yang, Yan-yan; Ju, Yong-ming; Zhang, Su-kun

    2015-10-01

    To analysis the influencing factors for the emssions of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as structure of crematory, air pollution control device (APCD) and funeral objects, etc, we collected and measured the PCDD/Fs emissions in flue gas from 13 crematories in China. Then we proposed some supervision suggestions on measures of pollution control and management. The results indicated that the emission levels of PCDD/Fs (as the toxic equivalent concentration, TEQ) was ranged in a large gap from 0.027 to 15.8 ng x m(-3), and the average was 3.2 ng x m(-3). Emissions factor of PCDD/Fs (as TEQ) from 13 crematories varied between 45.9 and 22 236 ng x body(-1), and the average was 4 738 ng x body(-1). The emissions of PCDD/Fs from flat incinerators were generally lower, whereas higher ratio up to the national discharge standard, than that of car type incinerators. Congener distribution of PCDD/Fs in flue gas from 13 crematories were different from each other. Since the emission of PCDD/Fs from some crematories remains in high level, it is necessary to control pollution from the source, improve the pollution control technology, and strengthen government supervision, by following measures: 11 cremating funeral objects separately from corpse; 22 adding one

  13. Urban household carbon emission and contributing factors in the Yangtze River Delta, China.

    PubMed

    Xu, Xibao; Tan, Yan; Chen, Shuang; Yang, Guishan; Su, Weizhong

    2015-01-01

    Carbon reduction at the household level is an integral part of carbon mitigation. This study analyses the characteristics, effects, contributing factors and policies for urban household carbon emissions in the Yangtze River Delta of China. Primary data was collected through structured questionnaire surveys in three cities in the region--Nanjing, Ningbo, and Changzhou in 2011. The survey data was first used to estimate the magnitude of household carbon emissions in different urban contexts. It then examined how, and to what extent, each set of demographic, economic, behavioral/cognitive and spatial factors influence carbon emissions at the household level. The average of urban household carbon emissions in the region was estimated to be 5.96 tonnes CO2 in 2010. Energy consumption, daily commuting, garbage disposal and long-distance travel accounted for 51.2%, 21.3%, 16.0% and 11.5% of the total emission, respectively. Regulating rapidly growing car-holdings of urban households, stabilizing population growth, and transiting residents' low-carbon awareness to household behavior in energy saving and other spheres of consumption in the context of rapid population aging and the growing middle income class are suggested as critical measures for carbon mitigation among urban households in the Yangtze River Delta. PMID:25884853

  14. Analyzing impact factors of CO{sub 2} emissions using the STIRPAT model

    SciTech Connect

    Fan Ying; Liu Lancui; Wu Gang; Wei Yiming . E-mail: ymwei@263.net

    2006-05-15

    Using the STIRPAT model, this paper analyzes the impact of population, affluence and technology on the total CO{sub 2} emissions of countries at different income levels over the period 1975-2000. Our main results show at the global level that economic growth has the greatest impact on CO{sub 2} emissions, and the proportion of the population between ages 15 and 64 has the least impact. The proportion of the population between 15 and 64 has a negative impact on the total CO{sub 2} emissions of countries at the high income level, but the impact is positive at other income levels. This may illustrate the importance of the 'B' in the 'I = PABT'; that is to say that different behavior fashions can greatly influence environmental change. For low-income countries, the impact of GDP per capita on total CO{sub 2} emissions is very great, and the impact of energy intensity in upper-middle income countries is very great. The impact of these factors on the total CO{sub 2} emissions of countries at the high income level is relatively great. Therefore, these empirical results indicate that the impact of population, affluence and technology on CO{sub 2} emissions varies at different levels of development. Thus, policy-makers should consider these matters fully when they construct their long-term strategies for CO{sub 2} abatement.

  15. Emission factors, size distributions, and emission inventories of carbonaceous particulate matter from residential wood combustion in rural China.

    PubMed

    Guofeng, Shen; Siye, Wei; Wen, Wei; Yanyan, Zhang; Yujia, Min; Bin, Wang; Rong, Wang; Wei, Li; Huizhong, Shen; Ye, Huang; Yifeng, Yang; Wei, Wang; Xilong, Wang; Xuejun, Wang; Shu, Tao

    2012-04-01

    Published emission factors (EFs) often vary significantly, leading to high uncertainties in emission estimations. There are few reliable EFs from field measurements of residential wood combustion in China. In this study, 17 wood fuels and one bamboo were combusted in a typical residential stove in rural China to measure realistic EFs of particulate matter (PM), organic carbon (OC), and elemental carbon (EC), as well as to investigate the influence of fuel properties and combustion conditions on the EFs. Measured EFs of PM, OC, and EC (EF(PM), EF(OC), and EF(EC), respectively) were in the range of 0.38-6.4, 0.024-3.0, and 0.039-3.9 g/kg (dry basis), with means and standard derivation of 2.2 ± 1.2, 0.62 ± 0.64, and 0.83 ± 0.69 g/kg, respectively. Shrubby biomass combustion produced higher EFs than tree woods, and both species had lower EFs than those of indoor crop residue burning (p < 0.05). Significant correlations between EF(PM), EF(OC), and EF(EC) were expected. By using a nine-stage cascade impactor, it was shown that size distributions of PM emitted from tree biomass combustions were unimodal with peaks at a diameter less than 0.4 μm (PM(0.4)), much finer than the PM from indoor crop residue burning. Approximately 79.4% of the total PM from tree wood combustion was PM with a diameter less than 2.1 μm (PM(2.1)). PM size distributions for shrubby biomasses were slightly different from those for tree fuels. On the basis of the measured EFs, total emissions of PM, OC, and EC from residential wood combustion in rural China in 2007 were estimated at about 303, 75.7, and 92.0 Gg. PMID:22380753

  16. Fuel-based fine particulate and black carbon emission factors from a railyard area in Atlanta.

    PubMed

    Galvis, Boris; Bergin, Mike; Russell, Armistead

    2013-06-01

    Railyards have the potential to influence localfine particulate matter (aerodynamic diameter < or = 2.5 microm; PM2.5) concentrations through emissions from diesel locomotives and supporting activities. This is of concern in urban regions where railyards are in proximity to residential areas. Northwest of Atlanta, Georgia, Inman and Tilford railyards are located beside residential neighborhoods, industries, and schools. The PM2.5 concentrations near the railyards is the highest measured amongst the state-run monitoring sites (Georgia Environmental Protection Division, 2012; http://www.georgiaair.org/amp/report.php). The authors estimated fuel-based black carbon (BC) and PM2.5 emission factors for these railyards in order to help determine the impact of railyard activities on PM2.5 concentrations, and for assessing the potential benefits of replacing current locomotive engines with cleaner technologies. High-time-resolution measurements of BC, PM2.5, CO2, and wind speed and direction were made at two locations, north and south of the railyards. Emissions factors (i.e., the mass of BC or PM2.5 per gallon of fuel burned) were estimated by using the downwind/upwind difference in concentrations, wavelet analysis, and an event-based approach. By the authors' estimates, diesel-electric engines used in the railyards have average emission factors of 2.8 +/- 0.2 g of BC and 6.0 +/- 0.5 g of PM2.5 per gallon of diesel fuel burned. A broader mix of railyard supporting activities appear to lead to average emission factors of 0.7 +/- 0.03 g of BC and 1.5 +/- 0.1 g of PM2.5 per gallon of diesel fuel burned. Railyard emissions appear to lead to average enhancements of approximately 1.7 +/- 0.1 microg/m3 of PM2.5 and approximately 0.8 +/- 0.01 microg/m3 of BC in neighboring areas on an annual average basis. Uncertainty not quantified in these results could arise mainly from variability in downwind/upwind differences, differences in emissions of the diverse zones within the

  17. CONSTRAINING THE LORENTZ FACTOR OF A RELATIVISTIC SOURCE FROM ITS THERMAL EMISSION

    SciTech Connect

    Zou, Yuan-Chuan; Cheng, K. S.; Wang, F. Y.

    2015-02-20

    We propose a direct and simple method to measure the Lorentz factor of relativistically expanding objects such as gamma-ray bursts (GRBs). Only three measurements, i.e., the thermal component of the emission, the distance, and the variable timescale of the light curve, are used. When the uncertainties are considered, we will obtain a lower limit of the Lorentz factor instead. We apply this method to GRB 090618 and get a lower limit of 22 for the Lorentz factor. This method can be used for any relativistically moving objects, such as GRBs and soft gamma-ray repeaters.

  18. Dust on the Tracks: Diesel PM and dust emission factors from in-service rail

    NASA Astrophysics Data System (ADS)

    Jaffe, D. A.; Thayer, J.; Malashanka, S.; Hof, G.; Putz, J.; Thompson, G.

    2013-12-01

    Recent proposals to increase rail traffic in the Pacific Northwest for coal export highlight the uncertainties in emission factors for Diesel Particulate Matter (DPM) and coal dust. As such, we proposed a project to examine these emission factors at several sites in Washington State. Because local regulatory agencies were not able to support this work, we used 'crowd funding' (Microryza.com) as a means to support this project. Measurements started in July 2013 at a house, approximately 25 meters from the railroad tracks in the Puget Sound region. We measured size segregated PM as a means to separate out the emissions of DPM from coal dust, and combine this with measurements of CO2, and meteorology. We also used a motion activated video camera to identify each train type (freight, passenger, full coal train, empty coal train). Our early data indicate that when a train passes, we see a strong spike in all sizes of particulate matter along with CO2. This spike lasts a few minutes as the train passes. Using 10 second data, we find an excellent correlation (R2 generally 0.8 or better) between PM1 and CO2, with an average slope of ca 1.1 ug/m3 per ppmv (range 0-5.5 ug/m3 per ppmv, n=178). This slope can be used to derive a fuel based DPM emission factor. As we collect more data, we will further examine it to compare to published DPM emission factors for trains and examine whether we can identify a larger size in the aerosol distribution that might be associated with lofting coal dust from uncovered coal trains.

  19. 40 CFR Table W - 4 of Subpart W-Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false 4 of Subpart W-Default Total Hydrocarbon Emission Factors for Underground Natural Gas Storage W Table W Protection of Environment... Total Hydrocarbon Emission Factors for Underground Natural Gas Storage Underground natural gas...

  20. 40 CFR Table W - 3 of Subpart W-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Transmission...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false 3 of Subpart W-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Transmission Compression W Table W Protection of...—Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Transmission Compression...

  1. 40 CFR Table W - 2 of Subpart W-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false 2 of Subpart W-Default Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing W Table W Protection of Environment... Total Hydrocarbon Emission Factors for Onshore Natural Gas Processing Onshore natural gas...

  2. Supplement B to compilation of air pollutant emission factors, volume 1. Stationary point and area sources

    SciTech Connect

    1996-11-01

    This document contains emission factors and process information for more than 200 air pollution source categories. This Supplement to AP-42 addresses pollutant-generating activity from Bituminous And Subbituminous Coal Combustion, Anthracite Coal Combustion, Fuel Oil Combustion, Natural Gas Combustion, Liquefied Petroleum Gas Combustion, Wood Waste Combustion In Boilers, Lignite Combustion, Bagasse Combustion In Sugar Mills, Residential Fireplaces, Residential Wood Stoves, Waste Oil Combustion, Stationary Gas Turbines For Electricity Generation, Heavy-duty Natural Gas-fired Pipeline Compressor Engines And Turbines, Gasoline and Diesel Industrial Engines, Large Stationary Diesel And All Stationary Dual-fuel Engines, Adipic Acid, Cotton Ginning, Alfafalfa Dehydrating, Malt Beverages, Ceramic Products Manufacturing, Electroplating, Wildfires And Prescribed Burning, Emissions From Soils-Greenhouse Gases, Termites-Greenhouse Gases, and Lightning Emissions-Greenhouse Gases.

  3. The Effects of Abiotic Factors on Induced Volatile Emissions in Corn Plants1

    PubMed Central

    Gouinguené, Sandrine P.; Turlings, Ted C.J.

    2002-01-01

    Many plants respond to herbivory by releasing a specific blend of volatiles that is attractive to natural enemies of the herbivores. In corn (Zea mays), this induced odor blend is mainly composed of terpenoids and indole. The induced signal varies with plant species and genotype, but little is known about the variation due to abiotic factors. Here, we tested the effect of soil humidity, air humidity, temperature, light, and fertilization rate on the emission of induced volatiles in young corn plants. Each factor was tested separately under constant conditions for the other factors. Plants released more when standing in dry soil than in wet soil, whereas for air humidity, the optimal release was found at around 60% relative humidity. Temperatures between 22°C and 27°C led to a higher emission than lower or higher temperatures. Light intensity had a dramatic effect. The emission of volatiles did not occur in the dark and increased steadily with an increase in the light intensity. An experiment with an unnatural light-dark cycle showed that the release was fully photophase dependent. Fertilization also had a strong positive effect; the emission of volatiles was minimal when plants were grown under low nutrition, even when results were corrected for plant biomass. Changes in all abiotic factors caused small but significant changes in the relative ratios among the different compounds (quality) in the induced odor blends, except for air humidity. Hence, climatic conditions and nutrient availability can be important factors in determining the intensity and variability in the release of induced plant volatiles. PMID:12114583

  4. Electromagnetic vacuum of complex media: Dipole emission versus light propagation, vacuum energy, and local field factors

    SciTech Connect

    Donaire, M.

    2011-02-15

    We offer a unified approach to several phenomena related to the electromagnetic vacuum of a complex medium made of point electric dipoles. To this aim, we apply the linear response theory to the computation of the polarization field propagator and study the spectrum of vacuum fluctuations. The physical distinction among the local density of states which enter the spectra of light propagation, total dipole emission, coherent emission, total vacuum energy, and Schwinger-bulk energy is made clear. Analytical expressions for the spectrum of dipole emission and for the vacuum energy are derived. Their respective relations with the spectrum of external light and with the Schwinger-bulk energy are found. The light spectrum and the Schwinger-bulk energy are determined by the Dyson propagator. The emission spectrum and the total vacuum energy are determined by the polarization propagator. An exact relationship of proportionality between both propagators is found in terms of local field factors. A study of the nature of stimulated emission from a single dipole is carried out. Regarding coherent emission, it contains two components. A direct one which is transferred radiatively and directly from the emitter into the medium and whose spectrum is that of external light. And an indirect one which is radiated by induced dipoles. The induction is mediated by one (and only one) local field factor. Regarding the vacuum energy, we find that in addition to the Schwinger-bulk energy the vacuum energy of an effective medium contains local field contributions proportional to the resonant frequency and to the spectral line width.

  5. Seasonal and diel variations of ammonia and methane emissions from a naturally ventilated dairy building and the associated factors influencing emissions.

    PubMed

    Saha, C K; Ammon, C; Berg, W; Fiedler, M; Loebsin, C; Sanftleben, P; Brunsch, R; Amon, T

    2014-01-15

    Understanding seasonal and diel variations of ammonia (NH3) and methane (CH4) emissions from a naturally ventilated dairy (NVD) building may lead to develop successful control strategies for reducing emissions throughout the year. The main objective of this study was to quantify seasonal and diel variations of NH3 and CH4 emissions together with associated factors influencing emissions. Measurements were carried out with identical experimental set-up to cover three winter, spring and summer seasons, and two autumn seasons in the years 2010, 2011, and 2012. The data from 2010 and 2011 were used for developing emission prediction models and the data from 2012 were used for model validation. The results showed that NH3 emission varied seasonally following outside temperature whereas CH4 emission did not show clear seasonal trend. Diel variation of CH4 emission was less pronounced than NH3. The average NH3 and CH4 emissions between 6a.m. and 6p.m. were 66% and 33% higher than the average NH3 and CH4 emissions between 6p.m. and 6a.m., respectively for all seasons. The significant relationships (P<0.0001) between NH3 and influencing factors were found including outside temperature, humidity, wind speed and direction, hour of the day and day of the year. The significant effect (P<0.0001) of climate factors, hours of the day and days of the year on CH4 emission might be directly related to activities of the cows. PMID:24012895

  6. Linear regression analysis of emissions factors when firing fossil fuels and biofuels in a commercial water-tube boiler

    SciTech Connect

    Sharon Falcone Miller; Bruce G. Miller

    2007-12-15

    This paper compares the emissions factors for a suite of liquid biofuels (three animal fats, waste restaurant grease, pressed soybean oil, and a biodiesel produced from soybean oil) and four fossil fuels (i.e., natural gas, No. 2 fuel oil, No. 6 fuel oil, and pulverized coal) in Penn State's commercial water-tube boiler to assess their viability as fuels for green heat applications. The data were broken into two subsets, i.e., fossil fuels and biofuels. The regression model for the liquid biofuels (as a subset) did not perform well for all of the gases. In addition, the coefficient in the models showed the EPA method underestimating CO and NOx emissions. No relation could be studied for SO{sub 2} for the liquid biofuels as they contain no sulfur; however, the model showed a good relationship between the two methods for SO{sub 2} in the fossil fuels. AP-42 emissions factors for the fossil fuels were also compared to the mass balance emissions factors and EPA CFR Title 40 emissions factors. Overall, the AP-42 emissions factors for the fossil fuels did not compare well with the mass balance emissions factors or the EPA CFR Title 40 emissions factors. Regression analysis of the AP-42, EPA, and mass balance emissions factors for the fossil fuels showed a significant relationship only for CO{sub 2} and SO{sub 2}. However, the regression models underestimate the SO{sub 2} emissions by 33%. These tests illustrate the importance in performing material balances around boilers to obtain the most accurate emissions levels, especially when dealing with biofuels. The EPA emissions factors were very good at predicting the mass balance emissions factors for the fossil fuels and to a lesser degree the biofuels. While the AP-42 emissions factors and EPA CFR Title 40 emissions factors are easier to perform, especially in large, full-scale systems, this study illustrated the shortcomings of estimation techniques. 23 refs., 3 figs., 8 tabs.

  7. Emission factor of ammonia (NH3) from on-road vehicles in China: tunnel tests in urban Guangzhou

    NASA Astrophysics Data System (ADS)

    Liu, Tengyu; Wang, Xinming; Wang, Boguang; Ding, Xiang; Deng, Wei; Lü, Sujun; Zhang, Yanli

    2014-05-01

    Ammonia (NH3) is the primary alkaline gas in the atmosphere that contributes to formation of secondary particles. Emission of NH3 from vehicles, particularly gasoline powered light duty vehicles equipped with three-way catalysts, is regarded as an important source apart from emissions from animal wastes and soils, yet measured emission factors for motor vehicles are still not available in China, where traffic-related emission has become an increasingly important source of air pollutants in urban areas. Here we present our tunnel tests for NH3 from motor vehicles under ‘real world conditions’ in an urban roadway tunnel in Guangzhou, a central city in the Pearl River Delta (PRD) region in south China. By attributing all NH3 emissions in the tunnel to light-duty gasoline vehicles, we obtained a fuel-based emission rate of 2.92 ± 0.18 g L-1 and a mileage-based emission factor of 229.5 ± 14.1 mg km-1. These emission factors were much higher than those measured in the United States while measured NO x emission factors (7.17 ± 0.60 g L-1 or 0.56 ± 0.05 g km-1) were contrastingly near or lower than those previously estimated by MOBILE/PART5 or COPERT IV models. Based on the NH3 emission factors from this study, on-road vehicles accounted for 8.1% of NH3 emissions in the PRD region in 2006 instead of 2.5% as estimated in a previous study using emission factors taken from the Emission Inventory Improvement Program (EIIP) in the United States.

  8. Emission factors for open and domestic biomass burning for use in atmospheric models

    NASA Astrophysics Data System (ADS)

    Akagi, S. K.; Yokelson, R. J.; Wiedinmyer, C.; Alvarado, M. J.; Reid, J. S.; Karl, T.; Crounse, J. D.; Wennberg, P. O.

    2010-11-01

    Biomass burning (BB) is the second largest source of trace gases and the largest source of primary fine carbonaceous particles in the global troposphere. Many recent BB studies have provided new emission factor (EF) measurements. This is especially true for non methane organic compounds (NMOC), which influence secondary organic aerosol (SOA) and ozone formation. New EF should improve regional to global BB emissions estimates and therefore, the input for atmospheric models. In this work we present an up-to-date, comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has cooled to ambient temperature, but not yet undergone significant photochemical processing. All the emission factors are converted to one standard form (g compound emitted per kg dry biomass burned) using the carbon mass balance method and they are categorized into 14 fuel or vegetation types. We compile a large number of measurements of biomass consumption per unit area for important fire types and summarize several recent estimates of global biomass consumption by the major types of biomass burning. Biomass burning terminology is defined to promote consistency. Post emission processes are discussed to provide a context for the emission factor concept within overall atmospheric chemistry and also highlight the potential for rapid changes relative to the scale of some models or remote sensing products. Recent work shows that individual biomass fires emit significantly more gas-phase NMOC than previously thought and that including additional NMOC can improve photochemical model performance. A detailed global estimate suggests that BB emits at least 400 Tg yr-1 of gas-phase NMOC, which is about 4 times larger than most previous estimates. Selected recent results (e.g. measurements of HONO and the BB tracers HCN and CH3CN) are highlighted and key areas requiring future research are briefly discussed.

  9. Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells

    NASA Astrophysics Data System (ADS)

    Le, M.; Mothersill, C. E.; Seymour, C. B.; Ahmad, S. B.; Armstrong, A.; Rainbow, A. J.; McNeill, F. E.

    2015-08-01

    The luminescence intensity of 340+/- 5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to 90Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1× {{10}4} cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8× {{10}3}+/- 2.5× {{10}3} counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for 90Y activities 14 to 703 μCi where a positive relationship between photoemission and 90Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1× {{10}4} cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

  10. Factors affecting ultraviolet-A photon emission from β-irradiated human keratinocyte cells.

    PubMed

    Le, M; Mothersill, C E; Seymour, C B; Ahmad, S B; Armstrong, A; Rainbow, A J; McNeill, F E

    2015-08-21

    The luminescence intensity of 340±5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to (90)Y β-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from β-irradiated cells. Exposure of 1 x 10(4) cells/5 mL to 703 μCi resulted in maximum UVA photoemission at 44.8 x 10(3)±2.5 x 10(3) counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for (90)Y activities 14 to 703 μCi where a positive relationship between photoemission and (90)Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1 x 10(4) cells/5 mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low β activities (⩽400 μCi). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

  11. [Experimental study on the size spectra and emission factor of ultrafine particle from coal combustion].

    PubMed

    Sun, Zai; Yang, Wen-jun; Xie, Xiao-fang; Chen, Qiu-fang; Cai, Zhi-liang

    2014-12-01

    The emission characteristics of ultrafine particles released from pulverized coal combustion were studied, the size spectra of ultrafine particles (5.6-560 nm) were measured with FMPS (fast mobility particle sizer) on a self-built aerosol experiment platform. Meanwhile, a particle dynamic evolution model was established to obtain the particle deposition rate and the emission rate through the optimized algorithm. Finally, the emission factor was calculated. The results showed that at the beginning of particle generation, the size spectra were polydisperse and complex, the initial size spectra was mainly composed of three modes including 10 nm, 30-40 nm and 100-200 nm. Among them, the number concentration of mode around 10 nm was higher than those of other modes, the size spectrum of around 100-200 nm was lognormal distributed, with a CMD (count median diameter) of around 16 nm. Then, as time went on, the total number concentration was decayed by exponential law, the CMD first increased and then tended to be stable gradually. The calculation results showed that the emission factor of particles from coal combustion under laboratory condition was (5.54 x 10(12) ± 2.18 x 10(12)) unit x g(-1). PMID:25826918

  12. [Experimental study on the size spectra and emission factor of ultrafine particle from coal combustion].

    PubMed

    Sun, Zai; Yang, Wen-jun; Xie, Xiao-fang; Chen, Qiu-fang; Cai, Zhi-liang

    2014-12-01

    The emission characteristics of ultrafine particles released from pulverized coal combustion were studied, the size spectra of ultrafine particles (5.6-560 nm) were measured with FMPS (fast mobility particle sizer) on a self-built aerosol experiment platform. Meanwhile, a particle dynamic evolution model was established to obtain the particle deposition rate and the emission rate through the optimized algorithm. Finally, the emission factor was calculated. The results showed that at the beginning of particle generation, the size spectra were polydisperse and complex, the initial size spectra was mainly composed of three modes including 10 nm, 30-40 nm and 100-200 nm. Among them, the number concentration of mode around 10 nm was higher than those of other modes, the size spectrum of around 100-200 nm was lognormal distributed, with a CMD (count median diameter) of around 16 nm. Then, as time went on, the total number concentration was decayed by exponential law, the CMD first increased and then tended to be stable gradually. The calculation results showed that the emission factor of particles from coal combustion under laboratory condition was (5.54 x 10(12) ± 2.18 x 10(12)) unit x g(-1).

  13. Definition of yearly emission factor of dust and greenhouse gases through continuous measurements in swine husbandry

    NASA Astrophysics Data System (ADS)

    Costa, Annamaria; Guarino, Marcella

    The object of this study was to develop an accurate estimation method to evaluate the contribution of the various compartments of swine husbandry to dust and GHG (greenhouse gases, CO 2, CH 4 and N 2O) emission into the atmosphere during one year of observation. A weaning, a gestation, a farrowing and a fattening room in an intensive pig house were observed in three different periods (Autumn-Winter, Springtime and Summer, monitoring at least 60% of each period (20% at the beginning, in the middle and at the end) of each cycle). During monitoring, live weight, average live weight gain, number of animals and its variation, type of feed and feeding time were taken into account to evaluate their influence on PM 10, or the fraction of suspended particulate matter with an aerodynamic diameter less than or equal to 10 μm [Emission Inventory Guidebook, 2007. B1100 Particle Emissions from Animal Husbandry Activities. Available from: (accessed October 2008)] and to define GHG emission. The selected piggery had a ventilation control system using a free running impeller to monitor continuously real-time environmental and management parameters with an accuracy of 5%. PM 10 concentration was monitored by a sampler (Haz Dust EPAM 5000), either continuously or through traditional gravimetric technique, and the mean value of dust amount collected on the membranes was utilized as a correction factor to be applied to continuously collected data. PM 10 concentration amount incoming from inlets was removed from PM 10 emission calculation, to estimate the real contribution of pig house dust pollution into atmosphere. Mean yearly emission factor of PM 10 was measured in 2 g d -1 LU -1 for the weaning room, 0.09 g d -1 LU -1 for the farrowing room, 2.59 g d -1 LU -1 for the fattening room and 1.23 g d -1 LU -1 for the gestation room. The highest PM 10 concentration and emission per LU was recorded in the fattening compartment

  14. Enhancement factor, electrostatic force and emission current in a nanoneedle emitter

    NASA Astrophysics Data System (ADS)

    Pogorelov, E. G.; Zhbanov, A. I.; Chang, Y.-C.

    2009-01-01

    We consider field emission from carbon nanotubes and other elongated nanostructures. An exact solution for the electrostatic field between a metallic hemi-ellipsoidal needle on a plate (as a cathode) and a flat anode are presented. The basic idea is to replace the cathode by a linearly charged thread in a uniform electric field and to use a set of "image" charges to reproduce the anode. Exact analytical formulas of the electrical field, field enhancement factor, and electrostatic force are found. Using the Fowler-Nordheim theory we obtain an exact analytical formula for the total current. The field enhancement factor, total force and emission current, as well as their distributions on the top of the needle for a wide range of parameters, have been calculated and analyzed.

  15. Development and review of Euro 5 passenger car emission factors based on experimental results over various driving cycles.

    PubMed

    Fontaras, Georgios; Franco, Vicente; Dilara, Panagiota; Martini, Giorgio; Manfredi, Urbano

    2014-01-15

    The emissions of CO2 and regulated pollutants (NOx, HC, CO, PM) of thirteen Euro 5 compliant passenger cars (seven gasoline, six Diesel) were measured on a chassis dynamometer. The vehicles were driven repeatedly over the European type-approval driving cycle (NEDC) and the more dynamic WMTC and CADC driving cycles. Distance-specific emission factors were derived for each pollutant and sub-cycle, and these were subsequently compared to the corresponding emission factors provided by the reference European models used for vehicle emission inventory compilation (COPERT and HBEFA) and put in context with the applicable European emission limits. The measured emissions stayed below the legal emission limits when the type-approval cycle (NEDC) was used. Over the more dynamic cycles (considered more representative of real-world driving) the emissions were consistently higher but in most cases remained below the type-approval limit. The high NOx emissions of Diesel vehicles under real-world driving conditions remain the main cause for environmental concern regarding the emission profile of Euro 5 passenger cars. Measured emissions of NOx exceeded the type-approval limits (up to 5 times in extreme cases) and presented significantly increased average values (0.35 g/km for urban driving and 0.56 g/km for motorway driving). The comparison with the reference models showed good correlation in all cases, a positive finding considering the importance of these tools in emission monitoring and policy-making processes. PMID:24095966

  16. Quantifying baseline emission factors of air pollutants in China's regional power grids.

    PubMed

    Cai, Wenjia; Wang, Can; Jin, Zhugang; Chen, Jining

    2013-04-16

    Drawing lessons from the clean development mechanism (CDM), this paper developed a combined margin methodology to quantify baseline emission factors of air pollutants in China's regional power grids. The simple average of baseline emission factors of SO2, NOX, and PM2.5 in China's six power grids in 2010 were respectively 1.91 kg/MWh, 1.83 kg/MWh and 0.32 kg/MWh. Several low-efficient mitigation technologies, such as low nitrogen oxide burner (LNB), were suggested to be replaced or used together with other technologies in order to virtually decrease the grid's emission factor. The synergies between GHG and air pollution mitigation in China's power sector was also notable. It is estimated that in 2010, that every 1% CO2 reduction in China's power generation sector resulted in the respective coreduction of 1.1%, 0.5%, and 0.8% of SO2, NOX, and PM2.5. Wind is the best technology to achieve the largest amount of coabatement in most parts of China. This methodology is recommended to be used in making comprehensive air pollution control strategies and in cobenefits analysis in future CDM approval processes.

  17. Variability in operation-based NO(x) emission factors with different test routes, and its effects on the real-driving emissions of light diesel vehicles.

    PubMed

    Lee, Taewoo; Park, Junhong; Kwon, Sangil; Lee, Jongtae; Kim, Jeongsoo

    2013-09-01

    The objective of this study is to quantify the differences in NO(x) emissions between standard and non-standard driving and vehicle operating conditions, and to estimate by how much NO(x) emissions exceed the legislative emission limits under typical Korean road traffic conditions. Twelve Euro 3-5 light-duty diesel vehicles (LDDVs) manufactured in Korea were driven on a chassis dynamometer over the standard New European Driving Cycle (NEDC) and a representative Korean on-road driving cycle (KDC). NO(x) emissions, average speeds and accelerations were calculated for each 1-km trip segment, so called averaging windows. The results suggest that the NO(x) emissions of the tested vehicles are more susceptible to variations in the driving cycles than to those in the operating conditions. Even under comparable operating conditions, the NO(x) control capabilities of vehicles differ from each other, i.e., NO(x) control is weaker for the KDC than for the NEDC. The NO(x) emissions over the KDC for given vehicle operating conditions exceed those over the NEDC by more than a factor of 8. Consequently, on-road NO(x) emission factors are estimated here to exceed the Euro 5 emission limit by up to a factor of 8, 4 and 3 for typical Korean urban, rural, and motorway road traffic conditions, respectively. Our findings support the development of technical regulations for supplementary real-world emission tests for emission certification and the corresponding research actions taken by automotive industries. PMID:23747552

  18. Impact of some field factors on inhalation exposure levels to bitumen emissions during road paving operations.

    PubMed

    Deygout, François; Auburtin, Guy

    2015-03-01

    Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch.

  19. Traffic induced particle resuspension in Paris: Emission factors and source contributions

    NASA Astrophysics Data System (ADS)

    Amato, F.; Favez, O.; Pandolfi, M.; Alastuey, A.; Querol, X.; Moukhtar, S.; Bruge, B.; Verlhac, S.; Orza, J. A. G.; Bonnaire, N.; Le Priol, T.; Petit, J.-F.; Sciare, J.

    2016-03-01

    Gaining knowledge on the process of particle resuspension from urban paved roads is of particular importance considering the increasing relevance of this source in urban air quality management and the lack of basic information on emission factors and source contributions. In this study we performed extensive field measurements for the quantification of the emission factors from different types of road in the city of Paris, and investigated the causes of their variability and the contributions to the ambient air PM10 observed across one year at one traffic monitoring site in the ring road of Paris. Results show agreement between lower road dust loadings (RD10: 0.7-2.2 mg m-2) and emission factors (5.4-9.0 mg vehicle-1 km-1) at inner-roads of Paris, compared to the ring road (2.4 mg m-2 and 17 mg vehicle-1 km-1, respectively), where the two parameters are estimated independently. The higher values in the ring road were likely caused by the poor state of pavement and higher share of heavy duty vehicles. Road wear, brake wear and a carbonaceous source, were almost equally responsible for 96% of RD10. At the traffic monitoring site located at the ring road (220,000 vehicle/day), the contributions of road dust emissions were estimated by receptor modeling to be 13% of PM10 on an annual mean (6.3 μg m-3), while the sum of vehicle exhaust and wear accounted for 47% resulting in a total traffic contribution of 60% of PM10. Road salting resulted to be a minor contributor (1% of annual mean) also in winter time (2%).

  20. Factors governing particle number emissions in a waste-to-energy plant.

    PubMed

    Ozgen, Senem; Cernuschi, Stefano; Giugliano, Michele

    2015-05-01

    Particle number concentration and size distribution measurements were performed on the stack gas of a waste-to-energy plant which co-incinerates municipal solid waste, sewage sludge and clinical waste in two lines. Average total number of particles was found to be 4.0·10(5)cm(-3) and 1.9·10(5)cm(-3) for the line equipped with a wet flue gas cleaning process and a dry cleaning system, respectively. Ultrafine particles (dp<100nm) accounted for about 97% of total number concentration for both lines, whereas the nanoparticle (dp<50nm) contribution differed slightly between the lines (87% and 84%). The experimental data is explored statistically through some multivariate pattern identifying methods such as factor analysis and cluster analysis to help the interpretation of the results regarding the origin of the particles in the flue gas with the objective of determining the factors governing the particle number emissions. The higher moisture of the flue gas in the wet cleaning process was found to increase the particle number emissions on average by a factor of about 2 due to increased secondary formation of nanoparticles through nucleation of gaseous precursors such as sulfuric acid, ammonia and water. The influence of flue gas dilution and cooling monitored through the variation of the sampling conditions also confirms the potential effect of the secondary new particle formation in increasing the particle number emissions. This finding shows the importance of reporting the experimental conditions in detail to enable the comparison and interpretation of particle number emissions. Regarding the fuel characteristics no difference was observed in terms of particle number concentration and size distributions between the clinical waste feed and the municipal solid waste co-incineration with sludge.

  1. Estimation of road traffic emission factors from a long term tracer study

    NASA Astrophysics Data System (ADS)

    Belalcazar, Luis Carlos; Fuhrer, Oliver; Ho, Minh Dung; Zarate, Erika; Clappier, Alain

    2009-12-01

    Road traffic emissions, one of the largest source categories in megacity inventories, are highly uncertain. It is essential to develop methodologies to reduce these uncertainties to manage air quality more effectively. In this paper, we propose a methodology to estimate road traffic emission factors (EFs) from a tracer experiment and from roadside pollutants measurements. We emitted continuously during about 300 non-consecutive hours a passive tracer from a finite line source placed on one site of an urban street. At the same time, we measured continuously the resulting tracer concentrations at the other side of the street with a portable on-line gas chromatograph. We used n-propane contained in commercial liquid petroleum gas (LPG) as a passive tracer. Propane offers several advantages to traditional tracers (SF6, N2O, CFCs): low price, easily available, non-reactive, negligible global warming potential, and easy to detect with commercial on-line gas chromatographs. The tracer experiment was carried out from January to March 2007 in a busy street of Ho Chi Minh City (Vietnam). Traffic volume, weather information and pollutant concentrations were also measured at the measurement site. We used the results of the tracer experiment to calculate the dilution factors and afterwards we used these dilution factors, the traffic counts and the pollutant concentrations to estimate the EFs. The proposed method assumes that the finite emission line represents the emission produced by traffic in the full area of the street and therefore there is an error associated to this assumption. We use the Computational Fluids Dynamics (CFD) model MISKAM to calculate this error and to correct the HCMC EFs. EFs for 15 volatile organic compounds (VOCs) and NO are reported here. A comparison with available studies reveals that most of the EFs estimated here are within the range of EFs reported in other studies.

  2. [An investigation of the CH4 and N2O emission factors of light-duty gasoline vehicles].

    PubMed

    He, Li-qiang; Song, Jing-hao; Hu, Jing-nan; Xie, Shu-xia; Zu, Lei

    2014-12-01

    In China, most of the studies of vehicular greenhouse gas (GHG) emissions have been focused on CO2 emissions. The investigation of non-CO2 GHGs, e.g. CH4 and N2O, are mainly carried out based on models developed in Europe and the US, and there are few vehicle emission tests for CH4 and N2O. In this study, 22 light-duty gasoline vehicles (LDGVs) were selected for tailpipe CH4 and N2O tests using chassis dynamometer, and their emission factors were obtained based on the NEDC driving cycle. The results showed that the CH4 emission factors of China I to China IV LDGVs were 0.048 g x km(-1), 0.048 g x km(-1), 0.038 g x km(-1) and 0.028 g x km(-1), respectively. For N2O, the emission factors of China I to China IV were 0.045 g x km(-1), 0.039 g x km(-1), 0.026 g x km(-1) and 0.021 g x km(-1), respectively. In the GHGs emissions (in terms of CO2 Eq.) per LDGV, the percentage of CH4 and N2O emissions decreased gradually with tightening of emission standards. The contribution of CH4 emissions was lower than 0.5% in the total emissions, and N2O share rate was between 3.03% and 6.35%. Therefore, tightening emission standards can effectively reduce the CH4 and N2O emissions, to mitigate the greenhouse effects caused by vehicle emissions.

  3. On-road measurement of gas and particle phase pollutant emission factors for individual heavy-duty diesel trucks.

    PubMed

    Dallmann, Timothy R; DeMartini, Steven J; Kirchstetter, Thomas W; Herndon, Scott C; Onasch, Timothy B; Wood, Ezra C; Harley, Robert A

    2012-08-01

    Pollutant concentrations in the exhaust plumes of individual diesel trucks were measured at high time resolution in a highway tunnel in Oakland, CA, during July 2010. Emission factors for individual trucks were calculated using a carbon balance method, in which pollutants measured in each exhaust plume were normalized to measured concentrations of carbon dioxide. Pollutants considered here include nitric oxide, nitrogen dioxide (NO(2)), carbon monoxide, formaldehyde, ethene, and black carbon (BC), as well as optical properties of emitted particles. Fleet-average emission factors for oxides of nitrogen (NO(x)) and BC respectively decreased 30 ± 6 and 37 ± 10% relative to levels measured at the same location in 2006, whereas a 34 ± 18% increase in the average NO(2) emission factor was observed. Emissions distributions for all species were skewed with a small fraction of trucks contributing disproportionately to total emissions. For example, the dirtiest 10% of trucks emitted half of total NO(2) and BC emissions. Emission rates for NO(2) were found to be anticorrelated with all other species considered here, likely due to the use of catalyzed diesel particle filters to help control exhaust emissions. Absorption and scattering cross-section emission factors were used to calculate the aerosol single scattering albedo (SSA, at 532 nm) for individual truck exhaust plumes, which averaged 0.14 ± 0.03. PMID:22799607

  4. Field measurement of greenhouse gas emission rates and development of emission factors for wastewater treatment. Final report, September 1994-March 1997

    SciTech Connect

    Eklund, B.; LaCosse, J.

    1997-09-01

    The report gives results of field testing to develop more reliable greenhouse gas (GHG) emission estimates for Wastewater treatment (WWT) lagoons. Field tests of emissions were conducted for WWT lagoons that use anaerobic processes to treat large volumes of wastewater with large biological oxygen demand (BOD) loadings. Air emissions and wastewater were measured at anaerobic lagoons at three meat processing plants and two publicly owned treatment works. The overall emission rates of CH4, carbon dioxide, carbon monoxide, nitrous oxide, ammonia (NH3), and chlorofluorocarbons were measured from each source using an open-path monitoring approach. The emitted compounds were identified and quantified by Fourier-Transform Infrared spectroscopy. Emission factors were developed for CH4 and NH3 as a function of the plant production rate, wastewater parameters (e.g., influent BOD and chemical oxygen demand (COD) loadings), and WWT system performance (e.g., BOD and COD removal rates).

  5. Field Derived Emission Factors For Formaldehyde and other Volatile Organic Compounds in FEMA Temporary Housing Units

    SciTech Connect

    Parthasarathy, Srinandini; Maddalena, Randy L.; Russell, Marion L.; Apte, Michael G.

    2010-10-01

    Sixteen previously occupied temporary housing units (THUs) were studied to assess emissions of volatile organic compounds. The whole trailer emission factors wereevaluated for 36 VOCs including formaldehyde. Indoor sampling was carried out in the THUs located in Purvis staging yard in Mississippi, USA. Indoor temperature andrelative humidity (RH) were also measured in all the trailers during sampling. Indoor temperatures were varied (increased or decreased) in a selection of THUs using theheating, ventilation and air conditioning (HVAC) systems. Indoor temperatures during sampling ranged from 14o C to 33o C, and relative humidity (RH) varied between 35percentand 74percent. Ventilation rates were increased in some trailers using bathroom fans and vents during some of the sampling events. Ventilation rates measured during some aselection of sampling events varied from 0.14 to 4.3 h-1. Steady state indoor formaldehyde concentrations ranged from 10 mu g-m-3 to 1000 mu g-m-3. The formaldehyde concentrations in the trailers were of toxicological significance. The effects of temperature, humidity and ventilation rates were also studied. A linearregression model was built using log of percentage relative humidity, inverse of temperature (in K-1), and inverse log ACH as continuous independent variables, trailermanufacturer as a categorical independent variable, and log of the chemical emission factors as the dependent variable. The coefficients of inverse temperature, log relativehumidity, log inverse ACH with log emission factor were found to be statistically significant for all the samples at the 95percent confidence level. The regression model wasfound to explain about 84percent of the variation in the dependent variable. Most VOC concentrations measured indoors in the Purvis THUs were mostly found to be belowvalues reported in earlier studies by Maddalena et al.,1,2 Hodgson et al.,3 and Hippelein4. Emissions of TMPB-DIB (a plasticizer found in vinyl products) were found

  6. Emission factors for ammonia and nitrous oxide emissions following immediate manure incorporation on two contrasting soil types

    NASA Astrophysics Data System (ADS)

    Webb, J.; Thorman, R. E.; Fernanda-Aller, M.; Jackson, D. R.

    2014-01-01

    We carried out four replicated field experiments to measure the impacts of immediate incorporation of solid manures on emissions of ammonia (NH3) and nitrous oxide (N2O). Four manures: cattle farmyard manure (FYM); pig FYM; layer manure and broiler manure were applied to the soil surface or immediately incorporated by mouldboard plough, disc or tine. Two of the experiments were carried out on a clay soil and two on a sandy soil to find out whether soil type interacted with incorporation technique to influence emissions of NH3 or N2O. Ammonia emissions were measured for 1 or 2 weeks while N2O emissions were measured for 60 days in one experiment and for a complete year in the other three experiments. Immediate incorporation by plough reduced NH3 emissions by c. 90% and by c. 60% by disc and tine (P < 0.001). There was no effect of soil type on NH3 abatement efficiency by plough or tine but the disc was less effective on the coarse sandy soil. Cross-site analysis indicated no effect of incorporation by disc or tine on emissions of N2O-N after 60 days but incorporation by plough increased direct emissions of N2O-N compared with surface application of manure (P < 0.001). Direct emissions of N2O-N, at c. 0.67% of total N applied, were substantially greater at the coarse-textured site than at the heavy clay site (0.04% of total N applied; P < 0.001). The impact of incorporation on total annual direct emissions of N2O-N differed in the three experiments where emissions were measured for a full year. There was no effect of incorporation on N2O-N emissions in the first experiment on the clay soil, and in the second experiment at this site incorporation by plough or disc, but not tine, reduced direct emissions of N2O (P = 0.006). However on the sandy soil direct emissions of N2O-N were increased when manures were incorporated by plough (P = 0.002) but not when incorporated by disc or tine. These results confirm that immediate incorporation of solid manures by plough is the

  7. Field Measurements of Gasoline Direct Injection Emission Factors: Spatial and Seasonal Variability.

    PubMed

    Zimmerman, Naomi; Wang, Jonathan M; Jeong, Cheol-Heon; Ramos, Manuel; Hilker, Nathan; Healy, Robert M; Sabaliauskas, Kelly; Wallace, James S; Evans, Greg J

    2016-02-16

    Four field campaigns were conducted between February 2014 and January 2015 to measure emissions from light-duty gasoline direct injection (GDI) vehicles (2013 Ford Focus) in an urban near-road environment in Toronto, Canada. Measurements of CO2, CO, NOx, black carbon (BC), benzene, toluene, ethylbenzene-xylenes (BTEX), and size-resolved particle number (PN) were recorded 15 m from the roadway and converted to fuel-based emission factors (EFs). Other than for NOx and CO, the GDI engine had elevated emissions compared to the Toronto fleet, with BC EFs in the 73rd percentile, BTEX EFs in the 80-90th percentile, and PN EFs in the 75th percentile during wintertime measurements. Additionally, for three campaigns, a second platform for measuring PN and CO2 was placed 1.5-3 m from the roadway to quantify changes in PN with distance from point of emission. GDI vehicle PN EFs were found to increase by up to 240% with increasing distance from the roadway, predominantly due to an increasing fraction of sub-40 nm particles. PN and BC EFs from the same engine technology were also measured in the laboratory. BC EFs agreed within 20% between the laboratory and real-world measurements; however, laboratory PN EFs were an order of magnitude lower due to exhaust conditioning. PMID:26794244

  8. Field Measurements of Gasoline Direct Injection Emission Factors: Spatial and Seasonal Variability.

    PubMed

    Zimmerman, Naomi; Wang, Jonathan M; Jeong, Cheol-Heon; Ramos, Manuel; Hilker, Nathan; Healy, Robert M; Sabaliauskas, Kelly; Wallace, James S; Evans, Greg J

    2016-02-16

    Four field campaigns were conducted between February 2014 and January 2015 to measure emissions from light-duty gasoline direct injection (GDI) vehicles (2013 Ford Focus) in an urban near-road environment in Toronto, Canada. Measurements of CO2, CO, NOx, black carbon (BC), benzene, toluene, ethylbenzene-xylenes (BTEX), and size-resolved particle number (PN) were recorded 15 m from the roadway and converted to fuel-based emission factors (EFs). Other than for NOx and CO, the GDI engine had elevated emissions compared to the Toronto fleet, with BC EFs in the 73rd percentile, BTEX EFs in the 80-90th percentile, and PN EFs in the 75th percentile during wintertime measurements. Additionally, for three campaigns, a second platform for measuring PN and CO2 was placed 1.5-3 m from the roadway to quantify changes in PN with distance from point of emission. GDI vehicle PN EFs were found to increase by up to 240% with increasing distance from the roadway, predominantly due to an increasing fraction of sub-40 nm particles. PN and BC EFs from the same engine technology were also measured in the laboratory. BC EFs agreed within 20% between the laboratory and real-world measurements; however, laboratory PN EFs were an order of magnitude lower due to exhaust conditioning.

  9. Emission factors and real-time optical properties of particles emitted from traditional wood burning cookstoves.

    PubMed

    Roden, Christoph A; Bond, Tami C; Conway, Stuart; Pinel, Anibal Benjamin Osorto

    2006-11-01

    It is estimated that the combustion of biofuel generates 20% of all carbonaceous aerosols, yet these particles are studied less than those of other common sources. We designed and built a portable battery-operated emission-sampling cart to measure the real-time optical properties and other emission characteristics of biofuel cookstoves. In a field study in Honduras, we measured emission factors averaging 8.5 g/kg, higher than those found in previous laboratory studies. Strong flaming events emitted very dark particles with the optical properties of black particles. The elemental carbon to total carbon ratios ranged from 0.07 to 0.64, confirming that high elemental carbon fractions can be emitted from biofuel combustion and may not be used to distinguish fossil-fuel from biofuel sources when cooking is the dominant usage. Absorption Angstrom exponents, representing the dependence of absorption on wavelength, ranged from 1 (black) to 5 (yellow). Strongly absorbing particles with absorption inversely dependent on wavelength were emitted separately from particles with weak absorption and strong wavelength dependence; the latter probably contained conjugated aromatic compounds. Because combustion occurs in distinct phases, different types of carbonaceous aerosols from biofuel combustion are externally mixed at emission and may have different atmospheric fates.

  10. Emission factors of polycyclic aromatic hydrocarbons from domestic coal combustion in China.

    PubMed

    Geng, Chunmei; Chen, Jianhua; Yang, Xiaoyang; Ren, Lihong; Yin, Baohui; Liu, Xiaoyu; Bai, Zhipeng

    2014-01-01

    Domestic coal stove is widely used in China, especially for countryside during heating period of winter, and polycyclic aromatic hydrocarbons (PAHs) are important in flue gas of the stove. By using dilution tunnel system, samples of both gaseous and particulate phases from domestic coal combustion were collected and 18 PAH species were analyzed by GC-MS. The average emission factors of total 18 PAH species was 171.73 mg/kg, ranging from 140.75 to 229.11 mg/kg for bituminous coals, while was 93.98 mg/kg, ranging from 58.48 to 129.47 mg/kg for anthracite coals. PAHs in gaseous phases occupied 95% of the total of PAHs emission of coal combustion. In particulate phase, 3-ring and 4-ring PAHs were the main components, accounting for 80% of the total particulate PAHs. The total toxicity potency evaluated by benzo[a]pyrene-equivalent carcinogenic power, sum of 7 carcinogenic PAH components and 2,3,7,8-tetrachlorodibenzodioxin had a similar tendency. And as a result, the toxic potential of bituminous coal was higher than that of anthracite coal. Efficient emission control should be conducted to reduce PAH emissions in order to protect ecosystem and human health.

  11. Fire environment effects on particulate matter emission factors in southeastern U.S. pine-grasslands

    NASA Astrophysics Data System (ADS)

    Robertson, Kevin M.; Hsieh, Yuch P.; Bugna, Glynnis C.

    2014-12-01

    Particulate matter (PM) emission factors (EFPM), which predict particulate emissions per biomass consumed, have a strong influence on event-based and regional PM emission estimates and inventories. PM < 2.5 μm aerodynamic diameter (PM2.5), regulated for its impacts to human health and visibility, is of special concern. Although wildland fires vary widely in their fuel conditions, meteorology, and fire behavior which might influence combustion reactions, the EFPM2.5 component of emission estimates is typically a constant for the region or general fuel type being assessed. The goal of this study was to use structural equation modeling (SEM) to identify and measure effects of fire environment variables on EFPM2.5 in U.S. pine-grasslands, which contribute disproportionately to total U.S. PM2.5 emissions. A hypothetical model was developed from past literature and tested using 41 prescribed burns in northern Florida and southern Georgia, USA with varying years since previous fire, season of burn, and fire direction of spread. Measurements focused on EFPM2.5 from flaming combustion, although a subset of data considered MCE and smoldering combustion. The final SEM after adjustment showed EFPM2.5 to be higher in burns conducted at higher ambient temperatures, corresponding to later dates during the period from winter to summer and increases in live herbaceous vegetation and ambient humidity, but not total fine fuel moisture content. Percentage of fine fuel composed of pine needles had the strongest positive effect on EFPM2.5, suggesting that pine timber stand volume may significantly influence PM2.5 emissions. Also, percentage of fine fuel composed of grass showed a negative effect on EFPM2.5, consistent with past studies. Results of the study suggest that timber thinning and frequent prescribed fire minimize EFPM2.5 and total PM2.5 emissions on a per burn basis, and that further development of PM emission models should consider adjusting EFPM2.5 as a function of common

  12. [Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

    PubMed

    Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

    2016-02-15

    Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower.

  13. Emission factors for fugitive dust from bulldozers working on a coal pile.

    PubMed

    Mueller, Stephen F; Mallard, Jonathan W; Mao, Qi; Shaw, Stephanie L

    2015-01-01

    A study of a Powder River Basin (PRB) coal pile found that fugitive emissions from natural and human activity each produced similar levels of downwind fine + coarse (i.e., smaller than 10 µm, or PM10) particle mass concentrations. Natural impacts were statistically removed from downwind measurements to estimate emission factor Ev for bulldozers working on the pile. The Ev determined here was similar in magnitude to emission factors (EFs) computed using a U.S. Environmental Protection Agency (EPA) formulation for unpaved surfaces at industrial sites, even though the latter was not based on data for coal piles. EF formulations from this study and those in the EPA guidance yield values of similar magnitude but differ in the variables used to compute Ev variations. EPA studies included effects of surface silt fraction and vehicle weight, while the present study captured the influence of coal moisture. Our data indicate that the relationship between PRB coal fugitive dust Ev (expressed as mass of PM10 emitted per minute of bulldozer operation) and coal moisture content Mc (in percent) at the study site is best expressed as Ev =10(f(Mc())) where f(Mc) is a function of moisture. This function was determined by statistical regression between log10(Ev) and Mc where both Ev and Mc are expressed as daily averages of observations based on 289 hours sampled during 44 days from late June through mid-November of 2012. A methodology is described that estimates Mc based on available meteorological data (precipitation amount and solar radiation flux). An example is given of computed variations in daily Ev for an entire year. This illustrates the sensitivity of the daily average particulate EF to meteorological variability at one location. Finally, a method is suggested for combining the moisture-sensitive formulation for Ev with the EPA formulation to accommodate a larger number of independent variables that influence fugitive emissions.

  14. [Mercury Distribution Characteristics and Atmospheric Mercury Emission Factors of Typical Waste Incineration Plants in Chongqing].

    PubMed

    Duan, Zhen-ya; Su, Hai-tao; Wang, Feng-yang; Zhang, Lei; Wang, Shu-xiao; Yu, Bin

    2016-02-15

    Waste incineration is one of the important atmospheric mercury emission sources. The aim of this article is to explore the atmospheric mercury pollution level of waste incineration industry from Chongqing. This study investigated the mercury emissions from a municipal solid waste incineration plant and a medical waste incineration plant in Chongqing. The exhaust gas samples in these two incineration plants were obtained using USA EPA 30B method. The mercury concentrations in the fly ash and bottom ash samples were analyzed. The results indicated that the mercury concentrations of the municipal solid waste and medical waste incineration plant in Chongqing were (26.4 +/- 22.7) microg x m(-3) and (3.1 +/- 0.8) microg x m(-3) in exhaust gas respectively, (5279.2 +/- 798.0) microg x kg(-1) and (11,709.5 +/- 460.5) microg x kg(-1) in fly ash respectively. Besides, the distribution proportions of the mercury content from municipal solid waste and medical waste in exhaust gas, fly ash, and bottom ash were 34.0%, 65.3%, 0.7% and 32.3%, 67.5%, 0.2% respectively; The mercury removal efficiencies of municipal solid waste and medical waste incineration plants were 66.0% and 67.7% respectively. The atmospheric mercury emission factors of municipal solid waste and medical waste incineration plants were (126.7 +/- 109.0) microg x kg(-1) and (46.5 +/- 12.0) microg x kg(-1) respectively. Compared with domestic municipal solid waste incineration plants in the Pearl River Delta region, the atmospheric mercury emission factor of municipal solid waste incineration plant in Chongqing was lower. PMID:27363131

  15. Emission factors for open and domestic biomass burning for use in atmospheric models

    NASA Astrophysics Data System (ADS)

    Akagi, S. K.; Yokelson, R. J.; Wiedinmyer, C.; Alvarado, M. J.; Reid, J. S.; Karl, T.; Crounse, J. D.; Wennberg, P. O.

    2011-05-01

    Biomass burning (BB) is the second largest source of trace gases and the largest source of primary fine carbonaceous particles in the global troposphere. Many recent BB studies have provided new emission factor (EF) measurements. This is especially true for non-methane organic compounds (NMOC), which influence secondary organic aerosol (SOA) and ozone formation. New EF should improve regional to global BB emissions estimates and therefore, the input for atmospheric models. In this work we present an up-to-date, comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has cooled to ambient temperature, but not yet undergone significant photochemical processing. All EFs are converted to one standard form (g compound emitted per kg dry biomass burned) using the carbon mass balance method and they are categorized into 14 fuel or vegetation types. Biomass burning terminology is defined to promote consistency. We compile a large number of measurements of biomass consumption per unit area for important fire types and summarize several recent estimates of global biomass consumption by the major types of biomass burning. Post emission processes are discussed to provide a context for the emission factor concept within overall atmospheric chemistry and also highlight the potential for rapid changes relative to the scale of some models or remote sensing products. Recent work shows that individual biomass fires emit significantly more gas-phase NMOC than previously thought and that including additional NMOC can improve photochemical model performance. A detailed global estimate suggests that BB emits at least 400 Tg yr-1 of gas-phase NMOC, which is almost 3 times larger than most previous estimates. Selected recent results (e.g. measurements of HONO and the BB tracers HCN and CH3CN) are highlighted and key areas requiring future research are briefly discussed.

  16. 40 CFR 63.5796 - What are the organic HAP emissions factor equations in Table 1 to this subpart, and how are they...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Organic Hap Emissions Factors for Open Molding and Centrifugal Casting § 63.5796 What are the organic HAP... emissions factors. Equations are available for each open molding operation and centrifugal casting...

  17. 40 CFR 63.5796 - What are the organic HAP emissions factor equations in Table 1 to this subpart, and how are they...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Emissions Factors for Open Molding and Centrifugal Casting § 63.5796 What are the organic HAP emissions... factors. Equations are available for each open molding operation and centrifugal casting operation...

  18. Differences in satellite-derived NOx emission factors between Eurasian and North American boreal forest fires

    NASA Astrophysics Data System (ADS)

    Schreier, S. F.; Richter, A.; Schepaschenko, D.; Shvidenko, A.; Hilboll, A.; Burrows, J. P.

    2015-11-01

    Current fire emission inventories apply universal emission factors (EFs) for the calculation of NOx emissions over large biomes such as boreal forest. However, recent satellite-based studies over tropical and subtropical regions have indicated spatio-temporal variations in EFs within specific biomes. In this study, satellite measurements of tropospheric NO2 vertical columns (TVC NO2) from the GOME-2 instrument and fire radiative power (FRP) from MODIS are used for the estimation of fire emission rates (FERs) of NOx over Eurasian and North American boreal forests. The retrieval of TVC NO2 is based on a stratospheric correction using simulated stratospheric NO2 instead of applying the reference sector method, which was used in a previous study. The model approach is more suitable for boreal latitudes. TVC NO2 and FRP are spatially aggregated to a 1° × 1° horizontal resolution and temporally averaged to monthly values. The conversion of the satellite-derived tropospheric NO2 columns into production rates of NOx from fire (Pf) is based on the NO2/NOx ratio as obtained from the MACC reanalysis data set and an assumed lifetime of NOx. A global land cover map is used to define boreal forests across these two regions in order to evaluate the FERs of NOx for this biome. The FERs of NOx, which are derived from the gradients of the linear relationship between Pf and FRP, are more than 30% lower for North American than for Eurasian boreal forest fires. We speculate that these discrepancies are mainly related to the variable nitrogen content in plant tissues, which is higher in deciduous forests dominating large parts in Eurasia. In order to compare the obtained values with EFs found in the literature, the FERs are converted into EFs. The satellite-based EFs of NOx are estimated at 0.83 and 0.61 g kg-1 for Eurasian and North American boreal forests, respectively, which is in good agreement with the value found in a recent emission factor compilation. However, recent fire

  19. 40 CFR Table W - 7 of Subpart W-Default Methane Emission Factors for Natural Gas Distribution

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protected Steel 0.02 Plastic 0.001 Copper 0.03 1 Excluding customer meters. 2 Emission Factor is in units of... Line 26.131 Population Emission Factors—Below Grade Metering-Regulating station 1 Components, Gas Service 2 Below Grade M&R Station, Inlet Pressure > 300 psig 1.30 Below Grade M&R Station, Inlet...

  20. [Emission factors and PM chemical composition study of biomass burning in the Yangtze River Delta region].

    PubMed

    Tang, Xi-Bin; Huang, Cheng; Lou, Sheng-Rong; Qiao, Li-Ping; Wang, Hong-Li; Zhou, Min; Chen, Ming-hua; Chen, Chang-Hong; Wang, Qian; Li, Gui-Ling; Li, Li; Huang, Hai-Ying; Zhang, Gang-Feng

    2014-05-01

    The emission characteristics of five typical crops, including wheat straw, rice straw, oil rape straw, soybean straw and fuel wood, were investigated to explore the gas and particulates emission of typical biomass burning in Yangzi-River-Delta area. The straws were tested both by burning in stove and by burning in the farm with a self-developed measurement system as open burning sources. Both gas and fine particle pollutants were measured in this study as well as the chemical composition of fine particles. The results showed that the average emission factors of CO, NO, and PM2,5 in open farm burning were 28.7 g.kg -1, 1.2 g.kg-1 and 2.65 g kg-1 , respectively. Due to insufficient burning in the low oxygen level environment, the emission factors of stove burning were higher than those of open farm burning, which were 81.9 g kg-1, 2. 1 g.kg -1 and 8.5 gkg -1 , respectively. Oil rape straw had the highest emission factors in all tested straws samples. Carbonaceous matter, including organic carbon(OC) and element carbon(EC) , was the foremost component of PM2, 5from biomass burning. The average mass fractions of OC and EC were (38.92 +/- 13.93)% and (5.66 +/-1.54)% by open farm burning and (26.37 +/- 10. 14)% and (18.97 +/- 10.76)% by stove burning. Water soluble ions such as Cl-and K+ had a large contribution. The average mass fractions of CI- and K+ were (13.27 +/-6. 82)% and (12.41 +/- 3.02)% by open farm burning, and were (16.25 +/- 9.34)% and (13.62 +/- 7.91)% by stove burning. The K +/OC values of particles from wheat straw, rice straw, oil rape straw and soybean straw by open farm burning were 0. 30, 0. 52, 0. 49 and 0. 15, respectively, which can be used to evaluate the influence on the regional air quality in YRD area from biomass burning and provide direct evidence for source apportionment.

  1. Clustering-initiated factor analysis application for tissue classification in dynamic brain positron emission tomography

    PubMed Central

    Boutchko, Rostyslav; Mitra, Debasis; Baker, Suzanne L; Jagust, William J; Gullberg, Grant T

    2015-01-01

    The goal is to quantify the fraction of tissues that exhibit specific tracer binding in dynamic brain positron emission tomography (PET). It is achieved using a new method of dynamic image processing: clustering-initiated factor analysis (CIFA). Standard processing of such data relies on region of interest analysis and approximate models of the tracer kinetics and of tissue properties, which can degrade accuracy and reproducibility of the analysis. Clustering-initiated factor analysis allows accurate determination of the time–activity curves and spatial distributions for tissues that exhibit significant radiotracer concentration at any stage of the emission scan, including the arterial input function. We used this approach in the analysis of PET images obtained using 11C-Pittsburgh Compound B in which specific binding reflects the presence of β-amyloid. The fraction of the specific binding tissues determined using our approach correlated with that computed using the Logan graphical analysis. We believe that CIFA can be an accurate and convenient tool for measuring specific binding tissue concentration and for analyzing tracer kinetics from dynamic images for a variety of PET tracers. As an illustration, we show that four-factor CIFA allows extraction of two blood curves and the corresponding distributions of arterial and venous blood from PET images even with a coarse temporal resolution. PMID:25899294

  2. Toxic Volatile Organic Compounds in Environmental Tobacco Smoke:Emission Factors for Modeling Exposures of California Populations

    SciTech Connect

    Daisey, J.M.; Mahanama, K.R.R.; Hodgson, A.T.

    1994-10-01

    The primary objective of this study was to measure emission factors for selected toxic air in environmental tobacco smoke (ETS) using a room-sized environmental chamber. The emissions of 23 volatile organic compounds (VOCs), including 1,3-butadiene, three aldehydes and two vapor-phase N-nitrosarnines were determined for six commercial brands of cigarettes and reference cigarette 1R4F. The commercial brands were selected to represent 62.5% of the cigarettes smoked in California. For each brand, three cigarettes were machine smoked in the chamber. The experiments were conducted over four hours to investigate the effects of aging. Emission factors of the target compounds were also determined for sidestream smoke (SS). For almost all target compounds, the ETS emission factors were significantly higher than the corresponding SS values probably due to less favorable combustion conditions and wall losses in the SS apparatus. Where valid comparisons could be made, the ETS emission factors were generally in good agreement with the literature. Therefore, the ETS emission factors, rather than the SS values, are recommended for use in models to estimate population exposures from this source. The variabilities in the emission factors (pgkigarette) of the selected toxic air contaminants among brands, expressed as coefficients of variation, were 16 to 29%. Therefore, emissions among brands were generally similar. Differences among brands were related to the smoked lengths of the cigarettes and the masses of consumed tobacco. Mentholation and whether a cigarette was classified as light or regular did not significantly affect emissions. Aging was determined not to be a significant factor for the target compounds. There were, however, deposition losses of the less volatile compounds to chamber surfaces.

  3. Fire Radiative Power (FRP)-based Emission Factors of PM2.5, CO and NOX for Remote Sensing of Biomass Burning Emissions

    NASA Astrophysics Data System (ADS)

    Karandana Gamalathge, T. D.; Chen, L. W. A.

    2015-12-01

    Large-scale biomass burning such as forest fires represents an important and yet uncertain source of air pollutants and greenhouse gases on a global scale. Due to the highly accidental nature of forest fires, satellite remote sensing could be a promising method to develop regional and global fire emission inventories on a real-time basis. Reliable fire radiative power (FRP)-based fuel consumption and emission factors are critical in this approach. In an attempt to obtain the information, laboratory combustion experiments were conducted to simultaneously monitor FRP, fuel consumption, and emissions of fine particulate matter (PM2.5), carbon monoxide (CO), and reactive nitrogen oxides (NO and NO2). FRP were quantified using temperature-resolved values from a thermal imager instead of conventionally used average temperature, as the former provides more realistic estimates. For dry Ponderosa pine branches, a common fuel in the Sierra Nevada, a strong correlation (r2 ~ 0.8) between FRP and the mass reduction rate (MRR) was found. This led to a radiative energy yield (REY) of 8.5 ± 1.2 MJ/kg, assuming blackbody radiation and a flame emissivity of 0.5. Mass-based emission factors were determined with the carbon balance approach. Considering the ratio of mass-based emission factors and the REY, FRP-based emission factors: PM2.5: 11 g/MJ, CO: 8.0 g/MJ, NO: 0.33 g/MJ, and NO2: 0.07 g/MJ were quantified. The application of this approach to other fuel types and uncertainties in the measurements will be discussed.

  4. Atmospheric pollutant emission factors from open burning of agricultural and forest biomass by wind tunnel simulations. Volume 1. Final report

    SciTech Connect

    Jenkins, B.M.; Turn, S.Q.; Williams, R.B.; Goronea, M.; Abd-el-Fattah, H.

    1996-04-01

    Atmospheric pollutant emission factors were determined by wind tunnel simulations of spreading and pile fires for 8 different types of fuel including barley, rice and wheat straw, corn stover, almond and walnut tree prunings, and Douglas fir and Ponderosa pine slash. Cereal straws and stover were burned in fires spreading against an impressed wind, pile burns in wood fuels were naturally ventilaled through the side doors. Emission factors were determined for each fuel for CO, NO, NOx, SO2, total hydrocarbons, methane, nonmethane hydrocarbons, total sulfur, CO2, particulate matter, volatile organic matter (VOC), and polycyclic aromatic hydrocarbons (PAH). Elemental compositions of particulate matter were determined by size category. Bulk aerosol absorption coefficients were determined from light transmission measurements through filter samples. Emission rates were correlated against burning conditions and fuel compositions. Factor affecting the burning rates and emission factors included inlet air temperature, loading rate, and wind speed.

  5. 40 CFR 63.5890 - How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... emissions factor to demonstrate compliance for continuous lamination/casting operations? 63.5890 Section 63... continuous lamination/casting operations? (a) Compliant line option. Use Equation 1 of this section to... compliance. Continuous Compliance Requirements...

  6. 40 CFR 63.5890 - How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... emissions factor to demonstrate compliance for continuous lamination/casting operations? 63.5890 Section 63... continuous lamination/casting operations? (a) Compliant line option. Use Equation 1 of this section to... compliance. Continuous Compliance Requirements...

  7. 40 CFR 63.5796 - What are the organic HAP emissions factor equations in Table 1 to this subpart, and how are they...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... emissions factors to demonstrate compliance provided your site-specific organic HAP emissions factors are... 40 Protection of Environment 12 2010-07-01 2010-07-01 true What are the organic HAP emissions factor equations in Table 1 to this subpart, and how are they used in this subpart? 63.5796 Section...

  8. Updated greenhouse gas and criteria air pollutant emission factors and their probability distribution functions for electricity generating units

    SciTech Connect

    Cai, H.; Wang, M.; Elgowainy, A.; Han, J.

    2012-07-06

    Greenhouse gas (CO{sub 2}, CH{sub 4} and N{sub 2}O, hereinafter GHG) and criteria air pollutant (CO, NO{sub x}, VOC, PM{sub 10}, PM{sub 2.5} and SO{sub x}, hereinafter CAP) emission factors for various types of power plants burning various fuels with different technologies are important upstream parameters for estimating life-cycle emissions associated with alternative vehicle/fuel systems in the transportation sector, especially electric vehicles. The emission factors are typically expressed in grams of GHG or CAP per kWh of electricity generated by a specific power generation technology. This document describes our approach for updating and expanding GHG and CAP emission factors in the GREET (Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation) model developed at Argonne National Laboratory (see Wang 1999 and the GREET website at http://greet.es.anl.gov/main) for various power generation technologies. These GHG and CAP emissions are used to estimate the impact of electricity use by stationary and transportation applications on their fuel-cycle emissions. The electricity generation mixes and the fuel shares attributable to various combustion technologies at the national, regional and state levels are also updated in this document. The energy conversion efficiencies of electric generating units (EGUs) by fuel type and combustion technology are calculated on the basis of the lower heating values of each fuel, to be consistent with the basis used in GREET for transportation fuels. On the basis of the updated GHG and CAP emission factors and energy efficiencies of EGUs, the probability distribution functions (PDFs), which are functions that describe the relative likelihood for the emission factors and energy efficiencies as random variables to take on a given value by the integral of their own probability distributions, are updated using best-fit statistical curves to characterize the uncertainties associated with GHG and CAP emissions in life

  9. Methane dynamics in a montane fen: Factors controlling production, accumulation and emissions

    NASA Astrophysics Data System (ADS)

    Mwakanyamale, K. E.; Yeung, H.; Strack, M.

    2014-12-01

    Characterization of methane dynamics in peatlands is essential to improve understanding of peatlands contribution to carbon balance and interaction with climate. Of the two peatland types, natural fens are known to be a larger contributor of methane emissions to the atmosphere than natural bogs. This study uses geophysical methods integrated with in-situ direct measurements and chamber fluxes to improve understanding of temporal and spatial variation in methane production, accumulation and emissions from natural montane fen in Alberta Canada. Meteorological data and peat cores (~150 cm) were collected to study factors affecting methane production, accumulation and emissions from the Sibbald Research Wetland, a montane fen in the Rocky Mountains in southern Alberta. Our results show a direct correlation between methane accumulation and degree of peat humification, substrate quality and porosity. Changes in temperature, pressure and water table position were shown to relate to ebullition events, with the highest number of ebullition events occurring from late August to early November. The geophysical results indicate a small spatial variation in free phase biogenic gas accumulation within the studied area. Diffusive methane fluxes were correlated to plant productivity on both daily and seasonal time scales with patterns varying between plots dominated by Juncus sp. and Carex spp. These results highlight the interacting ecological and physical controls on peatland methane dynamics.

  10. Interpretation of the field enhancement factor for electron emission from carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Smith, R. C.; Silva, S. R. P.

    2009-07-01

    The local electric fields in the vicinity of the tips of metallic nanotubes are calculated. The variation in the field enhancement factor as a function of internanotube separation, anode-substrate separation, and height and radius of the nanotube is reported. Calculations show that the field induced electron emission current, based on the Fowler-Nordheim theory, is reduced when the intertube separation is less than twice the height of the nanotube. The location of the anode plane is shown to be important when the anode-substrate separation is less than three times the height of the nanotube. The results also predict that the macroscopic threshold field for electron emission should decrease as the anode-substrate separation D decreases. For separations greater than three times the height of the nanotube, the threshold field becomes constant and independent of anode-cathode geometry. Conversely, the manner in which applied electric field is defined is crucial if the results are be understood better. Experimental field emission measurements made on an isolated carbon nanotube confirms the need for a new interpretation of the electric field around stand alone point emitters.

  11. Emission Factors of Nitrous Oxide by Organic Manure Fertilizers in Japanese Upland Fields

    NASA Astrophysics Data System (ADS)

    Sudo, S.

    2011-12-01

    Preliminary data of field experiments which were conducted to estimate emission factors of nitrous oxide by organic manure fertilizers in 10 Japan-wide experiment sites, 2010 was reported. We compared nitrous oxide emission from urea as chemical fertilizers and cow manure as organic applications, in 1o Japanese prefectures of Yamagata, Fukushima, Ibaraki, Aichi, Shiga, Tokushima, Nagasaki, Kumamoto and Kagoshima. Same amounts of nitrogen were applied in organic and inorganic fertilizers in each field. In each site, 3 replication plots were organized in randomized block design with zero-nitrogen application plots. N2O gas fluxes were measured every one week or more during cultivation seasons. We also measured several soil physical and chemical parameters of inorganic nitrogen species, soil moisture contents or WFPS (Water Filled Pore Space), soil temperatures, bulk densities etc. Gas fluxes ware measured by automated Shimadzu GC-2014 ECD gas chromatograph. Soil moistures were measured by Camplel's Hydrosense in each site. Vegetation of conducting fields were cabbage in 7 fields, wheat in 1, pear orchard and onion in 1. Microorganisms' abundance was also considered to clarify N2O emission processes by the PCR-DGGE method.

  12. Particle number concentration near road traffic in Amsterdam (the Netherlands): Comparison of standard and real-world emission factors

    NASA Astrophysics Data System (ADS)

    Keuken, M. P.; Moerman, M.; Voogt, M.; Zandveld, P.; Verhagen, H.; Stelwagen, U.; Jonge de, D.

    2016-05-01

    In this study, NOx and particle number concentration (PNC) at an urban background and a traffic location were measured in the city of Amsterdam (the Netherlands). Modelled and measured contributions to NOx and PNC at the traffic location were used to derive real-world PN emission factors for average urban road traffic. The results for NOx were applied to validate our approach. The real-world PN emission factors (#.km-1) were 2.9E+14 (urban road) and 3E+14 (motorway). These values were at least a factor eight higher than dynamometer-based PN emission factors from COPERT 4 and HBEFA databases. The real-world PN emission factors were used to model the contribution to PNC near road traffic in 2014. This was two to three times higher than the PNC urban background along urban roads over 20,000 vehicles per day and near motorways. The discrepancy between dynamometer-based and real-world emission factors demonstrates the need for more PNC observations to assess actual PN emissions from road traffic.

  13. Intermediate Volatility Organic Compound Emissions from On-Road Diesel Vehicles: Chemical Composition, Emission Factors, and Estimated Secondary Organic Aerosol Production.

    PubMed

    Zhao, Yunliang; Nguyen, Ngoc T; Presto, Albert A; Hennigan, Christopher J; May, Andrew A; Robinson, Allen L

    2015-10-01

    Emissions of intermediate-volatility organic compounds (IVOCs) from five on-road diesel vehicles and one off-road diesel engine were characterized during dynamometer testing. The testing evaluated the effects of driving cycles, fuel composition and exhaust aftertreatment devices. On average, more than 90% of the IVOC emissions were not identified on a molecular basis, instead appearing as an unresolved complex mixture (UCM) during gas-chromatography mass-spectrometry analysis. Fuel-based emissions factors (EFs) of total IVOCs (speciated + unspeciated) depend strongly on aftertreatment technology and driving cycle. Total-IVOC emissions from vehicles equipped with catalyzed diesel particulate filters (DPF) are substantially lower (factor of 7 to 28, depending on driving cycle) than from vehicles without any exhaust aftertreatment. Total-IVOC emissions from creep and idle operations are substantially higher than emissions from high-speed operations. Although the magnitude of the total-IVOC emissions can vary widely, there is little variation in the IVOC composition across the set of tests. The new emissions data are combined with published yield data to investigate secondary organic aerosol (SOA) formation. SOA production from unspeciated IVOCs is estimated using surrogate compounds, which are assigned based on gas-chromatograph retention time and mass spectral signature of the IVOC UCM. IVOCs contribute the vast majority of the SOA formed from exhaust from on-road diesel vehicles. The estimated SOA production is greater than predictions by previous studies and substantially higher than primary organic aerosol. Catalyzed DPFs substantially reduce SOA formation potential of diesel exhaust, except at low speed operations.

  14. Intermediate Volatility Organic Compound Emissions from On-Road Diesel Vehicles: Chemical Composition, Emission Factors, and Estimated Secondary Organic Aerosol Production.

    PubMed

    Zhao, Yunliang; Nguyen, Ngoc T; Presto, Albert A; Hennigan, Christopher J; May, Andrew A; Robinson, Allen L

    2015-10-01

    Emissions of intermediate-volatility organic compounds (IVOCs) from five on-road diesel vehicles and one off-road diesel engine were characterized during dynamometer testing. The testing evaluated the effects of driving cycles, fuel composition and exhaust aftertreatment devices. On average, more than 90% of the IVOC emissions were not identified on a molecular basis, instead appearing as an unresolved complex mixture (UCM) during gas-chromatography mass-spectrometry analysis. Fuel-based emissions factors (EFs) of total IVOCs (speciated + unspeciated) depend strongly on aftertreatment technology and driving cycle. Total-IVOC emissions from vehicles equipped with catalyzed diesel particulate filters (DPF) are substantially lower (factor of 7 to 28, depending on driving cycle) than from vehicles without any exhaust aftertreatment. Total-IVOC emissions from creep and idle operations are substantially higher than emissions from high-speed operations. Although the magnitude of the total-IVOC emissions can vary widely, there is little variation in the IVOC composition across the set of tests. The new emissions data are combined with published yield data to investigate secondary organic aerosol (SOA) formation. SOA production from unspeciated IVOCs is estimated using surrogate compounds, which are assigned based on gas-chromatograph retention time and mass spectral signature of the IVOC UCM. IVOCs contribute the vast majority of the SOA formed from exhaust from on-road diesel vehicles. The estimated SOA production is greater than predictions by previous studies and substantially higher than primary organic aerosol. Catalyzed DPFs substantially reduce SOA formation potential of diesel exhaust, except at low speed operations. PMID:26322746

  15. The Covering Factor of Warm Dust in Weak Emission-line Active Galactic Nuclei

    NASA Astrophysics Data System (ADS)

    Zhang, Xudong; Liu, Yuan

    2016-10-01

    Weak emission-line active galactic nuclei (WLAGNs) are radio-quiet active galactic nuclei (AGNs) that have nearly featureless optical spectra. We investigate the ultraviolet to mid-infrared spectral energy distributions of 73 WLAGNs (0.4 < z < 3) and find that most of them are similar to normal AGNs. We also calculate the covering factor of warm dust of these 73 WLAGNs. No significant difference is indicated by a KS test between the covering factor of WLAGNs and normal AGNs in the common range of bolometric luminosity. The implication for several models of WLAGNs is discussed. The super-Eddington accretion is unlikely to be the dominant reason for the featureless spectrum of a WLAGN. The present results are still consistent with the evolution scenario, i.e., WLAGNs are in a special stage of AGNs.

  16. DEVELOPMENT OF A MICROSCALE EMISSION FACTOR MODEL FOR PARTICULATE MATTER (MICROFACPM) FOR PREDICTING REAL-TIME MOTOR VEHICLE EMISSIONS

    EPA Science Inventory

    The United States Environmental Protection Agency's National Exposure Research Laboratory has initiated a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source t...

  17. DEVELOPMENT OF A MICROSCALE EMISSION FACTOR MODEL FOR PARTICULATE MATTER (MICROFACPM) FOR PREDICTING REAL TIME MOTOR VEHICLE EMISSIONS

    EPA Science Inventory

    Health risk evaluation needs precise measurement and modeling of human exposures in microenvironments to support review of current air quality standards. The particulate matter emissions from motor vehicles are a major component of human exposures in urban microenvironments. Cu...

  18. DEVELOPMENT OF A MICROSCALE EMISSION FACTOR MODEL FOR CO (MICROFACCO) FOR PREDICTING REAL-TIME VEHICLE EMISSIONS

    EPA Science Inventory

    The United States Environmental Protection Agency's National Exposure Research Laboratory has initiated a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project goal is to develop improved methods for modeling the source t...

  19. DEVELOPMENT OF A MICROSCALE EMISSION FACTOR MODEL FOR PARTICULATE MATTER (MICROFACPM) FOR PREDICTING REAL-TIME MOTOR VEHICLE EMISSIONS

    EPA Science Inventory

    The United States Environmental Protection Agency's National Exposure Research Laboratory is pursuing a project to improve the methodology for modeling human exposure to motor vehicle emissions. The overall project is to develop improved methods for modeling the source through...

  20. X-Ray Absorption, Nuclear Infrared Emission, and Dust Covering Factors of AGNs: Testing Unification Schemes

    NASA Astrophysics Data System (ADS)

    Mateos, S.; Carrera, F. J.; Alonso-Herrero, A.; Hernán-Caballero, A.; Barcons, X.; Asensio Ramos, A.; Watson, M. G.; Blain, A.; Caccianiga, A.; Ballo, L.; Braito, V.; Ramos Almeida, C.

    2016-03-01

    We present the distributions of the geometrical covering factors of the dusty tori (f2) of active galactic nuclei (AGNs) using an X-ray selected complete sample of 227 AGNs drawn from the Bright Ultra-hard XMM-Newton Survey. The AGNs have z from 0.05 to 1.7, 2-10 keV luminosities between 1042 and 1046 erg s-1, and Compton-thin X-ray absorption. Employing data from UKIDSS, 2MASS, and the Wide-field Infrared Survey Explorer in a previous work, we determined the rest-frame 1-20 μm continuum emission from the torus, which we model here with the clumpy torus models of Nenkova et al. Optically classified type 1 and type 2 AGNs are intrinsically different, with type 2 AGNs having, on average, tori with higher f2 than type 1 AGNs. Nevertheless, ˜20% of type 1 AGNs have tori with large covering factors, while ˜23%-28% of type 2 AGNs have tori with small covering factors. Low f2 are preferred at high AGN luminosities, as postulated by simple receding torus models, although for type 2 AGNs the effect is certainly small. f2 increases with the X-ray column density, which implies that dust extinction and X-ray absorption take place in material that share an overall geometry and most likely belong to the same structure, the putative torus. Based on our results, the viewing angle, AGN luminosity, and also f2 determine the optical appearance of an AGN and control the shape of the rest-frame ˜1-20 μm nuclear continuum emission. Thus, the torus geometrical covering factor is a key ingredient of unification schemes.

  1. New model for capturing the variations of fertilizer-induced emission factors of N2O

    NASA Astrophysics Data System (ADS)

    Zhou, Feng; Shang, Ziyin; Zeng, Zhenzhong; Piao, Shilong; Ciais, Philippe; Raymond, Peter A.; Wang, Xuhui; Wang, Rong; Chen, Minpeng; Yang, Changliang; Tao, Shu; Zhao, Yue; Meng, Qian; Gao, Shuoshuo; Mao, Qi

    2015-06-01

    Accumulating evidence indicates that N2O emission factors (EFs) vary with nitrogen additions and environmental variations. Yet the impact of the latter was often ignored by previous EF determinations. We developed piecewise statistical models (PMs) to explain how the N2O EFs in agricultural soils depend upon various predictors such as climate, soil attributes, and agricultural management. The PMs are derived from a new Bayesian Recursive Regression Tree algorithm. The PMs were applied to the case of EFs from agricultural soils in China, a country where large EF spatial gradients prevail. The results indicate substantial improvements of the PMs compared with other EF determinations. First, PMs are able to reproduce a larger fraction of the variability of observed EFs for upland grain crops (84%, n = 381) and paddy rice (91%, n = 161) as well as the ratio of EFs to nitrogen application rates (73%, n = 96). The superior predictive accuracy of PMs is further confirmed by evaluating their predictions against independent EF measurements (n = 285) from outside China. Results show that the PMs calibrated using Chinese data can explain 75% of the variance. Hence, the PMs could be reliable for upscaling of N2O EFs and fluxes for regions that have a phase space of predictors similar to China. Results from the validated models also suggest that climatic factors regulate the heterogeneity of EFs in China, explaining 69% and 85% of their variations for upland grain crops and paddy rice, respectively. The corresponding N2O EFs in 2008 are 0.84 ± 0.18% (as N2O-N emissions divided by the total N input) for upland grain crops and 0.65 ± 0.14% for paddy rice, the latter being twice as large as the Intergovernmental Panel on Climate Change Tier 1 defaults. Based upon these new estimates of EFs, we infer that only 22% of current arable land could achieve a potential reduction of N2O emission of 50%.

  2. Exhaust constituent emission factors of printed circuit board pyrolysis processes and its exhaust control.

    PubMed

    Chiang, Hung-Lung; Lin, Kuo-Hsiung

    2014-01-15

    The printed circuit board (PCB) is an important part of electrical and electronic equipment, and its disposal and the recovery of useful materials from waste PCBs (WPCBs) are key issues for waste electrical and electronic equipment. Waste PCB compositions and their pyrolysis characteristics were analyzed in this study. In addition, the volatile organic compound (VOC) exhaust was controlled by an iron-impregnated alumina oxide catalyst. Results indicated that carbon and oxygen were the dominant components (hundreds mg/g) of the raw materials, and other elements such as nitrogen, bromine, and copper were several decades mg/g. Exhaust constituents of CO, H2, CH4, CO2, and NOx, were 60-115, 0.4-4.0, 1.1-10, 30-95, and 0-0.7mg/g, corresponding to temperatures ranging from 200 to 500°C. When the pyrolysis temperature was lower than 300°C, aromatics and paraffins were the major species, contributing 90% of ozone precursor VOCs, and an increase in the pyrolysis temperature corresponded to a decrease in the fraction of aromatic emission factors. Methanol, ethylacetate, acetone, dichloromethane, tetrachloromethane and acrylonitrile were the main species of oxygenated and chlorinated VOCs. The emission factors of some brominated compounds, i.e., bromoform, bromophenol, and dibromophenol, were higher at temperatures over 400°C. When VOC exhaust was flowed through the bed of Fe-impregnated Al2O3, the emission of ozone precursor VOCs could be reduced by 70-80%. PMID:24239260

  3. Variability in Light-Duty Gasoline Vehicle Emission Factors from Trip-Based Real-World Measurements.

    PubMed

    Liu, Bin; Frey, H Christopher

    2015-10-20

    Using data obtained with portable emissions measurements systems (PEMS) on multiple routes for 100 gasoline vehicles, including passenger cars (PCs), passenger trucks (PTs), and hybrid electric vehicles (HEVs), variability in tailpipe emission rates was evaluated. Tier 2 emission standards are shown to be effective in lowering NOx, CO, and HC emission rates. Although PTs are larger, heavier vehicles that consume more fuel and produce more CO2 emissions, they do not necessarily produce more emissions of regulated pollutants compared to PCs. HEVs have very low emission rates compared to tier 2 vehicles under real-world driving. Emission factors vary with cycle average speed and road type, reflecting the combined impact of traffic control and traffic congestion. Compared to the slowest average speed and most congested cycles, optimal emission rates could be 50% lower for CO2, as much as 70% lower for NOx, 40% lower for CO, and 50% lower for HC. There is very high correlation among vehicles when comparing driving cycles. This has implications for how many cycles are needed to conduct comparisons between vehicles, such as when comparing fuels or technologies. Concordance between empirical and predicted emission rates using the U.S. Environmental Protection Agency's MOVES model was also assessed.

  4. Study on influencing factors of carbon emissions from energy consumption of Shandong Province of China from 1995 to 2012.

    PubMed

    Song, Jiekun; Song, Qing; Zhang, Dong; Lu, Youyou; Luan, Long

    2014-01-01

    Carbon emissions from energy consumption of Shandong province from 1995 to 2012 are calculated. Three zero-residual decomposition models (LMDI, MRCI and Shapley value models) are introduced for decomposing carbon emissions. Based on the results, Kendall coordination coefficient method is employed for testing their compatibility, and an optimal weighted combination decomposition model is constructed for improving the objectivity of decomposition. STIRPAT model is applied to evaluate the impact of each factor on carbon emissions. The results show that, using 1995 as the base year, the cumulative effects of population, per capita GDP, energy consumption intensity, and energy consumption structure of Shandong province in 2012 are positive, while the cumulative effect of industrial structure is negative. Per capita GDP is the largest driver of the increasing carbon emissions and has a great impact on carbon emissions; energy consumption intensity is a weak driver and has certain impact on carbon emissions; population plays a weak driving role, but it has the most significant impact on carbon emissions; energy consumption structure is a weak driver of the increasing carbon emissions and has a weak impact on carbon emissions; industrial structure has played a weak inhibitory role, and its impact on carbon emissions is great.

  5. Variability in Light-Duty Gasoline Vehicle Emission Factors from Trip-Based Real-World Measurements.

    PubMed

    Liu, Bin; Frey, H Christopher

    2015-10-20

    Using data obtained with portable emissions measurements systems (PEMS) on multiple routes for 100 gasoline vehicles, including passenger cars (PCs), passenger trucks (PTs), and hybrid electric vehicles (HEVs), variability in tailpipe emission rates was evaluated. Tier 2 emission standards are shown to be effective in lowering NOx, CO, and HC emission rates. Although PTs are larger, heavier vehicles that consume more fuel and produce more CO2 emissions, they do not necessarily produce more emissions of regulated pollutants compared to PCs. HEVs have very low emission rates compared to tier 2 vehicles under real-world driving. Emission factors vary with cycle average speed and road type, reflecting the combined impact of traffic control and traffic congestion. Compared to the slowest average speed and most congested cycles, optimal emission rates could be 50% lower for CO2, as much as 70% lower for NOx, 40% lower for CO, and 50% lower for HC. There is very high correlation among vehicles when comparing driving cycles. This has implications for how many cycles are needed to conduct comparisons between vehicles, such as when comparing fuels or technologies. Concordance between empirical and predicted emission rates using the U.S. Environmental Protection Agency's MOVES model was also assessed. PMID:26401623

  6. Study on Influencing Factors of Carbon Emissions from Energy Consumption of Shandong Province of China from 1995 to 2012

    PubMed Central

    Song, Jiekun; Song, Qing; Zhang, Dong; Lu, Youyou; Luan, Long

    2014-01-01

    Carbon emissions from energy consumption of Shandong province from 1995 to 2012 are calculated. Three zero-residual decomposition models (LMDI, MRCI and Shapley value models) are introduced for decomposing carbon emissions. Based on the results, Kendall coordination coefficient method is employed for testing their compatibility, and an optimal weighted combination decomposition model is constructed for improving the objectivity of decomposition. STIRPAT model is applied to evaluate the impact of each factor on carbon emissions. The results show that, using 1995 as the base year, the cumulative effects of population, per capita GDP, energy consumption intensity, and energy consumption structure of Shandong province in 2012 are positive, while the cumulative effect of industrial structure is negative. Per capita GDP is the largest driver of the increasing carbon emissions and has a great impact on carbon emissions; energy consumption intensity is a weak driver and has certain impact on carbon emissions; population plays a weak driving role, but it has the most significant impact on carbon emissions; energy consumption structure is a weak driver of the increasing carbon emissions and has a weak impact on carbon emissions; industrial structure has played a weak inhibitory role, and its impact on carbon emissions is great. PMID:24977216

  7. Methods for quantifying variability and uncertainty in AP-42 emission factors: case studies for natural gas-fueled engines.

    PubMed

    Frey, H Christopher; Li, Song

    2003-12-01

    Quantitative methods for characterizing variability and uncertainty were applied to case studies of oxides of nitrogen and total organic carbon emission factors for lean-burn natural gas-fueled internal combustion engines. Parametric probability distributions were fit to represent inter-engine variability in specific emission factors. Bootstrap simulation was used to quantify uncertainty in the fitted cumulative distribution function and in the mean emission factor. Some methodological challenges were encountered in analyzing the data. For example, in one instance, five data points were available, with each data point representing a different market share. Therefore, an approach was developed in which parametric distributions were fitted to population-weighted data. The uncertainty in mean emission factors ranges from as little as approximately +/-10% to as much as -90 to +180%. The wide range of uncertainty in some emission factors emphasizes the importance of recognizing and accounting for uncertainty in emissions estimates. The skewness in some uncertainty estimates illustrates the importance of using numerical simulation approaches that do not impose restrictive symmetry assumptions on the confidence interval for the mean. In this paper, the quantitative method, the analysis results, and key findings are presented.

  8. Methods for quantifying variability and uncertainty in AP-42 emission factors: case studies for natural gas-fueled engines.

    PubMed

    Frey, H Christopher; Li, Song

    2003-12-01

    Quantitative methods for characterizing variability and uncertainty were applied to case studies of oxides of nitrogen and total organic carbon emission factors for lean-burn natural gas-fueled internal combustion engines. Parametric probability distributions were fit to represent inter-engine variability in specific emission factors. Bootstrap simulation was used to quantify uncertainty in the fitted cumulative distribution function and in the mean emission factor. Some methodological challenges were encountered in analyzing the data. For example, in one instance, five data points were available, with each data point representing a different market share. Therefore, an approach was developed in which parametric distributions were fitted to population-weighted data. The uncertainty in mean emission factors ranges from as little as approximately +/-10% to as much as -90 to +180%. The wide range of uncertainty in some emission factors emphasizes the importance of recognizing and accounting for uncertainty in emissions estimates. The skewness in some uncertainty estimates illustrates the importance of using numerical simulation approaches that do not impose restrictive symmetry assumptions on the confidence interval for the mean. In this paper, the quantitative method, the analysis results, and key findings are presented. PMID:14700131

  9. Diagrams and parastatistical factors for cascade emission of a pair of paraparticles

    NASA Astrophysics Data System (ADS)

    Nelson, Charles A.; Kraynova, Margarita; Mera, Calvin S.; Shapiro, Alanna M.

    2016-02-01

    The empirical absence to date of particles obeying parastatistics in high-energy collider experiments might be due to their large masses, weak scale couplings, and lack of gauge couplings. Paraparticles of order p =2 must be pair produced, so the lightest such particles are absolutely stable and so are excellent candidates to be associated with dark matter and/or dark energy. If there is a portal to such particles, from a new scalar A1 boson they might be cascade emitted as a pair of para-Majorana neutrinos as in A1→A2ν˘αν˘β or as a pair of neutral spin-zero paraparticles such as in A1→A2A ˘B ˘, where B ˘ is the anti-paraparticle to A ˘. In this paper, for an assumed supersymmetric-like "statistics portal" Lagrangian, the associated connected tree diagrams and their parastatistical factors are obtained for the case of order p =2 parastatistics. These factors are compared with the corresponding statistical factors for the analogous emission of a nondegenerate or a twofold degenerate pair which obey normal statistics. This shows that diagrams, and diagrammatic thinking, can be useful in perturbatively analyzing paraparticle processes. The parastatistical factor associated with each diagram does require explicit calculation.

  10. Modelling site-specific N2O emission factors from Austrian agricultural soils for targeted mitigation measures (NitroAustria)

    NASA Astrophysics Data System (ADS)

    Amon, Barbara; Zechmeister-Boltenstern, Sophie; Kasper, Martina; Foldal, Cecilie; Schiefer, Jasmin; Kitzler, Barbara; Schwarzl, Bettina; Zethner, Gerhard; Anderl, Michael; Sedy, Katrin; Gaugitsch, Helmut; Dersch, Georg; Baumgarten, Andreas; Haas, Edwin; Kiese, Ralf

    2016-04-01

    Results from a previous project "FarmClim" highlight that the IPCC default emission factor is not able to reflect region specific N2O emissions from Austrian arable soils. The methodology is limited in identifying hot spots and hot moments of N2O emissions. When estimations are based on default emission factors no recommendations can be given on optimisation measures that would lead to a reduction of soil N2O emissions. The better the knowledge is about Nitrogen and Carbon budgets in Austrian agricultural managed soils the better the situation can be reflected in the Austrian GHG emission inventory calculations. Therefore national and regionally modelled emission factors should improve the evidence for national deviation from the IPCC default emission factors and reduce the uncertainties. The overall aim of NitroAustria is to identify the drivers for N2O emissions on a regional basis taking different soil types, climate, and agricultural management into account. We use the LandscapeDNDC model to update the N2O emission factors for N fertilizer and animal manure applied to soils. Key regions in Austria were selected and region specific N2O emissions calculated. The model runs at sub-daily time steps and uses data such as maximum and minimum air temperature, precipitation, radiation, and wind speed as meteorological drivers. Further input data are used to reflect agricultural management practices, e.g., planting/harvesting, tillage, fertilizer application, irrigation and information on soil and vegetation properties for site characterization and model initialization. While at site scale, arable management data (crop cultivation, rotations, timings etc.) is obtained by experimental data from field trials or observations, at regional scale such data need to be generated using region specific proxy data such as land use and management statistics, crop cultivations and yields, crop rotations, fertilizer sales, manure resulting from livestock units etc. The farming

  11. Emissions of PAHs from indoor crop residue burning in a typical rural stove: emission factors, size distributions, and gas-particle partitioning.

    PubMed

    Shen, Guofeng; Wang, Wei; Yang, Yifeng; Ding, Junnan; Xue, Miao; Min, Yujia; Zhu, Chen; Shen, Huizhong; Li, Wei; Wang, Bin; Wang, Rong; Wang, Xilong; Tao, Shu; Russell, Armistead G

    2011-02-15

    Indoor combustion of crop residues for cooking or heating is one of the most important emission sources of polycyclic aromatic hydrocarbons (PAHs) in developing countries. However, data on PAH emission factors (EFs) for burning crop residues indoor, particularly those measured in the field, were scarce, leading to large uncertainties in the emission inventories. In this study, EFs of PAHs for nine commonly used crop residues burned in a typical Chinese rural cooking stove were measured in a simulated kitchen. The measured EFs of total PAHs averaged at 63 ± 37 mg/kg, ranging from 27 to 142 mg/kg, which were higher than those measured in chamber experiments, implying that the laboratory experiment-based emission and risk assessment should be carefully reviewed. EFs of gaseous and particulate phase PAHs were 27 ± 13 and 35 ± 23 mg/kg, respectively. Composition profiles and isomer ratios of emitted PAHs were characterized. Stepwise regressions found that modified combustion efficiency and fuel moisture were the most important factors affecting the emissions. There was 80 ± 6% of PAHs associated with PM2.5, and the mass percentage of PAHs in fine particles increased as the molecular weight increased. For freshly emitted PAHs, absorption into organic carbon, rather than adsorption, dominated the gas-particle partitioning.

  12. Aerosol particle and trace gas emissions from earthworks, road construction, and asphalt paving in Germany: Emission factors and influence on local air quality

    NASA Astrophysics Data System (ADS)

    Faber, Peter; Drewnick, Frank; Borrmann, Stephan

    2015-12-01

    Aerosol emissions from construction sites have a strong impact on local air quality. The chemical and physical characteristics of particles and trace gases emitted by earthworks (excavation and loading of soil as well as traffic on unpaved roads) and road works (asphalt sawing, smashing, soil compacting, asphalt paving) have therefore been addressed in this study by using a mobile set-up of numerous modern online aerosol and trace gas instruments including a high-resolution aerosol mass spectrometer. Fuel-based emission factors for several variables have been determined, showing that earthwork activities and compacting by use of a plate compactor revealed the highest median emission factors for PM10 (up to 54 g l-1). Construction activities were assigned to contribute about 17% (36 000 t a-1) to total PM10 emissions and 3% (13 500 t a-1) to total traffic-related NOx emissions in Germany. In particular, calculated PM10 emissions by earthworks are about 15 800 t a-1 corresponding to 44% of total PM10 emissions by construction activities in Germany. Mechanical processes such as asphalt sawing (PM1/PM10 = 18 ± 31%), soil compacting by a plate compactor (PM1/PM10 = 5 ± 6%) and earthworks (PM1/PM10 = 2 ± 5%) emit predominantly coarse mineral dust particles. Contrary to that, particle emissions by thermal construction processes (asphalt paving: PM1/PM10 = 62 ± 14%) and by the internal combustion engines of heavy machinery (e.g. road roller PM1/PM10 = 94 ± 9%) are mostly in the submicron range. These particles were mainly composed of organics containing non-polar saturated and unsaturated hydrocarbons (e.g. asphalting: O:C < 0.01, H:C = 2.01). Besides construction activities, mineral dust is also emitted over cleared land by wind-driven resuspension depending on wind speed. PM10 emissions by construction activities often result in local concentrations > 100 μg m-3 and can easily breach the European limit level of PM10. This study also shows that particulate mineral

  13. Field Studies Show That In Situ Greenhouse Gas Emission Factors for East African Agriculture Are Less Than IPCC Values

    NASA Astrophysics Data System (ADS)

    Pelster, D.; Butterbach-Bahl, K.; Rufino, M.; Rosenstock, T. S.; Wanyama, G.

    2015-12-01

    Greenhouse gas (GHG) emissions from African agricultural systems are thought to comprise a large portion of total emissions from the continent, however these estimates have been calculated using emission factors (EF) from other regions due to the lack of field studies in Africa, which results in large uncertainties for these estimates. Field measurements from western Kenya calculating emissions over a year in 59 different sites found that GHG emissions from typical smallholder farms ranged from 2.8 to 15.0 Mg CO2-C ha-1, -6.0 to 2.4 kg CH4-C ha-1 and -0.1 to 1.8 kg N2O-N ha-1, and were not affected by management intensity. The lack of a response in N2O emissions to N fertilization suggests that the EF currently used in national inventories overestimates N2O emissions from typical smallholder agriculture. Another study measuring N2O and CH4 emissions from manure deposited by grazing cattle found that the N2O EF ranged from 0.1 to 0.2%, while the CH4 EF ranged from 0.04 to 0.14 Kg CH4-C per 173 kg animal. These suggest that the current IPCC EF overestimate agricultural soil and manure GHG emissions for Kenya, and likely for much of East Africa.

  14. Fertiliser-induced nitrous oxide emissions from vegetable production in the world and the regulating factors: A review

    NASA Astrophysics Data System (ADS)

    Rezaei Rashti, Mehran; Wang, Weijin; Moody, Phil; Chen, Chengrong; Ghadiri, Hossein

    2015-07-01

    The emission of nitrous oxide (N2O) from vegetable fields contributes to the global greenhouse gases budget. However, reliable estimation of N2O emissions from vegetable production in the word has been lack. Vegetable cropping systems are characterised with high N application rates, irrigation, intensive production and multiple planting-harvest cycles during the year. Improved understanding of the key factors controlling N2O production is critical for developing effective mitigation strategies for vegetable cropping systems under different climate, soil type and management practices. Based on a comprehensive literature review and data analysis, we estimated the global N2O emission from vegetable production using seasonal fertiliser-induced emission factors (EFs) and examined the relationship of the seasonal emissions and EFs to possible controlling factors. The global average seasonal EF for vegetable fields is around 0.94% of applied N fertiliser, which is very similar to the Intergovernmental Panel on Climate Change (IPCC) annual emission factor of 1.0% for all cropping systems. The total N2O emission from global vegetable production is estimated to be 9.5 × 107 kg N2O-N yr-1, accounting for 9.0% of the total N2O emissions from synthetic fertilisers. Stepwise multiple regression analysis on the relationships of soil properties, climatic factors and N application rates to seasonal N2O emissions and N2O EFs showed that N fertiliser application rate is the main regulator of seasonal N2O emission from vegetable fields but the seasonal EFs are negatively related to soil organic carbon (SOC) content. In fields receiving ≥250 kg ha-1 N fertiliser, 67% (n = 23, P ≤ 0.01) of the variation in seasonal emissions can be explained by the combined effects of N application rate, mean water-filled pore space (WFPS) and air temperature, while 59% (n = 23, P ≤ 0.01) of the variation in seasonal EFs relates to temperature, mean WFPS and soil pH. The result also shows that in

  15. Emission Factors of Greenhouse Gases and Particulates from Australian Savanna Fires

    NASA Astrophysics Data System (ADS)

    Desservettaz, M.; Paton-Walsh, C.; Griffith, D. W. T.; Kettlewell, G.; Wilson, S. R.; Keywood, M. D.; van der Schoot, M. V.; Selleck, P. W.; Ward, J.; Harnwell, J.; Reisen, F.; Lawson, S. J.; Ristovski, Z.; Mallet, M.; Miljevic, B.; Atkinson, B.; Milic, A.

    2015-12-01

    In June 2014 a measurement campaign took place at Gunn Point in the Northern Territory, Australia, aimed at characterising the emissions from early dry season savanna fires. The campaign was especially focused on understanding aerosol composition and size distribution. Equipment deployed to measure aerosol properties included a multi-angle absorption photometer, a nephelometer, a cloud condensation nuclei counter, a condensation particle counter, two scanning mobility particle sizer, two aerosol mass spectrometers (one a time of flight instrument) , a multi-axis differential optical absorption spectrometer, a volatility-humidity tandem differential mobility analyser and two high volume aerosol samplers (one PM10 and one MOUDI). In addition there were measurements of mercury in both gas and aerosol phase. Complementary measurements of trace gases were provided by a proton transfer reaction mass spectrometer, a volatile organic compounds sequencer, a Fourier transform spectrometer, an ozone analyser and a nitrogen oxides monitor. This presentation will present results from the Fourier transform spectrometer, the scanning mobility particulate sizer, the beta attenuation monitor and the aerosol mass spectrometer. In particular individual fire events have been identified and emission factors calculated for CO2, CO, CH4 N2O and aerosols (PM1, PM10, Aitken and Accumulation mode).

  16. Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate which Fires Produce Ozone

    NASA Technical Reports Server (NTRS)

    Chatfield, Robert B.; Andreae, Meinrat O.

    2016-01-01

    Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(burn) = delta C(tot) added to the fire plume, where C(tot) approximately equals (CO2 = CO). Mixed-effects regression can estimate pre-fire background values of C(tot) (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta, epsilon lambda tau alpha-x(sub I)/C(sub burn))I,j. MERET and "consensus" require more than emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (b scant, b abs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx binding to

  17. Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate Which Fires Produce Ozone

    NASA Technical Reports Server (NTRS)

    Chatfield, Robert B.; Andreae, Meinrat O.

    2015-01-01

    Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(sub burn) = delta C(sub tot) added to the fire plume, where C(sub tot) approximately equals (CO2 + CO). Mixed-effects regression can estimate pre-fire background values of Ctot (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta epsilon lambda tau alpha-x(sub i)/(C(sub burn))i,j., MERET and "consensus" require more than two emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (bscat, babs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx

  18. Emission factor and balance of mercury in fish farms in an artificial reservoir in NE Brazil.

    PubMed

    Oliveira, Karen Figueiredo; Lacerda, Luiz Drude; Peres, Tiago Farias; Bezerra, Moises Fernandes; Dias, Francisco José da Silva

    2015-11-01

    This paper estimated the mercury (Hg), emission factor, and mass balance from caged fish farming in the Castanhão Reservoir, NE Brazil, based on monitoring of a typical farm of Nile tilapia (Oreochromis niloticus). The total Hg input to the farm reached 1.45 gHg ha(-1) year(-1), from which 0.21 gHg ha(-1) year(-1) was exported out as fish biomass, ultimately resulting in an emission factor of 1.24 gHg ha(-1) year(-1) for the reservoir or approximately 8.27 mgHg ton fish(-1) year(-1) produced. Most of the input came from aquafeeds with concentrations varying from 1.4 to 31.1 ng g(-1), depending on the type of aquafeed. The Hg concentrations in fish were very low and varied from 1.0 to 2.9 ng g(-1). These values are two orders of magnitude lower than the legal limit for human consumption. The estimated total annual discharge of Hg from farming into the reservoir is 174 g for 18,000 tons of fish produced and may reach 387 g when the reservoir reaches its total capacity (40,000 tons), which is expected to occur in 2020. The mass balance, considering the deposition and accumulation rates, showed that approximately 40% of the total Hg input accumulate in farm sediments (0.72 g ha(-1) year(-1)), which is approximately 60% of the deposition rate estimated through the sediment traps and suggests that 0.54 gHg ha(-1) year(-1) could eventually be transported out of the farm to the reservoir. Notwithstanding these facts, the total annual input of Hg from fish farming to the Castanhão Reservoir is less than 1.0% of the total input from anthropogenic sources. PMID:26233746

  19. Emission factor and balance of mercury in fish farms in an artificial reservoir in NE Brazil.

    PubMed

    Oliveira, Karen Figueiredo; Lacerda, Luiz Drude; Peres, Tiago Farias; Bezerra, Moises Fernandes; Dias, Francisco José da Silva

    2015-11-01

    This paper estimated the mercury (Hg), emission factor, and mass balance from caged fish farming in the Castanhão Reservoir, NE Brazil, based on monitoring of a typical farm of Nile tilapia (Oreochromis niloticus). The total Hg input to the farm reached 1.45 gHg ha(-1) year(-1), from which 0.21 gHg ha(-1) year(-1) was exported out as fish biomass, ultimately resulting in an emission factor of 1.24 gHg ha(-1) year(-1) for the reservoir or approximately 8.27 mgHg ton fish(-1) year(-1) produced. Most of the input came from aquafeeds with concentrations varying from 1.4 to 31.1 ng g(-1), depending on the type of aquafeed. The Hg concentrations in fish were very low and varied from 1.0 to 2.9 ng g(-1). These values are two orders of magnitude lower than the legal limit for human consumption. The estimated total annual discharge of Hg from farming into the reservoir is 174 g for 18,000 tons of fish produced and may reach 387 g when the reservoir reaches its total capacity (40,000 tons), which is expected to occur in 2020. The mass balance, considering the deposition and accumulation rates, showed that approximately 40% of the total Hg input accumulate in farm sediments (0.72 g ha(-1) year(-1)), which is approximately 60% of the deposition rate estimated through the sediment traps and suggests that 0.54 gHg ha(-1) year(-1) could eventually be transported out of the farm to the reservoir. Notwithstanding these facts, the total annual input of Hg from fish farming to the Castanhão Reservoir is less than 1.0% of the total input from anthropogenic sources.

  20. Emission factors and detailed chemical composition of smoke particles from the 2010 wildfire season

    NASA Astrophysics Data System (ADS)

    Vicente, Ana; Alves, Célia; Calvo, Ana I.; Fernandes, Ana P.; Nunes, Teresa; Monteiro, Cristina; Almeida, Susana Marta; Pio, Casimiro

    2013-06-01

    This paper complements the information previously published (Atmospheric Environment 45, 641-649) on gaseous and particulate emissions from wildfires in Portugal for summer 2009, in an attempt at obtaining more extensive, complete and representative databases on emission factors and detailed chemical characterisation of smoke particles. Here, emission factors for carbon oxides (CO2 and CO), total hydrocarbons (THC), fine (PM2.5) and coarse (PM2.5-10) particles obtained for fires occurring in Portugal in summer 2010 are presented. The carbonaceous content (OC and EC), water-soluble ions, elements and organic composition of smoke particles were, respectively, analysed by a thermal-optical transmission technique, ion chromatography, instrumental neutron activation analysis (INAA) and gas chromatography-mass spectrometry (GC-MS). The particle mass concentrations were in the ranges 0.69-25 mg m-3 for PM2.5 and 0.048-3.1 mg m-3 for PM2.5-10. PM2.5 particles represented 91 ± 5.7% of the PM10 mass. The OC/EC ratios in fine and coarse particles ranged from 2.5 to 205 and from 1.7 to 328, respectively. The water-soluble ions represented, on average, 3.9% and 2.8% of PM2.5 and PM2.5-10 mass, respectively. In general, the dominant ions in the water extracts were Na+, NH4+, Cl- and NO3- for the PM2.5 fraction, and K+, Mg2+, Ca2+ and SO42- for the PM2.5-10 fraction. The K+/EC and K+/OC ratios obtained in this study were, on average, 0.22 ± 0.23 and 0.011 ± 0.014 for PM2.5 and 0.83 ± 1.0 and 0.024 ± 0.023 for PM2.5-10 particles, respectively. The K+/levoglucosan ratio was, on average, 2.0 for PM2.5 and 3.1 for PM2.5-10 particles. Levoglucosan was detected at mass fractions of 1.6-8.7 mg g-1 OC in PM2.5 and 2.7-56 mg g-1 OC in PM2.5-10. The dominant elements detected in the smoke samples were Na, Br, Cr, Fe, K, Rb and Zn. The most representative organic constituents in the smoke samples were acids, alcohols, terpenoid-type compounds, sugars and phenols, in both size fractions.

  1. Emission factors for hydraulically fractured gas wells derived using well- and battery-level reported data for Alberta, Canada.

    PubMed

    Tyner, David R; Johnson, Matthew R

    2014-12-16

    A comprehensive technical analysis of available industry-reported well activity and production data for Alberta in 2011 has been used to derive flaring, venting, and diesel combustion greenhouse gas and criteria air contaminant emission factors specifically linked to drilling, completion, and operation of hydraulically fractured natural gas wells. Analysis revealed that in-line ("green") completions were used at approximately 53% of wells completed in 2011, and in other cases the majority (99.5%) of flowback gases were flared rather than vented. Comparisons with limited analogous data available in the literature revealed that reported total flared and vented natural gas volumes attributable to tight gas well-completions were ∼ 6 times larger than Canadian Association of Petroleum Producers (CAPP) estimates for natural gas well-completion based on wells ca. 2000, but 62% less than an equivalent emission factor that can be derived from U.S. EPA data. Newly derived emission factors for diesel combustion during well drilling and completion are thought to be among the first such data available in the open literature, where drilling-related emissions for tight gas wells drilled in Alberta in 2011 were found to have increased by a factor of 2.8 relative to a typical well drilled in Canada in 2000 due to increased drilling lengths. From well-by-well analysis of production phase flared, vented, and fuel usage natural gas volumes reported at 3846 operating tight gas wells in 2011, operational emission factors were developed. Overall results highlight the importance of operational phase GHG emissions at upstream well sites (including on-site natural gas fuel use), and the critical levels of uncertainty in current estimates of liquid unloading emissions. PMID:25402949

  2. Emission factors for hydraulically fractured gas wells derived using well- and battery-level reported data for Alberta, Canada.

    PubMed

    Tyner, David R; Johnson, Matthew R

    2014-12-16

    A comprehensive technical analysis of available industry-reported well activity and production data for Alberta in 2011 has been used to derive flaring, venting, and diesel combustion greenhouse gas and criteria air contaminant emission factors specifically linked to drilling, completion, and operation of hydraulically fractured natural gas wells. Analysis revealed that in-line ("green") completions were used at approximately 53% of wells completed in 2011, and in other cases the majority (99.5%) of flowback gases were flared rather than vented. Comparisons with limited analogous data available in the literature revealed that reported total flared and vented natural gas volumes attributable to tight gas well-completions were ∼ 6 times larger than Canadian Association of Petroleum Producers (CAPP) estimates for natural gas well-completion based on wells ca. 2000, but 62% less than an equivalent emission factor that can be derived from U.S. EPA data. Newly derived emission factors for diesel combustion during well drilling and completion are thought to be among the first such data available in the open literature, where drilling-related emissions for tight gas wells drilled in Alberta in 2011 were found to have increased by a factor of 2.8 relative to a typical well drilled in Canada in 2000 due to increased drilling lengths. From well-by-well analysis of production phase flared, vented, and fuel usage natural gas volumes reported at 3846 operating tight gas wells in 2011, operational emission factors were developed. Overall results highlight the importance of operational phase GHG emissions at upstream well sites (including on-site natural gas fuel use), and the critical levels of uncertainty in current estimates of liquid unloading emissions.

  3. Calculated hydroxyl A2 sigma --> X2 pi (0, 0) band emission rate factors applicable to atmospheric spectroscopy

    NASA Technical Reports Server (NTRS)

    Cageao, R. P.; Ha, Y. L.; Jiang, Y.; Morgan, M. F.; Yung, Y. L.; Sander, S. P.

    1997-01-01

    A calculation of the A2 sigma --> X2 pi (0, 0) band emission rate factors and line center absorption cross sections of OH applicable to its measurement using solar resonant fluorescence in the terrestrial atmosphere is presented in this paper. The most accurate available line parameters have been used. Special consideration has been given to the solar input flux because of its highly structured Fraunhofer spectrum. The calculation for the OH atmospheric emission rate factor in the solar resonant fluorescent case is described in detail with examples and intermediate results. Results of this calculation of OH emission rate factors for individual rotational lines are on average 30% lower than the values obtained in an earlier work.

  4. Development of Methane and Nitrous Oxide Emission Factors for the Biomass Fired Circulating Fluidized Bed Combustion Power Plant

    PubMed Central

    Cho, Chang-Sang; Sa, Jae-Hwan; Lim, Ki-Kyo; Youk, Tae-Mi; Kim, Seung-Jin; Lee, Seul-Ki; Jeon, Eui-Chan

    2012-01-01

    This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH4), Nitrous oxide (N2O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH4 and N2O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH4 and N2O exhausted from the CFB boiler. As a result, the emission factors of CH4 and N2O are 1.4 kg/TJ (0.9–1.9 kg/TJ) and 4.0 kg/TJ (2.9–5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N2O emission, compared to the emission factor of the CFB boiler using fossil fuel. PMID:23365540

  5. Development of methane and nitrous oxide emission factors for the biomass fired circulating fluidized bed combustion power plant.

    PubMed

    Cho, Chang-Sang; Sa, Jae-Hwan; Lim, Ki-Kyo; Youk, Tae-Mi; Kim, Seung-Jin; Lee, Seul-Ki; Jeon, Eui-Chan

    2012-01-01

    This study makes use of this distinction to analyze the exhaust gas concentration and fuel of the circulating fluidized bed (CFB) boiler that mainly uses wood biomass, and to develop the emission factors of Methane (CH(4)), Nitrous oxide (N(2)O). The fuels used as energy sources in the subject working sites are Wood Chip Fuel (WCF), RDF and Refused Plastic Fuel (RPF) of which heating values are 11.9 TJ/Gg, 17.1 TJ/Gg, and 31.2 TJ/Gg, respectively. The average concentrations of CH(4) and N(2)O were measured to be 2.78 ppm and 7.68 ppm, respectively. The analyzed values and data collected from the field survey were used to calculate the emission factor of CH(4) and N(2)O exhausted from the CFB boiler. As a result, the emission factors of CH(4) and N(2)O are 1.4 kg/TJ (0.9-1.9 kg/TJ) and 4.0 kg/TJ (2.9-5.3 kg/TJ) within a 95% confidence interval. Biomass combined with the combustion technology for the CFB boiler proved to be more effective in reducing the N(2)O emission, compared to the emission factor of the CFB boiler using fossil fuel. PMID:23365540

  6. Concentrations and emission factors for PM2.5 and PM10 from road traffic in Sweden

    NASA Astrophysics Data System (ADS)

    Ferm, Martin; Sjöberg, Karin

    2015-10-01

    PM10 concentrations exceed the guidelines in some Swedish cities and the limit values will likely be further reduced in the future. In order to gain more knowledge of emission factors for road traffic and concentrations of PM10 and PM2.5, existing monitoring stations in two cities, Gothenburg and Umeå, with international E-road thoroughfares, were complemented with some PM2.5 measurements. Emission factors for PM10 and PM2.5 were estimated using NOX as a tracer. Monitoring data from kerbside and urban background sites in Gothenburg during 2006-2010 and in Umeå during 2006-2012 were used. NOX emissions were estimated from the traffic flow and emission factors calculated from the HBEFA3.1 model. PM2.5 constitutes the finer part of PM10. Emissions of the coarser part of PM10 (PM10-PM2.5) are suppressed when roads are wet and show a maximum during spring when the roads dry up and studded tyres are still used. Less than 1% of the road wear caused by studded tyres give rise to airborne PM2.5-10 particles. The NOX emission factors decrease with time in the used model, due to the renewal of the vehicle fleet. However, the NOX concentrations resulting from the roads show no clear trend. The air dispersion is an important factor controlling the PM concentration near the road. The dispersion has a minimum in winter and during midnight. The average street level concentrations of PM10 and PM2.5 in Gothenburg were 21 ± 20 and 8 ± 6 μg m-3 respectively, which is 36% and 22% higher than the urban background concentrations. Despite the four times lower traffic flow in Umeå compared to Gothenburg, the average particle concentrations were very similar; 21 ± 31 and 7 ± 5 μg m-3 for PM10 and PM2.5 respectively. These concentrations were, however, 108% and 55% higher than the urban background concentrations in Umeå. The emission factors for PM10 decreased with time, and the average factor was 0.06 g km-1 vehichle-1. The emission factors for PM2.5 are very uncertain due to the

  7. A study on the evaluations of emission factors and uncertainty ranges for methane and nitrous oxide from combined-cycle power plant in Korea.

    PubMed

    Lee, Seehyung; Kim, Jinsu; Lee, Jeongwoo; Lee, Seongho; Jeon, Eui-Chan

    2013-01-01

    In this research, in order to develop technology/country-specific emission factors of methane (CH(4)) and nitrous oxide (N(2)O), a total of 585 samples from eight gas-fired turbine combined cycle (GTCC) power plants were measured and analyzed. The research found that the emission factor for CH(4) stood at "0.82 kg/TJ", which was an 18 % lower than the emission factor for liquefied natural gas (LNG) GTCC "1 kg/TJ" presented by Intergovernmental Panel on Climate Change (IPCC). The result was 8 % up when compared with the emission factor of Japan which stands at "0.75 kg/TJ". The emission factor for N(2)O was "0.65 kg/TJ", which is significantly lower than "3 kg/TJ" of the emission factor for LNG GTCC presented by IPCC, but over six times higher than the default N(2)O emission factor of LNG. The evaluation of uncertainty was conducted based on the estimated non-CO(2) emission factors, and the ranges of uncertainty for CH(4) and N(2)O were between -12.96 and +13.89 %, and -11.43 and +12.86 %, respectively, which is significantly lower than uncertainties presented by IPCC. These differences proved that non-CO(2) emissions can change depending on combustion technologies; therefore, it is vital to establish country/technology-specific emission factors.

  8. A study on the evaluations of emission factors and uncertainty ranges for methane and nitrous oxide from combined-cycle power plant in Korea.

    PubMed

    Lee, Seehyung; Kim, Jinsu; Lee, Jeongwoo; Lee, Seongho; Jeon, Eui-Chan

    2013-01-01

    In this research, in order to develop technology/country-specific emission factors of methane (CH(4)) and nitrous oxide (N(2)O), a total of 585 samples from eight gas-fired turbine combined cycle (GTCC) power plants were measured and analyzed. The research found that the emission factor for CH(4) stood at "0.82 kg/TJ", which was an 18 % lower than the emission factor for liquefied natural gas (LNG) GTCC "1 kg/TJ" presented by Intergovernmental Panel on Climate Change (IPCC). The result was 8 % up when compared with the emission factor of Japan which stands at "0.75 kg/TJ". The emission factor for N(2)O was "0.65 kg/TJ", which is significantly lower than "3 kg/TJ" of the emission factor for LNG GTCC presented by IPCC, but over six times higher than the default N(2)O emission factor of LNG. The evaluation of uncertainty was conducted based on the estimated non-CO(2) emission factors, and the ranges of uncertainty for CH(4) and N(2)O were between -12.96 and +13.89 %, and -11.43 and +12.86 %, respectively, which is significantly lower than uncertainties presented by IPCC. These differences proved that non-CO(2) emissions can change depending on combustion technologies; therefore, it is vital to establish country/technology-specific emission factors. PMID:23001757

  9. Evaluation of carbon dioxide emission factor from urea during rice cropping season: A case study in Korean paddy soil

    NASA Astrophysics Data System (ADS)

    Kim, Gil Won; Jeong, Seung Tak; Kim, Gun Yeob; Kim, Pil Joo; Kim, Sang Yoon

    2016-08-01

    Fertilization with urea can lead to a loss of carbon dioxide (CO2) that was fixed during the industrial production process. The extent of atmospheric CO2 removal from urea manufacturing was estimated by the Industrial Processes and Product Use sector (IPPU sector). On its basis, the Intergovernmental Panel on Climate Change (IPCC) has proposed a value of 0.2 Mg C per Mg urea (available in 2006 revised IPCC guidelines for greenhouse gas inventories), which is the mass fractions of C in urea, as the CO2 emission coefficient from urea for the agricultural sector. Notably, due to the possibility of bicarbonate leaching to waters, all C in urea might not get released as CO2 to the atmosphere. Hence, in order to provide an accurate value of the CO2 emission coefficient from applied urea in the rice ecosystem, the CO2 emission factors were characterized under different levels of 13C-urea applied paddy field in the current study. The total CO2 fluxes and rice grain yields increased significantly with increasing urea application (110-130 kg N ha-1) and thereafter, decreased. However, with increasing 13C-urea application, a significant and proportional increase of the 13CO2sbnd C emissions from 13C-urea was also observed. From the relationships between urea application levels and 13CO2sbnd C fluxes from 13C-urea, the CO2sbnd C emission factor from urea was estimated to range between 0.0143 and 0.0156 Mg C per Mg urea. Thus, the CO2sbnd C emission factor of this study is less than that of the value proposed by IPCC. Therefore, for the first time, we propose to revise the current IPCC guideline value of CO2sbnd C emission factor from urea as 0.0143-0.0156 Mg C per Mg urea for Korean paddy soils.

  10. Phthalates and nonylphenols in urban runoff: Occurrence, distribution and area emission factors.

    PubMed

    Björklund, Karin; Cousins, Anna Palm; Strömvall, Ann-Margret; Malmqvist, Per-Arne

    2009-08-01

    The urban water system is believed to be an important sink for the nonpoint-source pollutants nonylphenols and phthalates. The presence of nonylphenols (NPs), nonylphenol ethoxylates (NPEOs), and eight phthalates was analyzed in urban stormwater and sediment from three catchment areas in Sweden. Emission loads for these substances were then calculated for a specific urban catchment area. In addition, substance distribution in road runoff passing through a sedimentation facility was modeled using a modified QWASI-model for chemical fate. High concentrations of DEHP, DIDP and DINP (emission factors from an urban highway environment revealed that as much as 2.1 kg of total phthalates and 200 g of NP and NPEOs may be emitted per hectare and year. The results indicate that all monitored phthalates, branched NPs and lower NPEOs are present in Swedish urban water systems. The long-chain phthalates DIDP and DINP are believed to occur at higher concentrations than other phthalates because of their higher environmental persistence and their increasing use in Sweden.

  11. VOC and hazardous air pollutant emission factors for military aircraft fuel cell inspection, maintenance, and repair operations

    SciTech Connect

    Nand, K.; Sahu, R.

    1997-12-31

    Accurate emission estimation is one of the key aspects of implementation of any air quality program. The Federal Title 5 program, specially requires an accurate and updated inventory of criteria as well hazardous air pollutants (HAPs) from all facilities. An overestimation of these two categories of pollutants, may cause the facility to be classified as a major source, when in fact it may actually be a minor source, and may also trigger unnecessary compliance requirements. A good example of where overestimation of volatile organic compounds (VOCs) and HAPs is easily possible are military aircraft fuel cells inspection, maintenance, and repair operations. The military aircraft fuel tanks, which are commonly identified as fuel cells, are routinely inspected for maintenance and repairs at military aircraft handling facilities. Prior to entry into the fuel cell by an inspector, fuel cells are first drained into bowsers and then purged with fresh air; the purged air is generally released without any controls to the atmosphere through a stack. The VOC and HAPs emission factors from these operations are not available in the literature for JP-8 fuel, which is being used increasingly by military aircraft. This paper presents two methods for estimating emissions for this source type, which are based on engineering calculations and professional judgment. This paper presents several methods for estimating emissions for this source type, which are based on engineering calculations and professional judgment. There are three emission producing phases during the draining and purging operations: (1) emissions during splash loading of bowsers (unloading of fuel cells), (2) emissions from spillage of fuel during loading of bowsers, and (3) emissions from fuel cell purging operations. Results of the emission estimation, including a comparison of the two emission estimation methods are presented in this paper.

  12. Determination of car on-road black carbon and particle number emission factors and comparison between mobile and stationary measurements

    NASA Astrophysics Data System (ADS)

    Ježek, I.; Drinovec, L.; Ferrero, L.; Carriero, M.; Močnik, G.

    2015-01-01

    We have used two methods for measuring emission factors (EFs) in real driving conditions on five cars in a controlled environment: the stationary method, where the investigated vehicle drives by the stationary measurement platform and the composition of the plume is measured, and the chasing method, where a mobile measurement platform drives behind the investigated vehicle. We measured EFs of black carbon and particle number concentration. The stationary method was tested for repeatability at different speeds and on a slope. The chasing method was tested on a test track and compared to the portable emission measurement system. We further developed the data processing algorithm for both methods, trying to improve consistency, determine the plume duration, limit the background influence and facilitate automatic processing of measurements. The comparison of emission factors determined by the two methods showed good agreement. EFs of a single car measured with either method have a specific distribution with a characteristic value and a long tail of super emissions. Measuring EFs at different speeds or slopes did not significantly influence the EFs of different cars; hence, we propose a new description of vehicle emissions that is not related to kinematic or engine parameters, and we rather describe the vehicle EF with a characteristic value and a super emission tail.

  13. Determination of car on-road black carbon and particle number emission factors and comparison between mobile and stationary measurements

    NASA Astrophysics Data System (ADS)

    Ježek, I.; Drinovec, L.; Ferrero, L.; Carriero, M.; Močnik, G.

    2014-06-01

    We have used two methods for measuring emission factors (EF) in real driving conditions on five cars in a controlled environment: the stationary method, where the investigated vehicle drives by the stationary measurement platform and the composition of the plume is measured; and the chasing method, where a mobile measurement platform drives behind the investigated vehicle. We measured EF of black carbon and particle number concentration. The stationary method was tested for repeatability at different speeds and on a slope. The chasing method was tested on a test track and compared to the portable emission measurement system. We further developed the data processing algorithm for both methods, trying to improve consistency, determine the plume duration, limit the background influence and facilitate automatic processing of measurements. The comparison of emission factors determined by the two methods showed good agreement. EFs of a single car measured with either method have a specific distribution with a characteristic value and a long tail of super emissions. Measuring EFs at different speeds or slopes did not significantly influence the EFs of different cars, hence we propose a new description of vehicle emissions that is not related to kinematic or engine parameters, rather we describe the vehicle EF with a characteristic value and a "super emission" tail.

  14. Measurements with UV-DOAS in a street tunnel for validation of emission factors for road vehicles

    NASA Astrophysics Data System (ADS)

    Rodler, Johannes; Sturm, Peter J.; Lechner, Bernhard

    2001-02-01

    12 The emission behavior of road vehicles is usually estimated by application of emission factors and models. The validity of such factors or models in real world situations can be investigated by tunnel measurements, because road tunnels can be considered as big laboratories with well known boundary conditions. Tunnel experiments were carried out in the 10 km long Plabutschtunnel near Graz, Austria for a period of six weeks in November 1998 and another four weeks in May 1999. A UV- DOAS-system was operated in open-path mode located some 4 km inside the tunnel with pathlengths of 220 m to 430 m. To have an idea about the uniformity of the pollutant air mixture within the path, a comparison of NO2 measurements performed with a standard chemiluminescent analyser (point measurement) and the DOAS system (open-path measurement) was done. Therefore a standard air quality monitoring-system (AQM) in a container was installed in a niche inside the tunnel on one end of the DOAS path. The analysis of data showed good agreement of emissions derived from the measurements with the existing PC and HDV emission factors for CO. This was not the case for benzene and NOx emissions obtained from heavy duty vehicles.

  15. Are climate and land cover changes in East Asia important factors for dust emission variability in the past 30 years?

    NASA Astrophysics Data System (ADS)

    Chow, R. M. K.; Tai, A. P. K.; Ridley, D. A.; Kok, J. F.

    2015-12-01

    Mineral dust is important for climate because it alters the radiation budget, both directly by scattering sunlight and indirectly by influencing cloud processes. Studies have shown that the variability of dust emission is greatly affected by local wind speeds and land surface characteristics. Globally, land cover change is mainly driven by vegetation changes that modify the dust sources, which can be represented by changes in leaf area index (LAI), and its effect on East Asian dust emission under the backdrop of changing wind patterns has yet to be quantified. Here we present a study to investigate how climate and land cover changes might have modified dust emission in East Asia during 1982-2010 using the GEOS-Chem chemical transport model. New developments include a dynamic geomorphology-dependent dust emission scheme and better representation of vegetation effect on surface roughness and threshold wind speed. We also implement subgrid wind variability to reduce the resolution dependence of the model. The bias of modeled total aerosol optical depth (AOD) relative to observations is reduced from about -86% to -14%, mostly due to the inclusion of subgrid wind variability, but up to 10% of the emission improvements stem from the revised vegetation dependence. Simulations suggest that about 45 Tg, ~9% of the global dust emission, is from East Asia in spring. Sensitivity studies with changing historical LAI vs. surface wind show that climate variability might be a more important factor than land cover change contributing to dust emission variability and trends over the past 30 years.

  16. GHG emission factors developed for the collection, transport and landfilling of municipal waste in South African municipalities

    SciTech Connect

    Friedrich, Elena; Trois, Cristina

    2013-04-15

    Highlights: ► An average GHG emission factor for the collection and transport of municipal solid waste in South Africa is calculated. ► A range of GHG emission factors for different types of landfills (including dumps) in South Africa are calculated. ► These factors are compared internationally and their implications for South Africa and developing countries are discussed . ► Areas for new research are highlighted. - Abstract: Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5 dm{sup 3} (litres) per tonne of wet waste and the associated GHG emissions are about 15 kg CO{sub 2} equivalents (CO{sub 2} e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from −145 to 1016 kg CO{sub 2} e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532 kg CO{sub 2} e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement

  17. Driving factors of carbon dioxide emissions in China: an empirical study using 2006-2010 provincial data

    NASA Astrophysics Data System (ADS)

    Liu, Yu; Chen, Zhan-Ming; Xiao, Hongwei; Yang, Wei; Liu, Danhe; Chen, Bin

    2016-04-01

    The rapid urbanization of China has increased pressure on its environmental and ecological well being. In this study, the temporal and spatial profiles of China's carbon dioxide emissions are analyzed by taking heterogeneities into account based on an integration of the extended stochastic impacts using a geographically and temporally weighted regression model on population, affluence, and technology. Population size, urbanization rate, GDP per capita, energy intensity, industrial structure, energy consumption pattern, energy prices, and economy openness are identified as the key driving factors of regional carbon dioxide emissions and examined through the empirical data for 30 provinces during 2006-2010. The results show the driving factors and their spillover effects have distinct spatial and temporal heterogeneities. Most of the estimated time and space coefficients are consistent with expectation. According to the results of this study, the heterogeneous spatial and temporal effects should be taken into account when designing policies to achieve the goals of carbon dioxide emissions reduction in different regions.

  18. Black Carbon Concentrations and Diesel Vehicle Emission FactorsDerived from Coefficient of Haze Measurements in California:1967-2003

    SciTech Connect

    Kirchstetter, Thomas W.; Aguiar, Jeffery; Tonse, Shaheen; Novakov, T.

    2007-10-01

    We have derived ambient black carbon (BC) concentrations and estimated emission factors for on-road diesel vehicles from archived Coefficient of Haze (COH) data that was routinely collected beginning in 1967 at 11 locations in the San Francisco Bay Area. COH values are a measure of the attenuation of light by particles collected on a white filter, and available data indicate they are proportional to BC concentrations measured using the conventional aethalometer. Monthly averaged BC concentrations are up to five times greater in winter than summer, and, consequently, so is the population's exposure to BC. The seasonal cycle in BC concentrations is similar for all Bay Area sites, most likely due to area-wide decreased pollutant dispersion during wintertime. A strong weekly cycle is also evident, with weekend concentrations significantly lower than weekday concentrations, consistent with decreased diesel traffic volume on weekends. The weekly cycle suggests that, in the Bay Area, diesel vehicle emissions are the dominant source of BC aerosol. Despite the continuous increase in diesel fuel consumption in California, annual Bay Area average BC concentrations decreased by a factor of {approx}3 from the late 1960s to the early 2000s. Based on estimated annual BC concentrations, on-road diesel fuel consumption, and recent measurements of on-road diesel vehicle BC emissions, diesel BC emission factors decreased by an order of magnitude over the study period. Reductions in the BC emission factor reflect improved engine technology, emission controls and changes in diesel fuel composition. A new BC monitoring network is needed to continue tracking ambient BC trends because the network of COH monitors has recently been retired.

  19. Black Carbon Concentrations and Diesel Vehicle Emission Factors Derived from Coefficient of Haze Measurements in California: 1967-2003

    SciTech Connect

    Tast, CynthiaL; Kirchstetter, Thomas W.; Aguiar, Jeffery; Tonse, Shaheen; Novakov, T.; Fairley, David

    2007-11-09

    We have derived ambient black carbon (BC) concentrations and estimated emission factors for on-road diesel vehicles from archived Coefficient of Haze (COH) data that was routinely collected beginning in 1967 at 11 locations in the San Francisco Bay Area. COH values are a measure of the attenuation of light by particles collected on a white filter, and available data indicate they are proportional to BC concentrations measured using the conventional aethalometer. Monthly averaged BC concentrations are up to five times greater in winter than summer, and, consequently, so is the population?s exposure to BC. The seasonal cycle in BC concentrations is similar for all Bay Area sites, most likely due to area-wide decreased pollutant dispersion during wintertime. A strong weekly cycle is also evident, with weekend concentrations significantly lower than weekday concentrations, consistent with decreased diesel traffic volume on weekends. The weekly cycle suggests that, in the Bay Area, diesel vehicle emissions are the dominant source of BC aerosol. Despite the continuous increase in diesel fuel consumption in California, annual Bay Area average BC concentrations decreased by a factor of ~;;3 from the late 1960s to the early 2000s. Based on estimated annual BC concentrations, on-road diesel fuel consumption, and recent measurements of on-road diesel vehicle BC emissions, diesel BC emission factors decreased by an order of magnitude over the study period. Reductions in the BC emission factor reflect improved engine technology, emission controls and changes in diesel fuel composition. A new BC monitoring network is needed to continue tracking ambient BC trends because the network of COH monitors has recently been retired.

  20. Emission factors for high-emitting vehicles based on on-road measurements of individual vehicle exhaust with a mobile measurement platform.

    PubMed

    Park, Seong Suk; Kozawa, Kathleen; Fruin, Scott; Mara, Steve; Hsu, Ying-Kuang; Jakober, Chris; Winer, Arthur; Herner, Jorn

    2011-10-01

    Fuel-based emission factors for 143 light-duty gasoline vehicles (LDGVs) and 93 heavy-duty diesel trucks (HDDTs) were measured in Wilmington, CA using a zero-emission mobile measurement platform (MMP). The frequency distributions of emission factors of carbon monoxide (CO), nitrogen oxides (NO(x)), and particle mass with aerodynamic diameter below 2.5 microm (PM2.5) varied widely, whereas the average of the individual vehicle emission factors were comparable to those reported in previous tunnel and remote sensing studies as well as the predictions by Emission Factors (EMFAC) 2007 mobile source emission model for Los Angeles County. Variation in emissions due to different driving modes (idle, low- and high-speed acceleration, low- and high-speed cruise) was found to be relatively small in comparison to intervehicle variability and did not appear to interfere with the identification of high emitters, defined as the vehicles whose emissions were more than 5 times the fleet-average values. Using this definition, approximately 5% of the LDGVs and HDDTs measured were high emitters. Among the 143 LDGVs, the average emission factors of NO(x), black carbon (BC), PM2.5, and ultrafine particle (UFP) would be reduced by 34%, 39%, 44%, and 31%, respectively, by removing the highest 5% of emitting vehicles, whereas CO emission factor would be reduced by 50%. The emission distributions of the 93 HDDTs measured were even more skewed: approximately half of the NO(x) and CO fleet-average emission factors and more than 60% of PM2.5, UFP, and BC fleet-average emission factors would be reduced by eliminating the highest-emitting 5% HDDTs. Furthermore, high emissions of BC, PM2.5, and NO(x) tended to cluster among the same vehicles. PMID:22070037

  1. 40 CFR Table N-1 to Subpart N of... - CO2 Emission Factors for Carbonate-Based Raw Materials

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false CO2 Emission Factors for Carbonate-Based Raw Materials N Table N-1 to Subpart N of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Glass Production...

  2. 40 CFR Table N-1 to Subpart N of... - CO2 Emission Factors for Carbonate-Based Raw Materials

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false CO2 Emission Factors for Carbonate-Based Raw Materials N Table N-1 to Subpart N of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Glass Production...

  3. 40 CFR Table N-1 to Subpart N of... - CO2 Emission Factors for Carbonate-Based Raw Materials

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false CO2 Emission Factors for Carbonate-Based Raw Materials N Table N-1 to Subpart N of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Glass Production...

  4. 40 CFR Table N-1 to Subpart N of... - CO2 Emission Factors for Carbonate-Based Raw Materials

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false CO2 Emission Factors for Carbonate-Based Raw Materials N Table N-1 to Subpart N of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Glass Production...

  5. 40 CFR 63.5890 - How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 13 2012-07-01 2012-07-01 false How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous lamination/casting operations? 63.5890 Section 63... demonstrate compliance for continuous lamination/casting operations? (a) Compliant line option. Use Equation...

  6. 40 CFR 63.5890 - How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 13 2014-07-01 2014-07-01 false How do I calculate an organic HAP emissions factor to demonstrate compliance for continuous lamination/casting operations? 63.5890 Section 63... demonstrate compliance for continuous lamination/casting operations? (a) Compliant line option. Use Equation...

  7. 40 CFR Table S-1 to Subpart S of... - Basic Parameters for the Calculation of Emission Factors for Lime Production

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Basic Parameters for the Calculation of Emission Factors for Lime Production S Table S-1 to Subpart S of Part 98 Protection of Environment... Manufacturing Pt. 98, Subpt. S, Table S-1 Table S-1 to Subpart S of Part 98—Basic Parameters for the...

  8. 40 CFR Table S-1 to Subpart S of... - Basic Parameters for the Calculation of Emission Factors for Lime Production

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Basic Parameters for the Calculation of Emission Factors for Lime Production S Table S-1 to Subpart S of Part 98 Protection of Environment... Manufacturing Pt. 98, Subpt. S, Table S-1 Table S-1 to Subpart S of Part 98—Basic Parameters for the...

  9. 40 CFR Table S-1 to Subpart S of... - Basic Parameters for the Calculation of Emission Factors for Lime Production

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Basic Parameters for the Calculation of Emission Factors for Lime Production S Table S-1 to Subpart S of Part 98 Protection of Environment... Manufacturing Pt. 98, Subpt. S, Table S-1 Table S-1 to Subpart S of Part 98—Basic Parameters for the...

  10. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4...

  11. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4...

  12. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4...

  13. 40 CFR Table K-1 to Subpart K of... - Electric Arc Furnace (EAF) CH4 Emission Factors

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Electric Arc Furnace (EAF) CH4 Emission Factors K Table K-1 to Subpart K of Part 98 Protection of Environment ENVIRONMENTAL PROTECTION.... 98, Subpt. K, Table K-1 Table K-1 to Subpart K of Part 98—Electric Arc Furnace (EAF) CH4...

  14. 40 CFR Table S-1 to Subpart S of... - Basic Parameters for the Calculation of Emission Factors for Lime Production

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Basic Parameters for the Calculation of Emission Factors for Lime Production S Table S-1 to Subpart S of Part 98 Protection of Environment... Manufacturing Pt. 98, Subpt. S, Table S-1 Table S-1 to Subpart S of Part 98—Basic Parameters for the...

  15. Factorization of air pollutant emissions: projections versus observed trends in Europe.

    PubMed

    Rafaj, Peter; Amann, Markus; Siri, José G

    2014-10-01

    This paper revisits the emission scenarios of the European Commission's 2005 Thematic Strategy on Air Pollution (TSAP) in light of today's knowledge. We review assumptions made in the past on the main drivers of emission changes, i.e., demographic trends, economic growth, changes in the energy intensity of GDP, fuel-switching, and application of dedicated emission control measures. Our analysis shows that for most of these drivers, actual trends have not matched initial expectations. Observed ammonia and sulfur emissions in European Union in 2010 were 10% to 20% lower than projected, while emissions of nitrogen oxides and particulate matter exceeded estimates by 8% to 15%. In general, a higher efficiency of dedicated emission controls compensated for a lower-than-expected decline in total energy consumption as well as a delay in the phase-out of coal. For 2020, updated projections anticipate lower sulfur and nitrogen oxide emissions than those under the 2005 baseline, whereby the degree to which these emissions are lower depends on what assumptions are made for emission controls and new vehicle standards. Projected levels of particulates are about 10% higher, while smaller differences emerge for other pollutants. New emission projections suggest that environmental targets established by the TSAP for the protection of human health, eutrophication and forest acidification will not be met without additional measures. PMID:25058894

  16. Factorization of air pollutant emissions: projections versus observed trends in Europe.

    PubMed

    Rafaj, Peter; Amann, Markus; Siri, José G

    2014-10-01

    This paper revisits the emission scenarios of the European Commission's 2005 Thematic Strategy on Air Pollution (TSAP) in light of today's knowledge. We review assumptions made in the past on the main drivers of emission changes, i.e., demographic trends, economic growth, changes in the energy intensity of GDP, fuel-switching, and application of dedicated emission control measures. Our analysis shows that for most of these drivers, actual trends have not matched initial expectations. Observed ammonia and sulfur emissions in European Union in 2010 were 10% to 20% lower than projected, while emissions of nitrogen oxides and particulate matter exceeded estimates by 8% to 15%. In general, a higher efficiency of dedicated emission controls compensated for a lower-than-expected decline in total energy consumption as well as a delay in the phase-out of coal. For 2020, updated projections anticipate lower sulfur and nitrogen oxide emissions than those under the 2005 baseline, whereby the degree to which these emissions are lower depends on what assumptions are made for emission controls and new vehicle standards. Projected levels of particulates are about 10% higher, while smaller differences emerge for other pollutants. New emission projections suggest that environmental targets established by the TSAP for the protection of human health, eutrophication and forest acidification will not be met without additional measures.

  17. Time evolution and emission factors of aerosol particles from day and night time savannah fires

    NASA Astrophysics Data System (ADS)

    Vakkari, Ville; Beukes, Johan Paul; Tiitta, Petri; Venter, Andrew; Jaars, Kerneels; Josipovic, Miroslav; van Zyl, Pieter; Kulmala, Markku; Laakso, Lauri

    2013-04-01

    number and size of particles larger than 100 nm; if this is not accounted for the current emission factors may underestimate the CCN-sized particle yield from savannah fires by a factor of two to three. Acknowledgements This research was supported by the Academy of Finland under the project Atmospheric monitoring capacity building in Southern Africa (project number 132640), by the Saastamoinen säätiö, by the North-West University and by the Academy of Finland Center of Excellence program (project number 1118615). References IPCC, Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2007. Pope, C. A., and Dockery, D. W.: Health effects of fine particulate air pollution: lines that connect, J Air Waste Manag. Assoc., 56, 709-742, 2006. Swap, R. J., Annegarn, H. J., Suttles, J. T., King, M. D., Platnick, S., Privette, J. L., and Scholes, R. J.: Africa burning: A thematic analysis of the Southern African Regional Science Initiative (SAFARI 2000), J. Geophys. Res., 108, 8465, doi:10.1029/2003JD003747, 2003. Vakkari, V., Beukes, J. P., Laakso, H., Mabaso, D., Pienaar, J. J., Kulmala, M., and Laakso, L.: Long-term observations of aerosol size distributions in semi-clean and polluted savannah in South Africa, Atmos. Chem. Phys. Discuss., 12, 24043-24093, doi:10.5194/acpd-12-24043-2012, 2012.

  18. Laboratory measurements of emission factors of nonmethane volatile organic compounds from burning of Chinese crop residues

    NASA Astrophysics Data System (ADS)

    Inomata, Satoshi; Tanimoto, Hiroshi; Pan, Xiaole; Taketani, Fumikazu; Komazaki, Yuichi; Miyakawa, Takuma; Kanaya, Yugo; Wang, Zifa

    2015-05-01

    The emission factors (EFs) of nonmethane volatile organic compounds (NMVOCs) emitted during the burning of Chinese crop residue were investigated as a function of modified combustion efficiency in laboratory experiments. NMVOCs, including acetonitrile, aldehydes/ketones, furan, and aromatic hydrocarbons, were monitored by proton-transfer-reaction mass spectrometry. Rape plant was burned in dry conditions and wheat straw was burned in both wet and dry conditions to simulate the possible burning of damp crop residue in regions of high temperature and humidity. We compared the present data to field data reported by Kudo et al. (2014). Good agreement between field and laboratory data was obtained for aromatics under relatively more smoldering combustion of dry samples, but laboratory data were slightly overestimated compared to field data for oxygenated VOC (OVOC). When EFs from the burning of wet samples were investigated, the consistency between the field and laboratory data for OVOCs was stronger than for dry samples. This may be caused by residual moisture in crop residue that has been stockpiled in humid regions. Comparison of the wet laboratory data with field data suggests that Kudo et al. (2014) observed the biomass burning plumes under relatively more smoldering conditions in which approximately a few tens of percentages of burned fuel materials were wet.

  19. [Lake algae chemotaxonomy technology based on fluorescence excitation emission matrix and parallel factor analysis].

    PubMed

    Chen, Xiao-Na; Han, Xiu-Rong; Su, Rong-Guo; Shi, Xiao-Yong

    2014-03-01

    An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor (PARAFAC) analysis and CHEMTAX. The PARAFAC model was applied to fluorescence excitation-emission matrix (EEM) of 23 algae species and 12 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. Based on the 12 fluorescent components, the algae species at different growth stages were correctly classified at the division level using Bayesian discriminant analysis (BDA). Then the reference fluorescent component ratio matrix was constructed for CHEMTAX, and the EEM-PARAFAC-CHEMTAX method was developed to differentiate taxonomic groups of algae. When the fluorometric method was used for 531 single-species samples, the average correct discrimination ratio (CDR) was 99.1% and the correct discrimination ratios (CDRs) were 100% at the division level except Chlorophyta, the CDR of which was 97.5%. The CDRs for 95 mixtures were above 98.5% for the dominant algae species and above 90.5% for the subdominant algae species, with average relative contents of 69.7% and 26.4%, respectively. This technique would be of great aid when low-cost and rapid analysis is needed for samples in a large batch.

  20. Static Structure Factor Effects on Theoretical Emissivity Profiles of Martian Surface Dust

    NASA Astrophysics Data System (ADS)

    Pitman, K. M.; Wolff, M. J.; Clayton, G. C.

    2003-05-01

    We continue our exploration of the behavior of Martian surface emissivity spectra in response to four fundamental particle microphysical properties (particle size, shape, surface roughness, and packing fraction) for micron-sized dust grains. In this work, we focus on the influence of the static structure factor [1, 2] on single-scattering albedo, particle scattering phase function, and asymmetry parameter for a variety of Mars-relevant effective grain radii in the thermal IR (TES, Odyssey) wavelength regime. By using modified single-scattering input parameters, we effectively use clusters of particles to determine reasonable packing fraction values for a theoretical planetary regolith. We compare our radiative transfer formulation to that of Mackowski's multisphere code (SCSMFO) [3]. The effects of packing fraction may also be examined experimentally by varying the compression of laboratory samples; we briefly discuss planned experiments. This work is supported through NASA MDAP (MJW) and LSU Board of Regents (KMP). [1] Mishchenko, M. I. (1994) JQSRT, 52, 1, 95-110. [2] Mishchenko, M. I., & Macke, A. (1997) JQSRT, 57, 1, 767-794. [3] Mackowski, D. W. (1994) J. Opt. Soc. Am. A, 11, 2851-2861.

  1. [Source emission characteristics and impact factors of volatile halogenated organic compounds from wastewater treatment plant].

    PubMed

    He, Jie; Wang, Bo-Guang; Liu, Shu-Le; Zhao, De-Jun; Tang, Xiao-Dong; Zou, Yu

    2011-12-01

    A low enrichment method of using Tenax as absorbent and liquid nitrogen as refrigerant has been established to sample the volatile halogenated organic compounds in Guangzhou Liede municipal wastewater treatment plant as well as its ambient air. The composition and concentration of target halogenated hydrocarbons were analyzed by combined thermal desorption/GC-MS to explore its sources profile and impact factors. The result showed that 19 halogenated organic compounds were detected, including 11 halogenated alkanets, 3 halogenated alkenes, 3 halogenated aromatic hydrocarbons and 2 haloesters, with their total concentrations ranged from 34.91 microg x m(-3) to 127.74 microg x m(-3) and mean concentrations ranged from n.d. to 33.39 microg x m(-3). Main pollutants of the studied plant were CH2Cl2, CHCl3, CFC-12, C2H4Cl2, CFC-11, C2HCl3 and C2Cl4, they came from the wastewater by volatilization. Among the six processing units, the dehydration room showed the highest level of halogenated organic compounds, followed by pumping station, while the sludge thickener was the lowest. The emissions from pumping station, aeration tank and biochemical pool were significantly affected by temperature and humidity of environment.

  2. GHG emission factors developed for the collection, transport and landfilling of municipal waste in South African municipalities.

    PubMed

    Friedrich, Elena; Trois, Cristina

    2013-04-01

    Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5 dm(3) (litres) per tonne of wet waste and the associated GHG emissions are about 15 kg CO2 equivalents (CO2 e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from -145 to 1016 kg CO2 e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532 kg CO2 e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement. Other low cost avenues need to be investigated to suit local conditions, in particular landfill covers which enhance methane oxidation. PMID:23312780

  3. GHG emission factors developed for the collection, transport and landfilling of municipal waste in South African municipalities.

    PubMed

    Friedrich, Elena; Trois, Cristina

    2013-04-01

    Greenhouse gas (GHG) emission factors are used with increased frequency for the accounting and reporting of GHG from waste management. However, these factors have been calculated for developed countries of the Northern Hemisphere and are lacking for developing countries. This paper shows how such factors have been developed for the collection, transport and landfilling of municipal waste in South Africa. As such it presents a model on how international results and methodology can be adapted and used to calculate country-specific GHG emission factors from waste. For the collection and transport of municipal waste in South Africa, the average diesel consumption is around 5 dm(3) (litres) per tonne of wet waste and the associated GHG emissions are about 15 kg CO2 equivalents (CO2 e). Depending on the type of landfill, the GHG emissions from the landfilling of waste have been calculated to range from -145 to 1016 kg CO2 e per tonne of wet waste, when taking into account carbon storage, and from 441 to 2532 kg CO2 e per tonne of wet waste, when carbon storage is left out. The highest emission factor per unit of wet waste is for landfill sites without landfill gas collection and these are the dominant waste disposal facilities in South Africa. However, cash strapped municipalities in Africa and the developing world will not be able to significantly upgrade these sites and reduce their GHG burdens if there is no equivalent replacement of the Clean Development Mechanism (CDM) resulting from the Kyoto agreement. Other low cost avenues need to be investigated to suit local conditions, in particular landfill covers which enhance methane oxidation.

  4. Seasonal Variation and Ecosystem Dependence of Emission Factors for Selected Trace Gases and PM2.5 for Southern African Savanna Fires

    NASA Technical Reports Server (NTRS)

    Korontzi, S.; Ward, D. E.; Susott, R. A.; Yokelson, R. J.; Justice, C. O.; Hobbs, P. V.; Smithwick, E. A. H.; Hao, W. M.

    2003-01-01

    In this paper we present the first early dry season (early June-early August) emission factor measurements for carbon dioxide (CO2), carbon monoxide (CO), methane (Ca), nonmethane hydrocarbons (NMHC), and particulates with a diameter less than 2.5 microns (pM2.5) for southern African grassland and woodland fires. Seasonal emission factors for grassland fires correlate linearly with the proportion of green grass, used as a surrogate for the fuel moisture content, and are higher for products of incomplete combustion in the early part of the dry season compared with later in the dry season. Models of emission factors for NMHC and PM(sub 2.5) versus modified combustion efficiency (MCE) are statistically different in grassland compared with woodland ecosystems. We compare predictions based on the integration of emissions factors from this study, from the southern African Fire-Atmosphere Research Initiative 1992 (SAFARI-92), and from SAFARI-2000 with those based on the smaller set of ecosystem-specific emission factors to estimate the effects of using regional-average rather than ecosystem-specific emission factors. We also test the validity of using the SAFARI-92 models for emission factors versus MCE to predict the early dry season emission factors measured in this study. The comparison indicates that the largest discrepancies occur at the low end (0.907) and high end (0.972) of MCE values measured in this study. Finally, we combine our models of MCE versus proportion of green grass for grassland fires with emission factors versus MCE for selected oxygenated volatile organic compounds measured in the SAFARI-2000 campaign to derive the first seasonal emission factors for these compounds. The results of this study demonstrate that seasonal variations in savanna fire emissions are important and should be considered in modeling emissions at regional to continental scales.

  5. State-level Greenhouse Gas Emission Factors for Electricity Generation, Updated

    EIA Publications

    2001-01-01

    To assist reporters in estimating emissions and emission reductions, The Energy Information Administration (EIA) has made available in the instructions to Forms EIA-1605 and EIA-1605EZ emission coefficients for most commonly used fossil fuels and electricity. These coefficients were based on 1992 emissions and generation data. In 1999, updated coefficients were prepared based on the most recent data (1998) then available; however, the updated coefficients were not included in the instructions for the 1999 data year. This year, they have been updated again, but based on three years worth of data (1997, 1998, and 1999) rather than a single year.

  6. Development of Hot Exhaust Emission Factors for Iranian-Made Euro-2 Certified Light-Duty Vehicles.

    PubMed

    Banitalebi, Ehsan; Hosseini, Vahid

    2016-01-01

    Emission factors (EFs) are fundamental, necessary data for air pollution research and scenario implementation. With the vision of generating national EFs of the Iranian transportation system, a portable emission measurement system (PEMS) was used to develop the basic EFs for a statistically significant sample of Iranian gasoline-fueled privately owned light duty vehicles (LDVs) operated in Tehran. A smaller sample size of the same fleet was examined by chassis dynamometer (CD) bag emission measurement tests to quantify the systematic differences between the PEMS and CD methods. The selected fleet was tested over four different routes of uphill highways, flat highways, uphill urban streets, and flat urban streets. Real driving emissions (RDEs) and fuel consumption (FC) rates were calculated by weighted averaging of the results from each route. The activity of the fleet over each route type was assumed as a weighting factor. The activity data were obtained from a Tehran traffic model. The RDEs of the selected fleet were considerably higher than the certified emission levels of all vehicles. Differences between Tehran real driving cycles and the New European Driving Cycle (NEDC) was attributed to the lower loading of NEDC. A table of EFs based on RDEs was developed for the sample fleet.

  7. Two showy traits, scent emission and pigmentation, are finely coregulated by the MYB transcription factor PH4 in petunia flowers.

    PubMed

    Cna'ani, Alon; Spitzer-Rimon, Ben; Ravid, Jasmin; Farhi, Moran; Masci, Tania; Aravena-Calvo, Javiera; Ovadis, Marianna; Vainstein, Alexander

    2015-11-01

    The mechanism underlying the emission of phenylpropanoid volatiles is poorly understood. Here, we reveal the involvement of PH4, a petunia MYB-R2R3 transcription factor previously studied for its role in vacuolar acidification, in floral volatile emission. We used the virus-induced gene silencing (VIGS) approach to knock down PH4 expression in petunia, measured volatile emission and internal pool sizes by GC-MS, and analyzed transcript abundances of scent-related phenylpropanoid genes in flowers. Silencing of PH4 resulted in a marked decrease in floral phenylpropanoid volatile emission, with a concurrent increase in internal pool levels. Expression of scent-related phenylpropanoid genes was not affected. To identify putative scent-related targets of PH4, we silenced PH5, a tonoplast-localized H(+) -ATPase that maintains vacuolar pH homeostasis. Suppression of PH5 did not yield the reduced-emission phenotype, suggesting that PH4 does not operate in the context of floral scent through regulation of vacuolar pH. We conclude that PH4 is a key floral regulator that integrates volatile production and emission processes and interconnects two essential floral traits - color and scent.

  8. A new approach to in-situ determination of roadside particle emission factors of individual vehicles under conventional driving conditions

    NASA Astrophysics Data System (ADS)

    Hak, Claudia S.; Hallquist, Mattias; Ljungström, Evert; Svane, Maria; Pettersson, Jan B. C.

    A method for continuous on-road measurements of particle number emissions for both diesel- and petrol-fuelled vehicles is presented. The setup allows the determination of particle number emission factors on an individual vehicle basis by the simultaneous measurement of CO 2 and particle concentrations. As an alternative to previous measurements on the kerbside, the sample is taken directly in the street, with the advantage of sampling in-situ within the exhaust plumes of passing vehicles, allowing the separation of the individual high-concentration plumes. The method was tested in two experiments that were conducted in the Gothenburg area. In the first study, which was performed at an urban roadside, we were able to determine particle emission factors from individual vehicles in a common car fleet passing the measurement site. The obtained emission factors were of the same order of magnitude (between 1.4 × 10 12 and 1.8 × 10 14 particles km -1) as values published in the recent literature for light duty vehicles. An additional on-road experiment was conducted at a rural road with four light duty reference vehicles (three of them petrol-powered and one diesel-powered) at driving speeds of 50 and 70 km h -1, realised with different engine speeds. The results of the traffic emission studies show that the method is applicable provided that instruments with an adequate dynamic range are used and that the traffic is not too dense. In addition, the variability in particle emissions for a specified driving condition was estimated.

  9. Factors Influencing Greenhouse Gas Emissions from Three Gorges Reservoir of China

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Zhao, X.; Wu, B.; Zeng, Y.

    2013-05-01

    Three gorges reservoir (TGR) of China located in a subtropical climate region. It has attracted tremendous attentions on greenhouse gas (GHG) emissions from TGR, including carbon dioxide (CO2), methane (CH4) and nitrous Oxide (N2O). Results on monthly fluxes and their spatial and seasonal variations have been determined by a static chamber method and have published elsewhere recently. Here we made further discussions on the factors influencing GHG emissions from TGR. We conclude that the hydrodynamic situation was the key parameter controlling the fluxes. TGR was a typical valley-type reservoir and with a complex terrain in the surrounding catchment, where almost 94% of the region was occupied by mountainous, this situation made the reservoir had sufficient allochthonous organic carbon input origin from eroded soil. But no significant relationship between organic carbon (both dissolved and particulate form) and GHG fluxes, we thought that TGR was not a carbon-limited reservoir on the GHG issue. In the mainstream of the reservoir, dissolved CO2 and CH4 were supersaturation in the water, the relative high flow together with the narrow-deep channel result in great disturbance, which would promote more dissolved gas escape into the atmosphere. This could also approved by the differences in CO2 and CH4 fluxes in different reach from up to downstream of the reservoir. In the reservoir tail water, the mainstream remained the high flow rate, both CO2 and CH4 fluxes is relative high, while downwards, the fluxes were gradually dropped, as after the impoundment of the reservoir, flow rate have greatly decreased. Another evidence was the relative higher CO2 and CH4 fluxes in the rainy season. As the rainy season approaches, TGR would empty the storage to prepare for retention and mitigation. The interplay between water inflows and outflows produced marked variations in the water residence times. During the rainy season times, this could be as short as 6 days with higher water

  10. A Comparison of Inventoried and Measured U.S. Urban/Industrial Hg Emission Factors during the NOMADSS Experiment

    NASA Astrophysics Data System (ADS)

    Ambrose, J. L., II; Gratz, L.; Jaffe, D. A.; Apel, E. C.; Campos, T. L.; Flocke, F. M.; Guenther, A. B.; Hornbrook, R. S.; Karl, T.; Kaser, L.; Knapp, D. J.; Weinheimer, A. J.; Cantrell, C. A.; Mauldin, L.; Yuan, B.

    2014-12-01

    We performed an airborne survey of some large anthropogenic mercury (Hg) emission sources in the Southeast U.S. during the 2013 Nitrogen, Oxidants, Mercury and Aerosol Distribution, Sources, and Sinks (NOMADSS) experiment. The observations included speciated atmospheric Hg, and tracers of urban/industrial emissions and associated photochemistry (e.g., carbon monoxide, CO; carbon dioxide, CO2; sulfur dioxide, SO2; nitrogen oxides (NOx); volatile organic compounds, VOCs; ozone, O3; hydroxyl radical, HO·; sulfuric acid, H2SO4) and were made from the National Science Foundation's/National Center for Atmospheric Research's C-130 research aircraft. Mercury was measured using the University of Washington's Detector for Oxidized Hg Species. We derived Hg emission factors (EF) for several U.S. urban areas and large industrial point sources, including coal-fired power plants (CFPPs) in Louisiana, Pennsylvania, Texas, and West Virginia. We compared our measured Hg EFs with inventory-based values from two separate Hg emission inventories provided by the U.S. Environmental Protection Agency - the National Emissions Inventory (NEI) and the Toxics Release Inventory (TRI). We also performed an inter-comparison of the inventory-based Hg EFs. For the CFPPs sampled, we find that actual Hg emissions differed from inventoried values by more than a factor of two in some cases. Measured Hg EFs were weakly correlated with values reported in the NEI: m = 0.71; r2 = 0.47 (p = 0.06; n = 8), whereas EFs derived from the TRI were not meaningfully predictive of the measured values: m = -3.3; r2 = 0.61 (p < 0.05; n = 8). Median absolute differences between measured and inventory-based EFs were ≥50%, relative to the inventory values. The median absolute average difference between the Hg EFs reported in the two inventories was approximately 40%. Our results place quantitative constraints on uncertainties associated with the inventoried Hg emissions. Additionally, our results suggest that the

  11. METHANE EMISSIONS FROM THE NATURAL GAS INDUSTRY VOLUME 5: ACTIVITY FACTORS

    EPA Science Inventory

    The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...

  12. Battery condenser system total particulate emission factors and rates for cotton gins: Method 17

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  13. Battery condenser system PM10 emission factors and rates for cotton gins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is part of a series of manuscripts that to characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study ...

  14. Battery condenser system total particulate emission factors and rates for cotton gins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  15. RERANKING OF AREA SOURCES IN LIGHT OF SEASONAL/ REGIONAL EMISSION FACTORS AND STATE/LOCAL NEEDS

    EPA Science Inventory

    The report gives results of an effort to provide a better understanding of air pollution area sources and their emissions, to prioritize their importance as emitters of volatile organic compounds (VOCs), and to identify sources for which better emission estimation methodologies a...

  16. Mote trash system total particulate emission factors and rates for cotton gins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was...

  17. Regulation of biosynthesis and emission of volatile phenylpropanoids/benzenoids in petunia× hybrida flowers by multi-factors of circadian clock, light, and temperature.

    PubMed

    Cheng, Sihua; Fu, Xiumin; Mei, Xin; Zhou, Ying; Du, Bing; Watanabe, Naoharu; Yang, Ziyin

    2016-10-01

    Floral volatile phenylpropanoids and benzenoids (VPBs) play important ecological functions and have potential economic applications. Little is known about how multi-factors in integration regulate the formation and emission of floral VPBs. In the present study, we investigated effects of multi factors including endogenous circadian clock, light, and temperature on the formation and emission of VPBs, which are major volatiles in flowers of Petunia× hybrida cv. 'Mitchell Diploid'. Endogenous circadian clock was proposed as the most important factor regulating rhythmic emission of VPBs and expressions of structural genes involved in the upstream biosynthetic pathway of VPBs, but did not affect expression levels of structural genes involved in the downstream pathway and VPBs-related regulators. In contrast to light, temperature was a more constant factor affecting emission of VPBs. VPBs emission could be inhibited within a short time by increasing temperature. The information will contribute to our understanding of emission mechanism of floral volatiles. PMID:27235646

  18. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  19. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  20. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  1. 40 CFR Table Aa-1 to Subpart Aa of... - Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Kraft Pulping Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O AA Table AA-1 to Subpart AA of Part 98 Protection of Environment... Liquor Emissions Factors for Biomass-Based CO2, CH4, and N2O Wood furnish Biomass-based emissions...

  2. 40 CFR Table Aa-2 to Subpart Aa of... - Kraft Lime Kiln and Calciner Emissions Factors for CH4 and N2O

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Kraft Lime Kiln and Calciner Emissions... Manufacturing Pt. 98, Subpt. AA, Table AA -2 Table AA-2 to Subpart AA of Part 98—Kraft Lime Kiln and Calciner Emissions Factors for CH4 and N2O Fuel Fossil fuel-based emissions factors (kg/mmBtu HHV) Kraft lime...

  3. 40 CFR Table W - 1A of Subpart W-Default Whole Gas Emission Factors for Onshore Petroleum and Natural Gas Production

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Factors for Onshore Petroleum and Natural Gas Production W Table W Protection of Environment... Petroleum and Natural Gas Systems Definitions. Pt. 98, Subpt. W, Table W-1A Table W-1A of Subpart W—Default Whole Gas Emission Factors for Onshore Petroleum and Natural Gas Production Onshore petroleum...

  4. 40 CFR 63.5796 - What are the organic HAP emissions factor equations in Table 1 to this subpart, and how are they...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... factor equations in Table 1 to this subpart, and how are they used in this subpart? 63.5796 Section 63... emissions factor equations in Table 1 to this subpart, and how are they used in this subpart? Emissions... Tables 3 and 5 to this subpart. You may use the equations in Table 1 to this subpart to calculate...

  5. 40 CFR Table Jj-7 to Subpart Jj of... - Nitrous Oxide Emission Factors (kg N2O-N/kg Kjdl N)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Nitrous Oxide Emission Factors (kg N2O-N/kg Kjdl N) JJ Table JJ-7 to Subpart JJ of Part 98 Protection of Environment ENVIRONMENTAL... N2O-N/kg Kjdl N) Manure management system component N2O emission factor Uncovered anaerobic lagoon...

  6. Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, northeast China

    USGS Publications Warehouse

    Olsson, Linda; Ye, Siyuan; Yu, Xueyang; Wei, Mengjie; Krauss, Ken W.; Brix, Hans

    2015-01-01

    Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on CH4 emissions and ecosystem respiration (Reco) from five coastal wetlands in the Liaohe Delta, northeast China: two Phragmites australis (common reed) wetlands, two Suaeda salsa (sea blite) marshes and a rice (Oryza sativa) paddy. Throughout the growing season, the Suaeda wetlands were net CH4 sinks whereas the Phragmites wetlands and the rice paddy were net CH4sources emitting 1.2–6.1 g CH4 m−2 y−1. The Phragmites wetlands emitted the most CH4 per unit area and the most CH4 relative to CO2. The main controlling factors for the CH4 emissions were water table, temperature and salinity. The CH4 emission was accelerated at high and constant (or managed) water tables and decreased at water tables below the soil surface. High temperatures enhanced CH4 emissions, and emission rates were consistently low (< 1 mg CH4 m−2 h) at soil temperatures <18 °C. At salinity levels > 18 ppt, the CH4 emission rates were always low (< 1 mg CH4 m−2 h−1) probably because methanogens were outcompeted by sulphate reducing bacteria. Saline Phragmites wetlands can, however, emit significant amounts of CH4 as CH4 produced in deep soil layers are transported through the air-space tissue of the plants to the atmosphere. The CH4 emission from coastal wetlands can be reduced by creating fluctuating water tables, including water tables below the soil surface, as well as by occasional flooding by high-salinity water. The effects of water management schemes on the biological communities in the wetlands must, however, be carefully studied prior to the management in order to avoid undesirable effects on the wetland communities.

  7. Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, Northeast China

    NASA Astrophysics Data System (ADS)

    Olsson, L.; Ye, S.; Yu, X.; Wei, M.; Krauss, K. W.; Brix, H.

    2015-08-01

    Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on CH4 emissions and ecosystem respiration (Reco) from five coastal wetlands in the Liaohe Delta, Northeast China: two Phragmites australis (common reed) wetlands, two Suaeda salsa (sea blite) marshes and a rice (Oryza sativa) paddy. Throughout the growing season, the Suaeda wetlands were net CH4 sinks whereas the Phragmites wetlands and the rice paddy were net CH4 sources emitting 1.2-6.1 g CH4 m-2 yr-1. The Phragmites wetlands emitted the most CH4 per unit area and the most CH4 relative to CO2. The main controlling factors for the CH4 emissions were water table, temperature, soil organic carbon and salinity. The CH4 emission was accelerated at high and constant (or managed) water tables and decreased at water tables below the soil surface. High temperatures enhanced CH4 emissions, and emission rates were consistently low (< 1 mg CH4 m-2 h-1) at soil temperatures < 18 °C. At salinity levels > 18 ppt, the CH4 emission rates were always low (< 1 mg CH4 m-2 h-1) probably because methanogens were out-competed by sulphate-reducing bacteria. Saline Phragmites wetlands can, however, emit significant amounts of CH4 as CH4 produced in deep soil layers are transported through the air-space tissue of the plants to the atmosphere. The CH4 emission from coastal wetlands can be reduced by creating fluctuating water tables, including water tables below the soil surface, as well as by occasional flooding by high-salinity water. The effects of water management schemes on the biological communities in the wetlands must, however, be carefully studied prior to the management in order to avoid undesirable effects on the wetland communities.

  8. Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, Northeast China

    NASA Astrophysics Data System (ADS)

    Olsson, L.; Ye, S.; Yu, X.; Wei, M.; Krauss, K. W.; Brix, H.

    2015-02-01

    Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on CH4 emissions and ecosystem respiration (Reco) from five coastal wetlands in the Liaohe Delta, northeast China: two Phragmites australis (common reed) wetlands, two Suaeda salsa (sea blite) marshes and a rice (Oryza sativa) paddy. Throughout the growing season, the Suaeda wetlands were net CH4 sinks whereas the Phragmites wetlands and the rice paddy were net CH4 sources emitting 1.2-6.1 g CH4 m-2 y-1. The Phragmites wetlands emitted the most CH4 per unit area and the most CH4 relative to CO2. The main controlling factors for the CH4 emissions were water table, temperature and salinity. The CH4 emission was accelerated at high and constant (or managed) water tables and decreased at water tables below the soil surface. High temperatures enhanced CH4 emissions, and emission rates were consistently low (< 1 mg CH4 m-2 h) at soil temperatures <18 °C. At salinity levels > 18 ppt, the CH4 emission rates were always low (< 1 mg CH4 m-2 h-1) probably because methanogens were outcompeted by sulphate reducing bacteria. Saline Phragmites wetlands can, however, emit significant amounts of CH4 as CH4 produced in deep soil layers are transported through the air-space tissue of the plants to the atmosphere. The CH4 emission from coastal wetlands can be reduced by creating fluctuating water tables, including water tables below the soil surface, as well as by occasional flooding by high-salinity water. The effects of water management schemes on the biological communities in the wetlands must, however, be carefully studied prior to the management in order to avoid undesirable effects on the wetland communities.

  9. Were mercury emission factors for Chinese non-ferrous metal smelters overestimated? Evidence from onsite measurements in six smelters.

    PubMed

    Zhang, Lei; Wang, Shuxiao; Wu, Qingru; Meng, Yang; Yang, Hai; Wang, Fengyang; Hao, Jiming

    2012-12-01

    Non-ferrous metal smelting takes up a large proportion of the anthropogenic mercury emission inventory in China. Zinc, lead and copper smelting are three leading sources. Onsite measurements of mercury emissions were conducted for six smelters. The mercury emission factors were 0.09-2.98 g Hg/t metal produced. Acid plants with the double-conversion double-absorption process had mercury removal efficiency of over 99%. In the flue gas after acid plants, 45-88% was oxidized mercury which can be easily scavenged in the flue gas scrubber. 70-97% of the mercury was removed from the flue gas to the waste water and 1-17% to the sulfuric acid product. Totally 0.3-13.5% of the mercury in the metal concentrate was emitted to the atmosphere. Therefore, acid plants in non-ferrous metal smelters have significant co-benefit on mercury removal, and the mercury emission factors from Chinese non-ferrous metal smelters were probably overestimated in previous studies.

  10. Derivation of greenhouse gas emission factors for peatlands managed for extraction in the Republic of Ireland and the United Kingdom

    NASA Astrophysics Data System (ADS)

    Wilson, D.; Dixon, S. D.; Artz, R. R. E.; Smith, T. E. L.; Evans, C. D.; Owen, H. J. F.; Archer, E.; Renou-Wilson, F.

    2015-09-01

    Drained peatlands are significant hotspots of carbon dioxide (CO2) emissions and may also be more vulnerable to fire with its associated gaseous emissions. Under the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, greenhouse gas (GHG) emissions from peatlands managed for extraction are reported on an annual basis. However, the Tier 1 (default) emission factors (EFs) provided in the IPCC 2013 Wetlands Supplement for this land use category may not be representative in all cases and countries are encouraged to move to higher-tier reporting levels with reduced uncertainty levels based on country- or regional-specific data. In this study, we quantified (1) CO2-C emissions from nine peat extraction sites in the Republic of Ireland and the United Kingdom, which were initially disaggregated by land use type (industrial versus domestic peat extraction), and (2) a range of GHGs that are released to the atmosphere with the burning of peat. Drainage-related methane (CH4) and nitrous oxide (N2O) emissions as well as CO2-C emissions associated with the off-site decomposition of horticultural peat were not included here. Our results show that net CO2-C emissions were strongly controlled by soil temperature at the industrial sites (bare peat) and by soil temperature and leaf area index at the vegetated domestic sites. Our derived EFs of 1.70 (±0.47) and 1.64 (±0.44) t CO2-C ha-1 yr-1 for the industrial and domestic sites respectively are considerably lower than the Tier 1 EF (2.8 ± 1.7 t CO2-C ha-1 yr-1) provided in the Wetlands Supplement. We propose that the difference between our derived values and the Wetlands Supplement value is due to differences in peat quality and, consequently, decomposition rates. Emissions from burning of the peat (g kg-1 dry fuel burned) were estimated to be approximately 1346 CO2, 8.35 methane (CH4), 218 carbon monoxide (CO), 1.53 ethane (C2H6), 1.74 ethylene (C2H4), 0.60 methanol (CH3OH), 2.21 hydrogen

  11. Distortion product otoacoustic emissions as a prognostic factor for idiopathic sudden sensorineural hearing loss.

    PubMed

    Chao, Ting-Kuang; Chen, Tony Hsiu-Hsi

    2006-01-01

    We investigated distortion product otoacoustic emissions (DPOAE) as a prognostic factor in idiopathic sudden sensorineural hearing loss (ISSHL) patients with the time-dependent Cox proportional-hazards model. We also compared the importance of the prognostic factors that are reported in the literature. 108 patients with ISSHL were included. Both DPOAE and pure tone audiometry were performed everyday for a maximum of 7 days during admission and followed every other week or monthly after discharge. All DPOAE amplitudes were analyzed at 2f1-f2--namely 1093, 1375, 1750, 2187, 2781, 3500, 4375, and 5500 Hz. The average of two series of DPOAE intensity corrected for the noise level in eight frequencies was coded as dichotomous at > or =6 or <6 dB. We selected the most updated DPOAE at 3 days or more before the assessment of recovery into the analysis. The potential confounders including age, sex, history of vertigo at onset, history of hypertension, diabetes, coronary arterial disease, and stroke, configuration and severity of initial pure tone audiometry, the duration from onset to treatment, auditory brainstem response (ABR), vestibular evoked myogenic potential (VEMP), and plasma triglyceride and cholesterol levels, hemoglobin level, and erythrocyte sedimentation rate were collected for evaluation. The results showed that a better DPOAE amplitude was a significantly good prognostic indicator both in univariate analysis (recovery rate ratio = 3.626, 95% CI = 2.119-6.205, p < 0.0001) and multivariate analysis (recovery rate ratio = 2.94, 95% CI = 1.537-5.624, p = 0.0011). The Kaplan-Meier estimates showed that the younger age group (< or =40 years) with better initial pure tone audiometry (<65 dB) represented a better prognosis that was compatible with previous literature (log-rank test, p = 0.0297 and p = 0.0019 respectively). In the univariate analysis, normal ABR and VEMP waveforms were associated with a better prognosis (ABR: recovery rate ratio = 2.984, 95% CI = 1

  12. Fugitive Dust Emission Factors for Puff and Mobile Military Sources Measured by Micro-pulse Lidar - A Summary of Results

    NASA Astrophysics Data System (ADS)

    Yuen, W.; Du, K.; Rood, M. J.; Kemme, M. R.; Kim, B.; Hashmonay, R. A.

    2010-12-01

    A summary of the development of a novel optical remote sensing (ORS) method that determined fugitive dust emission factors for unique military activities is described for puff and mobile sources. Four field campaigns characterized artillery back blasts as puff sources (M549A1 and M107), and movement of military vehicles (M1A1, M113, Bradley Fighting Vehicle (BFV), M88, M270, M577, and HEMTT) and an airborne helicopter (Bell 210) as mobile sources. The ORS method includes a Micro-Pulse Lidar (MPL) and a reflective target that determines one-dimensional (1-D) light extinction coefficient profiles. The MPL was mounted on a positioner that allows the MPL to automatically scan vertically, which allowed 1-D extinction coefficient profiles to be measured at select angles from horizontal. Two-dimensional (2-D) light extinction coefficient profiles were then determined by interpolating the 1-D extinction profiles measured at select angles. Dust property, in the form of the mass extinction efficiency (MEE), was measured using Open Path- Fourier Transform Infrared Spectrometry (OP-FTIR) and Open Path- Laser Transmissometry (OP-LT) in the first three field campaigns and an OP-LT and DustTrak™ in the fourth field campaign. MEE was used to convert the 2-D light extinction coefficient profiles to 2-D dust mass concentration profiles. Emission factors were determined by integrating the 2-D mass concentration profiles with measured wind vectors. Results from these field campaigns show that: 1) artillery with stronger recoiling forces generates more fugitive dust; 2) the dust emission factors for tracked vehicles are correlated with vehicle momentum; 3) emission factor decreases with increasing speed for airborne helicopters; and 4) wheeled vehicles (HEMTT) generate more fugitive dust than tracked vehicles (M88, M270, M577).

  13. Size-Resolved Particle Number and Volume Emission Factors for On-Road Gasoline and Diesel Motor Vehicles

    SciTech Connect

    Ban-Weiss, George A.; Lunden, Melissa M.; Kirchstetter, Thomas W.; Harley, Robert A.

    2009-04-10

    Average particle number concentrations and size distributions from {approx}61,000 light-duty (LD) vehicles and {approx}2500 medium-duty (MD) and heavy-duty (HD) trucks were measured during the summer of 2006 in a San Francisco Bay area traffic tunnel. One of the traffic bores contained only LD vehicles, and the other contained mixed traffic, allowing pollutants to be apportioned between LD vehicles and diesel trucks. Particle number emission factors (particle diameter D{sub p} > 3 nm) were found to be (3.9 {+-} 1.4) x 10{sup 14} and (3.3 {+-} 1.3) x 10{sup 15} kg{sup -1} fuel burned for LD vehicles and diesel trucks, respectively. Size distribution measurements showed that diesel trucks emitted at least an order of magnitude more particles for all measured sizes (10 < D{sub p} < 290 nm) per unit mass of fuel burned. The relative importance of LD vehicles as a source of particles increased as D{sub p} decreased. Comparing the results from this study to previous measurements at the same site showed that particle number emission factors have decreased for both LD vehicles and diesel trucks since 1997. Integrating size distributions with a volume weighting showed that diesel trucks emitted 28 {+-} 11 times more particles by volume than LD vehicles, consistent with the diesel/gasoline emission factor ratio for PM{sub 2.5} mass measured using gravimetric analysis of Teflon filters, reported in a companion paper.

  14. Semi-Volatile and Particulate Polycyclic Aromatic Hydrocarbons inEnvironmental Tobacco Smoke: Cleanup, Speciation and EmissionsFactors

    SciTech Connect

    Gundel, L.A.; Mahanama, K.R.R.; Daisey, J.M.

    1995-02-01

    Studies of phase distributions and emission factors for polycyclic aromatic hydrocarbons (PAH) in environmental tobacco smoke (ETS) require collection and analysis of very small samples. To achieve the necessary selectivity and sensitivity, a method has been devised and tested for extraction and cleanup of gas- and particulate-phase ETS samples. Gas-phase species were trapped by polymeric sorbents, and particles were trapped on filters. The samples were extracted with hot cyclohexane, concentrated and passed through silica solid-phase extraction columns for cleanup. After solvent change, the PAH were determined by high performance liquid chromatography with two programmed fluorescence detectors. PAH concentrations in 15-mg aliquots of National Institute of Standards and Technology Standard Reference Material SRM 1649 (Urban DustIOrganics) agreed well with published values. Relative precision at the 95% confidence level was 8% for SRM 1649 and 20% for replicate samples (5 mg) of ETS particles. Emission factors have been measured for a range of gas- and particulate-phase polycyclic aromatic hydrocarbons in ETS. The emission factors per cigarette were 13.0{+-}0.5 mg particulate matter, 11.2{+-}0.9 pg for gas-phase naphthalene and 74{+-}10 {micro}g for particulate benzo(a)pyrene.

  15. Open-path Emission Factors Derived from DOAS and FTIR Measurements in the Mexico City Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Flores, E.; Grutter, M.; Galle, B.; Mellqvist, J.; Samuelsson, J.; Knighton, B.; Jobson, B. T.; Volkamer, R.; Molina, L. T.; Molina, M. J.

    2004-12-01

    Mobile sources are responsible for about 50% of VOC (volatile organic compounds) and about 70% of NOx emissions in the Mexico City Metropolitan Area (MCMA). A novel approach has been developed to derive emission factors for mobile sources that are representative of the overall vehicle fleet, using collocated open-path Differential Optical Absorption Spectroscopy (DOAS) and Fourier Transform Infrared (FTIR) spectroscopic measurements. Measurements were recorded at two sites within the MCMA: (1) research-grade DOAS and FTIR systems were operated at the Mexican National Research and Training Center (CENICA) in Iztapalapa, (2) a research grade FTIR was operated at La Merced. In addition, point-sampling with a proton transfer reaction mass spectrometer (PTR-MS) was performed on the same location and the calibration standards for the PTR-MS and the DOAS instruments were cross-calibrated. The DOAS measured speciated aromatic hydrocarbons, including benzene, toluene, m-xylene, p-xylene, ethylbenzene (and mono-substituted alkylbenzenes), benzaldehyde, phenol, and p-cresol. The DOAS detection of aromatic hydrocarbons in the UV/vis spectral range between 250 to 310 nm suffers from the interference of molecular oxygen, and a novel approach is being presented that enables measurement of absolute concentrations of the above species. Further, HONO, NO2, SO2 and HCHO were measured at longer wavelengths. In combination with FTIR measurements of CO, CO2, NO, HCHO, ethylene, ethene, and total alkane, average emission factors for NOx, SO2 and numerous hydrocarbons were derived and scaled with fuel sales data to estimate total emissions of the vehicle fleet in the MCMA. The advantages and limitations of this low-cost emission inventory for mobile sources are decsribed.

  16. Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part II. CO, HC and NOx.

    PubMed

    Huang, Xiaoyan; Wang, Yang; Xing, Zhenyu; Du, Ke

    2016-09-15

    The estimation of emission factors (EFs) is the basis of accurate emission inventory. However, the EFs of air pollutants for motor vehicles vary under different operating conditions, which will cause uncertainty in developing emission inventory. Natural gas (NG), considered as a "cleaner" fuel than gasoline, is increasingly being used to reduce combustion emissions. However, information is scarce about how much emission reduction can be achieved by motor vehicles burning NG (NGVs) under real road driving conditions, which is necessary for evaluating the environmental benefits for NGVs. Here, online, in situ measurements of the emissions from nine bi-fuel vehicles were conducted under different operating conditions on the real road. A comparative study was performed for the EFs of black carbon (BC), carbon monoxide (CO), hydrocarbons (HCs) and nitrogen oxides (NOx) for each operating condition when the vehicles using gasoline and compressed NG (CNG) as fuel. BC EFs were reported in part I. The part II in this paper series reports the influence of operating conditions and fuel types on the EFs of CO, HC and NOx. Fuel-based EFs of CO showed good correlations with speed when burning CNG and gasoline. The correlation between fuel-based HC EFs and speed was relatively weak whether burning CNG or gasoline. The fuel-based NOx EFs moderately correlated with speed when burning CNG, but weakly correlated with gasoline. As for HC, the mileage-based EFs of gasoline vehicles are 2.39-12.59 times higher than those of CNG vehicles. The mileage-based NOx EFs of CNG vehicles are slightly higher than those of gasoline vehicles. These results would facilitate a detailed analysis of the environmental benefits for replacing gasoline with CNG in light duty vehicles.

  17. Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part II. CO, HC and NOx.

    PubMed

    Huang, Xiaoyan; Wang, Yang; Xing, Zhenyu; Du, Ke

    2016-09-15

    The estimation of emission factors (EFs) is the basis of accurate emission inventory. However, the EFs of air pollutants for motor vehicles vary under different operating conditions, which will cause uncertainty in developing emission inventory. Natural gas (NG), considered as a "cleaner" fuel than gasoline, is increasingly being used to reduce combustion emissions. However, information is scarce about how much emission reduction can be achieved by motor vehicles burning NG (NGVs) under real road driving conditions, which is necessary for evaluating the environmental benefits for NGVs. Here, online, in situ measurements of the emissions from nine bi-fuel vehicles were conducted under different operating conditions on the real road. A comparative study was performed for the EFs of black carbon (BC), carbon monoxide (CO), hydrocarbons (HCs) and nitrogen oxides (NOx) for each operating condition when the vehicles using gasoline and compressed NG (CNG) as fuel. BC EFs were reported in part I. The part II in this paper series reports the influence of operating conditions and fuel types on the EFs of CO, HC and NOx. Fuel-based EFs of CO showed good correlations with speed when burning CNG and gasoline. The correlation between fuel-based HC EFs and speed was relatively weak whether burning CNG or gasoline. The fuel-based NOx EFs moderately correlated with speed when burning CNG, but weakly correlated with gasoline. As for HC, the mileage-based EFs of gasoline vehicles are 2.39-12.59 times higher than those of CNG vehicles. The mileage-based NOx EFs of CNG vehicles are slightly higher than those of gasoline vehicles. These results would facilitate a detailed analysis of the environmental benefits for replacing gasoline with CNG in light duty vehicles. PMID:27219504

  18. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn England; Oliver Chang; Stephanie Wien

    2002-02-14

    This report provides results from the second year of this three-year project to develop dilution measurement technology for characterizing PM2.5 (particles with aerodynamic diameter smaller than 2.5 micrometers) and precursor emissions from stationary combustion sources used in oil, gas and power generation operation. Detailed emission rate and chemical speciation tests results for a gas turbine, a process heater, and a commercial oil/gas fired boiler are presented. Tests were performed using a research dilution sampling apparatus and traditional EPA methods. A series of pilot tests were conducted to identify the constraints to reduce the size of current research dilution sampler for future stack emission tests. Based on the test results, a bench prototype compact dilution sampler developed and characterized in GE EER in August 2002.

  19. Using growth and decline factors to project VOC emissions from oil and gas production.

    PubMed

    Oswald, Whitney; Harper, Kiera; Barickman, Patrick; Delaney, Colleen

    2015-01-01

    Projecting future-year emission inventories in the oil and gas sector is complicated by the fact that there is a life cycle to the amount of production from individual wells and thus from well fields in aggregate. Here we present a method to account for that fact in support of regulatory policy development. This approach also has application to air quality modeling inventories by adding a second tier of refinement to the projection methodology. Currently, modeling studies account for the future decrease in emissions due to new regulations based on the year those regulations are scheduled to take effect. The addition of a year-by-year accounting of production decline provides a more accurate picture of emissions from older, uncontrolled sources. This proof of concept approach is focused solely on oil production; however, it could be used for the activity and components of natural gas production to compile a complete inventory for a given area.

  20. Speciation Profiles and Toxic Emission Factors for Nonroad Engines: DRAFT REPORT

    EPA Science Inventory

    This document details the research and development behind how MOVES2014a estimates air toxic emissions for nonroad engines and equipment run on conventional gasoline without ethanol (E0) and gasoline blended with 10% ethanol (E10) as well as diesel fuel, compressed natural gas (C...

  1. Battery condenser system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or e...

  2. Battery condenser system PM2.5 emission factors and rates for cotton gins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is part of a series of manuscripts that detail a project to characterize cotton gin emissions from the standpoint of stack and ambient sampling. The impetus behind the project was the 2006 EPA implementation of a more stringent standard for particulate matter less than or equal to 2....

  3. Master trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than or ...

  4. Mote trash system particulate emission factors for cotton gins: Particle size distribution characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is part of a project to characterize cotton gin emissions from the standpoint of total particulate stack sampling and particle size analyses. In 2013, the U.S. Environmental Protection Agency (EPA) published a more stringent standard for particulate matter with nominal diameter less than...

  5. 40 CFR 63.1431 - Process vent annual epoxides emission factor plan requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... group determination procedures in the NESHAP for Group I Polymers and Resins (40 CFR part 63, subpart U..., recovery, or recapture device, along with the expected percent efficiency. (iii) Annual emissions after the... section, kg/yr. R = Expected control efficiency of the combustion, recovery, or recapture device,...

  6. Elemental composition of current automotive braking materials and derived air emission factors

    NASA Astrophysics Data System (ADS)

    Hulskotte, J. H. J.; Roskam, G. D.; Denier van der Gon, H. A. C.

    2014-12-01

    Wear-related PM emissions are an important constituent of total PM emissions from road transport. Due to ongoing (further) exhaust emission reduction wear emissions may become the dominant PM source from road transport in the near future. The chemical composition of the wear emissions is crucial information to assess the potential health relevance of these PM emissions. Here we provide an elemental composition profile of brake wear emissions as used in the Netherlands in 2012. In total, 65 spent brake pads and 15 brake discs were collected in car maintenance shops from in-use personal cars vehicles and analyzed with XRF for their metal composition (Fe, Cu, Zn, Sn, Al, Si, Zr, Ti, Sb, Cr, Mo, Mn, V, Ni, Bi, W, P, Pb and Co). Since car, engine and safety regulations are not nationally determined but controlled by European legislation the resulting profiles will be representative for the European personal car fleet. The brake pads contained Fe and Cu as the dominant metals but their ratio varied considerably, other relatively important metals were Sn, Zn and Sb. Overall a rather robust picture emerged with Fe, Cu, Zn and Sn together making up about 80-90% of the metals present in brake pads. Because the XRF did not give information on the contents of other material such as carbon, oxygen and sulphur, a representative selection of 9 brake pads was further analyzed by ICP-MS and a carbon and sulphur analyzer. The brake pads contained about 50% of non-metal material (26% C, 3% S and the remainder mostly oxygen and some magnesium). Based on our measurements, the average brake pad profile contained 20% Fe, 10% Cu, 4% Zn and 3% Sn as the dominant metals. The brake discs consisted almost entirely of metal with iron being the dominant metal (>95%) and only traces of other metals (<1% for individual metals). Non-metal components in the discs were 2-3% Silicon and, according to literature, ∼3% carbon. The robust ratio between Fe and Cu as found on kerbsides has been used to

  7. Estimation and validation of PM 2.5/PM 10 exhaust and non-exhaust emission factors for practical street pollution modelling

    NASA Astrophysics Data System (ADS)

    Ketzel, Matthias; Omstedt, Gunnar; Johansson, Christer; Düring, Ingo; Pohjola, Mia; Oettl, Dietmar; Gidhagen, Lars; Wåhlin, Peter; Lohmeyer, Achim; Haakana, Mervi; Berkowicz, Ruwim

    In order to carry out efficient traffic and air quality management, validated models and PM emission estimates are needed. This paper compares current available emission factor estimates for PM 10 and PM 2.5 from emission databases and different emission models, and validates these against eight high quality street pollution measurements in Denmark, Sweden, Germany, Finland and Austria. The data sets show large variation of the PM concentration and emission factors with season and with location. Consistently at all roads the PM 10 and PM 2.5 emission factors are lower in the summer month than the rest of the year. For example, PM 10 emission factors are in average 5-45% lower during the month 6-10 compared to the annual average. The range of observed total emission factors (including non-exhaust emissions) for the different sites during summer conditions are 80-130 mg km -1 for PM 10, 30-60 mg km -1 for PM 2.5 and 20-50 mg km -1 for the exhaust emissions. We present two different strategies regarding modelling of PM emissions: (1) For Nordic conditions with strong seasonal variations due to studded tyres and the use of sand/salt as anti-skid treatment a time varying emission model is needed. An empirical model accounting for these Nordic conditions was previously developed in Sweden. (2) For other roads with a less pronounced seasonal variation (e.g. in Denmark, Germany, Austria) methods using a constant emission factor maybe appropriate. Two models are presented here. Further, we apply the different emission models to data sets outside the original countries. For example, we apply the "Swedish" model for two streets without studded tyre usage and the "German" model for Nordic data sets. The "Swedish" empirical model performs best for streets with studded tyre use, but was not able to improve the correlation versus measurements in comparison to using constant emission factors for the Danish side. The "German" method performed well for the streets without clear

  8. Nitrous oxide exchanges with the atmosphere of a constructed wetland treating wastewater. Parameters and implications for emission factors

    NASA Astrophysics Data System (ADS)

    Johansson, A. E.; Kasimir Klemedtsson, Å.; Klemedtsson, L.; Svensson, B. H.

    2003-07-01

    Static chamber measurements of N2O fluxes were taken during the 1998 and 1999 growth seasons in a Swedish constructed wetland receiving wastewater. The dominating plant species in different parts of the wetland were Lemna minor L., Typha latifolia L., Spirogyra sp. and Glyceria maxima (Hartm.) and Phalaris arundinacea (L.), respectively. There were large temporal and spatial variations in N2O fluxes, which ranged from consumption at -350 to emissions at 1791 μg N2O m-2 h-1. The largest positive flux occurred in October 1999 and the lowest in the middle of July 1999. The average N2O flux for the two years was 130 μg N2O m-2 h-1 (SD = 220). No significant differences in N2O fluxes were found between the years, even though the two growing seasons differed considerably with respect to both air temperature and precipitation. 15% of the fluxes were negative, showing a consumption of N2O. Consumption occurred on a few occasions at most measurement sites and ranged from 1-350 μg N2O m-2 h-1. 13-43% of the variation in N2O fluxes was explained by multiple linear regression analysis including principal components. Emission factors were calculated according to IPCC methods from the N2O fluxes in the constructed wetland. The calculated emission factors were always lower (0.02-0.27%) compared to the default factor provided by the IPCC (0.75%). Thus, direct application of the IPCC default factor may lead to overestimation of N2O fluxes from constructed wastewater-treating wetlands.

  9. Compilation of air-pollutant emission factors. Volume 1. Stationary-point and area sources, Fourth Edition. Supplement A

    SciTech Connect

    Joyner, W.M.

    1986-10-01

    In the supplement to the Fourth Edition of AP-42, new or revised emissions data are presented for Bituminous and subbituminous coal combustion; Anthracite coal combustion; Fuel oil combustion; Natural gas combustion; Wood waste combustion in boilers; Lignite combustion; Sodium carbonate; Primary aluminum production; Coke production; Primary copper smelting; Ferroalloy production; Iron and steel production; Primary lead smelting; Zinc smelting; Secondary aluminum operations; Gray iron foundries; Secondary lead smelting; Asphaltic concrete plants; Bricks and related clay products; Portland cement manufacturing; Concrete batching; Glass manufacturing; Lime manufacturing; Construction aggregate processing; Taconite ore processing; Western surface coal mining; Chemical wood pulping; Appendix C.1, Particle-size distribution data and sized emission factors for selected sources; and Appendix C.2, Generalized particle size distributions.

  10. Particulate matter and black carbon optical properties and emission factors from prescribed fires in the southeastern United States

    NASA Astrophysics Data System (ADS)

    Holder, Amara L.; Hagler, Gayle S. W.; Aurell, Johanna; Hays, Michael D.; Gullett, Brian K.

    2016-04-01

    Aerosol optical properties of biomass burning emissions are critical parameters determining how these emissions impact the Earth's climate. Despite their importance, field measurements of aerosol optical properties from fires remain scarce. Aerosol emissions from prescribed fires of forested and grass plots in the southeastern United States were measured and compared to emissions from laboratory simulations. Fine particulate matter (PM2.5), black carbon (BC), and aerosol light scattering and absorption were characterized for all fires. Refractory BC emission factors (EFs) measured at ground level (~2 m) were 0.76 ± 0.15 g/kg, comparable to the 0.93 ± 0.32 g/kg measured aloft (~100-600 m). However, PM EFs measured by aircraft were only 18% (5.4 ± 2.0 g/kg) of those measured on the ground (28.8 ± 9.8 g/kg). Such large differences in PM EFs for the same fire have not been previously reported and may plausibly be due to the differing particle measurement methodologies being applied but also likely related to partitioning of organic compounds to the gas phase as the plume dilutes aloft. Higher PM EFs on the ground may also be related to a higher contribution from smoldering combustion. The absorption Ångström exponents (αa) for the high intensity South Carolina fires were 3.92 ± 0.6, which was larger than prescribed forest fire in Florida (2.84) and the grass fire in Florida (2.71), implying a larger absorption contribution from brown carbon from higher-intensity fires. Aerosol optical properties from laboratory simulations did not represent field measurements.

  11. Emission factors of particulate matter and elemental carbon for crop residues and coals burned in typical household stoves in China

    PubMed Central

    Shen, Guofeng; Yang, Yifeng; Wang, Wei; Tao, Shu; Zhu, Chen; Min, Yujia; Xue, Miao; Ding, Junnan; Wang, Bin; Wang, Rong; Shen, Huizhong; Li, Wei; Wang, Xilong; Russell, Armistead G.

    2013-01-01

    Both particulate matter (PM) and black carbon (BC) impact climate change and human health. Uncertainties in emission inventories of PM and BC are partially due to large variation of measured emission factors (EFs) and lack of EFs from developing countries. Although there is a debate whether thermal-optically measured elemental carbon (EC) may be referred to as BC, EC are often treated as the same mass of BC. In this study, EFs of PM (EFPM) and EC (EFEC) for 9 crop residues and 5 coals were measured in actual rural cooking and coal stoves using the carbon mass balance method. The dependence of the EFs on fuel properties and combustion conditions were investigated. It was found that the mean EFPM were 8.19 ± 4.27 and 3.17 ± 4.67 g/kg and the mean EFEC were 1.38 ± 0.70 and 0.23 ± 0.36 g/kg for crop residues and coals, respectively. PM with size less than 10 μm (PM10) from crop residues were dominated by particles of aerodynamic size ranging from 0.7 to 2.1 μm, while the most abundant size ranges of PM10 from coals were either from 0.7 to 2.1 μm or less than 0.7 μm. Of various fuel properties and combustion conditions tested, fuel moisture and modified combustion efficiency (MCE) were the most critical factors affecting EFPM and EFEC for crop residues. For coal combustion, EFPM were primarily affected by MCE and volatile matter, while EFEC were significantly influenced by ash content, volatile matter, heat value, and MCE. It was also found that EC emissions were significantly correlated with emissions of PM with size less than 0.4 μm. PMID:20735038

  12. Emission factors of particulate matter and elemental carbon for crop residues and coals burned in typical household stoves in China.

    PubMed

    Shen, Guofeng; Yang, Yifeng; Wang, Wei; Tao, Shu; Zhu, Chen; Min, Yujia; Xue, Miao; Ding, Junnan; Wang, Bin; Wang, Rong; Shen, Huizhong; Li, Wei; Wang, Xilong; Russell, Armistead G

    2010-09-15

    Both particulate matter (PM) and black carbon (BC) impact climate change and human health. Uncertainties in emission inventories of PM and BC are partially due to large variation of measured emission factors (EFs) and lack of EFs from developing countries. Although there is a debate whether thermal-optically measured elemental carbon (EC) may be referred to as BC, EC is often treated as the same mass of BC. In this study, EFs of PM (EF(PM)) and EC (EF(EC)) for 9 crop residues and 5 coals were measured in actual rural cooking and coal stoves using the carbon mass balance method. The dependence of the EFs on fuel properties and combustion conditions was investigated. It was found that the mean EF(PM) were 8.19 ± 4.27 and 3.17 ± 4.67 g/kg and the mean EF(EC) were 1.38 ± 0.70 and 0.23 ± 0.36 g/kg for crop residues and coals, respectively. PM with size less than 10 μm (PM(10)) from crop residues were dominated by particles of aerodynamic size ranging from 0.7 to 2.1 μm, while the most abundant size ranges of PM(10) from coals were either from 0.7 to 2.1 μm or less than 0.7 μm. Of various fuel properties and combustion conditions tested, fuel moisture and modified combustion efficiency (MCE) were the most critical factors affecting EF(PM) and EF(EC) for crop residues. For coal combustion, EF(PM) were primarily affected by MCE and volatile matter, whereas EF(EC) were significantly influenced by ash content, volatile matter, heat value, and MCE. It was also found that EC emissions were significantly correlated with emissions of PM with size less than 0.4 μm. PMID:20735038

  13. Emission factors for gases and particle-bound substances produced by firing lead-free small-caliber ammunition.

    PubMed

    Wingfors, H; Svensson, K; Hägglund, L; Hedenstierna, S; Magnusson, R

    2014-01-01

    Lead-free ammunition is becoming increasingly popular because of the environmental and human health issues associated with the use of leaded ammunition. However, there is a lack of data on the emissions produced by firing such ammunition. We report emission factors for toxic gases and particle-bound compounds produced by firing lead-free ammunition in a test chamber. Carbon monoxide, ammonia, and hydrogen cyanide levels within the chamber were analysed by Fourier transform infrared spectroscopy, while total suspended particles and respirable particles were determined gravimetrically. The metal content of the particulate emissions was determined and the associated organic compounds were characterized in detail using a method based on thermal desorption coupled to gas chromatography and mass spectrometry. The particulate matter (∼30 mg/round) consisted primarily of metals such as Cu, Zn, and Fe along with soot arising from incomplete combustion. Nitrogen-containing heterocyclic aromatic compounds such as carbazole, quinolone, and phenazine were responsible for some of the 25 most significant chromatographic peaks, together with PAHs, diphenylamine, and phthalates. Emission factors were determined for PAHs and oxygenated PAHs; the latter were less abundant in the gun smoke particles than in domestic dust and diesel combustion smoke. This may be due to the oxygen-deficient conditions that occur when the gun is fired. By using an electrical low pressure impactor, it was demonstrated that more than 90% of the particles produced immediately after firing the weapon had diameters of less than 30 nm, and so most of the gun smoke particles belonged to the nanoparticle regime.

  14. Factors Influencing Microbial Carbon Emission Potential from Wetland Sediments and its Relation to Surface- and Plot-Scale Measurements

    NASA Astrophysics Data System (ADS)

    Brooker, M.; Bohrer, G.; Mouser, P. J.

    2012-12-01

    Wetlands provide valuable ecosystem services by sequestering carbon dioxide from the atmosphere and serving as a sink for atmospheric nitrogen export. They are often constructed as buffers between agriculture lands and drainage channels to improve runoff water quality from elevated nutrient loading (e.g. nitrate-N). Unfortunately, carbon sequestration and denitrification in wetlands come with the tradeoff of increased production of methane, another more potent green house gas. Existing models correlate methane emission rates to increased temperature; however, surface- and plot-scale measurements show little or weak relationships between these factors at the field scale. This study examines the relationship of several environmental factors - temperature, zone location, and microbial community - to methane emissions under controlled laboratory conditions. Water and sediments collected from two depths (0-6" and 6-12") and four distinct biomes (open water and three distinct emergent macrophyte covers) were used to prepare anaerobic microcosms at two different temperatures (20°C and 30°C). Headspace gas (methane, carbon dioxide), water chemistry, and microbial community composition were analyzed over the course of several months. We observed: 1) an increase in methane emission potential with higher temperature; 2) higher levels of methane produced from shallower sediments; 3) differential production of methane versus carbon dioxide depending upon biome; and 4) variations in bacterial and archaeal diversity relating to methane production rates. This data helps provide upper limit estimates for methane emissions from wetlands by methanogenic Archaea and informs our ability to better parameterize biogeochemical and atmospheric models of these systems.

  15. Should particle size analysis data be combined with EPA approved sampling method data in the development of AP-42 emission factors?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A cotton ginning industry-supported project was initiated in 2008 and completed in 2013 to collect additional data for U.S. Environmental Protection Agency’s (EPA) Compilation of Air Pollution Emission Factors (AP-42) for PM10 and PM2.5. Stack emissions were collected using particle size distributio...

  16. Size-specific-particulate emission factors for industrial and rural roads: source category report. Final task report, June 1981-June 1985

    SciTech Connect

    Cowherd, C.; Englehart, P.J.

    1985-10-01

    The report gives results of a study to derive size-specific particulate emission factors for industrial paved and unpaved roads and for rural unpaved roads from an existing field testing data base. Regression analysis was used to develop predictive emission factor equations which relate emission quantities to road and traffic parameters. Separate equations were developed for each road type and for three aerodynamic particle size fractions: < or = 15, < or = 10, and < or = 2.5 micrometers. Recommendations are made for including the resulting emission factors in EPA document AP-42. Over the past few years, traffic-generated dust emissions from unpaved and paved industrial roads have become recognized as a significant source of atmospheric particulate emissions, especially within industries involved in mining and processing mineral aggregates. Although a considerable amount of field testing of industrial roads has been performed, most studies have focused on total suspended particulate (TSP) emissions, because the current national ambient air quality standards (NAAQS) for particulate matter are based on TSP. Only recently, in anticipation of a NAAQS for particulate matter based on particle size, has the emphasis shifted to the development of size-specific emission factors.

  17. Influence factors and mechanism of emission of ZnS:Cu nanocrystals

    NASA Astrophysics Data System (ADS)

    Chu, Xue-Ying; Wang, Xin-Nong; Li, Jin-Hua; Yao, Dan; Fang, Xuan; Fang, Fang; Wei, Zhi-Peng; Wang, Xiao-Hua

    2015-06-01

    Copper-doped ZnS (ZnS:Cu) nanocrystals are synthesized by the sol-gel method. The average size of the ZnS:Cu nanocrystals is 3.1 nm. The x-ray diffraction indicates that increasing the Cu-dopant concentration results in a large shift in the diffraction angle. The effects of the dopant concentration, the reactant ratio, and aging temperature on the optical properties of the ZnS:Cu nanocrystals are also investigated. The fluorescence emission mechanism is analyzed by peak deconvolution using Gaussian functions. We find that the emission of the ZnS:Cu nanocrystal is composed of different luminescence centers at 430, 470, 490, 526, and 560 nm. The origins of these emissions are discussed and demonstrated by controlled experiments. Project supported by the National Natural Science Foundation of China (Grant Nos. 61205193, 61204065, and 61307045), the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20112216120005), and the Developing Project of Science and Technology of Jilin Province, China (Grant Nos. 201201116, 20140520107JH, and 20140204025GX).

  18. Emission Characteristics and Factors of Selected Odorous Compounds at a Wastewater Treatment Plant

    PubMed Central

    Jeon, Eui-Chan; Son, Hyun-Keun; Sa, Jae-Hwan

    2009-01-01

    This study was initiated to explore the emission characteristics of Reduced Sulfur Compounds (RSCs: hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide), ammonia and trimethylamine from a Wastewater Treatment Plant (WWTP) located at Sun-Cheon, Chonlanam-Do in South Korea. The study also evaluates flux profiles of the six selected odorous compounds and their flux rates (μg/m2/min) and compares their emission characteristics. A Dynamic Flux Chamber DFC was used to measure fluxes of pollutants from the treatment plant. Quality control of odor samples using a non-reactive sulfur dioxide gas determined the time taken for DFC concentration to reach equilibrium. The reduced sulfur compounds were analyzed by interfacing gas chromatography with a Pulsed Flame Photometric Detector (PFPD). Air samples were collected in the morning and afternoon on one day during summer (August) and two days in winter (December and January). Their emission rates were determined and it was observed that during summer relatively higher amounts of the selected odorous compounds were emitted compared to winter. Air samples from primary settling basin, aeration basin, and final settling basin were tested and the total amount of selected odorous compounds emitted per wastewater ton was found to be 1344 μg/m3 from the selected treatment processes. It was also observed that, in this study, the dominant odor intensity contribution was caused by dimethyl disulfide (69.1%). PMID:22389601

  19. Soil Pore Characteristics, an Underappreciated Regulatory Factor in GHGs Emission and C Stabilization

    NASA Astrophysics Data System (ADS)

    Toosi, E. R.; Yu, J.; Doane, T. A.; Guber, A.; Rivers, M. L.; Marsh, T. L.; Ali, K.; Kravchenko, A. N.

    2015-12-01

    Enduring challenges in understanding soil organic matter (SOM) stability and emission of greenhouse gases (GHGs) from soil stem from complexities of soil processes, many of which occur at micro-scales. The goal of this study is to evaluate the interactive effects soil pore characteristics, soil moisture levels, inherent SOM levels and properties, and substrate quality, on GHGs emission, and accelerated decomposition of native SOM following addition of fresh substrate i.e. priming. Our core hypothesis is that soil pore characteristics play a major role as a mediator in (i) the decomposition of organic matter regardless of its source (i.e. litter vs. native SOM) or substrate quality, as well as in (ii) GHGs emissions. Samples with prevalence of small (<10 μm) vs. large (>30 μm) pores were prepared from soils with similar properties but under long-term contrasting management. The samples were incubated (110 d) at low and optimum soil moisture conditions after addition of high quality (13C-soybean) and low quality (13C-corn) substrate. Headspace gas was analyzed for 13C-CO2 and GHGs on a regularly basis (day 1, 3, 7, 14, 24, 36, 48, 60, 72, 90, and 110). Selected samples were scanned at the early stage of decomposition (7, 14, 24 d) at 2-6 μm resolutions using X-ray computed μ tomography in order to: (1) quantify soil pore characteristics; (2) visualize and quantify distribution of soil moisture within samples of different pore characteristics; and (3) to visualize and measure losses of decomposing plant residue. Initial findings indicate that, consistent with our hypotheses, pore characteristics influenced GHGs emission, and intensity and pattern of plant residue decomposition. The importance of pores was highly pronounced in presence of added plant residue where greater N2O emission occurred in samples with dominant large pores, in contrast to CO2. Further findings will be discussed upon completion of the study and analysis of the results.

  20. Controlling factors of nitrous oxide (N2O) emissions at the field-scale in an agricultural slope

    NASA Astrophysics Data System (ADS)

    Vilain, Guillaume; Garnier, Josette; Tallec, Gaëlle; Tournebize, Julien; Cellier, Pierre; Flipo, Nicolas

    2010-05-01

    Agricultural practices widely contribute to the atmospheric nitrous oxide (N2O) concentration increase and are the major source of N2O which account for 24% of the global annual emission (IPCC, 2007). Soil nitrification and denitrification are the microbial processes responsible for the production of N2O, which also depends on soil characteristics and management. Besides their control by various factors, such as climate, soil conditions and management (content of NO3- and NH4+, soil water content, presence of degradable organic material…), the role of topography is less known although it can play an important role on N2O emissions (Izaurralde et al., 2004). Due to the scarcity of data on N2O direct vs. indirect emission rate from agriculture in the Seine Basin (Garnier et al., 2009), one of the objectives of the study conducted here was to determine the N2O emission rates of the various land use representative for the Seine Basin, in order to better assess the direct N2O emissions, and to explore controlling factor such as meteorology, topography, soil properties and crop successions. The main objective of this study was at the same time to characterize N2O fluxes variability along a transect from an agricultural plateau to a river and to analyze the influence of landscape position on these emissions. We conducted this study in the Orgeval catchment (Seine basin, France; between 48°47' and 48°55' N, and 03°00' and 03°55' E) from May 2008 to August 2009 on two agricultural fields cropped with wheat, barley, oats, corn. N2O fluxes were monitored from weekly to bimonthly using static manual chambers placed along the chosen transect in five different landscape positions from the plateau to the River. This study has shown that soil moisture (expressed as Water Filled Pore Space) and NO3- soil concentrations explained most of the N2O flux variability during the sampling period. Most of N2O was emitted directly after N fertilization application during a relatively

  1. Atmospheric pollutant emission factors from open burning of agricultural and forest biomass by wind tunnel simulations. Volume 2. Results, cereal crop residues. Final report

    SciTech Connect

    Jenkins, B.M.; Turn, S.Q.; Williams, R.B.; Goronea, M.; Abd-el-Fattah, H.

    1996-04-01

    Atmospheric pollutant emission factors were determined by wind tunnel simulations of spreading and pile fires for 8 different types of fuel including barley, rice and wheat straw, corn stove, almond and walnut tree prunings, and Douglas fir and Ponderosa pine slash. Emission factors were determined for each fuel for CO, NO, NOx, SO2, total hydrocarbons, methane, non-methane hydrocarbons, total sulfur, CO2, particulate matter, volatile organic matter (VOC), and polycyclic aromatic hydrocarbons (PAH). Elemental compositions of particulate matter were determined by size category. Bulk aerosol absorption coefficients were determined from light transmission measurements through filter samples. Emission rates were correlated against burning conditions and fuel compositions. Factors affecting the burning rates and emission factors included inlet air temperature, loading rate, and wind speed. Vol. 2 contains data from cereal straws and stovers.

  2. Atmospheric pollutant emission factors from open burning of agricultural and forest biomass by wind tunnel simulations. Volume 3. Results, wood fuels. Final report

    SciTech Connect

    Jenkins, B.M.; Turn, S.Q.; Williams, R.B.; Goronea, M.; Abd-el-Fattah, H.

    1996-04-01

    Atmospheric pollutant emission factors were determined by wind tunnel simulations of spreading and pile fires for 8 different types of fuel including barley, rice and wheat straw, corn stover, almond and walnut tree prunings, and Douglas fir and Ponderosa pine slash. Emission factors were determined for each fuel for CO, NO, NOx, SO2, total hydrocarbons, methane, non-methane hydrocarbons, total sulfur, CO2, particulate matter, volatile organic matter (VOC), and polycyclic aromatic hydrocarbons determined from light transmission measurements through filter samples. Emission rate were correlated against burning conditions and fuel compositions. Factors affecting the buring rates and emission factors included inlet air temperature, loading rate, and wind speed. Volume 3 contains data from wood fuels.

  3. Escape factors for Paschen 2p–1s emission lines in low-temperature Ar, Kr, and Xe plasmas

    NASA Astrophysics Data System (ADS)

    Zhu, Xi-Ming; Cheng, Zhi-Wen; Pu, Yi-Kang; Czarnetzki, Uwe

    2016-06-01

    Radiation trapping phenomenon is often observed when investigating low-temperature plasmas. Photons emitted from the upper excited states may be reabsorbed by the lower states before they leave the plasmas. In order to account for this effect in the modelling and optical diagnostics of plasmas, either an ‘escape factor’ of a function of the optical depth or a strict solution of the radiation transfer equation can be employed. However, the former is more convenient in comparison and thus is widely adopted. Previous literatures have provided several simple expressions of the escape factor for the uniform plasmas. The emission line profiles are assumed to be dominated by the Doppler broadening, and the line splitting due to the hyperfine structure is not considered. This kind of expression is only valid for small atoms, e.g. Ar in low-pressure uniform discharges. Actually, the excited state density in many of the low-temperature plasmas is non-uniform and the emission line profile can be significantly influenced by the collisional broadening at medium and high pressures. In these cases, a new escape factor equation should be calculated. In this work, we study the escape factor equations for the often used 2p–1s transitions (Paschen’s notation) of the Ar, Kr, and Xe atoms. Possible non-uniform density profiles are considered. In addition, we include the line splitting due to the hyperfine structure for Kr and Xe. For the low-pressure plasmas, an escape factor expression mainly based on the Gaussian line profile is given and particularly verified by an experiment in a low-pressure capacitive discharge. For the high-pressure plasmas, an equation based on the Voigt line profile is also calculated. In this way, the new escape factor expression is ready for use in the modelling of the Ar, Kr, and Xe plasmas from low to atmospheric pressure.

  4. Escape factors for Paschen 2p-1s emission lines in low-temperature Ar, Kr, and Xe plasmas

    NASA Astrophysics Data System (ADS)

    Zhu, Xi-Ming; Cheng, Zhi-Wen; Pu, Yi-Kang; Czarnetzki, Uwe

    2016-06-01

    Radiation trapping phenomenon is often observed when investigating low-temperature plasmas. Photons emitted from the upper excited states may be reabsorbed by the lower states before they leave the plasmas. In order to account for this effect in the modelling and optical diagnostics of plasmas, either an ‘escape factor’ of a function of the optical depth or a strict solution of the radiation transfer equation can be employed. However, the former is more convenient in comparison and thus is widely adopted. Previous literatures have provided several simple expressions of the escape factor for the uniform plasmas. The emission line profiles are assumed to be dominated by the Doppler broadening, and the line splitting due to the hyperfine structure is not considered. This kind of expression is only valid for small atoms, e.g. Ar in low-pressure uniform discharges. Actually, the excited state density in many of the low-temperature plasmas is non-uniform and the emission line profile can be significantly influenced by the collisional broadening at medium and high pressures. In these cases, a new escape factor equation should be calculated. In this work, we study the escape factor equations for the often used 2p-1s transitions (Paschen’s notation) of the Ar, Kr, and Xe atoms. Possible non-uniform density profiles are considered. In addition, we include the line splitting due to the hyperfine structure for Kr and Xe. For the low-pressure plasmas, an escape factor expression mainly based on the Gaussian line profile is given and particularly verified by an experiment in a low-pressure capacitive discharge. For the high-pressure plasmas, an equation based on the Voigt line profile is also calculated. In this way, the new escape factor expression is ready for use in the modelling of the Ar, Kr, and Xe plasmas from low to atmospheric pressure.

  5. 40 CFR Table Aa-2 to Subpart Aa of... - Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O AA Table AA-2 to Subpart AA of Part 98 Protection of Environment... and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O Fuel Fossil fuel-based...

  6. 40 CFR Table Aa-2 to Subpart Aa of... - Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O AA Table AA-2 to Subpart AA of Part 98 Protection of Environment... and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O Fuel Fossil fuel-based...

  7. 40 CFR Table Aa-2 to Subpart Aa of... - Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Kraft Lime Kiln and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O AA Table AA-2 to Subpart AA of Part 98 Protection of Environment... and Calciner Emissions Factors for Fossil Fuel-Based CH4 and N2O Fuel Fossil fuel-based...

  8. Transportation Energy Futures Series: Effects of the Built Environment on Transportation: Energy Use, Greenhouse Gas Emissions, and Other Factors

    SciTech Connect

    Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.

    2013-03-01

    Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  9. Transportation Energy Futures Series. Effects of the Built Environment on Transportation. Energy Use, Greenhouse Gas Emissions, and Other Factors

    SciTech Connect

    Porter, C. D.; Brown, A.; Dunphy, R. T.; Vimmerstedt, L.

    2013-03-15

    Planning initiatives in many regions and communities aim to reduce transportation energy use, decrease emissions, and achieve related environmental benefits by changing land use. This report reviews and summarizes findings from existing literature on the relationship between the built environment and transportation energy use and greenhouse gas emissions, identifying results trends as well as potential future actions. The indirect influence of federal transportation and housing policies, as well as the direct impact of municipal regulation on land use are examined for their effect on transportation patterns and energy use. Special attention is given to the 'four D' factors of density, diversity, design and accessibility. The report concludes that policy-driven changes to the built environment could reduce transportation energy and GHG emissions from less than 1% to as much as 10% by 2050, the equivalent of 16%-18% of present-day urban light-duty-vehicle travel. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  10. Measurements of emission factors for primary carbonaceous particles from residential raw-coal combustion in China - article no. L20815

    SciTech Connect

    Chen, Y.J.; Zhi, G.R.; Feng, Y.L.; Fu, J.M.; Feng, J.L.; Sheng, G.Y.; Simoneit, B.R.T.

    2006-10-28

    The emission factors (EFs) of particles and their carbonaceous fractions, including black carbon (BC) and organic carbon (OC), are measured for residential burning of coal-chunks. Nine types of coals with wide-ranged thermal maturities were used. Particulate emissions from coal-stove are collected on quartz fiber filters through a dilution sampling system and analyzed for BC and OC by thermal-optical method. The EFs of particulate matter, OC, and BC from bituminous coal burning are 16.77, 8.29, and 3.32 g/kg, respectively, on the basis of burned dry and ash-free (daf) coal mass. They were much higher than those of anthracites, which are 0.78, 0.04, and 0.004 g/kg, respectively. Annual emission inventories of particles, OC, and BC from household coal burning are also estimated based on the EFs and coal consumption. The results of the calculations are 917.8, 477.7, and 128.4 gigagrams (Gg) for total particles, OC, and BC emitted in China during the year 2000.

  11. Compilation of air pollutant emission factors. Volume 1. Stationary point and area sources. Supplement E

    SciTech Connect

    Not Available

    1992-10-01

    In the Supplement to the Fourth Edition of AP-42 Volume I, new or revised emissions data are presented for Anthracite Coal Combustion; Natural Gas Combustion; Liquified Petroleum Gas Combustion; Wood Waste Combustion In Boilers; Bagasse Combustion In Sugar Mills; Residential Fireplaces; Residential Wood Stoves; Waste Oil Combustion; Automobile Body Incineration; Conical Burners; Open Burning; Stationary Gas Turbines for Electricity Generation; Heavy Duty Natural Gas Fired Pipeline Compressor Engines; Gasoline and Diesel Industrial Engines; Large Stationary Diesel and All Stationary Dual Fuel Engines; Soap and Detergents; and Storage of Organic Liquids.

  12. Combustion efficiency and emission factors for wildfire-season fires in mixed conifer forests of the northern Rocky Mountains, US

    NASA Astrophysics Data System (ADS)

    Urbanski, S. P.

    2013-07-01

    In the US, wildfires and prescribed burning present significant challenges to air regulatory agencies attempting to achieve and maintain compliance with air quality regulations. Fire emission factors (EF) are essential input for the emission models used to develop wildland fire emission inventories. Most previous studies quantifying wildland fire EF of temperate ecosystems have focused on emissions from prescribed burning conducted outside of the wildfire season. Little information is available on EF for wildfires in temperate forests of the conterminous US. The goal of this work is to provide information on emissions from wildfire-season forest fires in the northern Rocky Mountains, US. In August 2011, we deployed airborne chemistry instruments and sampled emissions over eight days from three wildfires and a prescribed fire that occurred in mixed conifer forests of the northern Rocky Mountains. We measured the combustion efficiency, quantified as the modified combustion efficiency (MCE), and EF for CO2, CO, and CH4. Our study average values for MCE, EFCO2, EFCO, and EFCH4 were 0.883, 1596 g kg-1, 135 g kg-1, 7.30 g kg-1, respectively. Compared with previous field studies of prescribed fires in temperate forests, the fires sampled in our study had significantly lower MCE and EFCO2 and significantly higher EFCO and EFCH4. The fires sampled in this study burned in areas reported to have moderate to heavy components of standing dead trees and down dead wood due to insect activity and previous fire, but fuel consumption data was not available. However, an analysis of MCE and fuel consumption data from 18 prescribed fires reported in the literature indicates that the availability of coarse fuels and conditions favorable for the combustion of these fuels favors low MCE fires. This analysis suggests that fuel composition was an important factor contributing to the low MCE of the fires measured in this study. This study only measured EF for CO2, CO, and CH4; however, we

  13. Factors controlling peat chemistry and vegetation composition in Sudbury peatlands after 30 years of pollution emission reductions.

    PubMed

    Barrett, Sophie E; Watmough, Shaun A

    2015-11-01

    The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands surrounding Sudbury after more than 30 years of large (>95%) pollution emission reductions. Sites closer to the main Copper Cliff smelter had more humified peat and the surface horizons were greatly enriched in copper (Cu) and nickel (Ni). Copper and Ni concentrations in peat were significantly correlated with that in the plant tissue of Chamaedaphne calyculata. The pH of peat was the strongest determining factor for species richness, diversity, and community composition, although percent vascular plant cover was strongly negatively correlated with surface Cu and Ni concentrations in peat. Sphagnum frequency was also negatively related to peat Cu and Ni concentrations indicating sites close to Copper Cliff smelter remain adversely impacted by industrial activities.

  14. Factors controlling peat chemistry and vegetation composition in Sudbury peatlands after 30 years of pollution emission reductions.

    PubMed

    Barrett, Sophie E; Watmough, Shaun A

    2015-11-01

    The objective of this research was to assess factors controlling peat and plant chemistry, and vegetation composition in 18 peatlands surrounding Sudbury after more than 30 years of large (>95%) pollution emission reductions. Sites closer to the main Copper Cliff smelter had more humified peat and the surface horizons were greatly enriched in copper (Cu) and nickel (Ni). Copper and Ni concentrations in peat were significantly correlated with that in the plant tissue of Chamaedaphne calyculata. The pH of peat was the strongest determining factor for species richness, diversity, and community composition, although percent vascular plant cover was strongly negatively correlated with surface Cu and Ni concentrations in peat. Sphagnum frequency was also negatively related to peat Cu and Ni concentrations indicating sites close to Copper Cliff smelter remain adversely impacted by industrial activities. PMID:26160672

  15. Brown carbon aerosols from burning of boreal peatlands: microphysical properties, emission factors, and implications for direct radiative forcing

    NASA Astrophysics Data System (ADS)

    Chakrabarty, Rajan K.; Gyawali, Madhu; Yatavelli, Reddy L. N.; Pandey, Apoorva; Watts, Adam C.; Knue, Joseph; Chen, Lung-Wen A.; Pattison, Robert R.; Tsibart, Anna; Samburova, Vera; Moosmüller, Hans

    2016-03-01

    The surface air warming over the Arctic has been almost twice as much as the global average in recent decades. In this region, unprecedented amounts of smoldering peat fires have been identified as a major emission source of climate-warming agents. While much is known about greenhouse gas emissions from these fires, there is a knowledge gap on the nature of particulate emissions and their potential role in atmospheric warming. Here, we show that aerosols emitted from burning of Alaskan and Siberian peatlands are predominantly brown carbon (BrC) - a class of visible light-absorbing organic carbon (OC) - with a negligible amount of black carbon content. The mean fuel-based emission factors for OC aerosols ranged from 3.8 to 16.6 g kg-1. Their mass absorption efficiencies were in the range of 0.2-0.8 m2 g-1 at 405 nm (violet) and dropped sharply to 0.03-0.07 m2 g-1 at 532 nm (green), characterized by a mean Ångström exponent of ≈ 9. Electron microscopy images of the particles revealed their morphologies to be either single sphere or agglomerated "tar balls". The shortwave top-of-atmosphere aerosol radiative forcing per unit optical depth under clear-sky conditions was estimated as a function of surface albedo. Only over bright surfaces with albedo greater than 0.6, such as snow cover and low-level clouds, the emitted aerosols could result in a net warming (positive forcing) of the atmosphere.

  16. Real-time black carbon emission factors of light-duty vehicles tested on a chassis dynamometer

    NASA Astrophysics Data System (ADS)

    Forestieri, S. D.; Cappa, C. D.; Kuwayama, T.; Collier, S.; Zhang, Q.; Kleeman, M. J.

    2012-12-01

    Eight light-duty gasoline vehicles were tested on a Chassis dynamometer using the California Unified Driving Cycle (UDC) at the Haagen-Smit vehicle test facility at the California Air Resources Board (CARB) in El Monte, CA during September 2011. In addition, one light-duty gasoline vehicle, one ultra low-emission vehicle, one diesel passenger vehicle, and one gasoline direct injection vehicle were tested on a constant velocity driving cycle. Vehicle exhaust was diluted through CARB's CVS tunnel and a secondary dilution system in order to examine particulate matter (PM) emissions at atmospherically relevant concentrations (5-30 μg-m3). A variety of real-time instrumentation was used to characterize how the major PM components vary during a typical driving cycle, which includes a cold start phase followed by a hot stabilized running phase. Aerosol absorption coefficients were obtained at 532 nm and 405 nm with a time resolution of 2 seconds from a photo-acoustic spectrometer. These absorption coefficients were then converted to black carbon (BC) concentrations via a mass absorption coefficient. Non-refractory organic and inorganic PM and CO2 concentrations were quantified with a time resolution of 10 seconds using a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS). Real-time BC and CO2 concentrations allowed for the determination of BC emission factors (EFs), providing insights into the variability of BC EFs during different phases of a typical driving cycle and aiding in the modeling BC emissions.

  17. DEVELOPMENT OF FINE PARTICULATE EMISSION FACTORS AND SPECIATION PROFILES FOR OIL AND GAS-FIRED COMBUSTION SYSTEMS

    SciTech Connect

    Glenn C. England

    2004-10-20

    ambient air to dilute the stack gas sample followed by 80-90 seconds residence time to allow aerosol formation and growth to stabilize prior to sample collection and analysis. More accurate and complete emissions data generated using the methods developed in this program will enable more accurate source-receptor and source apportionment analysis for PM2.5 National Ambient Air Quality Standards (NAAQS) implementation and streamline the environmental assessment of oil, gas and power production facilities. The overall goals of this program were to: (1) Develop improved dilution sampling technology and test methods for PM2.5 mass emissions and speciation measurements, and compare results obtained with dilution and traditional stationary source sampling methods. (2) Develop emission factors and speciation profiles for emissions of fine particulate matter, especially organic aerosols, for use in source-receptor and source apportionment analyses. (3) Identify and characterize PM2.5 precursor compound emissions that can be used in source-receptor and source apportionment analyses.

  18. Spatial variability of nitrous oxide emissions and their soil-related determining factors in an agricultural field.

    PubMed

    Yanai, Junta; Sawamoto, Takuji; Oe, Taku; Kusa, Kanako; Yamakawa, Keisuke; Sakamoto, Kazunori; Naganawa, Takahiko; Inubushi, Kazuyuki; Hatano, Ryusuke; Kosaki, Takashi

    2003-01-01

    To evaluate spatial variability of nitrous oxide (N2O) emissions and to elucidate their determining factors on a field-scale basis, N2O fluxes and various soil properties were evaluated in a 100- x 100-m onion (Allium cepa L.) field. Nitrous oxide fluxes were determined by a closed chamber method from the one-hundred 10- x 10-m plots. Physical (e.g., bulk density and water content), chemical (e.g., total N and pH), and biological (e.g., microbial biomass C and N) properties were determined from surface soil samples (0-0.1 m) of each plot. Geostatistical analysis was performed to examine spatial variability of both N2O fluxes and soil properties. Multivariate analysis was also conducted to elucidate relationships between soil properties and observed fluxes. Nitrous oxide fluxes were highly variable (average 331 microg N m(-2) h(-1), CV 217%) and were log-normally distributed. Log-transformed N2O fluxes had moderate spatial dependence with a range of >75 m. High N2O fluxes were observed at sites with relatively low elevation. Multivariate analysis indicated that an organic matter factor and a pH factor of the principal component analysis were the main soil-related determining factors of log-transformed N2O fluxes. By combining multivariate analysis with geostatistics, a map of predicted N2O fluxes closely matched the spatial pattern of measured fluxes. The regression equation based on the soil properties explained 56% of the spatially structured variation of the log-transformed N2O fluxes. Site-specific management to regulate organic matter content and water status of a soil could be a promising means of reducing N2O emissions from agricultural fields. PMID:14674518

  19. Evaluating the air quality impacts of the 2008 Beijing Olympic Games: On-road emission factors and black carbon profiles

    NASA Astrophysics Data System (ADS)

    Wang, Xing; Westerdahl, Dane; Chen, Lung Chi; Wu, Ye; Hao, Jiming; Pan, Xiaochuan; Guo, Xinbiao; Zhang, K. Max

    The aggressive traffic interventions and emission control measures implemented to improve air quality during the 2008 Beijing Olympic Games created a valuable case study to evaluate the effectiveness of these measures on mitigating air pollution and protecting public health. In this paper, we report the results from our field campaign in summer 2008 on the on-road emission factors of carbon monoxide, black carbon (BC) and ultrafine particles (UFP) as well as the ambient BC concentrations. The fleet average emission factors for light-duty gasoline vehicles (LDGV) showed considerable reduction in the Olympic year (2008) compared to the pre-Olympic year (2007). Our measurement of Black Carbon (BC), a primary pollutant, at different elevations at the ambient site suggests consistent decrease in BC concentrations as the height increased near the ground level, which indicates that the nearby ground level sources, probably dominated by traffic, contributed to a large portion of BC concentrations in the lower atmospheric layer in Beijing during summertime. These observations indicate that people living in near ground levels experience higher exposures than those living in higher floors in Beijing. The BC diurnal patterns on days when traffic control were in place during the Olympic Games were compared to those on non-traffic-control days in both 2007 and in 2008. These patterns strongly suggest that diesel trucks are a major source of summertime BC in Beijing. The median BC concentration on Olympic days was 3.7 μg m -3, which was dramatically lower than the value on non-traffic-control days, indicating the effectiveness of traffic control regulations in BC reduction in Beijing.

  20. New emission factors for Australian vegetation fires measured using open-path Fourier transform infrared spectroscopy - Part 2: Australian tropical savanna fires

    NASA Astrophysics Data System (ADS)

    Smith, T. E. L.; Paton-Walsh, C.; Meyer, C. P.; Cook, G. D.; Maier, S. W.; Russell-Smith, J.; Wooster, M. J.; Yates, C. P.

    2014-10-01

    Savanna fires contribute approximately 40-50% of total global annual biomass burning carbon emissions. Recent comparisons of emission factors from different savanna regions have highlighted the need for a regional approach to emission factor development, and better assessment of the drivers of the temporal and spatial variation in emission factors. This paper describes the results of open-path Fourier transform infrared (OP-FTIR) spectroscopic field measurements at 21 fires occurring in the tropical savannas of the Northern~Territory, Australia, within different vegetation assemblages and at different stages of the dry season. Spectra of infrared light passing through a long (22-70 m) open-path through ground-level smoke released from these fires were collected using an infrared lamp and a field-portable FTIR system. The IR spectra were used to retrieve the mole fractions of 14 different gases present within the smoke, and these measurements used to calculate the emission ratios and emission factors of the various gases emitted by the burning. Only a handful of previous emission factor measures are available specifically for the tropical savannas of Australia and here we present the first reported emission factors for methanol, acetic acid, and formic acid for this biome. Given the relatively large sample size, it was possible to study the potential causes of the within-biome variation of the derived emission factors. We find that the emission factors vary substantially between different savanna vegetation assemblages; with a majority of this variation being mirrored by variations in the modified combustion efficiency (MCE) of different vegetation classes. We conclude that a significant majority of the variation in the emission factor for trace gases can be explained by MCE, irrespective of vegetation class, as illustrated by variations in the calculated methane emission factor for different vegetation classes using data sub-set by different combustion efficiencies

  1. An integrated analytical framework for quantifying the LCOE of waste-to-energy facilities for a range of greenhouse gas emissions policy and technical factors.

    PubMed

    Townsend, Aaron K; Webber, Michael E

    2012-07-01

    This study presents a novel integrated method for considering the economics of waste-to-energy (WTE) facilities with priced greenhouse gas (GHG) emissions based upon technical and economic characteristics of the WTE facility, MSW stream, landfill alternative, and GHG emissions policy. The study demonstrates use of the formulation for six different policy scenarios and explores sensitivity of the results to ranges of certain technical parameters as found in existing literature. The study shows that details of the GHG emissions regulations have large impact on the levelized cost of energy (LCOE) of WTE and that GHG regulations can either increase or decrease the LCOE of WTE depending on policy choices regarding biogenic fractions from combusted waste and emissions from landfills. Important policy considerations are the fraction of the carbon emissions that are priced (i.e. all emissions versus only non-biogenic emissions), whether emissions credits are allowed due to reducing fugitive landfill gas emissions, whether biogenic carbon sequestration in landfills is credited against landfill emissions, and the effectiveness of the landfill gas recovery system where waste would otherwise have been buried. The default landfill gas recovery system effectiveness assumed by much of the industry yields GHG offsets that are very close to the direct non-biogenic GHG emissions from a WTE facility, meaning that small changes in the recovery effectiveness cause relatively larger changes in the emissions factor of the WTE facility. Finally, the economics of WTE are dependent on the MSW stream composition, with paper and wood being advantageous, metal and glass being disadvantageous, and plastics, food, and yard waste being either advantageous or disadvantageous depending upon the avoided tipping fee and the GHG emissions price. PMID:22425189

  2. An integrated analytical framework for quantifying the LCOE of waste-to-energy facilities for a range of greenhouse gas emissions policy and technical factors.

    PubMed

    Townsend, Aaron K; Webber, Michael E

    2012-07-01

    This study presents a novel integrated method for considering the economics of waste-to-energy (WTE) facilities with priced greenhouse gas (GHG) emissions based upon technical and economic characteristics of the WTE facility, MSW stream, landfill alternative, and GHG emissions policy. The study demonstrates use of the formulation for six different policy scenarios and explores sensitivity of the results to ranges of certain technical parameters as found in existing literature. The study shows that details of the GHG emissions regulations have large impact on the levelized cost of energy (LCOE) of WTE and that GHG regulations can either increase or decrease the LCOE of WTE depending on policy choices regarding biogenic fractions from combusted waste and emissions from landfills. Important policy considerations are the fraction of the carbon emissions that are priced (i.e. all emissions versus only non-biogenic emissions), whether emissions credits are allowed due to reducing fugitive landfill gas emissions, whether biogenic carbon sequestration in landfills is credited against landfill emissions, and the effectiveness of the landfill gas recovery system where waste would otherwise have been buried. The default landfill gas recovery system effectiveness assumed by much of the industry yields GHG offsets that are very close to the direct non-biogenic GHG emissions from a WTE facility, meaning that small changes in the recovery effectiveness cause relatively larger changes in the emissions factor of the WTE facility. Finally, the economics of WTE are dependent on the MSW stream composition, with paper and wood being advantageous, metal and glass being disadvantageous, and plastics, food, and yard waste being either advantageous or disadvantageous depending upon the avoided tipping fee and the GHG emissions price.

  3. An integrated analytical framework for quantifying the LCOE of waste-to-energy facilities for a range of greenhouse gas emissions policy and technical factors

    SciTech Connect

    Townsend, Aaron K.; Webber, Michael E.

    2012-07-15

    This study presents a novel integrated method for considering the economics of waste-to-energy (WTE) facilities with priced greenhouse gas (GHG) emissions based upon technical and economic characteristics of the WTE facility, MSW stream, landfill alternative, and GHG emissions policy. The study demonstrates use of the formulation for six different policy scenarios and explores sensitivity of the results to ranges of certain technical parameters as found in existing literature. The study shows that details of the GHG emissions regulations have large impact on the levelized cost of energy (LCOE) of WTE and that GHG regulations can either increase or decrease the LCOE of WTE depending on policy choices regarding biogenic fractions from combusted waste and emissions from landfills. Important policy considerations are the fraction of the carbon emissions that are priced (i.e. all emissions versus only non-biogenic emissions), whether emissions credits are allowed due to reducing fugitive landfill gas emissions, whether biogenic carbon sequestration in landfills is credited against landfill emissions, and the effectiveness of the landfill gas recovery system where waste would otherwise have been buried. The default landfill gas recovery system effectiveness assumed by much of the industry yields GHG offsets that are very close to the direct non-biogenic GHG emissions from a WTE facility, meaning that small changes in the recovery effectiveness cause relatively larger changes in the emissions factor of the WTE facility. Finally, the economics of WTE are dependent on the MSW stream composition, with paper and wood being advantageous, metal and glass being disadvantageous, and plastics, food, and yard waste being either advantageous or disadvantageous depending upon the avoided tipping fee and the GHG emissions price.

  4. An accelerated ordered subsets reconstruction algorithm using an accelerating power factor for emission tomography

    NASA Astrophysics Data System (ADS)

    Hsiao, Ing-Tsung; Huang, Hsuan-Ming

    2010-02-01

    We proposed a speed-enhanced tomographic reconstruction algorithm, ACOSEM (accelerated complete-data ordered-subset expectation-maximization), to accelerate a convergent OS-type algorithm (COSEM). The ACOSEM algorithm was based on modification of the COSEM update by applying an accelerating power factor or a bigger step size. Unlike the limited enhancement of the other speed-enhanced algorithm (E-COSEM), the proposed ACOSEM with an appropriate power factor can lead to a much faster reconstruction speed than COSEM and ECOSEM. Similar to COSEM, there is no free user-entered relaxation parameter needed for ACOSEM to ensure the convergent performance as required in the other type of fast convergent algorithms such as RAMLA. We derived the ACOSEM algorithm, and compared its performance to those of other fast convergent algorithms including COSEM, ECOSEM and RAMLA with optimized relaxation parameters. Though not convergent, OSEM is the current state-of-the-art reconstruction method used in the clinics, and thus included in the noise performance comparison. The results showed that ACOSEM reached the same image quality as in COSEM but two times faster when a power factor of 2.0 was used. An upper limit of 5 for the power factor with monotonically increasing log-likelihood in ACOSEM was observed under various conditions. Although the convergence proof is not available now, the results of log-likelihood values and noise studies showed that ACOSEM performed consistently with COSEM but with an accelerating reconstruction speed.

  5. New emission factors for Australian vegetation fires measured using open-path Fourier transform infrared spectroscopy - Part 2: Australian tropical savanna fires

    NASA Astrophysics Data System (ADS)

    Smith, T. E. L.; Paton-Walsh, C.; Meyer, C. P.; Cook, G. D.; Maier, S. W.; Russell-Smith, J.; Wooster, M. J.; Yates, C. P.

    2014-03-01

    Savanna fires contribute approximately 40-50% of total global annual biomass burning carbon emissions. Recent comparisons of emission factors from different savanna regions have highlighted the need for a regional approach to emission factor development, and better assessment of the drivers of the temporal and spatial variation in emission factors. This paper describes the results of open-path Fourier Transform Infrared (OP-FTIR) spectroscopic field measurements at twenty-one fires occurring in the tropical savannas of the Northern Territory, Australia, within different vegetation assemblages and at different stages of the dry season. Spectra of infrared light passing through a long (22-70 m) open-path through ground-level smoke released from these fires were collected using an infrared lamp and a field-portable FTIR system. The IR spectra were used to retrieve the mole fractions of fourteen different gases present within the smoke, and these measurements used to calculate the emission ratios and emission factors of the various gases emitted by the burning. Only a handful of previous emission factor measures are available specifically for the tropical savannas of Australia and here we present the first reported emission factors for methanol, acetic acid, and formic acid for this biome. Given the relatively large sample size, it was possible to study the potential causes of the within-biome variation of the derived emission factors. We find that the emission factors vary substantially between different savanna vegetation assemblages; with a majority of this variation being mirrored by variations in the modified combustion efficiency (MCE) of different vegetation classes. We conclude that a significant majority of the variation in the emission factor for trace gases can be explained by MCE, irrespective of vegetation class, as illustrated by variations in the calculated methane emission factor for different vegetation classes using data subsetted by different

  6. Towards an improved inventory of N2O from agriculture: Model evaluation of N2O emission factors and N fraction leached from different sources in UK agriculture

    NASA Astrophysics Data System (ADS)

    Cardenas, L. M.; Gooday, R.; Brown, L.; Scholefield, D.; Cuttle, S.; Gilhespy, S.; Matthews, R.; Misselbrook, T.; Wang, J.; Li, C.; Hughes, G.; Lord, E.

    2013-11-01

    National and international requirements for greenhouse gas emissions demand the development of more accurate inventories and mitigation options that are effective in reducing emissions. The UK government set a target for the year 2050 of an 80% reduction in greenhouse gas emissions compared to the 1990 baseline. Estimate of UK national emissions is based on IPCC default methodology and as agriculture contributes about 7% of total GHG emissions of which 60% is N2O, efforts to improve the inventory and assess mitigation options are needed. Models can be used to derive N2O emission factors providing high spatial and temporal resolution. In this study, we used two models, the UK-DNDC, a mechanistic model to estimate N2O emissions from soils and the NITCAT model to estimate the fraction of N applied that is leached and causes indirect emissions, both at county level for the UK. Four mitigation options were assessed and the results showed there were differences in the emission factors according to location. Average emission factors for N2O from soils for inorganic fertiliser did not differ from the IPCC default value but for organic fertiliser the model gave much lower values. FracLEACH for arable land was higher than that for grassland (UK averages of 0.28 and 0.09 respectively) and the national average value was 0.18. For N2O, the most effective mitigation measure was adjusting fertiliser rates to account for crop available manure N. For N leaching, the most effective measure was implementation of a manure closed period.

  7. 40 CFR Table 1 to Subpart Wwww of... - Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 13 2012-07-01 2012-07-01 false Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal Casting Process Streams 1 Table 1 to Subpart... Factors for Specific Open Molding and Centrifugal Casting Process Streams ER25AU05.020 ER25AU05.021...

  8. 40 CFR Table 1 to Subpart Wwww of... - Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 13 2014-07-01 2014-07-01 false Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal Casting Process Streams 1 Table 1 to Subpart... Factors for Specific Open Molding and Centrifugal Casting Process Streams ER25AU05.020 ER25AU05.021...

  9. 40 CFR Table 1 to Subpart Wwww of... - Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 13 2013-07-01 2012-07-01 true Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal Casting Process Streams 1 Table 1 to Subpart... Factors for Specific Open Molding and Centrifugal Casting Process Streams ER25AU05.020 ER25AU05.021...

  10. Development of net energy ratio and emission factor for biohydrogen production pathways.

    PubMed

    Kabir, Md Ruhul; Kumar, Amit

    2011-10-01

    This study investigates the energy and environmental aspects of producing biohydrogen for bitumen upgrading from a life cycle perspective. Three technologies are studied for biohydrogen production; these include the Battelle Columbus Laboratory (BCL) gasifier, the Gas Technology Institute (GTI) gasifier, and fast pyrolysis. Three different biomass feedstocks are considered including forest residue (FR), whole forest (WF), and agricultural residue (AR). The fast pyrolysis pathway includes two cases: truck transport of bio-oil and pipeline transport of bio-oil. The net energy ratios (NERs) for nine biohydrogen pathways lie in the range of 1.3-9.3. The maximum NER (9.3) is for the FR-based pathway using GTI technology. The GHG emissions lie in the range of 1.20-8.1 kg CO₂ eq/kg H₂. The lowest limit corresponds to the FR-based biohydrogen production pathway using GTI technology. This study also analyzes the intensities for acid rain precursor and ground level ozone precursor.

  11. Heating medium absorption and emission as factors in thermographic investigations of petrochemical furnaces

    NASA Astrophysics Data System (ADS)

    Pregowski, P.; Goleniewski, G.; Komosa, W.; Korytkowski, W.; Zwolenik, Sl.

    2009-05-01

    This paper presents the current state of our efforts to increase efficiency of petrochemical plant with using spectral-band dynamic IR radiation thermometry. Depending on the type of investigations i.e. studying tubes' temperature, what is the most typical and important case or studying energetic and dynamic features of the flames and flue gases, different narrow-band optical filters and research procedures have to be applied. To perform both type of these measurements we modernized commercial PtSi FPA camera and software to process various sequences of thermal images. Two of results are highlighted: possibilities to increase tube' temperature measurements confident and reliability due to minimization of errors going from mostly fluctuating reflections of surrounding heat sources and self-emissions of heating medium between tube and camera, as well as a new diagnostic potential of the images of chosen gases features, for comparative investigations in particular. Case histories, some challenges and limitations during elaborated method application have also been addressed.

  12. DEVELOPMENT OF AN EMISSION FACTOR FOR AMMONIA EMISSIONS FROM U.S. SWINE FARMS BASED ON FIELD TESTS AND APPLICATION OF A MASS BALANCE METHOD

    EPA Science Inventory

    This paper summarizes and discusses recent available U.S. and European information on
    ammonia (NH3) emissions from swine farms and assesses the applicability for general use
    in the United States. The emission rates for the swine barns calculated by various methods show
    g...

  13. Emission factor estimation of ca. 160 emerging organic microcontaminants by inverse modeling in a Mediterranean river basin (Llobregat, NE Spain).

    PubMed

    Banjac, Zoran; Ginebreda, Antoni; Kuzmanovic, Maja; Marcé, Rafael; Nadal, Martí; Riera, Josep M; Barceló, Damià

    2015-07-01

    Starting from measured river concentrations, emission factors of 158 organic compounds out of 199 analyzed belonging to different groups of priority and emerging contaminants [pesticides (25), pharmaceuticals and hormones (81), perfluoroalkyl substances (PFASs) (18), industrial compounds (12), drugs of abuse (8) and personal care products (14)] have been estimated by inverse modeling. The Llobregat river was taken as case study representative of Mediterranean rivers. Industrial compounds and pharmaceuticals are the dominant groups (range of 10(4) mg·1000 inhab(-1)·d(-1)). Personal care products, pesticides, PFASs and illegal drugs showed a load approximately one order of magnitude smaller. Considered on a single compound basis industrial compounds still dominate (range of ca. 10(3) mg·1000 inhab(-1)·d(-1)) over other classes. Generally, the results are within the range when compared to previously published estimations for other river basins. River attenuation expressed as the percentage fraction of microcontaminants eliminated was quantified. On average they were around 60-70% of the amount discharged for all classes, except for PFASs, that are poorly eliminated (ca. 20% on average). Uncertainties associated with the calculated emissions have been estimated by Monte-Carlo methods (15,000 runs) and typically show coefficients of variation of ca. 120%. Sensitivities associated with the various variables involved in the calculations (river discharge, river length, concentration, elimination constant, hydraulic travel time and river velocity) have been assessed as well. For the intervals chosen for the different variables, all show sensitivities exceeding unity (1.14 to 3.43), tending to amplify the variation of the emission. River velocity and basin length showed the highest sensitivity value. Even considering the limitations of the approach used, inverse modeling can provide a useful tool for management purposes facilitating the quantification of release rates of

  14. Evaluation of Uncertainties in Measuring Particulate Matter Emission Factors from Atmospheric Fugitive Sources Using Optical Remote Sensing

    NASA Astrophysics Data System (ADS)

    Yuen, W.; Ma, Q.; Du, K.; Koloutsou-Vakakis, S.; Rood, M. J.

    2015-12-01

    Measurements of particulate matter (PM) emissions generated from fugitive sources are of interest in air pollution studies, since such emissions vary widely both spatially and temporally. This research focuses on determining the uncertainties in quantifying fugitive PM emission factors (EFs) generated from mobile vehicles using a vertical scanning micro-pulse lidar (MPL). The goal of this research is to identify the greatest sources of uncertainty of the applied lidar technique in determining fugitive PM EFs, and to recommend methods to reduce the uncertainties in this measurement. The MPL detects the PM plume generated by mobile fugitive sources that are carried downwind to the MPL's vertical scanning plane. Range-resolved MPL signals are measured, corrected, and converted to light extinction coefficients, through inversion of the lidar equation and calculation of the lidar ratio. In this research, both the near-end and far-end lidar equation inversion methods are considered. Range-resolved PM mass concentrations are then determined from the extinction coefficient measurements using the measured mass extinction efficiency (MEE) value, which is an intensive PM property. MEE is determined by collocated PM mass concentration and light extinction measurements, provided respectively by a DustTrak and an open-path laser transmissometer. These PM mass concentrations are then integrated with wind information, duration of plume event, and vehicle distance travelled to obtain fugitive PM EFs. To obtain the uncertainty of PM EFs, uncertainties in MPL signals, lidar ratio, MEE, and wind variation are considered. Error propagation method is applied to each of the above intermediate steps to aggregate uncertainty sources. Results include determination of uncertainties in each intermediate step, and comparison of uncertainties between the use of near-end and far-end lidar equation inversion methods.

  15. Development of methane emission factors for enteric fermentation in cattle from Benin using IPCC Tier 2 methodology.

    PubMed

    Kouazounde, J B; Gbenou, J D; Babatounde, S; Srivastava, N; Eggleston, S H; Antwi, C; Baah, J; McAllister, T A

    2015-03-01

    The objective of this study was to develop emission factors (EF) for methane (CH4) emissions from enteric fermentation in cattle native to Benin. Information on livestock characteristics and diet practices specific to the Benin cattle population were gathered from a variety of sources and used to estimate EF according to Tier 2 methodology of the 2006 Intergovernmental Panel on Climate Change (IPCC) Guidelines for National Greenhouse Gas Inventories. Most cattle from Benin are Bos taurus represented by Borgou, Somba and Lagune breeds. They are mainly multi-purpose, being used for production of meat, milk, hides and draft power and grazed in open pastures and crop lands comprising tropical forages and crops. Estimated enteric CH4 EFs varied among cattle breeds and subcategory owing to differences in proportions of gross energy intake expended to meet maintenance, production and activity. EFs ranged from 15.0 to 43.6, 16.9 to 46.3 and 24.7 to 64.9 kg CH4/head per year for subcategories of Lagune, Somba and Borgou cattle, respectively. Average EFs for cattle breeds were 24.8, 29.5 and 40.2 kg CH4/head per year for Lagune, Somba and Borgou cattle, respectively. The national EF for cattle from Benin was 39.5 kg CH4/head per year. This estimated EF was 27.4% higher than the default EF suggested by IPCC for African cattle with the exception of dairy cattle. The outcome of the study underscores the importance of obtaining country-specific EF to estimate global enteric CH4 emissions. PMID:25385068

  16. Generation rates and emission factors of particulate matter and particle-bound polycyclic aromatic hydrocarbons of incense sticks.

    PubMed

    Lung, Shih-Chun Candice; Hu, Shu-Chuan

    2003-02-01

    The generation rates and emission factors of particulate matter and associated polycyclic aromatic hydrocarbons (PAHs) from incense burning were assessed in a laboratory setting. The differences among different segments of the same stick, among different sticks of the same kind of incense, and between two kinds of manually made Chih-Chen incense sticks (A and B) were evaluated. Joss sticks were burned inside a 44 cm long elutriator; personal environmental monitors fitted into the top of the elutriator were used to take PM2.5 and PM10 samples of incense smoke. Samples were analyzed for PAHs by gas chromatography-flame ionization Detector. It was found that particle and associated PAHs were generated approximately at 561 microg/min (geometric standard deviation (GSD) = 1.1) and 0.56 microg/min (GSD = 1.1) from Incense A, and at 661 microg/min (GSD = 1.7) and 0.46 microg/min (GSD = 1.3) from Incense B, respectively. One gram of Incense A emitted about 19.8 mg (GSD = 1.1) particulate matter and 17.1 microg (GSD = 1.2) particulate-phase PAHs, while one gram of Incense B produced around 43.6 mg (GSD = 1.1) of particles and 25.2 microg (GSD = 1.2) of particle-bound PAHs. There were significant differences in emissions between Incenses A and B, although they belong to the same class of incense. A 10-20% variability in emissions was observed in the main part of the manually produced stick, and a larger variation was found at both tips of the combustible part.

  17. Emission factor estimation of ca. 160 emerging organic microcontaminants by inverse modeling in a Mediterranean river basin (Llobregat, NE Spain).

    PubMed

    Banjac, Zoran; Ginebreda, Antoni; Kuzmanovic, Maja; Marcé, Rafael; Nadal, Martí; Riera, Josep M; Barceló, Damià

    2015-07-01

    Starting from measured river concentrations, emission factors of 158 organic compounds out of 199 analyzed belonging to different groups of priority and emerging contaminants [pesticides (25), pharmaceuticals and hormones (81), perfluoroalkyl substances (PFASs) (18), industrial compounds (12), drugs of abuse (8) and personal care products (14)] have been estimated by inverse modeling. The Llobregat river was taken as case study representative of Mediterranean rivers. Industrial compounds and pharmaceuticals are the dominant groups (range of 10(4) mg·1000 inhab(-1)·d(-1)). Personal care products, pesticides, PFASs and illegal drugs showed a load approximately one order of magnitude smaller. Considered on a single compound basis industrial compounds still dominate (range of ca. 10(3) mg·1000 inhab(-1)·d(-1)) over other classes. Generally, the results are within the range when compared to previously published estimations for other river basins. River attenuation expressed as the percentage fraction of microcontaminants eliminated was quantified. On average they were around 60-70% of the amount discharged for all classes, except for PFASs, that are poorly eliminated (ca. 20% on average). Uncertainties associated with the calculated emissions have been estimated by Monte-Carlo methods (15,000 runs) and typically show coefficients of variation of ca. 120%. Sensitivities associated with the various variables involved in the calculations (river discharge, river length, concentration, elimination constant, hydraulic travel time and river velocity) have been assessed as well. For the intervals chosen for the different variables, all show sensitivities exceeding unity (1.14 to 3.43), tending to amplify the variation of the emission. River velocity and basin length showed the highest sensitivity value. Even considering the limitations of the approach used, inverse modeling can provide a useful tool for management purposes facilitating the quantification of release rates of

  18. Coupling field and laboratory measurements to estimate the emission factors of identified and unidentified trace gases for prescribed fires

    NASA Astrophysics Data System (ADS)

    Yokelson, R. J.; Burling, I. R.; Gilman, J. B.; Warneke, C.; Stockwell, C. E.; de Gouw, J.; Akagi, S. K.; Urbanski, S. P.; Veres, P.; Roberts, J. M.; Kuster, W. C.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Hosseini, S.; Miller, J. W.; Cocker, D. R., III; Jung, H.; Weise, D. R.

    2013-01-01

    An extensive program of experiments focused on biomass burning emissions began with a laboratory phase in which vegetative fuels commonly consumed in prescribed fires were collected in the southeastern and southwestern US and burned in a series of 71 fires at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The particulate matter (PM2.5) emissions were measured by gravimetric filter sampling with subsequent analysis for elemental carbon (EC), organic carbon (OC), and 38 elements. The trace gas emissions were measured by an open-path Fourier transform infrared (OP-FTIR) spectrometer, proton-transfer-reaction mass spectrometry (PTR-MS), proton-transfer ion-trap mass spectrometry (PIT-MS), negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), and gas chromatography with MS detection (GC-MS). 204 trace gas species (mostly non-methane organic compounds (NMOC)) were identified and quantified with the above instruments. Many of the 182 species quantified by the GC-MS have rarely, if ever, been measured in smoke before. An additional 153 significant peaks in the unit mass resolution mass spectra were quantified, but either could not be identified or most of the signal at that molecular mass was unaccounted for by identifiable species. In a second, "field" phase of this program, airborne and ground-based measurements were made of the emissions from prescribed fires that were mostly located in the same land management units where the fuels for the lab fires were collected. A broad variety, but smaller number of species (21 trace gas species and PM2.5) was measured on 14 fires in chaparral and oak savanna in the southwestern US, as well as pine forest understory in the southeastern US and Sierra Nevada mountains of California. The field measurements of emission factors (EF) are useful both for modeling and to examine the representativeness of our lab fire EF. The lab EF/field EF ratio for the pine understory fuels was not

  19. Coupling field and laboratory measurements to estimate the emission factors of identified and unidentified trace gases for prescribed fires

    NASA Astrophysics Data System (ADS)

    Yokelson, R. J.; Burling, I. R.; Gilman, J. B.; Warneke, C.; Stockwell, C. E.; de Gouw, J.; Akagi, S. K.; Urbanski, S. P.; Veres, P.; Roberts, J. M.; Kuster, W. C.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Hosseini, S.; Miller, J. W.; Cocker, D. R., III; Jung, H.; Weise, D. R.

    2012-08-01

    An extensive program of experiments focused on biomass burning emissions began with a laboratory phase in which vegetative fuels commonly consumed in prescribed fires were collected in the southeastern and southwestern US and burned in a series of 71 fires at the US Forest Service Fire Sciences Laboratory in Missoula, Montana. The particulate matter (PM2.5) emissions were measured by gravimetric filter sampling with subsequent analysis for elemental carbon (EC), organic carbon (OC), and 38 elements. The trace gas emissions were measured by an open-path Fourier transform infrared (OP-FTIR) spectrometer, proton-transfer-reaction mass spectrometry (PTR-MS), proton-transfer ion-trap mass spectrometry (PIT-MS), negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), and gas chromatography with MS detection (GC-MS). 204 trace gas species (mostly non-methane organic compounds - NMOC) were identified and quantified with the above instruments. Many of the 182 species quantified by the GC-MS have rarely, if ever, been measured in smoke before. An additional 153 significant peaks in the unit mass resolution mass spectra were quantified, but either could not be identified or most of the signal at that molecular mass was unaccounted for by identifiable species. In a second, "field" phase of this program, airborne and ground-based measurements were made of the emissions from prescribed fires that were mostly located in the same land management units where the fuels for the lab fires were collected. A broad variety, but smaller number of species (21 trace gas species and PM2.5) was measured on 14 fires in chaparral and oak savanna in the southwestern US, as well as pine forest understory in the southeastern US and Sierra Nevada mountains of California. The field measurements of emission factors (EF) are useful both for modeling and to examine the representativeness of our lab fire EF. The lab EF/field EF ratio for the pine understory fuels was not

  20. Emission factors and particulate matter size distribution of polycyclic aromatic hydrocarbons from residential coal combustions in rural Northern China

    NASA Astrophysics Data System (ADS)

    Shen, Guofeng; Wang, Wei; Yang, Yifeng; Zhu, Chen; Min, Yujia; Xue, Miao; Ding, Junnan; Li, Wei; Wang, Bin; Shen, Huizhong; Wang, Rong; Wang, Xilong; Tao, Shu

    2010-12-01

    Coal consumption is one important contributor to energy production, and is regarded as one of the most important sources of air pollutants that have considerable impacts on human health and climate change. Emissions of polycyclic aromatic hydrocarbons (PAHs) from coal combustion were studied in a typical stove. Emission factors (EFs) of 16 EPA priority PAHs from tested coals ranged from 6.25 ± 1.16 mg kg -1 (anthracite) to 253 ± 170 mg kg -1 (bituminous), with NAP and PHE dominated in gaseous and particulate phases, respectively. Size distributions of particulate phase PAHs from tested coals showed that they were mostly associated with particulate matter (PM) with size either between 0.7 and 2.1 μm or less than 0.4 μm (PM 0.4). In the latter category, not only were more PAHs present in PM 0.4, but also contained higher fractions of high molecular weight PAHs. Generally, there were more than 89% of total particulate phase PAHs associated with PM 2.5. Gas-particle partitioning of freshly emitted PAHs from residential coal combustions were thought to be mainly controlled by absorption rather than adsorption, which is similar to those from other sources. Besides, the influence of fuel properties and combustion conditions was further investigated by using stepwise regression analysis, which indicated that almost 57 ± 10% of total variations in PAH EFs can be accounted for by moisture and volatile matter content of coal in residential combustion.

  1. Land and Water Use, CO2 Emissions, and Worker Radiological Exposure Factors for the Nuclear Fuel Cycle

    SciTech Connect

    Brett W Carlsen; Brent W Dixon; Urairisa Pathanapirom; Eric Schneider; Bethany L. Smith; Timothy M. AUlt; Allen G. Croff; Steven L. Krahn

    2013-08-01

    The Department of Energy Office of Nuclear Energy’s Fuel Cycle Technologies program is preparing to evaluate several proposed nuclear fuel cycle options to help guide and prioritize Fuel Cycle Technology research and development. Metrics are being developed to assess performance against nine evaluation criteria that will be used to assess relevant impacts resulting from all phases of the fuel cycle. This report focuses on four specific environmental metrics. • land use • water use • CO2 emissions • radiological Dose to workers Impacts associated with the processes in the front-end of the nuclear fuel cycle, mining through enrichment and deconversion of DUF6 are summarized from FCRD-FCO-2012-000124, Revision 1. Impact estimates are developed within this report for the remaining phases of the nuclear fuel cycle. These phases include fuel fabrication, reactor construction and operations, fuel reprocessing, and storage, transport, and disposal of associated used fuel and radioactive wastes. Impact estimates for each of the phases of the nuclear fuel cycle are given as impact factors normalized per unit process throughput or output. These impact factors can then be re-scaled against the appropriate mass flows to provide estimates for a wide range of potential fuel cycles. A companion report, FCRD-FCO-2013-000213, applies the impact factors to estimate and provide a comparative evaluation of 40 fuel cycles under consideration relative to these four environmental metrics.

  2. Field enhancement factor and field emission from a hemi-ellipsoidal metallic needle.

    PubMed

    Pogorelov, Evgeny G; Zhbanov, Alexander I; Chang, Yia-Chung

    2009-03-01

    We present an exact solution for the electrostatic field between a metallic hemi-ellipsoidal needle on a plate (as a cathode) and a flat anode. The basic idea is to replace the cathode by a linearly charged thread in a uniform electric field and to use a set of "image" charges to reproduce the anode. We calculate the field enhancement factor on the needle surface and ponderomotive force acting on the needle. Using the Fowler-Nordheim theory we obtain an exact analytical formula for the total current. PMID:19232831

  3. Real-world PM, NO x, CO, and ultrafine particle emission factors for military non-road heavy duty diesel vehicles

    NASA Astrophysics Data System (ADS)

    Zhu, Dongzi; Nussbaum, Nicholas J.; Kuhns, Hampden D.; Chang, M.-C. Oliver; Sodeman, David; Moosmüller, Hans; Watson, John G.

    2011-05-01

    Training on US military bases involves nonroad diesel vehicles with emissions that can affect base personnel, nearby communities, and attainment of air quality standards. Nonroad diesel engines contribute 44% of diesel PM and 12% of total NO x emissions from mobile sources nationwide. Although military sector fuel use accounts for only ≈0.4% of distillate fuel use in US, emissions factors measured for these engines improve the representation of the relatively small (as compared to onroad sources) database of nonroad emission factors. Heavy-duty multi-axle, all-wheel drive military trucks are not compatible with regular single-axle dynamometers and their emissions cannot be measured under standard laboratory conditions. We have developed a novel in-plume technique to measure in-use emissions from vehicles with elevated stack. Real-world gaseous and particulate matter (PM) emission factors (EFs) from ten 7-ton 6-wheel drive trucks and two 8-wheel drive heavy tactical Logistics Vehicle System (LVS) vehicles were measured using in-plume sampling. The EFs of these trucks are comparable to those of onroad trucks while the PM EFs of 2-stroke LVS are ≈10 times higher than those of onroad vehicles. Lower EC/PM ratio was observed for LVS compared with MTVR. PM number emission factors were 5.9 × 10 14 particles km -1 for the trucks and 2.5 × 10 16 particles km -1 for the LVSs, three orders of magnitude higher than the proposed European Union standard of 6 × 10 11 particles km -1. The EFs sampled can be extended to engines used in the broader nonroad sector including agriculture and mining and used as inputs to the NONROAD model.

  4. 40 CFR Table I-8 to Subpart I of... - Default Emission Factors (1-UN2O,j) for N2O Utilization (UN2O,j)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Emission Factors (1-UN2O,j) for N2O Utilization (UN2O,j) I Table I-8 to Subpart I of Part 98 Protection of Environment... Factors (1-UN2O,j) for N2O Utilization (UN2O,j) Process type factors N2O CVD 1-Ui 0.8 Other...

  5. 40 CFR Table I-8 to Subpart I of... - Default Emission Factors (1-UN2O j) for N2O Utilization (UN2O j)

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Default Emission Factors (1-UN2O j) for N2O Utilization (UN2O j) I Table I-8 to Subpart I of Part 98 Protection of Environment... Factors (1-UN 2 O j) for N2O Utilization (UN2 O j) Process type factors N2O CVD 1-Ui 0.8...

  6. DEVELOPMENT OF REAL-TIME SITE-SPECIFIC MICROSCALE EMISSION FACTOR MODEL FOR THE ASSESSMENT OF HUMAN EXPOSURE TO MOTOR VEHICLE EMISSIONS

    EPA Science Inventory

    The United States Environmental Protection Agency's (EPA) National Expsoure Research Laboratory (NERL) has initiated a project to improve the methodology for modeling urban-scale human exposure to mobile source emissions. The modeling project has started by considering the nee...

  7. Effects of endogenous factors on regional land-use carbon emissions based on the Grossman decomposition model: a case study of Zhejiang Province, China.

    PubMed

    Wu, Cifang; Li, Guan; Yue, Wenze; Lu, Rucheng; Lu, Zhangwei; You, Heyuan

    2015-02-01

    The impact of land-use change on greenhouse gas emissions has become a core issue in current studies on global change and carbon cycle. However, a comprehensive evaluation of the effects of land-use changes on carbon emissions is very necessary. This paper attempted to apply the Grossman decomposition model to estimate the scale, structural, and management effects of land-use carbon emissions based on final energy consumption by establishing the relationship between the types of land use and carbon emissions in energy consumption. It was shown that land-use carbon emissions increase from 169.5624 million tons in 2000 to 637.0984 million tons in 2010, with an annual average growth rate of 14.15%. Meanwhile, land-use carbon intensity increased from 17.59 t/ha in 2000 to 64.42 t/ha in 2010, with an average annual growth rate of 13.86%. The results indicated that rapid industrialization and urbanization in Zhejiang Province promptly increased urban land and industrial land, which consequently affected land-use extensive emissions. The structural and management effects did not mitigate land-use carbon emissions. By contrast, both factors evidently affected the growth of carbon emissions because of the rigid demands of energy-intensive land-use types and the absence of land management. Results called for the policy implications of optimizing land-use structures and strengthening land-use management.

  8. Coupling field and laboratory measurements to estimate the emission factors of identified and unidentified trace gases for prescribed fires

    SciTech Connect

    Yokelson, R. J.; Burling, I. R.; Gilman, J. B.; Warneke, C.; Stockwell, C. E.; de Gouw, J.; Akagi, S. K.; Urbanski, S. P.; Veres, P.; Roberts, J. M.; Kuster, W. C.; Reardon, J.; Griffith, D. W. T.; Johnson, T. J.; Hosseini, S.; Miller, J. W.; Cocker III, D. R.; Jung, H.; Weise, D. R.

    2013-01-01

    Vegetative fuels commonly consumed in prescribed fires were collected from five locations in the southeastern and southwestern U.S. and burned in a series of 77 fires at the U.S. Forest Service Fire Sciences Laboratory in Missoula, Montana. The particulate matter (PM2.5) emissions were measured by gravimetric filter sampling with subsequent analysis for elemental carbon (EC), organic carbon (OC), and 38 elements. The trace gas emissions were measured with a large suite of state-of-the-art instrumentation including an open-path Fourier transform infrared (OP FTIR) spectrometer, proton-transfer-reaction mass spectrometry (PTR-MS), proton-transfer ion-trap mass spectrometry (PIT-MS), negative-ion proton-transfer chemical-ionization mass spectrometry (NI-PT-CIMS), and gas chromatography with MS detection (GC-MS). 204 trace gas species (mostly non-methane organic compounds (NMOC)) were identified and quantified with the above instruments. An additional 152 significant peaks in the unit mass resolution mass spectra were quantified, but either could not be identified or most of the signal at that molecular mass was unaccounted for by identifiable species. As phase II of this study, we conducted airborne and ground-based sampling of the emissions from real prescribed fires mostly in the same land management units where the fuels for the lab fires were collected. A broad variety, but smaller number of species (21 trace gas species and PM2.5) was measured on 14 fires in chaparral and oak savanna in the southwestern US, as well as pine forest understory in the southeastern US and Sierra Nevada mountains of California. These extensive field measurements of emission factors (EF) for temperate biomass burning are useful both for modeling and to examine the representativeness of our lab fire EF. The lab/field EF ratio for the pine understory fuels was not statistically different from one, on average. However, our lab EF for “smoldering compounds” emitted by burning the semi

  9. Source apportionment of PAHs in atmospheric particulates of Dalian: Factor analysis with nonnegative constraints and emission inventory analysis

    NASA Astrophysics Data System (ADS)

    Wan, Xianlie; Chen, Jingwen; Tian, Fulin; Sun, Weijun; Yang, Fenglin; Saiki, Kaoru

    Levels of 12 PAH species, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[e]pyrene, benzo[a]pyrene, perylene, indeno[1,2,3-cd]pyrene and benzo[ghi]perylene, in atmospheric particulates from urban area of Dalian, China, were determined. The sampling was performed at 15 sites in 1998. For wintertime and summertime, the summation of the 12 PAHs (ΣPAHs) averaged 167 (53.3-561) and 17.9 (1.6-48.9) ng m -3, respectively, which were much higher than the levels in other cities worldwide. Factor analysis with nonnegative constraints was used for source apportionment, which showed that PAHs originated from coal-related sources mainly (87%) and traffic emission as a second source (13%) in wintertime, and in summertime, coal-related sources (70%), traffic-related sources (27%), and wood burning (3%). The source apportionment results agree with the actual municipal and industrial layout well. Inventory analysis estimated the total amount of the 12 PAHs emitted by regulated stationary and mobile sources was 9940 kg in 1998. Qualitatively, consistent source apportionment results were obtained from the factor analysis with nonnegative constraints and inventory analysis.

  10. Air pollution from gas flaring: new emission factor estimates and detection in a West African aerosol remote-sensing climatology

    NASA Astrophysics Data System (ADS)

    MacKenzie, Rob; Fawole, Olusegun Gabriel; Levine, James; Cai, Xiaoming

    2016-04-01

    Gas flaring, the disposal of gas through stacks in an open-air flame, is a common feature in the processing of crude oil, especially in oil-rich regions of the world. Gas flaring is a prominent source of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAH), CO, CO2, nitrogen oxides (NOx), SO2 (in "sour" gas only), and soot (black carbon), as well as the release of locally significant amounts of heat. The rates of emission of these pollutants from gas flaring depend on a number of factors including, but not limited to, fuel composition and quantity, stack geometry, flame/combustion characteristics, and prevailing meteorological conditions. Here, we derive new estimated emission factors (EFs) for carbon-containing pollutants (excluding PAH). The air pollution dispersion model, ADMS5, is used to simulate the dispersion of the pollutants from flaring stacks in the Niger delta. A seasonal variation of the dispersion pattern of the pollutant within a year is studied in relation to the movements of the West Africa Monsoon (WAM) and other prevailing meteorological factors. Further, we have clustered AERONET aerosol signals using trajectory analysis to identify dominant aerosol sources at the Ilorin site in West Africa (4.34 oE, 8.32 oN). A 10-year trajectory-based analysis was undertaken (2005-2015, excluding 2010). Of particular interest are air masses that have passed through the gas flaring region in the Niger Delta area en-route the AERONET site. 7-day back trajectories were calculated using the UK Universities Global Atmospheric Modelling Programme (UGAMP) trajectory model which is driven by analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF). From the back-trajectory calculations, dominant sources are identified, using literature classifications: desert dust (DD); Biomass burning (BB); and Urban-Industrial (UI). We use a combination of synoptic trajectories and aerosol optical properties to distinguish a fourth source

  11. Characteristics of trace metals in traffic-derived particles in Hsuehshan Tunnel, Taiwan: size distribution, fingerprinting metal ratio, and emission factor

    NASA Astrophysics Data System (ADS)

    Lin, Y.-C.; Tsai, C.-J.; Wu, Y.-C.; Zhang, R.; Chi, K.-H.; Huang, Y.-T.; Lin, S.-H.; Hsu, S.-C.

    2014-05-01

    Traffic emissions are a significant source of airborne particulate matter (PM) in ambient environments. These emissions contain high abundance of toxic metals and thus pose adverse effects on human health. Size-fractionated aerosol samples were collected from May to September 2013 by using micro-orifice uniform deposited impactor (MOUDI). Sample collection was conducted simultaneously at the inlet and outlet sites of Hsuehshan Tunnel in northern Taiwan, which is the second longest freeway tunnel (12.9 km) in Asia. Such endeavor aims to characterize the chemical constituents, size distributions, and fingerprinting ratios, as well as the emission factors of particulate metals emitted by vehicle fleets. A total of 36 metals in size-resolved aerosols were determined through inductively coupled plasma mass spectrometry. Three major groups, namely, tailpipe emissions (Zn, Pb, and V), wear debris (Cu, Cd, Fe, Ga, Mn, Mo, Sb, and Sn), and resuspended dust (Ca, Mg, K, and Rb), of airborne PM metals were categorized on the basis of the results of enrichment factor, correlation matrix, and principal component analysis. Size distributions of wear-originated metals resembled the pattern of crustal elements, which were predominated by super-micron particulates (PM1-10). By contrast, tailpipe exhaust elements such as Zn, Pb, and V were distributed mainly in submicron particles. By employing Cu as a tracer of wear abrasion, several inter-metal ratios, including Fe/Cu (14), Ba/Cu (1.05), Sb/Cu (0.16), Sn/Cu (0.10), and Ga/Cu (0.03), served as fingerprints for wear debris. Emission factor of PM10 mass was estimated to be 7.7 mg vkm-1. The metal emissions were mostly predominated in super-micron particles (PM1-10). Finally, factors that possibly affect particulate metal emissions inside Hsuehshan Tunnel are discussed.

  12. Emission factors from aerial and ground measurements of field and laboratory forest burns in the southeastern US: PM2.5, black and brown carbon, VOC, and PCDD/PCDF.

    PubMed

    Aurell, Johanna; Gullett, Brian K

    2013-08-01

    Aerial- and ground-sampled emissions from three prescribed forest burns in the southeastern U.S. were compared to emissions from laboratory open burn tests using biomass from the same locations. A comprehensive array of emissions, including PM2.5, black carbon (BC), brown carbon (BrC), carbon dioxide (CO2), volatile organic compounds (VOCs), and polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were sampled using ground-based and aerostat-lofted platforms for determination of emission factors. The PM2.5 emission factors ranged from 14 to 47 g/kg biomass, up to three times higher than previously published studies. The biomass type was the primary determinant of PM2.5, rather than whether the emission sample was gathered from the laboratory or the field and from aerial- or ground-based sampling. The BC and BrC emission factors ranged from 1.2 to 2.1 g/kg biomass and 1.0 to 1.4 g/kg biomass, respectively. A decrease in BC and BrC emission factors with decreased combustion efficiency was found from both field and laboratory data. VOC emission factors increased with decreased combustion efficiency. No apparent differences in averaged emission factors were observed between the field and laboratory for BC, BrC, and VOCs. The average PCDD/PCDF emission factors ranged from 0.06 to 4.6 ng TEQ/kg biomass.

  13. A Comparison of Mass-Based Emission Factors from Laboratory Combustion of Boreal and Sub-Tropical Peat

    NASA Astrophysics Data System (ADS)

    Knue, J.; Yatavelli, R. L. N.; Chen, L. W. A. A.; Samburova, V.; Gyawali, M. S.; Watts, A.; Chakrabarty, R. K.; Moosmuller, H.; Wang, X.; Zielinska, B.; Chow, J. C.; Watson, J. G.; Tsibart, A.

    2014-12-01

    Peatlands cover approximately 3% of the Earth's surface, but account for approximately one-third of terrestrial soil carbon. This carbon is also much older, collected over hundreds to thousands of years, than other commonly encountered wildfire fuels such as Ponderosa Pine (i.e., years to decades). Due to the moisture and mineral content of peat it has a propensity to smolder, unlike Ponderosa Pine which has an intense flaming period when burning. To better understand the emission from peat fires, in comparison to Ponderosa Pine, a series of experiments were performed in the 8 m3 combustion chamber located at the Desert Research Institute in Reno, NV. Peat from Alaska and Florida (USA) and Siberia (Russia) were burned at two moisture content levels (25 & 50%). Ponderosa Pine needles from Sierra Nevada sites were burned at one moisture content level (8.2%). Real-time measurements included gaseous carbon monoxide (CO), carbon dioxide (CO2), oxides of nitrogen (NOx = NO + NO2), and ozone (O3) concentration, as well as particulate matter (PM) mass, size distribution, and black carbon concentration. In addition, Teflon-membrane and quartz-fiber filters as well as Teflon-impregnated glass fiber (TIGF) filters followed by XAD-4 cartridges were collected for detailed PM chemical speciation. Changes in fuel mass and combustion temperature were continuously monitored during each experiment. We will present a comparison of mass-based emission factors of inorganic gases, PM and black carbon mass concentrations, organic and elemental carbon, and a number of intermediate-volatility (300emissions will enable us to better forecast their impacts on local and regional

  14. Emission factors of SO2, NOx and particles from ships in Neva Bay from ground-based and helicopter-borne measurements and AIS-based modeling

    NASA Astrophysics Data System (ADS)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.; Johansson, L.; Litvinenko, V.; Volodin, K.; Frank-Kamenetsky, D. A.

    2015-05-01

    Emission factors of SO2, NOx and size-distributed particle numbers were measured for approximately 300 different ships in the Gulf of Finland and Neva Bay area during two campaigns in August/September 2011 and June/July 2012. The measurements were carried out from a harbor vessel and from an Mi-8 helicopter downwind of passing ships. Other measurements were carried out from shore sites near the island of Kronstadt and along the Neva River in the urban area of Saint Petersburg. Most ships were running at reduced speed (10 kn), i.e., not at their optimal load. Vessels for domestic and international shipping were monitored. It was seen that the distribution of the SO2 emission factors is bi-modal, with averages of 4.6 and 18.2 gSO2 kgfuel-1 for the lower and the higher mode, respectively. The emission factors show compliance with the 1% fuel sulfur content Sulfur Emission Control Areas (SECA) limit for 90% of the vessels in 2011 and 97% in 2012. The distribution of the NOx emission factor is mono-modal, with an average of 58 gNOx kgfuel-1. The corresponding emission related to the generated power yields an average of 12.1 gNOx kWh-1. The distribution of the emission factors for particulate number shows that nearly 90% of all particles in the 5.6 nm to 10 μm size range were below 70 nm in diameter. The distribution of the corresponding emission factors for the mass indicates two separated main modes, one for particles between 30 and 300 nm and the other for above 2 μm. The average particle emission factors were found to be in the range from 0.7 to 2.7 × 1016 particles kgfuel-1 and 0.2 to 3.4 gPM kgfuel-1, respectively. The NOx and particulate emissions are comparable with other studies. The measured emission factors were compared, for individual ships, to modeled ones using the Ship Traffic Emission Assessment Model (STEAM) of the Finnish Meteorological Institute. A reasonably good agreement for gaseous sulfur and nitrogen emissions can be seen for ships in

  15. Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

    NASA Astrophysics Data System (ADS)

    Thornhill, D. A.; Williams, A. E.; Onasch, T. B.; Wood, E.; Herndon, S. C.; Kolb, C. E.; Knighton, W. B.; Zavala, M.; Molina, L. T.; Marr, L. C.

    2009-12-01

    The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA) using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF) receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML) measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO), nitrogen oxides (NOx), benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM2.5), and black carbon (BC). These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NOx and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are responsible for 97% of mobile source emissions of CO, 22% of NOx, 95-97% of aromatics, 72-85% of carbonyls, 74% of ammonia, negligible amounts of particle number, 26% of PM2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NOx and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction. Nevertheless, the fuel-based inventory suggests that mobile source emissions of CO and NOx are overstated in the official inventory while

  16. Emission factors of SO2, NOx and particles from ships in Neva Bay from ground-based and helicopter-borne measurements and AIS-based modeling

    NASA Astrophysics Data System (ADS)

    Beecken, J.; Mellqvist, J.; Salo, K.; Ekholm, J.; Jalkanen, J.-P.; Johansson, L.; Litvinenko, V.; Volodin, K.; Frank-Kamenetsky, D. A.

    2014-10-01

    Emission factors of SO2, NOx and size distributed particle numbers were measured for approximately 300 different ships in the Gulf of Finland and Neva Bay area during two campaigns in August/September 2011 and June/July 2012. The measurements were carried out from a harbor vessel and from an MI-8 helicopter downwind of passing ships. Other measurements were carried out from shore sites near the island of Kronstadt and along the river Neva in the city area of Saint Petersburg. Most ships were running at reduced speed (10 knots), i.e. not at their optimal load. Vessels for domestic and international shipping were monitored. It was seen that the distribution of the SO2 emission factors is bi-modal with averages of 4.6 gSO2 kgfuel-1 and 18.2 gSO2 kgfuel-1 for the lower and the higher mode, respectively. The emission factors show compliance with the 1% fuel sulfur content SECA limit for 90% of the vessels in 2011 and 97% in 2012. The distribution of the NOx emission factor is mono-modal with an average of 58 gNOx kgfuel-1. The corresponding emission related to the generated power yields an average of 12.1 gNOx kWh-1. The distribution of the emission factors for particulate number shows that nearly 90% of all particles in the 5.6 nm to 10 μm size range were below 70 nm in diameter. The distribution of the corresponding emission factors for the mass indicates two separated main modes, one for particles between 30 and 300 nm the other above 2 μm. The average particle emission factors were found to be in the range from 0.7 to 2.7 × 1016 particles kgfuel-1 and 0.2 to 3.4 gPM kgfuel-1, respectively. The NOx and particulate emissions are comparable with other studies. The measured emission factors were compared, for individual ships, to modeled ones using the Ship Traffic Emission Assessment Model (STEAM) of the Finnish Meteorological Institute. A reasonably good agreement for gaseous sulfur and nitrogen emissions can be seen for ships in international traffic, but

  17. Measurements of VOC/SVOC emission factors from burning incenses in an environmental test chamber: influence of temperature, relative humidity, and air exchange rate.

    PubMed

    Manoukian, A; Buiron, D; Temime-Roussel, B; Wortham, H; Quivet, E

    2016-04-01

    This study investigates the influence of three environmental indoor parameters (i.e., temperature, relative humidity, and air exchange rate) on the emission of 13 volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) during incense burning. Experiments have been carried out using an environmental test chamber. Statistical results from a classical two-level full factorial design highlight the predominant effect of ventilation on emission factors. The higher the ventilation, the higher the emission factor. Moreover, thanks to these results, an estimation of the concentration range for the compounds under study can be calculated and allows a quick look of indoor pollution induced by incense combustion. Carcinogenic substances (i.e., benzene, benzo(a)pyrene, and formaldehyde) produced from the incense combustion would be predicted in typical living indoors conditions to reach instantaneous concentration levels close to or higher than air quality exposure threshold values.

  18. Residual effects of fertilization history increase nitrous oxide emissions from zero-N controls:Implications for estimating fertilizer-induced emission factors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural N fertilization is the dominant driver of increasing atmospheric nitrous oxide (N2O) concentrations over the past half century, yet there is considerable uncertainty in estimates of N2O emissions from agriculture. Such estimates are typically based on the amount of N applied and a ferti...

  19. Quantification of vehicle fleet PM10 particulate matter emission factors from exhaust and non-exhaust sources using tunnel measurement techniques.

    PubMed

    Lawrence, Samantha; Sokhi, Ranjeet; Ravindra, Khaiwal

    2016-03-01

    Road tunnels act like large laboratories; they provide an excellent environment to quantify atmospheric particles emission factors from exhaust and non-exhaust sources due to their known boundary conditions. Current work compares the High Volume, Dichotomous Stacked Filter Unit and Partisol Air Sampler for coarse, PM10 and PM2.5 particle concentration measurement and found that they do not differ significantly (p = 95%). PM2.5 fraction contributes 66% of PM10 proportions and significantly influenced by traffic (turbulence) and meteorological conditions. Mass emission factors for PM10 varies from 21.3 ± 1.9 to 28.8 ± 3.4 mg/vkm and composed of Motorcycle (0.0003-0.001 mg/vkm), Cars (26.1-33.4 mg/vkm), LDVs (2.4-3.0 mg/vkm), HDVs (2.2-2.8 mg/vkm) and Buses (0.1 mg/vkm). Based on Lawrence et al. (2013), source apportionment modelling, the PM10 emission of brake wear (3.8-4.4 mg/vkm), petrol exhaust (3.9-4.5 mg/vkm), diesel exhaust (7.2-8.3 mg/vkm), re-suspension (9-10.4 mg/vkm), road surface wear (3.9-4.5 mg/vkm), and unexplained (7.2 mg/vkm) were also calculated. The current study determined that the combined non-exhaust fleet PM10 emission factor (16.7-19.3 mg/vkm) are higher than the combined exhaust emission factor (11.1-12.8 mg/vkm). Thus, highlight the significance of non-exhaust emissions and the need for legislation and abatement strategies to reduce their contributions to ambient PM concentrations. PMID:26844787

  20. Quantification of vehicle fleet PM10 particulate matter emission factors from exhaust and non-exhaust sources using tunnel measurement techniques.

    PubMed

    Lawrence, Samantha; Sokhi, Ranjeet; Ravindra, Khaiwal

    2016-03-01

    Road tunnels act like large laboratories; they provide an excellent environment to quantify atmospheric particles emission factors from exhaust and non-exhaust sources due to their known boundary conditions. Current work compares the High Volume, Dichotomous Stacked Filter Unit and Partisol Air Sampler for coarse, PM10 and PM2.5 particle concentration measurement and found that they do not differ significantly (p = 95%). PM2.5 fraction contributes 66% of PM10 proportions and significantly influenced by traffic (turbulence) and meteorological conditions. Mass emission factors for PM10 varies from 21.3 ± 1.9 to 28.8 ± 3.4 mg/vkm and composed of Motorcycle (0.0003-0.001 mg/vkm), Cars (26.1-33.4 mg/vkm), LDVs (2.4-3.0 mg/vkm), HDVs (2.2-2.8 mg/vkm) and Buses (0.1 mg/vkm). Based on Lawrence et al. (2013), source apportionment modelling, the PM10 emission of brake wear (3.8-4.4 mg/vkm), petrol exhaust (3.9-4.5 mg/vkm), diesel exhaust (7.2-8.3 mg/vkm), re-suspension (9-10.4 mg/vkm), road surface wear (3.9-4.5 mg/vkm), and unexplained (7.2 mg/vkm) were also calculated. The current study determined that the combined non-exhaust fleet PM10 emission factor (16.7-19.3 mg/vkm) are higher than the combined exhaust emission factor (11.1-12.8 mg/vkm). Thus, highlight the significance of non-exhaust emissions and the need for legislation and abatement strategies to reduce their contributions to ambient PM concentrations.

  1. 40 CFR Table I-5 to Subpart I of... - Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for MEMS Manufacturing I Table I-5...) and By-Product Formation Rates (Bijk) for MEMS Manufacturing ER13NO13.021...

  2. 40 CFR Table I-15 to Subpart I of... - Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Default Emission Factors (1-Uij) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for MEMS Manufacturing for Use With...) for Gas Utilization Rates (Uij) and By-Product Formation Rates (Bijk) for MEMS Manufacturing for...

  3. 40 CFR Table 1 to Subpart Wwww of... - Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal Casting Process Streams 1 Table 1 to Subpart WWWW of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  4. 40 CFR Table 1 to Subpart Wwww of... - Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 12 2011-07-01 2009-07-01 true Equations To Calculate Organic HAP Emissions Factors for Specific Open Molding and Centrifugal Casting Process Streams 1 Table 1 to Subpart... Specific Open Molding and Centrifugal Casting Process Streams ER25AU05.020 ER25AU05.021...

  5. On-road measurements of NMVOCs and NOx: Determination of light-duty vehicles emission factors from tunnel studies in Brussels city center

    NASA Astrophysics Data System (ADS)

    Ait-Helal, W.; Beeldens, A.; Boonen, E.; Borbon, A.; Boréave, A.; Cazaunau, M.; Chen, H.; Daële, V.; Dupart, Y.; Gaimoz, C.; Gallus, M.; George, C.; Grand, N.; Grosselin, B.; Herrmann, H.; Ifang, S.; Kurtenbach, R.; Maille, M.; Marjanovic, I.; Mellouki, A.; Miet, K.; Mothes, F.; Poulain, L.; Rabe, R.; Zapf, P.; Kleffmann, J.; Doussin, J.-F.

    2015-12-01

    Emission factors (EFs) of pollutants emitted by light-duty vehicles (LDV) were investigated in the Leopold II tunnel in Brussels city center (Belgium), in September 2011 and in January 2013, respectively. Two sampling sites were housing the instruments for the measurements of a large range of air pollutants, including non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NOx) and carbon dioxide (CO2). The NMVOCs and NOx traffic EFs for LDV were determined from their correlation with CO2 using a single point analysis method. The emission factor of NOx is (544 ± 199) mg vehicle-1 km-1; NMVOCs emission factors vary from (0.26 ± 0.09) mg vehicle-1 km-1 for cis-but-2-ene to (8.11 ± 2.71) mg vehicle-1 km-1 for toluene. Good agreement is observed between the EFs determined in the Leopold II tunnel and the most recent EFs determined in another European roadway tunnel in 2004, with only a slight decrease of the EFs during the last decade. An historical perspective is provided and the observed trend in the NMVOCs emission factors reflect changes in the car fleet composition, the fuels and/or the engine technology that have occurred within the last three decades in Europe.

  6. Characterizing fluorescent dissolved organic matter in a membrane bioreactor via excitation-emission matrix combined with parallel factor analysis.

    PubMed

    Maqbool, Tahir; Quang, Viet Ly; Cho, Jinwoo; Hur, Jin

    2016-06-01

    In this study, we successfully tracked the dynamic changes in different constitutes of bound extracellular polymeric substances (bEPS), soluble microbial products (SMP), and permeate during the operation of bench scale membrane bioreactors (MBRs) via fluorescence excitation-emission matrix (EEM) combined with parallel factor analysis (PARAFAC). Three fluorescent groups were identified, including two protein-like (tryptophan-like C1 and tyrosine-like C2) and one microbial humic-like components (C3). In bEPS, protein-like components were consistently more dominant than C3 during the MBR operation, while their relative abundance in SMP depended on aeration intensities. C1 of bEPS exhibited a linear correlation (R(2)=0.738; p<0.01) with bEPS amounts in sludge, and C2 was closely related to the stability of sludge. The protein-like components were more greatly responsible for membrane fouling. Our study suggests that EEM-PARAFAC can be a promising monitoring tool to provide further insight into process evaluation and membrane fouling during MBR operation.

  7. Revised (Mixed-Effects) Estimation for Forest Burning Emissions of Gases and Smoke, Fire/Emission Factor Typology, and Potential Remote Sensing Classification of Types for Ozone and Black-Carbon Simulation

    NASA Technical Reports Server (NTRS)

    Chatfield, Robert B.; Segal Rozenhaimer, M.

    2014-01-01

    We summarize recent progress (a) in correcting biomass burning emissions factors deduced from airborne sampling of forest fire plumes, (b) in understanding the variability in reactivity of the fresh plumes sampled in ARCTAS (2008), DC3 (2012), and SEAC4RS (2013) airborne missions, and (c) in a consequent search for remotely sensed quantities that help classify forest-fire plumes. Particle properties, chemical speciation, and smoke radiative properties are related and mutually informative, as pictures below suggest (slopes of lines of same color are similar). (a) Mixed-effects (random-effects) statistical modeling provides estimates of both emission factors and a reasonable description of carbon-burned simultaneously. Different fire plumes will have very different contributions to volatile organic carbon reactivity; this may help explain differences of free NOx(both gas- and particle-phase), and also of ozone production, that have been noted for forest-fire plumes in California. Our evaluations check or correct emission factors based on sequential measurements (e.g., the Normalized Ratio Enhancement and similar methods). We stress the dangers of methods relying on emission-ratios to CO. (b) This work confirms and extends many reports of great situational variability in emissions factors. VOCs vary in OH reactivity and NOx-binding. Reasons for variability are not only fuel composition, fuel condition, etc., but are confused somewhat by rapid transformation and mixing of emissions. We use "unmixing" (distinct from mixed-effects) statistics and compare briefly to approaches like neural nets. We focus on one particularly intense fire the notorious Yosemite Rim Fire of 2013. In some samples, NOx activity was not so suppressed by binding into nitrates as in other fires. While our fire-typing is evolving and subject to debate, the carbon-burned delta(CO2+CO) estimates that arise from mixed effects models, free of confusion by background-CO2 variation, should provide a

  8. Revised (Mixed-Effects) Estimation for Forest Burning Emissions of Gases and Smoke, Fire/Emission Factor Typologies, and Potential Remote Sensing Classification of Types for Use in Ozone and Absorbing-Carbon Simulation

    NASA Astrophysics Data System (ADS)

    Chatfield, R. B.; Segal-Rosenhaimer, M.

    2014-12-01

    We summarize recent progress (a) in correcting biomass burning emissions factors deduced from airborne sampling of forest fire plumes, (b) in understanding the variability in reactivity of the fresh plumes sampled in ARCTAS (2008), DC3 (2012), and SEAC4RS (2013) airborne missions, and (c) in a consequent search for remotely sensed quantities that help classify forest-fire plumes. Particle properties, chemical speciation, and smoke radiative properties are related and mutually informative, as pictures below suggest (slopes of lines of same color are similar). (a) Mixed-effects (random-effects) statistical modeling provides estimates of both emission factors and a reasonable description of carbon-burned simultaneously. Different fire plumes will have very different contributions to volatile organic carbon reactivity; this may help explain differences of free NOx(both gas- and particle-phase), and also of ozone production, that have been noted for forest-fire plumes in California. Our evalualations check or correct emission factors based on sequential measurements (e.g., the Normalized Ratio Enhancement and similar methods). We stress the dangers of methods relying on emission-ratios to CO. (b) This work confirms and extends many reports of great situational variability in emissions factors. VOCs vary in OH reactivity and NOx-binding. Reasons for variability are not only fuel composition, fuel condition, etc, but are confused somewhat by rapid transformation and mixing of emissions. We use "unmixing" (distinct from mixed-effects) statistics and compare briefly to approaches like neural nets. We focus on one particularly intense fire the notorious Yosemite Rim Fire of 2013. In some samples, NOx activity was not so surpressed by binding into nitrates as in other fires. While our fire-typing is evolving and subject to debate, the carbon-burned Δ(CO2+CO) estimates that arise from mixed effects models, free of confusion by background-CO2 variation, should provide a solid

  9. Application of positive matrix factorization to on-road measurements for source apportionment of diesel- and gasoline-powered vehicle emissions in Mexico City

    NASA Astrophysics Data System (ADS)

    Thornhill, D. A.; Williams, A. E.; Onasch, T. B.; Wood, E.; Herndon, S. C.; Kolb, C. E.; Knighton, W. B.; Zavala, M.; Molina, L. T.; Marr, L. C.

    2010-04-01

    The goal of this research is to quantify diesel- and gasoline-powered motor vehicle emissions within the Mexico City Metropolitan Area (MCMA) using on-road measurements captured by a mobile laboratory combined with positive matrix factorization (PMF) receptor modeling. During the MCMA-2006 ground-based component of the MILAGRO field campaign, the Aerodyne Mobile Laboratory (AML) measured many gaseous and particulate pollutants, including carbon dioxide, carbon monoxide (CO), nitrogen oxides (NOx), benzene, toluene, alkylated aromatics, formaldehyde, acetaldehyde, acetone, ammonia, particle number, fine particulate mass (PM2.5), and black carbon (BC). These serve as inputs to the receptor model, which is able to resolve three factors corresponding to gasoline engine exhaust, diesel engine exhaust, and the urban background. Using the source profiles, we calculate fuel-based emission factors for each type of exhaust. The MCMA's gasoline-powered vehicles are considerably dirtier, on average, than those in the US with respect to CO and aldehydes. Its diesel-powered vehicles have similar emission factors of NOx and higher emission factors of aldehydes, particle number, and BC. In the fleet sampled during AML driving, gasoline-powered vehicles are found to be responsible for 97% of total vehicular emissions of CO, 22% of NOx, 95-97% of each aromatic species, 72-85% of each carbonyl species, 74% of ammonia, negligible amounts of particle number, 26% of PM2.5, and 2% of BC; diesel-powered vehicles account for the balance. Because the mobile lab spent 17% of its time waiting at stoplights, the results may overemphasize idling conditions, possibly resulting in an underestimate of NOx and overestimate of CO emissions. On the other hand, estimates of the inventory that do not correctly account for emissions during idling are likely to produce bias in the opposite direction.The resulting fuel-based estimates of emissions are lower than in the official inventory for CO and NOx

  10. Methane emissions from rice fields: The effects of climatic and agricultural factors. Final report, March 1, 1994--April 30, 1997

    SciTech Connect

    Khalil, M.A.K.; Rasmussen, R.A.

    1997-10-01

    The work reported was performed for the purpose of refining estimates of methane emissions from rice fields. Research performed included methane flux measurements, evaluation of variables affecting emissions, compilation of a data base, and continental background measurements in China. The key findings are briefly described in this report. Total methane emissions, seasonal patterns, and spatial variability were measured for a 7-year periods. Temperature was found to be the most important variable studies affecting methane emissions. The data archives for the research are included in the report. 5 refs., 6 figs.

  11. Influence of environmental factors and air composition on the emission of {alpha}-pinene from Quercus ilex leaves

    SciTech Connect

    Loreto, F.; Tricoli, D.; Ciccioli, P.

    1996-01-01

    We studied the emission of {alpha}-pinene from Quercus ilex leaves. Only the abaxial side of the hypostomatous Q. ilex leaf emits {alpha}-pinene. Light induced photosynthesis and {alpha}-pinene emission. However, the response of photosynthesis to dark-to-light transitions was faster than that of {alpha}-pinene, suggesting that ATP controls the emission. The emission was higher at 30 than at 20{degrees}C, whereas photosynthesis did not change. Therefore, the relationship between photosynthesis and {alpha}-pinene emission does not always hold. When CO{sub 2} was removed from the air, transpiration was stimulated and transpiration was reduced, but {alpha}-pinene emission was unaffected. Therefore, the emission depends on the availability of photosynthetic carbon, is not saturated at ambient CO{sub 2}, and is not dependent on stomatal opening. The pattern of {alpha}-pinene emission from Q. ilex is different from that of plants having specialized structures for storage and emission of terpenes. We suggest that {alpha}-pinene emitted by Q. ilex leaves is synthesized in the chloroplasts and shares the same biochemical pathway with isoprene emitted by isoprene-emitting oak species. 28 refs., 8 figs., 1 tab.

  12. Real-world emission factors for antimony and other brake wear related trace elements: size-segregated values for light and heavy duty vehicles.

    PubMed

    Bukowiecki, Nicolas; Lienemann, Peter; Hill, Matthias; Figi, Renato; Richard, Agnes; Furger, Markus; Rickers, Karen; Falkenberg, Gerald; Zhao, Yongjing; Cliff, Steven S; Prevot, Andre S H; Baltensperger, Urs; Buchmann, Brigitte; Gehrig, Robert

    2009-11-01

    Hourly trace element measurements were performed in an urban street canyon and next to an interurban freeway in Switzerland during more than one month each, deploying a rotating drum impactor (RDI) and subsequent sample analysis by synchrotron radiation X-ray fluorescence spectrometry (SR-XRF). Antimony and other brake wear associated elements were detected in three particle size ranges (2.5-10, 1-2.5, and 0.1-1 microm). The hourly measurements revealed that the effect of resuspended road dust has to be taken into account for the calculation of vehicle emission factors. Individual values for light and heavy duty vehicles were obtained for stop-and-go traffic in the urban street canyon. Mass based brake wear emissions were predominantly found in the coarse particle fraction. For antimony, determined emission factors were 11 +/- 7 and 86 +/- 42 microg km(-1) vehicle(-1) for light and heavy duty vehicles, respectively. Antimony emissions along the interurban freeway with free-flowing traffic were significantly lower. Relative patterns for brake wear related elements were very similar for both considered locations. Beside vehicle type specific brake wear emissions, road dust resuspension was found to be a dominant contributor of antimony in the street canyon.

  13. Comparison of models for estimating methane emission factor for enteric fermentation of growing-finishing Hanwoo steers.

    PubMed

    Jo, Namchul; Kim, Jongnam; Seo, Seongwon

    2016-01-01

    The methodology provided by the Intergovernmental Panel on Climate Change (IPCC) guidelines is widely used for estimating enteric methane (CH4) production by cattle. No attempt other than the default values in the IPCC Tier 1 has been made for estimating CH4 emission from Hanwoo, a dominant beef species in Korea raised in a unique feeding system. The objective of this study was to compare models for estimating the CH4 emission factor (MEF; kg CH4/head/year) for enteric fermentation in Hanwoo steers. The MEF was estimated based on Korea- and Hanwoo-specific data obtained from the literature using several models. The models include the IPCC Tier 1 (T1), the IPCC Tier 2 method (T2), the IPCC Tier 2 methodology with actual dry matter intake (T2DMI), and the Japanese Tier 3 method (JT3). The JT3 was included due to the similarity in the beef cattle production system between the two countries. Estimated MEF using T2 were 43.4, 33.9, and 36.2 kg CH4/head/year for the growing, finishing, and overall period, respectively. The overall MEF estimated using T2 was 23 % lower than the estimate by T1 (47.0 kg CH4/head/year). There were significant differences in the estimated MEF for enteric fermentation of Hanwoo steers among the methods (P < 0.05). The overall MEF estimated by JT3 was 69.1 kg CH4/head/year, which was significantly higher than the estimates by T2 (36.2 kg) and T2DMI (33.5 kg). The JT3 estimated the highest values in all periods possibly due to overestimation of the conversion ratio of feed energy to CH4. No significant difference was found in the overall MEF of Hanwoo steers between T2 and T2DMI. However, T2DMI estimated 8 % higher and 14 % lower MEF than T2 for the growing and finishing period, respectively, mainly because the T2 significantly over-predicts the gross energy intake of Hanwoo steers at the high level of intake. The IPCC default methods have limitations in their use for a feeding systems in non-western countries, and thus development of

  14. Emission Factors for CO2, CO, CH4, and C2 - C4 Hydrocarbons from the 2011 Great Dismal Swamp, Virginia Fire

    NASA Astrophysics Data System (ADS)

    Baker, S.; Soja, A. J.; Richardson, M. J.

    2012-12-01

    With a warming climate, increased dry conditions and drought periods are likely to result in higher fire activity in the wetlands of the eastern and southeastern US. Fires in this fuel type can smolder for months producing significant carbon release and major impacts on air quality. While a comprehensive set of emission factors has been established for most US fuel types, a less complete set is available for emissions where deep layers of organic matter can consume and smolder for days, weeks and months. Lightning started the Lateral West fire in the Great Dismal Swamp National Wildlife Refuge, Virginia on August 4, and it burned slowly through drought-stressed hardwood forest and dry peat soil. The fire produced dense plumes of smoke that mostly dispersed over the Atlantic Ocean, but also affected air quality as far away as Washington, D.C. Fire emissions were sampled August 26, 2011. The fire had burned 6,358 acres. and was smoldering along in the peat, with some brush still igniting. The average emission factors (EF) we measured from the sampling were 1441 g/kg CO2, 192 g/kg CO; and 16.5 g/kg CH4.. Modified combustion efficiency (MCE) was 0.83, produced by the small amount of flaming combustion mixed with smoldering combustion of the peat. The CO2 EF values are similar to those measured from smoldering duff in Alaska in 2003 (1436 g/kg), and the CO EF was lower than Alaska (244 g/kg CO), while the CH4 EF was much higher than Alaska (8.4 g/kg CH4). We will present our complete set of emission factors from the Great Dismal Swamp for CO2, CO, CH4, and C2 - C4 hydrocarbons, and contrast these results with other fuel types. Linear regressions of C1- C4 hydrocarbons vs. CO concentration will presented and compared with other emissions results.

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