40 CFR 94.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...

40 CFR 94.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...

40 CFR 94.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...

40 CFR 94.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...

40 CFR 94.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... emission control device (AECD) means any element of design which senses temperature, vessel speed, engine... means those devices, systems or elements of design which control or reduce the emission of substances.... Total Hydrocarbon Equivalent means the sum of the carbon mass contributions of non-oxygenated...

Environmental assessment of NH/sub 3/ injection for an industrial package boiler. Volume 1. Technical results. Final report, January 1983-January 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castaldini, C.; DeRosier, R.; Waterland, L.R.

1986-02-01

The report discusses emission results from comprehensive flue gas sampling of a gas- and oil-fired industrial boiler equipped with Exxon's Thermal DeNO/sub x/ Ammonia Injection Process for NO/sub x/ reduction. Comprehensive emission measurements included continuous monitoring of flue gas emissions; source assessment sampling system (SASS) tests; EPA Method 5/17 for solid and condensible particulate emissions and ammonia emissions; controlled condensation system for SO/sub 2/ and SO/sub 3/; and N/sub 2/O emission sampling. Ammonia injection at a NH/sub 3//NO molar ratio of 2.52 gave a NO/sub x/ reduction of 41% from an uncontrolled level of 234 ppm to a controlled levelmore » of 137 ppm. NH/sub 3/ emissions increased from 11 ppm for the baseline to an average of 430 ppm for ammonia injection. Nitrous oxide, N/sub 2/O was reduced 68% from a 50 ppm baseline level to a 17 ppm controlled level. Total particulate emissions increased by an order of magnitude from a baseline of 17.7 ng/J to a controlled level of 182 ng/J. The increase is in part attributed to formation of ammonia sulfate and bisulfate from residual ammonia and SO/sub x/. Total organic emissions were at a moderate level and showed a relative concentration in the nonvolatile category. Organic emissions of CO and trace inorganic elements were not significantly affected by ammonia injection.« less

Atmospheric nitrogen deposition in the Yangtze River basin: Spatial pattern and source attribution.

PubMed

Xu, Wen; Zhao, Yuanhong; Liu, Xuejun; Dore, Anthony J; Zhang, Lin; Liu, Lei; Cheng, Miaomiao

2018-01-01

The Yangtze River basin is one of the world's hotspots for nitrogen (N) deposition and likely plays an important role in China's riverine N output. Here we constructed a basin-scale total dissolved inorganic N (DIN) deposition (bulk plus dry) pattern based on published data at 100 observational sites between 2000 and 2014, and assessed the relative contributions of different reactive N (N r ) emission sectors to total DIN deposition using the GEOS-Chem model. Our results show a significant spatial variation in total DIN deposition across the Yangtze River basin (33.2 kg N ha -1 yr -1 on average), with the highest fluxes occurring mainly in the central basin (e.g., Sichuan, Hubei and Hunan provinces, and Chongqing municipality). This indicates that controlling N deposition should build on mitigation strategies according to local conditions, namely, implementation of stricter control of N r emissions in N deposition hotspots but moderate control in the areas with low N deposition levels. Total DIN deposition in approximately 82% of the basin area exceeded the critical load of N deposition for semi-natural ecosystems along the basin. On the basin scale, the dominant source of DIN deposition is fertilizer use (40%) relative to livestock (11%), industry (13%), power plant (9%), transportation (9%), and others (18%, which is the sum of contributions from human waste, residential activities, soil, lighting and biomass burning), suggesting that reducing NH 3 emissions from improper fertilizer (including chemical and organic fertilizer) application should be a priority in curbing N deposition. This, together with distinct spatial variations in emission sector contributions to total DIN deposition also suggest that, in addition to fertilizer, major emission sectors in different regions of the basin should be considered when developing synergistic control measures. Copyright © 2017. Published by Elsevier Ltd.

40 CFR 86.427-78 - Emission tests.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Emission tests. 86.427-78 Section 86... Later New Motorcycles, General Provisions § 86.427-78 Emission tests. (a)(1) Each test vehicle shall be driven with all emission control systems installed and operating for the following total test distances...

40 CFR 86.427-78 - Emission tests.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Emission tests. 86.427-78 Section 86... Later New Motorcycles, General Provisions § 86.427-78 Emission tests. (a)(1) Each test vehicle shall be driven with all emission control systems installed and operating for the following total test distances...

40 CFR 86.427-78 - Emission tests.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Emission tests. 86.427-78 Section 86... Later New Motorcycles, General Provisions § 86.427-78 Emission tests. (a)(1) Each test vehicle shall be driven with all emission control systems installed and operating for the following total test distances...

CONTROL TECHNOLOGY OVERVIEW REPORT: CFC (CHLOROFLUOROCARBON) EMISSIONS FROM RIGID FOAM MANUFACTURING

EPA Science Inventory

The report estimates total chlorofluorocarbon (CFC) emissions from the various rigid foam manufacturing processes and from the foam products themselves, and examines potential methods for reducing these emissions. Options studied include replacement of CFC-blown products with alt...

Reactivity-based industrial volatile organic compounds emission inventory and its implications for ozone control strategies in China

NASA Astrophysics Data System (ADS)

Liang, Xiaoming; Chen, Xiaofang; Zhang, Jiani; Shi, Tianli; Sun, Xibo; Fan, Liya; Wang, Liming; Ye, Daiqi

2017-08-01

Increasingly serious ozone (O3) pollution, along with decreasing NOx emission, is creating a big challenge in the control of volatile organic compounds (VOCs) in China. More efficient and effective measures are assuredly needed for controlling VOCs. In this study, a reactivity-based industrial VOCs emission inventory was established in China based on the concept of ozone formation potential (OFP). Key VOCs species, major VOCs sources, and dominant regions with high reactivity were identified. Our results show that the top 15 OFP-based species, including m/p-xylene, toluene, propene, o-xylene, and ethyl benzene, contribute 69% of the total OFP but only 30% of the total emission. The architectural decoration industry, oil refinery industry, storage and transport, and seven other sources constituted the top 10 OFP subsectors, together contributing a total of 85%. The provincial and spatial characteristics of OFP are generally consistent with those of mass-based inventory. The implications for O3 control strategies in China are discussed. We propose a reactivity-based national definition of VOCs and low-reactive substitution strategies, combined with evaluations of health risks. Priority should be given to the top 15 or more species with high reactivity through their major emission sources. Reactivity-based policies should be flexibly applied for O3 mitigation based on the sensitivity of O3 formation conditions.

An AIS-based high-resolution ship emission inventory and its uncertainty in Pearl River Delta region, China.

PubMed

Li, Cheng; Yuan, Zibing; Ou, Jiamin; Fan, Xiaoli; Ye, Siqi; Xiao, Teng; Shi, Yuqi; Huang, Zhijiong; Ng, Simon K W; Zhong, Zhuangmin; Zheng, Junyu

2016-12-15

Ship emissions contribute significantly to air pollution and impose health risks to residents along the coastal area. By using the refined data from the Automatic Identification System (AIS), this study developed a highly resolved ship emission inventory for the Pearl River Delta (PRD) region, China, home to three of ten busiest ports in the world. The region-wide SO 2 , NO X , CO, PM 10 , PM 2.5 , and VOC emissions in 2013 were estimated to be 61,484, 103,717, 10,599, 7155, 6605, and 4195t, respectively. Ocean going vessels were the largest contributors of the total emissions, followed by coastal vessels and river vessels. In terms of ship type, container ship was the leading contributor, followed by conventional cargo ship, dry bulk carrier, fishing ship, and oil tanker. These five ship types accounted for >90% of total emissions. The spatial distributions of emissions revealed that the key emission hot spots all concentrated within the newly proposed emission control area (ECA) and ship emissions within ECA covered >80% of total ship emissions in the PRD, highlighting the importance of ECA in emissions reduction in the PRD. The uncertainties of emission estimates of pollutants were quantified, with lower bounds of -24.5% to -21.2% and upper bounds of 28.6% to 33.3% at 95% confidence intervals. The lower uncertainties in this study highlighted the powerfulness of AIS data in improving ship emission estimates. The AIS-based bottom-up methodology can be used for developing and upgrading ship emission inventory and formulating effective control measures on ship emissions in other port regions wherever possible. Copyright © 2016 Elsevier B.V. All rights reserved.

Municipal solid waste management planning considering greenhouse gas emission trading under fuzzy environment.

PubMed

Zhang, Xiaodong; Huang, Gordon

2014-03-15

Waste management activities can release greenhouse gases (GHGs) to the atmosphere, intensifying global climate change. Mitigation of the associated GHG emissions is vital and should be considered within integrated municipal solid waste (MSW) management planning. In this study, a fuzzy possibilistic integer programming (FPIM) model has been developed for waste management facility expansion and waste flow allocation planning with consideration of GHG emission trading in an MSW management system. It can address the interrelationships between MSW management planning and GHG emission control. The scenario of total system GHG emission control is analyzed for reflecting the feature that GHG emission credits may be tradable. An interactive solution algorithm is used to solve the FPIM model based on the uncertainty-averse preferences of decision makers in terms of p-necessity level, which represents the certainty degree of the imprecise objective. The FPIM model has been applied to a hypothetical MSW planning problem, where optimal decision schemes for facility expansion and waste flow allocation have been achieved with consideration of GHG emission control. The results indicate that GHG emission credit trading can decrease total system cost through re-allocation of GHG emission credits within the entire MSW management system. This will be helpful for decision makers to effectively determine the allowable GHG emission permits in practices. Copyright © 2014 Elsevier Ltd. All rights reserved.

Historic and future trends of vehicle emissions in Beijing, 1998-2020: A policy assessment for the most stringent vehicle emission control program in China

NASA Astrophysics Data System (ADS)

Zhang, Shaojun; Wu, Ye; Wu, Xiaomeng; Li, Mengliang; Ge, Yunshan; Liang, Bin; Xu, Yueyun; Zhou, Yu; Liu, Huan; Fu, Lixin; Hao, Jiming

2014-06-01

As a pioneer in controlling vehicle emissions within China, Beijing released the Clean Air Action Plan 2013-2017 document in August 2013 to improve its urban air quality. It has put forward this plan containing the most stringent emission control policies and strategies to be adopted for on-road vehicles of Beijing. This paper estimates the historic and future trends and uncertainties in vehicle emissions of Beijing from 1998 to 2020 by applying a new emission factor model for the Beijing vehicle fleet (EMBEV). Our updated results show that total emissions of CO, THC, NOx and PM2.5 from the Beijing vehicle fleet are 507 (395-819) kt, 59.1 (41.2-90.5) kt, 74.7 (54.9-103.9) kt and 2.69 (1.91-4.17) kt, respectively, at a 95% confidence level. This represents significant reductions of 58%, 59%, 31% and 62%, respectively, relative to the total vehicle emissions in 1998. The past trends clearly posed a challenge to NOx emission mitigation for the Beijing vehicle fleet, especially in light of those increasing NOx emissions from heavy-duty diesel vehicles (HDDVs) which have partly offset the reduction benefit from light-duty gasoline vehicles (LDGVs). Because of recently announced vehicle emission controls to be adopted in Beijing, including tighter emissions standards, limitations on vehicle growth by more stringent license control, promotion of alternative fuel technologies (e.g., natural gas) and the scrappage of older vehicles, estimated vehicle emissions in Beijing will continue to be mitigated by 74% of CO, 68% of THC, 56% of NOx and 72% of PM2.5 in 2020 compared to 2010 levels. Considering that many of the megacities in China are facing tremendous pressures to mitigate emissions from on-road vehicles, our assessment will provide a timely case study of significance for policy-makers in China.

40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

Code of Federal Regulations, 2011 CFR

2011-07-01

... National Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63... percent reduction may be measured as total epoxide, total organic HAP, or as TOC minus methane and ethane... TOC (minus methane and ethane) concentrations in all process vent streams and primary and secondary...

40 CFR 63.1426 - Process vent requirements for determining organic HAP concentration, control efficiency, and...

Code of Federal Regulations, 2012 CFR

2012-07-01

... National Emission Standards for Hazardous Air Pollutant Emissions for Polyether Polyols Production § 63... percent reduction may be measured as total epoxide, total organic HAP, or as TOC minus methane and ethane... TOC (minus methane and ethane) concentrations in all process vent streams and primary and secondary...

Generation of methane from paddy fields and cattle in India, and its reduction at source

NASA Astrophysics Data System (ADS)

Bandyopadhyay, T. K.; Goyal, P.; Singh, M. P.

Methane (CH4) is a saturated organic gas. About 500 Tg yr -1 methane is generated globally. It is evident that 70% of the total emission have anthropogenic sources. The paddy fields contribute a significant portion of the total methane generated. About 20% of the total methane is generated from the paddy fields. In India, methane efflux rate is negative to 49 mg m -2 hr -1. The mean CH4 flux from Indian paddy fields is calculated to be 4.0 Tgyr -1. Livestock, and in particular ruminants are one of the important sources of methane emission on a global scale. There are two sources of methane emission from live stock: (1) from digestive process of ruminants, (2) from animal wastes. The estimated value of methane emission from digestive process of ruminants in India accounts for 6.47 Tgyr -1, and animal wastes accounts for 1.60 Tgyr -1. Total generation of methane from animals in India is about 8.0 Tg yr -1 . In paddy fields the key of controlling methane emission lies in the control of irrigation water. The methane emission can be decreased drastically if the field is under dry conditions for a few days at the end of tillering. In the case of livestock, reduction of methane emission can be done by (1) increasing the intake of the animal, (2) modifying the composition of the diet, (3) eliminating protozoa in rumen, (4) improving fibre digestion efficiency and (5) inhibiting activity of methanogenic bacteria.

40 CFR 86.1816-08 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... hydrocarbons shall mean total hydrocarbon equivalents and references to non-methane hydrocarbons shall mean non... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty...

40 CFR 86.1816-08 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... hydrocarbons shall mean total hydrocarbon equivalents and references to non-methane hydrocarbons shall mean non... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty...

40 CFR 86.1816-08 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... hydrocarbons shall mean total hydrocarbon equivalents and references to non-methane hydrocarbons shall mean non... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty...

40 CFR 86.1816-08 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... hydrocarbons shall mean total hydrocarbon equivalents and references to non-methane hydrocarbons shall mean non... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty...

Behavior or Nonmetallic Materials in Shale Oil Derived Jet Fuels and in High Aromatic and High Sulfur Petroleum Fuels

DTIC Science & Technology

1978-07-01

degrades thermal stability and forms undesirable sulfur dioxide emissions . Although the original premises for controlling total sulfur may not still...eliminate corrosive trace contamination, presence of surfactants which deactivate filter/ separators, carry-over of refinery processing materials, and...increase raw vapor emissions from ground fuel handling facilities and during refueling operations. Controlling raw vapor emissions is difficult at 3

Apparatus for Measuring Total Emissivity of Small, Low-Emissivity Samples

NASA Technical Reports Server (NTRS)

Tuttle, James; DiPirro, Michael J.

2011-01-01

An apparatus was developed for measuring total emissivity of small, lightweight, low-emissivity samples at low temperatures. The entire apparatus fits inside a small laboratory cryostat. Sample installation and removal are relatively quick, allowing for faster testing. The small chamber surrounding the sample is lined with black-painted aluminum honeycomb, which simplifies data analysis. This results in the sample viewing a very high-emissivity surface on all sides, an effect which would normally require a much larger chamber volume. The sample and chamber temperatures are individually controlled using off-the-shelf PID (proportional integral derivative) controllers, allowing flexibility in the test conditions. The chamber can be controlled at a higher temperature than the sample, allowing a direct absorptivity measurement. The lightweight sample is suspended by its heater and thermometer leads from an isothermal bar external to the chamber. The wires run out of the chamber through small holes in its corners, and the wires do not contact the chamber itself. During a steady-state measurement, the thermometer and bar are individually controlled at the same temperature, so there is zero heat flow through the wires. Thus, all of sample-temperature-control heater power is radiated to the chamber. Double-aluminized Kapton (DAK) emissivity was studied down to 10 K, which was about 25 K colder than any previously reported measurements. This verified a minimum in the emissivity at about 35 K and a rise as the temperature dropped to lower values.

Assessment of vehicle emission programs in China during 1998-2013: Achievement, challenges and implications.

PubMed

Wu, Xiaomeng; Wu, Ye; Zhang, Shaojun; Liu, Huan; Fu, Lixin; Hao, Jiming

2016-07-01

China has been embracing rapid motorization since the 1990s, and vehicles have become one of the major sources of air pollution problems. Since the late 1990s, thanks to the international experience, China has adopted comprehensive control measures to mitigate vehicle emissions. This study employs a local emission model (EMBEV) to assess China's first fifteen-year (1998-2013) efforts in controlling vehicles emissions. Our results show that China's total annual vehicle emissions in 2013 were 4.16 million tons (Mt) of HC, 27.4 Mt of CO, 7.72 Mt of NOX, and 0.37 Mt of PM2.5, respectively. Although vehicle emissions are substantially reduced relative to the without control scenarios, we still observe significantly higher emission density in East China than in developed countries with longer histories of vehicle emission control. This study further informs China's policy-makers of the prominent challenges to control vehicle emissions in the future. First, unlike other major air pollutants, total NOX emissions have rapidly increased due to a surge of diesel trucks and the postponed China IV standard nationwide. Simultaneous implementation of fuel quality improvements and vehicle-engine emission standards will be of great importance to alleviate NOX emissions for diesel fleets. Second, the enforcement of increasingly stringent standards should include strict oversight of type-approval conformity, in-use complacence and durability, which would help reduce gross emitters of PM2.5 that are considerable among in-use diesel fleets at the present. Third, this study reveals higher HC emissions than previous results and indicates evaporative emissions may have been underestimated. Considering that China's overall vehicle ownership is far from saturation, persistent efforts are required through economic tools, traffic management and emissions regulations to lower vehicle-use intensity and limit both exhaust and evaporative emissions. Furthermore, in light of the complex technology for emerging new energy vehicles, their real-world emissions need to be adequately evaluated before massive promotion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Increasing beef production could lower greenhouse gas emissions in Brazil if decoupled from deforestation

NASA Astrophysics Data System (ADS)

de Oliveira Silva, R.; Barioni, L. G.; Hall, J. A. J.; Folegatti Matsuura, M.; Zanett Albertini, T.; Fernandes, F. A.; Moran, D.

2016-05-01

Recent debate about agricultural greenhouse gas emissions mitigation highlights trade-offs inherent in the way we produce and consume food, with increasing scrutiny on emissions-intensive livestock products. Although most research has focused on mitigation through improved productivity, systemic interactions resulting from reduced beef production at the regional level are still unexplored. A detailed optimization model of beef production encompassing pasture degradation and recovery processes, animal and deforestation emissions, soil organic carbon (SOC) dynamics and upstream life-cycle inventory was developed and parameterized for the Brazilian Cerrado. Economic return was maximized considering two alternative scenarios: decoupled livestock-deforestation (DLD), assuming baseline deforestation rates controlled by effective policy; and coupled livestock-deforestation (CLD), where shifting beef demand alters deforestation rates. In DLD, reduced consumption actually leads to less productive beef systems, associated with higher emissions intensities and total emissions, whereas increased production leads to more efficient systems with boosted SOC stocks, reducing both per kilogram and total emissions. Under CLD, increased production leads to 60% higher emissions than in DLD. The results indicate the extent to which deforestation control contributes to sustainable intensification in Cerrado beef systems, and how alternative life-cycle analytical approaches result in significantly different emission estimates.

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2014 CFR

2014-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2010 CFR

2010-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2012 CFR

2012-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2011 CFR

2011-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

40 CFR Appendix A to Subpart D of... - Tables

Code of Federal Regulations, 2013 CFR

2013-07-01

... fitted for the test kW PB Total barometric pressure (average of the pre-test and post-test values) kPa...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions Pt. 91, Subpt... Term Unit AYM Final weighted emission test results g/kW-hr C3 H8 Propane CB Concentration of emission...

Assessment on the Benefits from Energy Structure Optimization and Coal-fired Emission Control in Beijing: 1998-2013

NASA Astrophysics Data System (ADS)

Zong, Y.; He, K.; Zhang, Q.; Hong, C.

2016-12-01

Coal has long been an important energy type of Beijing's energy consumption. Since 1998, to improve urban air quality, Beijing has vigorously promoted the structure optimization of energy consumption. Primary measures included the implementation of strict emission standards for coal-fired power plant boilers, subsidized replacement and after-treatment retrofit of coal-fired boilers, the mandatory application of low-sulfur coal, and the accelerated use of natural gas, imported electricity and other clean energy. This work attempts to assess the emission reduction benefits on measures of three sectors, including replacing with clean energy and application of end-of-pipe control technologies in power plants, comprehensive control on coal-fired boilers and residential heating renovation. This study employs the model of Multi-resolution Emission Inventory for China (MEIC) to quantify emission reductions from upfront measures. These control measures have effectively reduced local emissions of major air pollutants in Beijing. The total emissions of PM2.5, PM10, SO2 and NOX from power plants in Beijing are estimated to have reduced 14.5 kt, 23.7 kt, 45.0 kt and 7.6 kt from 1998 to 2013, representing reductions of 86%, 87%, 85% and 16%, respectively. Totally, 14.3 kt, 24.0 kt, 136 kt and 48.7kt of PM2.5, PM10, SO2 and NOX emissions have been mitigated due to the comprehensive control measures on coal-fired boilers from 1998 to 2013. Residential heating renovation projects by replacing coal with electricity in Beijing's conventional old house areas contribute to emission reductions of 630 t, 870 t, 2070 t and 790 t for PM2.5, PM10, SO2 and NOX, respectively.

Evaluating the effects of China's pollution controls on inter-annual trends and uncertainties of atmospheric mercury emissions

NASA Astrophysics Data System (ADS)

Zhao, Y.; Zhong, H.; Zhang, J.; Nielsen, C. P.

2015-04-01

China's anthropogenic emissions of atmospheric mercury (Hg) are effectively constrained by national air pollution control and energy efficiency policies. In this study, improved methods, based on available data from domestic field measurements, are developed to quantify the benefits of Hg abatement by various emission control measures. Those measures include increased use of (1) flue gas desulfurization (FGD) and selective catalyst reduction (SCR) systems in power generation; (2) precalciner kilns with fabric filters (FF) in cement production; (3) mechanized coking ovens with electrostatic precipitators (ESP) in iron and steel production; and (4) advanced production technologies in nonferrous metal smelting. Investigation reveals declining trends in emission factors for each of these sources, which together drive a much slower growth of total Hg emissions than the growth of China's energy consumption and economy, from 679 metric tons (t) in 2005 to 750 t in 2012. In particular, estimated emissions from the above-mentioned four source types declined 3% from 2005 to 2012, which can be attributed to expanded deployment of technologies with higher energy efficiencies and air pollutant removal rates. Emissions from other anthropogenic sources are estimated to increase by 22% during the period. The species shares of total Hg emissions have been stable in recent years, with mass fractions of around 55, 39, and 6% for gaseous elemental Hg (Hg0), reactive gaseous mercury (Hg2+), and particle-bound mercury (Hgp), respectively. The higher estimate of total Hg emissions than previous inventories is supported by limited simulation of atmospheric chemistry and transport. With improved implementation of emission controls and energy saving, a 23% reduction in annual Hg emissions from 2012 to 2030, to below 600 t, is expected at the most. While growth in Hg emissions has been gradually constrained, uncertainties quantified by Monte Carlo simulation for recent years have increased, particularly for the power sector and particular industrial sources. The uncertainty (expressed as 95% confidence intervals) of Hg emissions from coal-fired power plants, for example, increased from -48-+73% in 2005 to -50-+89% in 2012. This is attributed mainly to increased penetration of advanced manufacturing and pollutant control technologies; the unclear operational status and relatively small sample sizes of field measurements of those processes have resulted in lower but highly varied emission factors. To reduce uncertainty and further confirm the benefits of pollution control and energy polices, therefore, systematic investigation of specific Hg pollution sources is recommended. The variability of temporal trends and spatial distributions of Hg emissions needs to be better tracked during the ongoing dramatic changes in China's economy, energy use, and air pollution status.

[Effects of superphosphate addition on NH3 and greenhouse gas emissions during vegetable waste composting].

PubMed

Yang, Yan; Sun, Qin-ping; Li, Ni; Liu, Chun-sheng; Li, Ji-jin; Liu, Ben-sheng; Zou, Guo-yuan

2015-01-01

To study the effects of superphosphate (SP) on the NH, and greenhouse gas emissions, vegetable waste composting was performed for 27 days using 6 different treatments. In addition to the controls, five vegetable waste mixtures (0.77 m3 each) were treated with different amounts of the SP additive, namely, 5%, 10%, 15%, 20% and 25%. The ammonia volatilization loss and greenhouse gas emissions were measured during composting. Results indicated that the SP additive significantly decreased the ammonia volatilization and greenhouse gas emissions during vegetable waste composting. The additive reduced the total NH3 emission by 4.0% to 16.7%. The total greenhouse gas emissions (CO2-eq) of all treatments with SP additives were decreased by 10.2% to 20.8%, as compared with the controls. The NH3 emission during vegetable waste composting had the highest contribution to the greenhouse effect caused by the four different gases. The amount of NH3 (CO2-eq) from each treatment ranged from 59.90 kg . t-1 to 81.58 kg . t-1; NH3(CO2-eq) accounted for 69% to 77% of the total emissions from the four gases. Therefore, SP is a cost-effective phosphorus-based fertilizer that can be used as an additive during vegetable waste composting to reduce the NH3 and greenhouse gas emissions as well as to improve the value of compost as a fertilizer.

Assessment of methods for methyl iodide emission reduction and pest control using a simulation model

NASA Astrophysics Data System (ADS)

Luo, Lifang; Ashworth, Daniel J.; Šimunek, Jirka; Xuan, Richeng; Yates, Scott R.

2013-02-01

The increasing registration of the fumigant methyl iodide within the USA has led to more concerns about its toxicity to workers and bystanders. Emission mitigation strategies are needed to protect the public and environmental health while providing effective pest control. The effectiveness of various methods on emissions reduction and pest control was assessed using a process-based mathematical model in this study. Firstly, comparisons between the simulated and laboratory measured emission fluxes and cumulative emissions were made for methyl iodide (MeI) under four emission reduction treatments: 1) control, 2) using soil with high organic matter content (HOM), 3) being covered by virtually impermeable film (VIF), and 4) irrigating soil surface following fumigation (Irrigation). Then the model was extended to simulate a broader range of emission reduction strategies for MeI, including 5) being covered by high density polyethylene (HDPE), 6) increasing injection depth from 30 cm to 46 cm (Deep), 7) HDPE + Deep, 8) adding a reagent at soil surface (Reagent), 9) Reagent + Irrigation, and 10) Reagent + HDPE. Furthermore, the survivability of three types of soil-borne pests (citrus nematodes [Tylenchulus semipenetrans], barnyard seeds [Echinochloa crus-galli], fungi [Fusarium oxysporum]) was also estimated for each scenario. Overall, the trend of the measured emission fluxes as well as total emission were reasonably reproduced by the model for treatments 1 through 4. Based on the numerical simulation, the ranking of effectiveness in total emission reduction was VIF (82.4%) > Reagent + HDPE (73.2%) > Reagent + Irrigation (43.0%) > Reagent (23.5%) > Deep + HDPE (19.3%) > HOM (17.6%) > Deep (13.0%) > Irrigation (11.9%) > HDPE (5.8%). The order for pest control efficacy suggests, VIF had the highest pest control efficacy, followed by Deep + HDPE, Irrigation, Reagent + Irrigation, HDPE, Deep, Reagent + HDPE, Reagent, and HOM. Therefore, VIF is the optimal method disregarding the cost of the film since it maximizes efficacy while minimizing volatility losses. Otherwise, the integrated methods such as Deep + HDPE and Reagent + Irrigation, are recommended.

Assessment of Uinta Basin Oil and Natural Gas Well Pad Pneumatic Controller Emissions

EPA Science Inventory

In the fall of 2016, a field study was conducted in the Uinta Basin Utah to improve information on oil and natural gas well pad pneumatic controllers (PCs) and emission measurement methods. A total of 80 PC systems at five oil sites (supporting six wells) and three gas sites (sup...

National- to port-level inventories of shipping emissions in China

NASA Astrophysics Data System (ADS)

Fu, Mingliang; Liu, Huan; Jin, Xinxin; He, Kebin

2017-11-01

Shipping in China plays a global role, and has led worldwide maritime transportation for the last decade. However, without taking national or local port boundaries into account, it is impossible to determine the responsibility that each local authority has on emission controls, nor compare them with land-based emissions to determine the priority for controlling these emissions. In this study, we provide national- to port-level inventories for China. The results show that in 2013, the total emissions of CO, non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NO x ), particulate matter (PM), SO2 and CO2 were 0.0741 ± 0.0004 Tg•yr-1, 0.0691 ± 0.0004 Tg•yr-1, 1.91 ± 0.01 Tg•yr-1, 0.164 ± 0.001 Tg•yr-1, 1.30 ± 0.01 Tg•yr-1 and 86.3 ± 0.3 Tg•yr-1 in China, respectively. By providing high-resolution spatial distribution maps of these emissions, we identify three hotspots, centered on the Bohai Rim Area, the Yangtze River Delta and Pearl River Delta. These three hotspots account for 8% of the ocean area evaluated in this study, but contribute around 37% of total shipping emissions. Compared with on-road mobile source emissions, NO x and PM emissions from ships are equivalent to about 34% and 29% of the total mobile vehicle emissions in China. Moreover, this study provides detailed emission inventories for 24 ports in the country, which also greatly contributes to our understanding of global shipping emissions, given that eight of these ports rank within the top twenty of the port league table. Several ports in China suffer emissions 12-147 times higher than those at Los Angeles port. The ports of Ningbo-Zhou Shan, Shanghai, Hong Kong and Dalian dominate the port-level inventories, with individual emissions accounting for 28%-31%, 10%-14%, 10%-12% and 8%-14% of total emissions, respectively.

Fumigation efficacy and emission reduction using low-permeability film in orchard soil fumigation.

PubMed

Gao, Suduan; Sosnoskie, Lynn M; Cabrera, Jose Alfonso; Qin, Ruijun; Hanson, Bradley D; Gerik, James S; Wang, Dong; Browne, Greg T; Thomas, John E

2016-02-01

Many orchards use fumigation to control soilborne pests prior to replanting. Controlling emissions is mandatory to reduce air pollution in California. This research evaluated the effects of plastic film type [polyethylene (PE) or totally impermeable film (TIF)], application rate of Telone C35 [full (610 kg ha(-1) ), 2/3 or 1/3 rates] and carbonation at 207 kPa on fumigant transport (emission and in soil) and efficacy. While increasing fumigant concentrations under the tarp, TIF reduced emissions >95% (∼2% and <1% of total applied 1,3-dichloropropene and chloropicrin respectively) relative to bare soil, compared with ∼30% reduction by PE. All fumigation treatments, regardless of film type, provided good nematode control above 100 cm soil depth; however, nematode survival was high at deeper depths. Weed emergence was mostly affected by tarping and fumigant rate, with no effects from the carbonation. TIF can effectively reduce fumigant emissions. Carbonation under the studied conditions did not improve fumigant dispersion and pest control. The 2/3 rate with TIF controlled nematodes as effectively as the full rate in bare soil or under the PE film to 100 cm soil depth. However, control of nematodes in deeper soil remains a challenge for perennial crops. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

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

... for Hazardous Air Pollutants: Reinforced Plastic Composites Production Testing and Initial Compliance... per year Oc=controlled oven organic HAP emissions, lbs per year R=total usage of neat resin plus, tpy G=total usage of neat gel coat plus, tpy (b) Averaging option. Use Equation 2 of this section to...

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

... Connector 5.59 Open-Ended Line 17.27 Pressure Relief Valve 39.66 Meter 19.33 Population Emission Factors... Population Emission Factors—Other Components, Gas Service Low Continuous Bleed Pneumatic Device Vents 2 1.37... Valves include control valves, block valves and regulator valves. 2 Emission Factor is in units of “scf...

40 CFR 63.2505 - How do I comply with the alternative standard?

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Miscellaneous Organic Chemical... control device(s), it must reduce HAP emissions to an outlet total organic HAP concentration of 50 ppmv or...

Environmental assessment of a firetube boiler firing coal/oil/water mixtures. Volume 1. Technical results. Final report, February 1981-November 1983

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeRosier, R.

1984-09-01

This volume describes emission results from sampling of flue-gas from a firetube boiler burning a coal/oil/water (COW) mixture and COW with soda ash added (COW+SA) to control SO/sub 2/ emissions. Measurements included: continuous monitoring of flue-gas emissions; source assessment sampling system (SASS) sampling of the flue gas with subsequent laboratory analysis of the samples to give total flue gas organics in two boiling point ranges, specific quantitation of the semivolatile organic priority pollutant species, and flue gas concentrations of 73 trace elements; Method 5 sampling for total particulate; and controlled condensation system sampling for SO/sub 2/ and SO/sub 3/ emissions.more » Flue-gas SO/sub 2/ emissions decreased almost 99% with soda ash addition from 1,089 to 13.6 ppm (3% O2). NOx emissions decreased slightly from 477 to 427 ppm, while CO emissions increased significantly from an average of 25 to 426 ppm (all at 3% O2). Particulate loading at the boiler outlet almost doubled (from 1,970 to 3,715 pg/dscm) with the additive. The size distribution of particulate also shifted to a much smaller mean diameter. Total organic emissions increased from 6.7 to 13.1 mg/dscm; most of the increase were nonvolatile (C16+) organics. Of the semivolatile organic priority pollutant species, only fluoranthene and phenanthrene were detected with the COW fuel, and phenanthrene with the COW+SA fuel.« less

Reducing air pollutant emissions at airports by controlling aircraft ground operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gelinas, C.G.; Fan, H.S.L.

1979-02-01

Average-day carbon monoxide, total hydrocarbon, and NO/sub x/ aircraft emissions and fuel use estimates (apportioned to takeoff, taxi, idle, and landing) for departure and arrival at Los Angeles and San Francisco International Airports were compared with emissions level and fuel use estimates for four emission reduction strategies (tow aircraft between runways and gates, shutdown one engine during taxiing, control departure time, and assign runways to minimize taxiing distance). The best strategy, the shutdown of one engine while taxiing, produces substantial emission reductions, cost benefits owing to fuel savings, and no apparent safety problems; aircraft towing reduced emissions significantly, but introducedmore » a number of safety problems.« less

Testing and modeling the influence of reclamation and control methods for reducing nonpoint mercury emissions associated with industrial open pit gold mines.

PubMed

Miller, Matthieu B; Gustin, Mae S

2013-06-01

Industrial gold mining is a significant source of mercury (Hg) emission to the atmosphere. To investigate ways to reduce these emissions, reclamation and dust and mercury control methods used at open pit gold mining operations in Nevada were studied in a laboratory setting. Using this information along with field data, and building off previous work, total annual Hg emissions were estimated for two active gold mines in northern Nevada. Results showed that capping mining waste materials with a low-Hg substrate can reduce Hg emissions from 50 to nearly 100%. The spraying of typical dust control solutions often results in higher Hg emissions, especially as materials dry after application. The concentrated application of a dithiocarbamate Hg control reagent appears to reduce Hg emissions, but further testing mimicking the actual distribution of this chemical within an active leach solution is needed to make a more definitive assessment.

40 CFR Table 5 to Subpart Hhhhh of... - Emission Limits and Work Practice Standards for Transfer Operations

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Halogenated Group 1 transfer operation vent stream for which you use a combustion device to control organic... your transfer operations. For each . . . You must. . . . 1. Group 1 transfer operation vent stream a... system to any combination of control devices (except a flare); or b. Reduce emissions of total organic...

40 CFR Table 5 to Subpart Hhhhh of... - Emission Limits and Work Practice Standards for Transfer Operations

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Halogenated Group 1 transfer operation vent stream for which you use a combustion device to control organic... your transfer operations. For each . . . You must. . . . 1. Group 1 transfer operation vent stream a... system to any combination of control devices (except a flare); or b. Reduce emissions of total organic...

40 CFR Table 5 to Subpart Hhhhh of... - Emission Limits and Work Practice Standards for Transfer Operations

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Halogenated Group 1 transfer operation vent stream for which you use a combustion device to control organic... your transfer operations. For each . . . You must. . . . 1. Group 1 transfer operation vent stream a... system to any combination of control devices (except a flare); or b. Reduce emissions of total organic...

Effects of hydrotreated vegetable oil on emissions of aerosols and gases from light-duty and medium-duty older technology engines.

PubMed

Bugarski, Aleksandar D; Hummer, Jon A; Vanderslice, Shawn

2016-01-01

This study was conducted to assess the potential of hydrotreated vegetable oil renewable diesel (HVORD) as a control strategy to reduce exposure of workers to diesel aerosols and gases. The effects of HVORD on criteria aerosol and gaseous emissions were compared with those of ultralow sulfur diesel (ULSD). The results of comprehensive testing at four steady-state conditions and one transient cycle were used to characterize the aerosol and gaseous emissions from two older technology engines: (1) a naturally aspirated mechanically controlled and (2) a turbocharged electronically controlled engine. Both engines were equipped with diesel oxidation catalytic converters (DOCs). For all test conditions, both engines emitted measurably lower total mass concentrations of diesel aerosols, total carbon, and elemental carbon when HVORD was used in place of ULSD. For all test conditions, the reductions in total mass concentrations were more substantial for the naturally aspirated than for the turbocharged engine. In the case of the naturally aspirated engine, HVORD also favorably affected total surface area of aerosols deposited in the alveolar region of human lungs (TSAADAR) and the total number concentrations of aerosols. In the case of the turbocharged electronically controlled engine, for some of the test conditions HVORD adversely affected the TSAADAR and total number concentrations of aerosols. In the majority of the test cases involving the naturally aspirated mechanically controlled engine, HVORD favorably affected carbon dioxide (CO2), nitrogen oxides (NOX), and nitric oxide (NO) concentrations, but adversely affected NO2 and total hydrocarbon concentrations, while the effects of the fuels on carbon monoxide (CO) concentrations were masked by the effects of DOC. In the case of the turbocharged electronically controlled engine, the CO2, CO, NOX, NO, and total hydrocarbon concentrations were generally lower when HVORD was used in place of ULSD. The effects of the fuels on NO2 concentrations were masked by the more prominent effects of DOC.

Effects of hydrotreated vegetable oil on emissions of aerosols and gases from light-duty andmedium-duty older technology engines

PubMed Central

Bugarski, Aleksandar D.; Hummer, Jon A.; Vanderslice, Shawn

2017-01-01

This study was conducted to assess the potential of hydrotreated vegetable oil renewable diesel (HVORD) as a control strategy to reduce exposure of workers to diesel aerosols and gases. The effects of HVORD on criteria aerosol and gaseous emissions were compared with those of ultralow sulfur diesel (ULSD). The results of comprehensive testing at four steady-state conditions and one transient cycle were used to characterize the aerosol and gaseous emissions from two older technology engines: (1) a naturally aspirated mechanically controlled and (2) a turbocharged electronically controlled engine. Both engines were equipped with diesel oxidation catalytic converters (DOCs). For all test conditions, both engines emitted measurably lower total mass concentrations of diesel aerosols, total carbon, and elemental carbon when HVORD was used in place of ULSD. For all test conditions, the reductions in total mass concentrations were more substantial for the naturally aspirated than for the turbocharged engine. In the case of the naturally aspirated engine, HVORD also favorably affected total surface area of aerosols deposited in the alveolar region of human lungs (TSAADAR) and the total number concentrations of aerosols. In the case of the turbocharged electronically controlled engine, for some of the test conditions HVORD adversely affected the TSAADAR and total number concentrations of aerosols. In the majority of the test cases involving the naturally aspirated mechanically controlled engine, HVORD favorably affected carbon dioxide (CO2), nitrogen oxides (NOX), and nitric oxide (NO) concentrations, but adversely affected NO2 and total hydrocarbon concentrations, while the effects of the fuels on carbon monoxide (CO) concentrations were masked by the effects of DOC. In the case of the turbocharged electronically controlled engine, the CO2, CO, NOX, NO, and total hydrocarbon concentrations were generally lower when HVORD was used in place of ULSD. The effects of the fuels on NO2 concentrations were masked by the more prominent effects of DOC. PMID:26588029

40 CFR 1066.610 - Mass-based and molar-based exhaust emission calculations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Mass-based and molar-based exhaust... (CONTINUED) AIR POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Calculations § 1066.610 Mass-based and molar-based exhaust emission calculations. (a) Calculate your total mass of emissions over a test cycle as...

40 CFR 1066.610 - Mass-based and molar-based exhaust emission calculations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 34 2013-07-01 2013-07-01 false Mass-based and molar-based exhaust... (CONTINUED) AIR POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Calculations § 1066.610 Mass-based and molar-based exhaust emission calculations. (a) Calculate your total mass of emissions over a test cycle as...

Valuation of Water and Emissions in Energy Systems

EPA Science Inventory

Price incentives and economic penalties (monetization) are common approaches to control water usage and total direct greenhouse gas emissions (externalities) of industrial systems. We argue that homogenous pricing of externalities provides limited flexibility for mitigating envir...

AUTOMOTIVE EMISSIONS OF ETHYLENE DIBROMIDE

EPA Science Inventory

Ethylene dibromide, a suspected carcinogen, and ethylene dichloride are commonly used in leaded gasoline as scavengers. Ethylene dibromide emission rates were determined from seven automobiles which had a wide range of control devices, ranging from totally uncontrolled to evapora...

A wood-strand material for wind erosion control: effects on total sediment loss, PM10 vertical flux, and PM10 loss.

PubMed

Copeland, N S; Sharratt, B S; Wu, J Q; Foltz, R B; Dooley, J H

2009-01-01

Fugitive dust from eroding land poses risks to environmental quality and human health, and thus, is regulated nationally based on ambient air quality standards for particulate matter with mean aerodynamic diameter < or = 10 microm (PM10) established in the Clean Air Act. Agricultural straw has been widely used for rainfall-induced erosion control; however, its performance for wind erosion mitigation has been less studied, in part because straw is mobile at moderate wind velocities. A wood-based long-strand material has been developed for rainfall-induced erosion control and has shown operational promise for control of wind-induced erosion and dust emissions from disturbed sites. The purpose of this study was to evaluate the efficacy of both agricultural straw and wood-strand materials in controlling wind erosion and fugitive dust emissions under laboratory conditions. Wind tunnel tests were conducted to compare wood strands of several geometries to agricultural wheat straw and bare soil in terms of total sediment loss, PM10 vertical flux, and PM10 loss. Results indicate that the types of wood strands tested are stable at wind speeds of up to 18 m s(-1), while wheat straw is only stable at speeds of up to 6.5 m s(-1). Wood strands reduced total sediment loss and PM10 emissions by 90% as compared to bare soil across the range of wind speeds tested. Wheat straw did not reduce total sediment loss for the range of speeds tested, but did reduce PM10 emissions by 75% compared to a bare soil at wind speeds of up to 11 m s(-1).

On-road vehicle emissions and their control in China: A review and outlook.

PubMed

Wu, Ye; Zhang, Shaojun; Hao, Jiming; Liu, Huan; Wu, Xiaomeng; Hu, Jingnan; Walsh, Michael P; Wallington, Timothy J; Zhang, K Max; Stevanovic, Svetlana

2017-01-01

The large (26-fold over the past 25years) increase in the on-road vehicle fleet in China has raised sustainability concerns regarding air pollution prevention, energy conservation, and climate change mitigation. China has established integrated emission control policies and measures since the 1990s, including implementation of emission standards for new vehicles, inspection and maintenance programs for in-use vehicles, improvement in fuel quality, promotion of sustainable transportation and alternative fuel vehicles, and traffic management programs. As a result, emissions of major air pollutants from on-road vehicles in China have peaked and are now declining despite increasing vehicle population. As might be expected, progress in addressing vehicle emissions has not always been smooth and challenges such as the lack of low sulfur fuels, frauds over production conformity and in-use inspection tests, and unreliable retrofit programs have been encountered. Considering the high emission density from vehicles in East China, enhanced vehicle, fuel and transportation strategies will be required to address vehicle emissions in China. We project the total vehicle population in China to reach 400-500 million by 2030. Serious air pollution problems in many cities of China, in particular high ambient PM 2.5 concentration, have led to pressure to accelerate the progress on vehicle emission reduction. A notable example is the draft China 6 emission standard released in May 2016, which contains more stringent emission limits than those in the Euro 6 regulations, and adds a real world emission testing protocol and a 48-h evaporation testing procedure including diurnal and hot soak emissions. A scenario (PC[1]) considered in this study suggests that increasingly stringent standards for vehicle emissions could mitigate total vehicle emissions of HC, CO, NO X and PM 2.5 in 2030 by approximately 39%, 57%, 59% and 79%, respectively, compared with 2013 levels. With additional actions to control the future light-duty passenger vehicle population growth and use, and introduce alternative fuels and new energy vehicles, the China total vehicle emissions of HC, CO, NO X and PM 2.5 in 2030 could be reduced by approximately 57%, 71%, 67% and 84%, respectively, (the PC[2] scenario) relative to 2013. This paper provides detailed policy roadmaps and technical options related to these future emission reductions for governmental stakeholders. Copyright © 2016 Elsevier B.V. All rights reserved.

Black carbon emissions from Russian diesel sources. Case study of Murmansk

DOE PAGES

Evans, M.; Kholod, N.; Malyshev, V.; ...

2015-07-27

Black carbon (BC) is a potent pollutant because of its effects on climate change, ecosystems and human health. Black carbon has a particularly pronounced impact as a climate forcer in the Arctic because of its effect on snow albedo and cloud formation. We have estimated BC emissions from diesel sources in the Murmansk Region and Murmansk City, the largest city in the world above the Arctic Circle. In this study we developed a detailed inventory of diesel sources including on-road vehicles, off-road transport (mining, locomotives, construction and agriculture), ships and diesel generators. For on-road transport, we conducted several surveys tomore » understand the vehicle fleet and driving patterns, and, for all sources, we also relied on publicly available local data sets and analysis. We calculated that BC emissions in the Murmansk Region were 0.40 Gg in 2012. The mining industry is the largest source of BC emissions in the region, emitting 69 % of all BC emissions because of its large diesel consumption and absence of emissions controls. On-road vehicles are the second largest source, emitting about 13 % of emissions. Old heavy duty trucks are the major source of emissions. Emission controls on new vehicles limit total emissions from on-road transportation. Vehicle traffic and fleet surveys show that many of the older cars on the registry are lightly or never used. We also estimated that total BC emissions from diesel sources in Russia were 50.8 Gg in 2010, and on-road transport contributed 49 % of diesel BC emissions. Agricultural machinery is also a significant source Russia-wide, in part because of the lack of controls on off-road vehicles.« less

Black carbon emissions from Russian diesel sources. Case study of Murmansk

DOE Office of Scientific and Technical Information (OSTI.GOV)

Evans, M.; Kholod, N.; Malyshev, V.

Black carbon (BC) is a potent pollutant because of its effects on climate change, ecosystems and human health. Black carbon has a particularly pronounced impact as a climate forcer in the Arctic because of its effect on snow albedo and cloud formation. We have estimated BC emissions from diesel sources in the Murmansk Region and Murmansk City, the largest city in the world above the Arctic Circle. In this study we developed a detailed inventory of diesel sources including on-road vehicles, off-road transport (mining, locomotives, construction and agriculture), ships and diesel generators. For on-road transport, we conducted several surveys tomore » understand the vehicle fleet and driving patterns, and, for all sources, we also relied on publicly available local data sets and analysis. We calculated that BC emissions in the Murmansk Region were 0.40 Gg in 2012. The mining industry is the largest source of BC emissions in the region, emitting 69 % of all BC emissions because of its large diesel consumption and absence of emissions controls. On-road vehicles are the second largest source, emitting about 13 % of emissions. Old heavy duty trucks are the major source of emissions. Emission controls on new vehicles limit total emissions from on-road transportation. Vehicle traffic and fleet surveys show that many of the older cars on the registry are lightly or never used. We also estimated that total BC emissions from diesel sources in Russia were 50.8 Gg in 2010, and on-road transport contributed 49 % of diesel BC emissions. Agricultural machinery is also a significant source Russia-wide, in part because of the lack of controls on off-road vehicles.« less

Air Pollutant Emissions Projections for the Cement and Steel Industry in China and the Impact of Emissions Control Technologies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasanbeigi, Ali; Khanna, Nina; Price, Lynn

China’s cement and steel industry accounts for approximately half of the world’s total cement and steel production. These two industries are two of the most energy-intensive and highest carbon dioxide (CO 2)-emitting industries and two of the key industrial contributors to air pollution in China. For example, the cement industry is the largest source of particulate matter (PM) emissions in China, accounting for 40 percent of its industrial PM emissions and 27 percent of its total national PM emissions. The Chinese steel industry contributed to approximately 20 percent of sulfur dioxide (SO 2) emissions and 27 percent of PM emissionsmore » for all key manufacturing industries in China in 2013. In this study, we analyzed and projected the total PM and SO2 emissions from the Chinese cement and steel industry from 2010–2050 under three different scenarios: a Base Case scenario, an Advanced scenario, and an Advanced EOP (end-of-pipe) scenario. We used bottom-up emissions control technologies data and assumptions to project the emissions. In addition, we conducted an economic analysis to estimate the cost for PM emissions reductions in the Chinese cement industry using EOP control technologies, energy efficiency measures, and product change measures. The results of the emissions projection showed that there is not a substantial difference in PM emissions between the Base Case and Advanced scenarios, for both the cement and steel industries. This is mainly because PM emissions in the cement industry caused mainly by production process and not the fuel use. Since our forecast for the cement production in the Base Case and Advanced scenarios are not too different from each other, this results in only a slight difference in PM emissions forecast for these two scenarios. Also, we assumed a similar share and penetration rate of control technologies from 2010 up to 2050 for these two scenarios for the cement and steel industry. However, the Advanced EOP scenario showed significantly lower PM emissions for the cement industry, reaching to 1.7 million tons of PM in 2050, which is less than half of that in the other two scenarios. The Advanced EOP scenario also has the lowest SO2 emissions for the cement industry in China, reaching to 212,000 tons of SO2 in 2050, which is equal to 40 percent of the SO2 emissions in the Advanced scenario and 30 percent of the emissions in the Base Case scenario. The SO2 emission is mainly caused by fuel (coal) burning in cement kiln or steel processes. For the steel industry, the SO2 emissions of the Advanced EOP scenario are significantly lower than the other scenarios, with emissions declining to 323,000 tons in 2050, which is equal to 21 percent and 17 percent of the emissions of Advanced and Base Case scenarios in 2050, respectively. Results of the economic analysis show that for the Chinese cement industry, end-of-pipe PM control technologies have the lowest abatement cost per ton of PM reduced, followed by product change measures and energy efficiency measures, respectively. In summary, in order to meet Chinese national and regional air quality standards, best practice end-of-pipe emissions control technologies must be installed in both cement and steel industry and it must be supplemented by implementation of energy efficiency technologies and reduction of cement and steel production through structural change in industry.« less

40 CFR Table 1b to Subpart Dddd of... - Add-on Control Systems Compliance Options

Code of Federal Regulations, 2011 CFR

2011-07-01

... dryer zones one and two (at new affected sources) (1) Reduce emissions of total HAP, measured as THC (as carbon) a, by 90 percent; or(2) Limit emissions of total HAP, measured as THC (as carbon) a, to 20 ppmvd... are greater than or equal to 10 ppmvd. a You may choose to subtract methane from THC as carbon...

Greenhouse gas emissions control in integrated municipal solid waste management through mixed integer bilevel decision-making.

PubMed

He, Li; Huang, G H; Lu, Hongwei

2011-10-15

Recent studies indicated that municipal solid waste (MSW) is a major contributor to global warming due to extensive emissions of greenhouse gases (GHGs). However, most of them focused on investigating impacts of MSW on GHG emission amounts. This study presents two mixed integer bilevel decision-making models for integrated municipal solid waste management and GHG emissions control: MGU-MCL and MCU-MGL. The MGU-MCL model represents a top-down decision process, with the environmental sectors at the national level dominating the upper-level objective and the waste management sectors at the municipal level providing the lower-level objective. The MCU-MGL model implies a bottom-up decision process where municipality plays a leading role. Results from the models indicate that: the top-down decisions would reduce metric tonne carbon emissions (MTCEs) by about 59% yet increase about 8% of the total management cost; the bottom-up decisions would reduce MTCE emissions by about 13% but increase the total management cost very slightly; on-site monitoring and downscaled laboratory experiments are still required for reducing uncertainty in GHG emission rate from the landfill facility. Copyright © 2011 Elsevier B.V. All rights reserved.

Methanator Fueled Engines for Pollution Control

NASA Technical Reports Server (NTRS)

Cagliostro, D. E.; Winkler, E. L.

1973-01-01

A methanator fueled Otto-cycle engine is compared with other methods proposed to control pollution due to automobile exhaust emissions. The comparison is made with respect to state of development, emission factors, capital cost, operational and maintenance costs, performance, operational limitations, and impact on the automotive industries. The methanator fueled Otto-cycle engine is projected to meet 1975 emission standards and operate at a lower relative total cost compared to the catalytic muffler system and to have low impact. Additional study is required for system development.

Environmental assessment of NH3 injection for an industrial package boiler. Volume 2. Data supplement. Final report, January 1983-January 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castaldini, C.; DeRosier, R.; Waterland, L.R.

1986-02-01

The report discusses emission results from comprehensive flue-gas sampling of a gas- and oil-fired industrial boiler equipped with Exxon's Thermal DeNOx Ammonia Injection Process for NOx reduction. Comprehensive emission measurements included continuous monitoring of flue gas emissions; source assessment sampling system (SASS) tests; EPA Method 5/17 for solid and condensible particulate emissions and ammonia emissions; controlled condensation system for SO2 and SO3; and N2O emission sampling. Ammonia injection at a NH3/NO molar ratio of 2.52 gave a NOx reduction of 41% from an uncontrolled level of 234 ppm to a controlled level of 137 ppm. NH3 emissions increased from 11more » ppm for the baseline to an average of 430 ppm for ammonia injection. Nitrous oxide, N2O, was reduced 68% from a 50 ppm baseline level to a 17 ppm controlled level. Total particulate emissions increased by an order of magnitude from a baseline of 17.7 ng/J to a controlled level of 182 ng/J.« less

Inventory of U.S. 2012 dioxin emissions to atmosphere.

PubMed

Dwyer, Henri; Themelis, Nickolas J

2015-12-01

In 2006, the U.S. EPA published an inventory of dioxin emissions for the U.S. covering the period from 1987-2000. This paper is an updated inventory of all U.S. dioxin emissions to the atmosphere in the year 2012. The sources of emissions of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), collectively referred to in this paper as "dioxins", were separated into two classes: controlled industrial and open burning sources. Controlled source emissions decreased 95.5% from 14.0 kg TEQ in 1987 to 0.6 kg in 2012. Open burning source emissions increased from 2.3 kg TEQ in 1987 to 2.9 kg in 2012. The 2012 dioxin emissions from 53 U.S. waste-to-energy (WTE) power plants were compiled on the basis of detailed data obtained from the two major U.S. WTE companies, representing 84% of the total MSW combusted (27.4 million metric tons). The dioxin emissions of all U.S. WTE plants in 2012 were 3.4 g TEQ and represented 0.54% of the controlled industrial dioxin emissions, and 0.09% of all dioxin emissions from controlled and open burning sources. Copyright © 2015. Published by Elsevier Ltd.

Effects of After-Treatment Control Technologies on Heavy-Duty Diesel Truck Emissions

NASA Astrophysics Data System (ADS)

Preble, C.; Dallmann, T. R.; Kreisberg, N. M.; Hering, S. V.; Harley, R.; Kirchstetter, T.

2015-12-01

Diesel engines are major emitters of nitrogen oxides (NOx) and the black carbon (BC) fraction of particulate matter (PM). Diesel particle filter (DPF) and selective catalytic reduction (SCR) emission control systems that target exhaust PM and NOx have recently become standard on new heavy-duty diesel trucks (HDDT). There is concern that DPFs may increase ultrafine particle (UFP) and total particle number (PN) emissions while reducing PM mass emissions. Also, the deliberate catalytic oxidation of engine-out NO to NO2 in continuously regenerating DPFs may lead to increased tailpipe emission of NO2 and near-roadway concentrations that exceed the 1-hr national ambient air quality standard. Increased NO2 emissions can also promote formation of ozone and secondary PM. We report results from ongoing on-road studies of HDDT emissions at the Port of Oakland and the Caldecott Tunnel in California's San Francisco Bay Area. Emission factors (g pollutant per kg diesel) were linked via recorded license plates to each truck's engine model year and installed emission controls. At both sites, DPF use significantly increased the NO2/NOx emission ratio. DPFs also significantly increased NO2 emissions when installed as retrofits on older trucks with higher baseline NOx emissions. While SCR systems on new trucks effectively reduce total NOx emissions and mitigate these undesirable DPF-related NO2 emissions, they also lead to significant emission of N2O, a potent greenhouse gas. When expressed on a CO2-equivalent basis, the N2O emissions increase offsets the fuel economy gain (i.e., the CO2 emission reduction) associated with SCR use. At the Port, average NOx, BC and PN emission factors from new trucks equipped with DPF and SCR were 69 ± 15%, 92 ± 32% and 66 ± 35% lower, respectively, than modern trucks without these emission controls. In contrast, at the Tunnel, PN emissions from older trucks retrofit with DPFs were ~2 times greater than modern trucks without DPFs. The difference could be related to engine temperature, with highway operation producing greater exhaust temperatures that promote UFP nucleation. These studies indicate that DPF and SCR use can mitigate air quality and climate impacts of diesel truck emissions through reductions in BC and NOx. However, increased emissions of N2O, NO2 and PN may offset some of the benefits.

Hot emission model for mobile sources: application to the metropolitan region of the city of Santiago, Chile.

PubMed

Corvalán, Roberto M; Osses, Mauricio; Urrutia, Cristian M

2002-02-01

Depending on the final application, several methodologies for traffic emission estimation have been developed. Emission estimation based on total miles traveled or other average factors is a sufficient approach only for extended areas such as national or worldwide areas. For road emission control and strategies design, microscale analysis based on real-world emission estimations is often required. This involves actual driving behavior and emission factors of the local vehicle fleet under study. This paper reports on a microscale model for hot road emissions and its application to the metropolitan region of the city of Santiago, Chile. The methodology considers the street-by-street hot emission estimation with its temporal and spatial distribution. The input data come from experimental emission factors based on local driving patterns and traffic surveys of traffic flows for different vehicle categories. The methodology developed is able to estimate hourly hot road CO, total unburned hydrocarbons (THCs), particulate matter (PM), and NO(x) emissions for predefined day types and vehicle categories.

VOC/HAP control systems for the shipbuilding and aerospace industries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lukey, M.E.; Toothman, D.A.

1999-07-01

Compliant coating systems, i.e., those which meet limits on pounds of volatile organic compound (VOC)/hazardous air pollutant (HAP) per gallon, on a solids applied basis, are routinely used to meet emission regulations in the shipbuilding and aerospace industries. However, there are occasions when solvent based systems must be used. Total capture and high destruction of the solvents in those systems is necessary in order to meet the required emission limit, e.g., a reasonably available control technology (RACT) limit of 3.5lbs of VOC/gallon. Water based marine coatings and certain aerospace finish coats do not provide sufficient longevity or meet other customermore » specifications in these instances. Furthermore, because of best available control technology (BACT) determinations or facility limits for operation in serious, severe, and extreme nonattainment areas, it is necessary to reduce annual emissions to levels which are below the levels required by the coating standards. The paper discusses those operations for controlling emissions from large-scale solvent based painting and coating systems in those instances when a high degree of overall control is required. Permanent total enclosures (stationary and portable), concentrators, regenerative thermal oxidizers, and other air pollution control systems are evaluated, both for technical applicability and economic feasibility. Several case studies are presented which illustrate techniques for capturing painting emissions, options for air handling in the workplace, and methods for destroying exhaust stream VOC concentrations of less than 40 ppm.« less

Photosynthetic photon flux, photoperiod, and temperature effects on emissions of (Z)-3-hexenal, (Z)-3-hexenol, and (Z)-3-hexenyl acetate from lettuce

NASA Technical Reports Server (NTRS)

Charron, C. S.; Cantliffe, D. J.; Wheeler, R. M.; Manukian, A.; Heath, R. R.

1996-01-01

To investigate the effects of environment on plant volatile emissions, 'Waldmann's Green' leaf lettuce was cultivated under different levels of photosynthetic photon flux (PPF), photoperiod, and temperature. A modified growth chamber was used to sample plant volatile emissions nondestructively, over time, and under controlled conditions. Total volatile emission rates were significantly higher from lettuce cultivated under PPF of 360 or 200 micromoles m-2 s-1 compared to 105 micromoles m-2 s-1, and significantly higher under a 16-h photoperiod than an 8-h photoperiod. No differences were detected among emission rates from different temperature treatments. In controlled environments, emissions could be regulated by adjusting environmental conditions accordingly.

Study on the total amount control of atmospheric pollutant based on GIS.

PubMed

Wang, Jian-Ping; Guo, Xi-Kun

2005-08-01

To provide effective environmental management for total amount control of atmospheric pollutants. An atmospheric diffusion model of sulfur dioxide on the surface of the earth was established and tested in Shantou of Guangdong Province on the basis of an overall assessment of regional natural environment, social economic state of development, pollution sources and atmospheric environmental quality. Compared with actual monitoring results in a studied region, simulation values fell within the range of two times of error and were evenly distributed in the two sides of the monitored values. Predicted with the largest emission model method, the largest emission of sulfur dioxide would be 54,279.792 tons per year in 2010. The mathematical model established and revised on the basis of GIS is more rational and suitable for the regional characteristics of total amount control of air pollutants.

Biochar increases nitrogen retention and lowers greenhouse gas emissions when added to composting poultry litter.

PubMed

Agyarko-Mintah, Eunice; Cowie, Annette; Singh, Bhupinder Pal; Joseph, Stephen; Van Zwieten, Lukas; Cowie, Alan; Harden, Steven; Smillie, Robert

2017-03-01

Biochar has intrinsic and nascent structural and sorption properties that may alter the physical and chemical properties of a composting mixture thus influencing the production of greenhouse gases [GHGs; nitrous oxide (N 2 O) and methane (CH 4 )]. In this study, contrasting biochars produced from greenwaste (GWB) or poultry litter (PLB) were incorporated into a composting mixture containing poultry litter and straw, and GHG emissions were measured in situ during composting using Fourier Transform Infrared Spectroscopy (FTIR). Emissions of N 2 O from the biochar-amended composting mixtures decreased significantly (P<0.05) soon after commencement of the composting process compared with the non-amended control. The cumulative emissions of N 2 O over 8weeks in the GWB composting mixture (GWBC), PLB composting mixture (PLBC) and control (no biochar) were 4.2, 5.0 and 14.0gN 2 O-Nkg -1 of total nitrogen (TN) in composting mixture, respectively (P<0.05). The CH 4 emissions were significantly (P<0.05) lower in the GWBC and PLBC treatments than the control during the period from day 8 to day 36, when anaerobic conditions likely prevailed. The cumulative CH 4 emissions were 12, 18 and 80mg CH 4 -Ckg -1 of total carbon (TC) for the GWBC, PLBC and control treatments, respectively, though due to wide variation between replicates this difference was not statistically significant. The cumulative N 2 O and CH 4 emissions were similar between the GWBC and PLBC despite differences in properties of the two biochars. X-ray Photoelectron Spectroscopy (XPS) analysis and SEM imaging of the composted biochars indicated the presence of iron oxide compounds and amine-NH 3 on the surface and pores of the biochars (PLB>GWB). The change in nitrogen (N) functional groups on the biochar surface after composting is evidence for sorption and/or reaction with N from labile organic N, mineral N, and gaseous N (e.g. N 2 O). The concentration of NH 4 + increased during the thermophilic phase and then decreased during the maturation phase, while NO 3 - accumulated during the maturation phase. Total N retained was significantly (P<0.05) higher in the PLBC (740g) and the GWBC (660g) relative to the control (530g). The TC retained was significantly higher in the GWBC (10.0kg) and the PLBC (8.5kg) cf. the control (6.0kg). Total GHG emissions across the composting period were 50, 63 and 183kg CO 2 -eqt -1 of initial mass of GWBC, PLBC and control (dry weight basis) respectively. These results support the co-composting of biochar to lower net emissions of GHGs while increasing N retention (and fertiliser N value) in the mature compost. Copyright © 2016. Published by Elsevier Ltd.

40 CFR 63.1333 - Additional requirements for performance testing.

Code of Federal Regulations, 2010 CFR

2010-07-01

... paragraphs (b)(1) and (b)(2) of this section. ER19JN00.041 Where: ERMBS = Emission rate of organic HAP or TOC from continuous process vents, kg/Mg product. Ei = Emission rate of organic HAP or TOC from continuous... hours in a year for control device j. Ei=Mass rate of TOC or total organic HAP at the inlet of control...

A high-resolution air pollutants emission inventory in 2013 for the Beijing-Tianjin-Hebei region, China

NASA Astrophysics Data System (ADS)

Qi, Ji; Zheng, Bo; Li, Meng; Yu, Fang; Chen, Chuchu; Liu, Fei; Zhou, Xiafei; Yuan, Jing; Zhang, Qiang; He, Kebin

2017-12-01

We developed a high-resolution Beijing-Tianjin-Hebei (BTH) regional air pollutants emission inventory for the year 2013. The inventory was established using a bottom-up approach based on facility-level activity data obtained from multiple data sources. The estimates from the BTH 2013 emission inventory show that the total emissions of SO2, NOX, PM2.5, PM10, CO, NMVOC, NH3, BC, and OC were 2,305, 2,686, 1,090, 1,494, 20,567, 2,207, 623, 160, and 254 Gg, respectively. The industry sector is the largest emissions source for SO2, NOX, PM2.5, PM10, CO, and NMVOC in the BTH region, contributing 72.6%, 43.7%, 59.6%, 64.7%, 60.3%, and 70.4% of the total emissions, respectively. Power plants contributed 11.8% and 23.3% of the total SO2 and NOX emissions, respectively. The transportation sector contributed 28.9% of the total NOX emissions. Emissions from the residential sector accounted for 31.3%, 21.5%, 46.6% and 71.7% of the total PM2.5, NMVOC, BC and OC emissions, respectively. In addition, more than 90% of the total NH3 emissions originate from the agriculture sector, with 44.2% from fertilizer use and 47.7% from livestock. The spatial distribution results illustrate that air pollutant emissions are mainly distributed over the eastern and southern BTH regions. Beijing, Tianjin, Shijiazhuang, Tangshan and Handan are the major contributors of air pollutants. The major NMVOC species in the BTH region are ethylene, acetylene, ethane and toluene. Ethylene is the biggest contributor in Tianjin and Hebei. The largest contributor in Beijing is toluene. There is relatively low uncertainty in SO2 and NOX emission estimates, medium uncertainty in PM2.5, PM10 and CO emission estimates, and high uncertainties in VOC, NH3, BC and OC emission estimates. The proposed policy recommendations, based on the BTH 2013 emission inventory, would be helpful to develop strategies for air pollution control.

Effect of current emission abatement strategies on air quality improvement in China: A case study of Baotou, a typical industrial city in Inner Mongolia.

PubMed

Qiu, Xionghui; Duan, Lei; Cai, Siyi; Yu, Qian; Wang, Shuxiao; Chai, Fahe; Gao, Jian; Li, Yanping; Xu, Zhaoming

2017-07-01

The national Air Pollution Prevention and Control Action Plan required significant decreases in PM 2.5 levels over China. To explore more effective emission abatement strategies in industrial cities, a case study was conducted in Baotou to evaluate the current national control measures. The total emissions of SO 2, NO X , PM 2.5 and NMVOC (non-methane volatile organic compounds) in Baotou were 211.2Gg, 156.1Gg, 28.8Gg, and 48.5Gg, respectively in 2013, and they would experience a reduction of 30.4%, 26.6%, 15.1%, and 8.7%, respectively in 2017 and 39.0%, 32.0%, 24.4%, and 12.9%, respectively in 2020. The SO 2 , NO X and PM 2.5 emissions from the industrial sector would experience a greater decrease, with reductions of 37%, 32.7 and 24.3%, respectively. From 2013 to 2020, the concentrations of SO 2 , NO 2 , and PM 2.5 are expected to decline by approximately 30%, 10% and 14.5%, respectively. The reduction rate of SNA (sulfate, nitrate and ammonium) concentrations was significantly higher than that of PM 2.5 in 2017, implying that the current key strategy toward controlling air pollutants from the industrial sector is more powerful for SNA. Although air pollution control measures implemented in the industrial sector could greatly reduce total emissions, constraining the emissions from lower sources such as residential coal combustion would be more effective in decreasing the concentration of PM 2.5 from 2017 to 2020. These results suggest that even for a typical industrial city, the reduction of PM 2.5 concentrations not only requires decreases in emissions from the industrial sector, but also from the low emission sources. The seasonal variation in sulfate concentration also showed that emission from coal-burning is the key factor to control during the heating season. Copyright © 2016. Published by Elsevier B.V.

Long-term trends in California mobile source emissions and ambient concentrations of black carbon and organic aerosol.

PubMed

McDonald, Brian C; Goldstein, Allen H; Harley, Robert A

2015-04-21

A fuel-based approach is used to assess long-term trends (1970-2010) in mobile source emissions of black carbon (BC) and organic aerosol (OA, including both primary emissions and secondary formation). The main focus of this analysis is the Los Angeles Basin, where a long record of measurements is available to infer trends in ambient concentrations of BC and organic carbon (OC), with OC used here as a proxy for OA. Mobile source emissions and ambient concentrations have decreased similarly, reflecting the importance of on- and off-road engines as sources of BC and OA in urban areas. In 1970, the on-road sector accounted for ∼90% of total mobile source emissions of BC and OA (primary + secondary). Over time, as on-road engine emissions have been controlled, the relative importance of off-road sources has grown. By 2010, off-road engines were estimated to account for 37 ± 20% and 45 ± 16% of total mobile source contributions to BC and OA, respectively, in the Los Angeles area. This study highlights both the success of efforts to control on-road emission sources, and the importance of considering off-road engine and other VOC source contributions when assessing long-term emission and ambient air quality trends.

Evaluation of costs associated with atmospheric mercury emission reductions from coal combustion in China in 2010 and projections for 2020.

PubMed

Zhang, Yue; Ye, Xuejie; Yang, Tianjun; Li, Jinling; Chen, Long; Zhang, Wei; Wang, Xuejun

2018-01-01

Coal combustion is the most significant anthropogenic mercury emission source in China. In 2013, China signed the Minamata Convention affirming that mercury emissions should be controlled more strictly. Therefore, an evaluation of the costs associated with atmospheric mercury emission reductions from China's coal combustion is essential. In this study, we estimated mercury abatement costs for coal combustion in China for 2010, based on a provincial technology-based mercury emission inventory. In addition, four scenarios were used to project abatement costs for 2020. Our results indicate that actual mercury emission related to coal combustion in 2010 was 300.8Mg, indicating a reduction amount of 174.7Mg. Under a policy-controlled scenario for 2020, approximately 49% of this mercury could be removed using air pollution control devices, making mercury emissions in 2020 equal to or lower than in 2010. The total abatement cost associated with mercury emissions in 2010 was 50.2×10 9 RMB. In contrast, the total abatement costs for 2020 under baseline versus policy-controlled scenarios, having high-energy and low-energy consumption, would be 32.0×10 9 versus 51.2×10 9 , and 27.4×10 9 versus 43.9×10 9 RMB, respectively. The main expense is associated with flue gas desulfurization. The unit abatement cost of mercury emissions in 2010 was 288×10 3 RMB/(kgHg). The unit abatement costs projected for 2020 under a baseline, a policy-controlled, and an United Nations Environmental Programme scenario would be 143×10 3 , 172×10 3 and 1066×10 3 RMB/(kgHg), respectively. These results are much lower than other international ones. However, the relative costs to China in terms of GPD are higher than in most developed countries. We calculated that abatement costs related to mercury emissions accounted for about 0.14% of the GDP of China in 2010, but would be between 0.03% and 0.06% in 2020. This decrease in abatement costs in terms of GDP suggests that various policy-controlled scenarios would be viable. Copyright © 2017 Elsevier B.V. All rights reserved.

Evaluating the effects of China's pollution control on inter-annual trends and uncertainties of atmospheric mercury emissions

NASA Astrophysics Data System (ADS)

Zhao, Y.; Zhong, H.; Zhang, J.; Nielsen, C. P.

2014-10-01

China's atmospheric mercury (Hg) emissions of anthropogenic origin have been effectively restrained through the national policy of air pollution control. Improved methods based on available field measurements are developed to quantify the benefits of Hg abatement through various emission control measures. Those measures include increased use of flue gas desulfurization (FGD) and selective catalyst reduction (SCR) systems for power sector, precalciners with fabric filter (FF) for cement production, machinery coking with electrostatic precipitator (ESP) for iron and steel production, and advanced manufacturing technologies for nonferrous metal smelting. Declining trends in emissions factors for those sources are revealed, leading to a much slower growth of national total Hg emissions than that of energy and economy, from 679 in 2005 to 750 metric tons (t) in 2012. In particular, nearly half of emissions from the above-mentioned four types of sources are expected to be reduced in 2012, attributed to expansion of technologies with high energy efficiencies and air pollutant removal rates after 2005. The speciation of Hg emissions keeps stable for recent years, with the mass fractions of around 55, 39 and 6% for Hg0, Hg2+ and Hgp, respectively. The lower estimate of Hg emissions than previous inventories is supported by limited chemistry simulation work, but middle-to-long term observation on ambient Hg levels is further needed to justify the inter-annual trends of estimated Hg emissions. With improved implementation of emission controls and energy saving, 23% reduction in annual Hg emissions for the most optimistic case in 2030 is expected compared to 2012, with total emissions below 600 t. While Hg emissions are evaluated to be gradually constrained, increased uncertainties are quantified with Monte-Carlo simulation for recent years, particularly for power and certain industrial sources. The uncertainty of Hg emissions from coal-fired power plants, as an example, increased from -48~ +73% in 2005 to -50~ +89% in 2012 (expressed as 95% confidence interval). This is attributed mainly to swiftly increased penetration of advanced manufacturing and pollutant control technologies. The unclear operation status or relatively small sample size of field measurements on those technologies results in lower but highly varied emission factors. To further confirm the benefits of pollution control polices with reduced uncertainty, therefore, systematic investigations are recommended specific for Hg pollution sources, and the variability of temporal trends and spatial distributions of Hg emissions need to be better tracked for the country under dramatic changes in economy, energy and air pollution status.

Characterization of polychlorinated dibenzo-p-dioxin/dibenzofuran emissions from joss paper burned in a furnace with air pollution control devices.

PubMed

Hu, Ming-Tsan; Chen, Shui-Jen; Huang, Kuo-Lin; Lin, Yuan-Chung; Chang-Chien, Guo-Ping; Tsai, Jen-Hsiung

2009-05-01

Burning joss paper, a common practice in temples in some Asian countries, can release toxic pollutants. This study investigated polychlorinated dibenzo-p-dioxin/dibenzofuran (PCDD/F) emissions and profiles from burning joss paper in a temple furnace connected to two wet scrubbers. The mean total PCDD/F content and corresponding toxic equivalent quantity (TEQ) in joss paper were 193 ng kg(-1) and 0.645 ng I-TEQ kg(-1), respectively, whereas those in bottom ash from burned joss paper were 18.5 ng kg(-1) and 1.92 ng I-TEQ kg(-1), respectively. The wet scrubbers decreased individual PCDD/F emissions by 26.7-71.0% and those of total PCDD/Fs and I-TEQ by 47.2% and 66.0%, respectively. The total PCDD/F TEQ emission factors before and after the wet scrubbers were 8.14 and 3.42 microg I-TEQ ton-feedstock(-1), respectively. The estimated total PCDD/F and corresponding TEQ emissions were 5.29 g year(-1) and 0.462 g I-TEQ year(-1), respectively, in Taiwan. Burning joss paper in temple furnaces is a significant source of PCDD/F emissions.

Effectiveness of national air pollution control policies on the air quality in metropolitan areas of China.

PubMed

Wang, Shuxiao; Xing, Jia; Zhao, Bin; Jang, Carey; Hao, Jiming

2014-01-01

Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide (SO2) control policy during the 11th Five Year Plan period (2006-2010) had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate (SO4(2-)) concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides (NO(x)) control policy during the 12th Five Year Plan period (2011-2015) targets the reduction of the national NO(x) emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NO(x) emission will reduce the ambient nitrogen dioxide (NO2), nitrate (NO3(-)), 1-hr maxima ozone (O3) concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%-4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3(-), 1-hr maxima O(3 concentrations and total nitrogen deposition by 2%-4%, 1%-6%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.

Sulfur dioxide and nitrogen oxides emissions from U.S. pulp and paper mills, 1980-2005.

PubMed

Pinkerton, John E

2007-08-01

Comprehensive surveys conducted at 5-yr intervals were used to estimate sulfur dioxide (SO,) and nitrogen oxides (NO.) emissions from U.S. pulp and paper mills for 1980, 1985, 1990, 1995, 2000, and 2005. Over the 25-yr period, paper production increased by 50%, whereas total SO, emissions declined by 60% to 340,000 short tons (t) and total NO, emissions decreased approximately 15% to 230,000 t. The downward emission trends resulted from a combination of factors, including reductions in oil and coal use, steadily declining fuel sulfur content, lower pulp and paper production in recent years, increased use of flue gas desulfurization systems on boilers, growing use of combustion modifications and add-on control systems to reduce boiler and gas turbine NO, emissions, and improvements in kraft recovery furnace operations.

Seasonal and interannual variations in whole-ecosystem BVOC emissions from a subtropical plantation in China

NASA Astrophysics Data System (ADS)

Bai, Jianhui; Guenther, Alex; Turnipseed, Andrew; Duhl, Tiffany; Greenberg, James

2017-07-01

Measurements of BVOC emissions, ozone concentration and environmental parameters were carried out from May 2013 to January 2016 in a subtropical Pinus plantation in China. Isoprene and monoterpene emissions were measured using a relaxed eddy accumulation (REA) system and a gradient technique on an above-canopy tower. In 2013, isoprene comprised 21.2% of total terpenoid emissions, while α-pinene, camphene, β-pinene and limonene constituting 51.5%, 2.4%, 9.1%, and 13.0% of total emissions, respectively. Monoterpenes together were the dominant VOCs measured contributing 71.6%. α-pinene, camphene, β-pinene and limonene constituted 67.7%, 3.2%, 11.9%, 17.2% of total monoterpene emissions. Isoprene and monoterpene emissions displayed strong diurnal variations, with lower emissions in the morning and late evening, and the highest emissions around noon. BVOC peak emissions typically occurred a few hours after the noon PAR peak. Isoprene and monoterpene emissions varied with season and were the highest in summer, contributing more than half of the total annual emission, and the lowest emissions were in winter. Evident interannual variations of isoprene, monoterpenes and total BVOCs were observed. Compared to 2013, annual BVOC emissions decreased in 2015, associated with decreases of PAR, Temperature, water vapor, and an increase of all substances in gas, liquid and solid phases in the atmospheric column (e.g., S/Q, the ratio of solar scattered radiation to global radiation). Ozone concentration showed clear diurnal variation with PAR, higher around noon and lower in the early morning and late evening. Generally, there were no evident correlations between ozone concentrations and BVOC emissions, or the vertical gradients of ozone concentrations and BVOC concentrations. Under all sky conditions (including cloudy skies), no strong correlations at a high confidence level or very similar variation patterns were observed between any two following parameters, BVOC emissions, PAR, temperature, water vapor, and S/Q. The major factors controlling BVOC emissions were PAR and temperature but biomass burning smoke and phenology (pine florescence) may also play a role. The mean emission factors at standard conditions determined using the MEGAN model emission algorithms and empirical model of BVOC emissions were 0.71 and 1.19 mg m-2 h-1 for isoprene and 1.39 and 1.65 mg m-2 h-1 for total monoterpenes, respectively.

[Inventories of atmospheric arsenic emissions from coal combustion in China, 2005].

PubMed

Tian, He-Zhong; Qu, Yi-Ping

2009-04-15

Anthropogenic arsenic (As) emitted from coal combustion is one of key trace elements leading to negative air pollution and national economy loss. It is of great significance to estimate the atmospheric arsenic emission for proposing relevant laws or regulations and selecting proper pollution control technologies. The inventories of atmospheric arsenic emissions from coal combustion in China were evaluated by adopting the emission factor method based on fuel consumption. Arsenic emission sources were firstly classified into several categories by economic sectors, combustion types and pollution control technologies. Then, according to provincial coal consumption and averaged arsenic concentration in the feed fuel, the inventories of atmospheric arsenic emission from coal combustion in China in 2005 were established. Coal outputand consumption in China in 2005 were 2,119.8 and 2,099.8 Mt, respectively. The total emissions of arsenic released into the atmosphere in 2005 in China were estimated at about 1,564.4 t, and Shandong ranked the largest province with 144.4 t arsenic release, followed by Hunan (141.1 t), Hebei (108.5 t), Henan (77.7 t), and Jiangsu (77.0 t), which were mainly concentrated in the eastern and central provinces of China. The arsenic emissions were largely emitted by industry sector (818.8 t) and thermal power generation sector (303.4 t), contributing 52.3% and 19.4% of the totals, respectively. About 375.5 t arsenic was estimated to be released into the atmosphere in the form of gas phase in China in 2005, with a share of 24% of the totals. In general, arsenic pollution control from coal combustion should be highlighted for the power and industry sectors in the whole country. However, arsenic poisoning caused by residential coal burning should also be paid great attention in some areas such as Xinjiang, Gansu, Qinghai and Guishou.

The contribution of evaporative emissions from gasoline vehicles to the volatile organic compound inventory in Mexico City.

PubMed

Schifter, I; Díaz, L; Rodríguez, R; González-Macías, C

2014-06-01

The strategy for decreasing volatile organic compound emissions in Mexico has been focused much more on tailpipe emissions than on evaporative emissions, so there is very little information on the contribution of evaporative emissions to the total volatile organic compound inventory. We examined the magnitudes of exhaust and evaporative volatile organic compound emissions, and the species emitted, in a representative fleet of light-duty gasoline vehicles in the Metropolitan Area of Mexico City. The US "FTP-75" test protocol was used to estimate volatile organic compound emissions associated with diurnal evaporative losses, and when the engine is started and a journey begins. The amount and nature of the volatile organic compounds emitted under these conditions have not previously been accounted in the official inventory of the area. Evaporative emissions from light-duty vehicles in the Metropolitan Area of Mexico City were estimated to be 39 % of the total annual amount of hydrocarbons emitted. Vehicles built before 1992 (16 % of the fleet) were found to be responsible for 43 % of the total hydrocarbon emissions from exhausts and 31 % of the evaporative emissions of organic compounds. The relatively high amounts of volatile organic compounds emitted from older vehicles found in this study show that strong emission controls need to be implemented in order to decrease the contribution of evaporative emissions of this fraction of the fleet.

40 CFR 63.496 - Back-end process provisions-procedures to determine compliance using control or recovery devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... total organic HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary... TOC (minus methane and ethane) may be measured instead of total organic HAP. (C) The mass rates shall... and outlet of the control device shall be the sum of all total organic HAP (or TOC, minus methane and...

Benefits of biochar, compost and biochar-compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil.

PubMed

Agegnehu, Getachew; Bass, Adrian M; Nelson, Paul N; Bird, Michael I

2016-02-01

Soil quality decline represents a significant constraint on the productivity and sustainability of agriculture in the tropics. In this study, the influence of biochar, compost and mixtures of the two on soil fertility, maize yield and greenhouse gas (GHG) emissions was investigated in a tropical Ferralsol. The treatments were: 1) control with business as usual fertilizer (F); 2) 10 t ha(-1) biochar (B)+F; 3) 25 t ha(-1) compost (Com)+F; 4) 2.5 t ha(-1) B+25 t ha(-1) Com mixed on site+F; and 5) 25 t ha(-1) co-composted biochar-compost (COMBI)+F. Total aboveground biomass and maize yield were significantly improved relative to the control for all organic amendments, with increases in grain yield between 10 and 29%. Some plant parameters such as leaf chlorophyll were significantly increased by the organic treatments. Significant differences were observed among treatments for the δ(15)N and δ(13)C contents of kernels. Soil physicochemical properties including soil water content (SWC), total soil organic carbon (SOC), total nitrogen (N), available phosphorus (P), nitrate-nitrogen (NO3(-)N), ammonium-nitrogen (NH4(+)-N), exchangeable cations and cation exchange capacity (CEC) were significantly increased by the organic amendments. Maize grain yield was correlated positively with total biomass, leaf chlorophyll, foliar N and P content, SOC and SWC. Emissions of CO2 and N2O were higher from the organic-amended soils than from the fertilizer-only control. However, N2O emissions generally decreased over time for all treatments and emission from the biochar was lower compared to other treatments. Our study concludes that the biochar and biochar-compost-based soil management approaches can improve SOC, soil nutrient status and SWC, and maize yield and may help mitigate greenhouse gas emissions in certain systems. Copyright © 2015. Published by Elsevier B.V.

Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil

PubMed Central

Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

2018-01-01

A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions. PMID:29394272

Effect of dolomite and biochar addition on N2O and CO2 emissions from acidic tea field soil.

PubMed

Oo, Aung Zaw; Sudo, Shigeto; Akiyama, Hiroko; Win, Khin Thuzar; Shibata, Akira; Yamamoto, Akinori; Sano, Tomohito; Hirono, Yuhei

2018-01-01

A laboratory study was conducted to study the effects of liming and different biochar amendments on N2O and CO2 emissions from acidic tea field soil. The first experiment was done with three different rates of N treatment; N 300 (300 kg N ha-1), N 600 (600 kg N ha-1) and N 900 (900 kg N ha-1) and four different rates of bamboo biochar amendment; 0%, 0.5%, 1% and 2% biochar. The second experiment was done with three different biochars at a rate of 2% (rice husk, sawdust, and bamboo) and a control and lime treatment (dolomite) and control at two moisture levels (50% and 90% water filled pore space (WFPS)). The results showed that dolomite and biochar amendment significantly increased soil pH. However, only biochar amendment showed a significant increase in total carbon (C), C/N (the ratio of total carbon and total nitrogen), and C/IN ratio (the ratio of total carbon and inorganic nitrogen) at the end of incubation. Reduction in soil NO3--N concentration was observed under different biochar amendments. Bamboo biochar with the rates of 0.5, 1 and 2% reduced cumulative N2O emission by 38%, 48% and 61%, respectively, compare to the control soil in experiment 1. Dolomite and biochar, either alone or combined significantly reduced cumulative N2O emission by 4.6% to 32.7% in experiment 2. Reduction in N2O production under biochar amendment was due to increases in soil pH and decreases in the magnitude of mineral-N in soil. Although, both dolomite and biochar increased cumulative CO2 emission, only biochar amendment had a significant effect. The present study suggests that application of dolomite and biochar to acidic tea field soil can mitigate N2O emissions.

40 CFR 63.4965 - How do I determine the add-on control device emission destruction or removal efficiency?

Code of Federal Regulations, 2010 CFR

2010-07-01

... an alternative to Method 3B, the manual method for measuring the oxygen, carbon dioxide, and carbon..., Instruments and Apparatus]” (incorporated by reference, see § 63.14). (4) Use Method 4 of appendix A to 40 CFR... total gaseous organic mass emissions as carbon at the inlet and outlet of the add-on control device...

40 CFR 63.3545 - How do I determine the add-on control device emission destruction or removal efficiency?

Code of Federal Regulations, 2010 CFR

2010-07-01

... an alternative to Method 3B the manual method for measuring the oxygen, carbon dioxide, and carbon..., Instruments and Apparatus]” (incorporated by reference, see § 63.14). (4) Use Method 4 of appendix A to 40 CFR... total gaseous organic mass emissions as carbon at the inlet and outlet of the add-on control device...

A regional high-resolution emission inventory of primary air pollutants in 2012 for Beijing and the surrounding five provinces of North China

NASA Astrophysics Data System (ADS)

Liu, Huanjia; Wu, Bobo; Liu, Shuhan; Shao, Panyang; Liu, Xiangyang; Zhu, Chuanyong; Wang, Yong; Wu, Yiming; Xue, Yifeng; Gao, Jiajia; Hao, Yan; Tian, Hezhong

2018-05-01

A high resolution regional emission inventory of typical primary air pollutants (PAPs) for the year 2012 in Beijing and the surrounding five provinces (BSFP) of North China is developed. It is compiled with the combination of bottom-up and top-down methods, based on city-level collected activity data and the latest updated specific emission factors for different sources. The considered sources are classified into 12 major categories and totally 36 subcategories with respect to their multi-dimensional characteristics, such as economic sector, combustion facility or industrial process, installed air pollution control devices, etc. Power plant sector is the dominant contributor of NOX emissions with an average contribution of 34.1%, while VOCs emissions are largely emitted from industrial process sources (33.9%). Whereas, other stationary combustion sources represent major sources of primary PM2.5, PM10 and BC emissions, accounting for 22.7%, 30.0% and 33.9% of the total emissions, respectively. Hebei province contributes over 34% of the regional total CO emissions because of huge volume of iron and steel production. By comparison, Shandong province ranks as the biggest contributor for NOX, PM10, PM2.5, SO2, VOCs and OC. Further, the BSFP regional total emissions are spatially distributed into grid cells with a high resolution of 9 km × 9 km using GIS tools and surrogate indexes, such regional population, gross domestic product (GDP) and the types of arable soils. The highest emission intensities are mainly located in Beijing-Tianjin-Tangshan area, Jinan-Laiwu-Zibo area and several other cities such as Shijiazhuang, Handan, and Zhengzhou. Furthermore, in order to establish a simple method to estimate and forecast PAPs emissions with macroscopic provincial-level statistical parameters in China, multi-parameter regression equations are firstly developed to estimate emissions outside the BSFP region with routine statistics (e.g. population, total final coal consumption, area of cultivated land and possession of civil vehicles) using the software 1stOpt. We find the estimated PAPs emissions of 31 provinces show close correlation with the well-recognized MEIC inventory. This high resolution multi-pollutants inventory provides necessary input data for regional air quality models that could help to identify and appoint the major influence sources, better understand the complex regional air pollution formation mechanism, and benefit for developing the corresponding joint prevention and control policies of regional complex air pollution in North China.

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

... Population Emission Factors—Storage Wellheads, Gas Service Connector 0.01 Valve 0.1 Pressure Relief Valve 0.17 Open Ended Line 0.03 Population Emission Factors—Other Components, Gas Service Low Continuous... Bleed Pneumatic Device Vents 2 2.35 1 Valves include control valves, block valves and regulator valves...

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

... Population Emission Factors—Storage Wellheads, Gas Service Connector 0.01 Valve 0.1 Pressure Relief Valve 0.17 Open Ended Line 0.03 Population Emission Factors—Other Components, Gas Service Low Continuous... Bleed Pneumatic Device Vents 2 2.35 1 Valves include control valves, block valves and regulator valves...

40 CFR 63.9307 - What are my continuous emissions monitoring system installation, operation, and maintenance...

Code of Federal Regulations, 2013 CFR

2013-07-01

... install, operate, and maintain each CEMS to monitor carbon monoxide (CO) or total hydrocarbons (THC) and... emission control device. (b) To comply with the CO or THC percent reduction emission limitation, you may install, operate, and maintain a CEMS to monitor CO or THC and O2 at both the inlet and the outlet of the...

40 CFR 63.9307 - What are my continuous emissions monitoring system installation, operation, and maintenance...

Code of Federal Regulations, 2014 CFR

2014-07-01

... install, operate, and maintain each CEMS to monitor carbon monoxide (CO) or total hydrocarbons (THC) and... emission control device. (b) To comply with the CO or THC percent reduction emission limitation, you may install, operate, and maintain a CEMS to monitor CO or THC and O2 at both the inlet and the outlet of the...

40 CFR 63.9307 - What are my continuous emissions monitoring system installation, operation, and maintenance...

Code of Federal Regulations, 2012 CFR

2012-07-01

... install, operate, and maintain each CEMS to monitor carbon monoxide (CO) or total hydrocarbons (THC) and... emission control device. (b) To comply with the CO or THC percent reduction emission limitation, you may install, operate, and maintain a CEMS to monitor CO or THC and O2 at both the inlet and the outlet of the...

40 CFR 63.9307 - What are my continuous emissions monitoring system installation, operation, and maintenance...

Code of Federal Regulations, 2010 CFR

2010-07-01

... install, operate, and maintain each CEMS to monitor carbon monoxide (CO) or total hydrocarbons (THC) and... emission control device. (b) To comply with the CO or THC percent reduction emission limitation, you may install, operate, and maintain a CEMS to monitor CO or THC and O2 at both the inlet and the outlet of the...

40 CFR 63.9307 - What are my continuous emissions monitoring system installation, operation, and maintenance...

Code of Federal Regulations, 2011 CFR

2011-07-01

... install, operate, and maintain each CEMS to monitor carbon monoxide (CO) or total hydrocarbons (THC) and... emission control device. (b) To comply with the CO or THC percent reduction emission limitation, you may install, operate, and maintain a CEMS to monitor CO or THC and O2 at both the inlet and the outlet of the...

40 CFR 63.4761 - How do I demonstrate initial compliance?

Code of Federal Regulations, 2013 CFR

2013-07-01

... HAP emission reduction for the controlled coating operation during the month, grams. Ac = Total mass of organic HAP in the coatings used in the controlled coating operation during the month, grams. Bc..., grams, as calculated in Equation 1B of this section. Cc = Total mass of organic HAP in the cleaning...

40 CFR 63.4761 - How do I demonstrate initial compliance?

Code of Federal Regulations, 2011 CFR

2011-07-01

... HAP emission reduction for the controlled coating operation during the month, grams. Ac = Total mass of organic HAP in the coatings used in the controlled coating operation during the month, grams. Bc..., grams, as calculated in Equation 1B of this section. Cc = Total mass of organic HAP in the cleaning...

40 CFR 63.4761 - How do I demonstrate initial compliance?

Code of Federal Regulations, 2014 CFR

2014-07-01

... HAP emission reduction for the controlled coating operation during the month, grams. Ac = Total mass of organic HAP in the coatings used in the controlled coating operation during the month, grams. Bc..., grams, as calculated in Equation 1B of this section. Cc = Total mass of organic HAP in the cleaning...

40 CFR 63.4761 - How do I demonstrate initial compliance?

Code of Federal Regulations, 2010 CFR

2010-07-01

... HAP emission reduction for the controlled coating operation during the month, grams. Ac = Total mass of organic HAP in the coatings used in the controlled coating operation during the month, grams. Bc..., grams, as calculated in Equation 1B of this section. Cc = Total mass of organic HAP in the cleaning...

40 CFR 63.4761 - How do I demonstrate initial compliance?

Code of Federal Regulations, 2012 CFR

2012-07-01

... HAP emission reduction for the controlled coating operation during the month, grams. Ac = Total mass of organic HAP in the coatings used in the controlled coating operation during the month, grams. Bc..., grams, as calculated in Equation 1B of this section. Cc = Total mass of organic HAP in the cleaning...

Using surface water application to reduce 1,3-dichloropropene emission from soil fumigation.

PubMed

Gao, Suduan; Trout, Thomas J

2006-01-01

High emissions from soil fumigants increase the risk of detrimental impact on workers, bystanders, and the environment, and jeopardize future availability of fumigants. Efficient and cost-effective approaches to minimize emissions are needed. This study evaluated the potential of surface water application (or water seal) to reduce 1,3-dichloropropene (1,3-D) emissions from soil (Hanford sandy loam) columns. Treatments included dry soil (control), initial water application (8 mm of water just before fumigant application), initial plus a second water application (2.6 mm) at 12 h, initial plus two water applications (2.6 mm each time) at 12 and 24 h, standard high density polyethylene (HDPE) tarp, initial water application plus HDPE tarp, and virtually impermeable film (VIF) tarp. Emissions from the soil surface and distribution of 1,3-D in the soil-gas phase were monitored for 2 wk. Each water application abruptly reduced 1,3-D emission flux, which rebounded over a few hours. Peak emission rates were substantially reduced, but total emission reduction was small. Total fumigant emission was 51% of applied for the control, 46% for initial water application only, and 41% for the three intermittent water applications with the remaining water treatment intermediate. The HDPE tarp alone resulted in 45% emission, while initial water application plus HDPE tarp resulted in 38% emission. The most effective soil surface treatment was VIF tarp (10% emission). Surface water application can be as effective, and less expensive than, standard HDPE tarp. Frequent water application is required to substantially reduce emissions.

Methane Emissions from Leak and Loss Audits of Natural Gas Compressor Stations and Storage Facilities.

PubMed

Johnson, Derek R; Covington, April N; Clark, Nigel N

2015-07-07

As part of the Environmental Defense Fund's Barnett Coordinated Campaign, researchers completed leak and loss audits for methane emissions at three natural gas compressor stations and two natural gas storage facilities. Researchers employed microdilution high-volume sampling systems in conjunction with in situ methane analyzers, bag samples, and Fourier transform infrared analyzers for emissions rate quantification. All sites had a combined total methane emissions rate of 94.2 kg/h, yet only 12% of the emissions total resulted from leaks. Methane slip from exhausts represented 44% of the total emissions. Remaining methane emissions were attributed to losses from pneumatic actuators and controls, engine crankcases, compressor packing vents, wet seal vents, and slop tanks. Measured values were compared with those reported in literature. Exhaust methane emissions were lower than emissions factor estimates for engine exhausts, but when combined with crankcase emissions, measured values were 11.4% lower than predicted by AP-42 as applicable to emissions factors for four-stroke, lean-burn engines. Average measured wet seal emissions were 3.5 times higher than GRI values but 14 times lower than those reported by Allen et al. Reciprocating compressor packing vent emissions were 39 times higher than values reported by GRI, but about half of values reported by Allen et al. Though the data set was small, researchers have suggested a method to estimate site-wide emissions factors for those powered by four-stroke, lean-burn engines based on fuel consumption and site throughput.

Intelligent emissions controller for substance injection in the post-primary combustion zone of fossil-fired boilers

DOEpatents

Reifman, Jaques; Feldman, Earl E.; Wei, Thomas Y. C.; Glickert, Roger W.

2003-01-01

The control of emissions from fossil-fired boilers wherein an injection of substances above the primary combustion zone employs multi-layer feedforward artificial neural networks for modeling static nonlinear relationships between the distribution of injected substances into the upper region of the furnace and the emissions exiting the furnace. Multivariable nonlinear constrained optimization algorithms use the mathematical expressions from the artificial neural networks to provide the optimal substance distribution that minimizes emission levels for a given total substance injection rate. Based upon the optimal operating conditions from the optimization algorithms, the incremental substance cost per unit of emissions reduction, and the open-market price per unit of emissions reduction, the intelligent emissions controller allows for the determination of whether it is more cost-effective to achieve additional increments in emission reduction through the injection of additional substance or through the purchase of emission credits on the open market. This is of particular interest to fossil-fired electrical power plant operators. The intelligent emission controller is particularly adapted for determining the economical control of such pollutants as oxides of nitrogen (NO.sub.x) and carbon monoxide (CO) emitted by fossil-fired boilers by the selective introduction of multiple inputs of substances (such as natural gas, ammonia, oil, water-oil emulsion, coal-water slurry and/or urea, and combinations of these substances) above the primary combustion zone of fossil-fired boilers.

Optimizing critical source control of five priority-regulatory trace elements from industrial wastewater in China: Implications for health management.

PubMed

Wu, Wenjun; Wang, Jinnan; Yu, Yang; Jiang, Hongqiang; Liu, Nianlei; Bi, Jun; Liu, Miaomiao

2018-04-01

Anthropogenic emissions of toxic trace elements (TEs) have caused worldwide concern due to their adverse effects on human health and ecosystems. Based on a stochastic simulation of factors' probability distribution, we established a bottom-up model to estimate the amounts of five priority-regulatory TEs released to aquatic environments from industrial processes in China. Total TE emissions in China in 2010 were estimated at approximately 2.27 t of Hg, 310.09 t of As, 318.17 t of Pb, 79.72 t of Cd, and 1040.32 t of Cr. Raw chemicals, smelting, and mining were the leading sources of TE emissions. There are apparent regional differences in TE pollution. TE emissions are much higher in eastern and central China than in the western provinces and are higher in the south than in the north. This spatial distribution was characterized in detail by allocating the emissions to 10 km × 10 km grid cells. Furthermore, the risk control for the overall emission grid was optimized according to each cell's emission and risk rank. The results show that to control 80% of TE emissions from major sources, the number of top-priority control cells would be between 200 and 400, and less than 10% of the total population would be positively affected. Based on TE risk rankings, decreasing the population weighted risk would increase the number of controlled cells by a factor of 0.3-0.5, but the affected population would increase by a factor of 0.8-1.5. In this case, the adverse effects on people's health would be reduced significantly. Finally, an optimized strategy to control TE emissions is proposed in terms of a cost-benefit trade-off. The estimates in this paper can be used to help establish a regional TE inventory and cyclic simulation, and it can also play supporting roles in minimizing TE health risks and maximizing resilience. Copyright © 2018 Elsevier Ltd. All rights reserved.

Spatial and Temporal Trends in Global Emissions of Nitrogen Oxides from 1960 to 2014.

PubMed

Huang, Tianbo; Zhu, Xi; Zhong, Qirui; Yun, Xiao; Meng, Wenjun; Li, Bengang; Ma, Jianmin; Zeng, Eddy Y; Tao, Shu

2017-07-18

The quantification of nitrogen oxide (NO x ) emissions is critical for air quality modeling. Based on updated fuel consumption and emission factor databases, a global emission inventory was compiled with high spatial (0.1° × 0.1°), temporal (monthly), and source (87 sources) resolutions for the period 1960 to 2014. The monthly emission data have been uploaded online ( http://inventory.pku.edu.cn ), along with a number of other air pollutant and greenhouse gas data for free download. Differences in source profiles, not global total quantities, between our results and those reported previously were found. There were significant differences in total and per capita emissions and emission intensities among countries, especially between the developing and developed countries. Globally, the total annual NO x emissions finally stopped increasing in 2013 after continuously increasing over several decades, largely due to strict control measures taken in China in recent years. Nevertheless, the peak year of NO x emissions was later than for many other major air pollutants. Per capita emissions, either among countries or over years, follow typical inverted U-shaped environmental Kuznets curves, indicating that the emissions increased during the early stage of development and were restrained when socioeconomic development reached certain points. Although the trends are similar among countries, the turning points of developing countries appeared sooner than those of developed countries in terms of development status, confirming late-move advantages.

Particulate Emission Abatement for Krakow Boilerhouses

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-09-14

Environmental cleanup and pollution control are considered the foremost national priorities in Poland. The target of this cleanup is the Polish coal industry, which supplies the fuel to generate over 78% of Poland`s primary energy production. This project addresses the problem of airborne dust and uncontrolled particulate emissions from boilerhouses, which represent a large fraction of the total in Poland. In Krakow alone, there are numerous uncontrolled boilers accounting for about half the total fuel use. The large number of low-capacity boilers poses both technical and economic challenges, since the cost of control equipment is a significant factor in themore » reduction of emissions. A new concept in dust collection, called a Core Separator, is proposed for this important application. The Core Separator is an advanced technology developed through research sponsored by the Department of Energy.« less

VOCs emission characteristics and priority control analysis based on VOCs emission inventories and ozone formation potentials in Zhoushan

NASA Astrophysics Data System (ADS)

Wang, Qiaoli; Li, Sujing; Dong, Minli; Li, Wei; Gao, Xiang; Ye, Rongmin; Zhang, Dongxiao

2018-06-01

Zhoushan is an island city with booming tourism and service industry, but also has many developed VOCs and/or NOX emission industries. It is necessary to carry out regional VOCs and O3 pollution control in Zhoushan as the only new area owns the provincial economic and social administration rights. Anthropogenic VOCs emission inventories were built based on emission factor method and main emission sources were identified according to the emission inventories. Then, localized VOCs source profiles were built based on in-site sampling and referring to other studies. Furthermore, ozone formation potentials (OFPs) profiles were built through VOCs source profiles and maximum incremental reactivity (MIR) theory. At last, the priority control analysis results showed that industrial processes, especially surface coating, are the key of VOCs and O3 control. Alkanes were the most emitted group, accounting for 58.67%, while aromatics contributed the most to ozone production accounting for 69.97% in total OFPs. n-butane, m/p-xylene, i-pentane, n-decane, toluene, propane, n-undecane, o-xylene, methyl cyclohexane and ethyl benzene were the top 10 VOC species that should be preferentially controlled for VOCs emission control. However, m/p-xylene, o-xylene, ethylene, n-butane, toluene, propene, 1,2,4-trimethyl benzene, 1,3,5-trimethyl benzene, ethyl benzene and 1,2,3-trimethyl benzene were the top 10 VOC species that required preferential control for O3 pollution control.

Edaphic factors controlling summer (rainy season) greenhouse gas emissions (CO2 and CH4) from semiarid mangrove soils (NE-Brazil).

PubMed

Nóbrega, Gabriel N; Ferreira, Tiago O; Siqueira Neto, M; Queiroz, Hermano M; Artur, Adriana G; Mendonça, Eduardo De S; Silva, Ebenezer De O; Otero, Xosé L

2016-01-15

The soil attributes controlling the CO2, and CH4 emissions were assessed in semiarid mangrove soils (NE-Brazil) under different anthropogenic activities. Soil samples were collected from different mangroves under different anthropogenic impacts, e.g., shrimp farming (Jaguaribe River); urban wastes (Cocó River) and a control site (Timonha River). The sites were characterized according to the sand content; physicochemical parameters (Eh and pH); total organic C; soil C stock (SCS) and equivalent SCS (SCSEQV); total P and N; dissolved organic C (DOC); and the degree of pyritization (DOP). The CO2 and CH4 fluxes from the soils were assessed using static closed chambers. Higher DOC and SCS and the lowest DOP promote greater CO2 emission. The CH4 flux was only observed at Jaguaribe which presented higher DOP, compared to that found in mangroves from humid tropical climates. Semiarid mangrove soils cannot be characterized as important greenhouse gas sources, compared to humid tropical mangroves.

Multi-objective optimisation of wastewater treatment plant control to reduce greenhouse gas emissions.

PubMed

Sweetapple, Christine; Fu, Guangtao; Butler, David

2014-05-15

This study investigates the potential of control strategy optimisation for the reduction of operational greenhouse gas emissions from wastewater treatment in a cost-effective manner, and demonstrates that significant improvements can be realised. A multi-objective evolutionary algorithm, NSGA-II, is used to derive sets of Pareto optimal operational and control parameter values for an activated sludge wastewater treatment plant, with objectives including minimisation of greenhouse gas emissions, operational costs and effluent pollutant concentrations, subject to legislative compliance. Different problem formulations are explored, to identify the most effective approach to emissions reduction, and the sets of optimal solutions enable identification of trade-offs between conflicting objectives. It is found that multi-objective optimisation can facilitate a significant reduction in greenhouse gas emissions without the need for plant redesign or modification of the control strategy layout, but there are trade-offs to consider: most importantly, if operational costs are not to be increased, reduction of greenhouse gas emissions is likely to incur an increase in effluent ammonia and total nitrogen concentrations. Design of control strategies for a high effluent quality and low costs alone is likely to result in an inadvertent increase in greenhouse gas emissions, so it is of key importance that effects on emissions are considered in control strategy development and optimisation. Copyright © 2014 Elsevier Ltd. All rights reserved.

40 CFR 62.2350 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... sulfuric acid production units, submitted on December 14, 1978. (2) Control of total reduced sulfur (TRS... is June 1, 1990. (5) Control of metals, acid gases, organic compounds and nitrogen oxide emissions...

Landfill Methane

USDA-ARS?s Scientific Manuscript database

Landfill methane (CH4) accounts for approximately 1.3% (0.6 Gt) of global anthropogenic greenhouse gas emissions relative to total emissions from all sectors of about 49 Gt CO2-eq yr-1. For countries with a history of controlled landfilling, landfills can be one of the larger national sources of ant...

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

... Connector 5.71 Open-Ended Line 11.27 Pressure Relief Valve 2.01 Meter 2.93 Population Emission Factors—Gas... 18.20 Intermittent Bleed Pneumatic Device Vents 2 2.35 1 Valves include control valves, block valves...

40 CFR 86.1342-94 - Calculations; exhaust emissions.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., if appropriate, the weighted mass total hydrocarbon equivalent, formaldehyde, or non-methane... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED... see § 86.1342-90. (b)(8) Non-methane hydrocarbon mass: NMHCmass = Vmix × DensityNMHC × (NMHCconc/1,000...

40 CFR 86.1342-94 - Calculations; exhaust emissions.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., if appropriate, the weighted mass total hydrocarbon equivalent, formaldehyde, or non-methane... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED... see § 86.1342-90. (b)(8) Non-methane hydrocarbon mass: NMHCmass = Vmix × DensityNMHC × (NMHCconc/1,000...

40 CFR 86.1342-94 - Calculations; exhaust emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., if appropriate, the weighted mass total hydrocarbon equivalent, formaldehyde, or non-methane... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED... see § 86.1342-90. (b)(8) Non-methane hydrocarbon mass: NMHCmass = Vmix × DensityNMHC × (NMHCconc/1,000...

Separate effects of flooding and anaerobiosis on soil greenhouse gas emissions and redox sensitive biogeochemistry

Treesearch

Gavin McNicol; Whendee L. Silver

2014-01-01

Soils are large sources of atmospheric greenhouse gases, and both the magnitude and composition of soil gas emissions are strongly controlled by redox conditions. Though the effect of redox dynamics on greenhouse gas emissions has been well studied in flooded soils, less research has focused on redox dynamics without total soil inundation. For the latter, all that is...

Effects of FAME biodiesel and HVORD on emissions from an older-technology diesel engine.

PubMed

Bugarski, A D; Hummer, J A; Vanderslice, S E

2017-12-01

The results of laboratory evaluations were used to compare the potential of two alternative, biomass-derived fuels as a control strategy to reduce the exposure of underground miners to aerosols and gases emitted by diesel-powered equipment. The effects of fatty acid methyl ester (FAME) biodiesel and hydrotreated vegetable oil renewable diesel (HVORD) on criteria aerosol and gaseous emissions from an older-technology, naturally aspirated, mechanically controlled engine equipped with a diesel oxidation catalytic converter were compared with those of widely used petroleum-derived, ultralow-sulfur diesels (ULSDs). The emissions were characterized for four selected steady-state conditions. When fueled with FAME biodiesel and HVORD, the engine emitted less aerosols by total particulate mass, total carbon mass, elemental carbon mass and total number than when it was fueled with ULSDs. Compared with ULSDs, FAME biodiesel and HVORD produced aerosols that were characterized by single modal distributions, smaller count median diameters, and lower total and peak concentrations. For the majority of test cases, FAME biodiesel and HVORD favorably affected nitric oxide (NO) and adversely affected nitrogen dioxide (NO 2 ) generation. Therefore, the use of these alternative fuels appears to be a viable tool for the underground mining industry to address the issues related to emissions from diesel engines, and to transition toward more universal solutions provided by advanced engines with integrated exhaust after treatment technologies.

Effects of FAME biodiesel and HVORD on emissions from an older-technology diesel engine

PubMed Central

Bugarski, A.D.; Hummer, J.A.; Vanderslice, S.E.

2017-01-01

The results of laboratory evaluations were used to compare the potential of two alternative, biomass-derived fuels as a control strategy to reduce the exposure of underground miners to aerosols and gases emitted by diesel-powered equipment. The effects of fatty acid methyl ester (FAME) biodiesel and hydrotreated vegetable oil renewable diesel (HVORD) on criteria aerosol and gaseous emissions from an older-technology, naturally aspirated, mechanically controlled engine equipped with a diesel oxidation catalytic converter were compared with those of widely used petroleum-derived, ultralow-sulfur diesels (ULSDs). The emissions were characterized for four selected steady-state conditions. When fueled with FAME biodiesel and HVORD, the engine emitted less aerosols by total particulate mass, total carbon mass, elemental carbon mass and total number than when it was fueled with ULSDs. Compared with ULSDs, FAME biodiesel and HVORD produced aerosols that were characterized by single modal distributions, smaller count median diameters, and lower total and peak concentrations. For the majority of test cases, FAME biodiesel and HVORD favorably affected nitric oxide (NO) and adversely affected nitrogen dioxide (NO2) generation. Therefore, the use of these alternative fuels appears to be a viable tool for the underground mining industry to address the issues related to emissions from diesel engines, and to transition toward more universal solutions provided by advanced engines with integrated exhaust after treatment technologies. PMID:29348698

GHGs and air pollutants embodied in China's international trade: Temporal and spatial index decomposition analysis.

PubMed

Liu, Zhengyan; Mao, Xianqiang; Song, Peng

2017-01-01

Temporal index decomposition analysis and spatial index decomposition analysis were applied to understand the driving forces of the emissions embodied in China's exports and net exports during 2002-2011, respectively. The accumulated emissions embodied in exports accounted for approximately 30% of the total emissions in China; although the contribution of the sectoral total emissions intensity (technique effect) declined, the scale effect was largely responsible for the mounting emissions associated with export, and the composition effect played a largely insignificant role. Calculations of the emissions embodied in net exports suggest that China is generally in an environmentally inferior position compared with its major trade partners. The differences in the economy-wide emission intensities between China and its major trade partners were the biggest contribution to this reality, and the trade balance effect played a less important role. However, a lower degree of specialization in pollution intensive products in exports than in imports helped to reduce slightly the emissions embodied in net exports. The temporal index decomposition analysis results suggest that China should take effective measures to optimize export and supply-side structure and reduce the total emissions intensity. According to spatial index decomposition analysis, it is suggested that a more aggressive import policy was useful for curbing domestic and global emissions, and the transfer of advanced production technologies and emission control technologies from developed to developing countries should be a compulsory global environmental policy option to mitigate the possible leakage of pollution emissions caused by international trade.

Decadal evolution of ship emissions in China from 2004 to 2013 by using an integrated AIS-based approach and projection to 2040

NASA Astrophysics Data System (ADS)

Li, Cheng; Borken-Kleefeld, Jens; Zheng, Junyu; Yuan, Zibing; Ou, Jiamin; Li, Yue; Wang, Yanlong; Xu, Yuanqian

2018-05-01

Ship emissions contribute significantly to air pollution and pose health risks to residents of coastal areas in China, but the current research remains incomplete and coarse due to data availability and inaccuracy in estimation methods. In this study, an integrated approach based on the Automatic Identification System (AIS) was developed to address this problem. This approach utilized detailed information from AIS and cargo turnover and the vessel calling number information and is thereby capable of quantifying sectoral contributions by fuel types and emissions from ports, rivers, coastal traffic and over-the-horizon ship traffic. Based upon the established methodology, ship emissions in China from 2004 to 2013 were estimated, and those to 2040 at 5-year intervals under different control scenarios were projected. Results showed that for the area within 200 nautical miles (Nm) of the Chinese coast, SO2, NOx, CO, PM10, PM2.5, hydrocarbon (HC), black carbon (BC) and organic carbon (OC) emissions in 2013 were 1010, 1443, 118, 107, 87, 67, 29 and 21 kt yr-1, respectively, which doubled over these 10 years. Ship sources contributed ˜ 10 % to the total SO2 and NOx emissions in the coastal provinces of China. Emissions from the proposed Domestic Emission Control Areas (DECAs) within 12 Nm constituted approximately 40 % of the all ship emissions along the Chinese coast, and this percentage would double when the DECA boundary is extended to 100 Nm. Ship emissions in ports accounted for about one-quarter of the total emissions within 200 Nm, within which nearly 80 % of the emissions were concentrated in the top 10 busiest ports of China. SO2 emissions could be reduced by 80 % in 2020 under a 0.5 % global sulfur cap policy. In comparison, a similar reduction of NOx emissions would require significant technological change and would likely take several decades. This study provides solid scientific support for ship emissions control policy making in China. It is suggested to investigate and monitor the emissions from the shipping sector in more detail in the future.

Assessing the co-benefits of greenhouse gas reduction: health benefits of particulate matter related inspection and maintenance programs in Bangkok, Thailand.

PubMed

Li, Ying; Crawford-Brown, Douglas J

2011-04-15

Since the 1990s, the capital city of Thailand, Bangkok has been suffering from severe ambient particulate matter (PM) pollution mainly attributable to its wide use of diesel-fueled vehicles and motorcycles with poor emission performance. While the Thai government strives to reduce emissions from transportation through enforcing policy measures, the link between specific control policies and associated health impacts is inadequately studied. This link is especially important in exploring the co-benefits of greenhouse gas emissions reductions, which often brings reduction in other pollutants such as PM. This paper quantifies the health benefits potentially achieved by the new PM-related I/M programs targeting all diesel vehicles and motorcycles in the Bangkok Metropolitan Area (BMA). The benefits are estimated by using a framework that integrates policy scenario development, exposure assessment, exposure-response assessment and economic valuation. The results indicate that the total health damage due to the year 2000 PM emissions from vehicles in the BMA was equivalent to 2.4% of Thailand's GDP. Under the business-as-usual (BAU) scenario, total vehicular PM emissions in the BMA will increase considerably over time due to the rapid growth in vehicle population, even if the fleet average emission rates are projected to decrease over time as the result of participation of Thailand in post-Copenhagen climate change strategies. By 2015, the total health damage is estimated to increase by 2.5 times relative to the year 2000. However, control policies targeting PM emissions from automobiles, such as the PM-oriented I/M programs, could yield substantial health benefits relative to the BAU scenario, and serve as co-benefits of greenhouse gas control strategies. Despite uncertainty associated with the key assumptions used to estimate benefits, we find that with a high level confidence, the I/M programs will produce health benefits whose economic impacts considerably outweigh the expenditures on policy implementation. Copyright © 2011 Elsevier B.V. All rights reserved.

Emission Controls Versus Meteorological Conditions in Determining Aerosol Concentrations in Beijing during the 2008 Olympic Games

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Yi; Liu, Xiaohong; Zhao, Chun

A series of emission control measures were undertaken in Beijing and the adjacent provinces in China during the 2008 Beijing Olympic Games on August 8th-24th, 2008. This provides a unique opportunity for investigating the effectiveness of emission controls on air pollution in Beijing. We conducted a series of numerical experiments over East Asia for the period of July to September 2008 using a coupled meteorology-chemistry model (WRF-Chem). Model can generally reproduce the observed variation of aerosol concentrations. Consistent with observations, modeled concentrations of aerosol species (sulfate, nitrate, ammonium, black carbon, organic carbon, total particulate matter) in Beijing were decreased bymore » 30-50% during the Olympic period compared to the other periods in July and August in 2008 and the same period in 2007. Model results indicate that emission controls were effective in reducing the aerosol concentrations by comparing simulations with and without emission controls. However, our analysis suggests that meteorological conditions (e.g., wind direction and precipitation) are at least as important as emission controls in producing the low aerosol concentrations appearing during the Olympic period. Transport from the regions surrounding Beijing determines the temporal variation of aerosol concentrations in Beijing. Based on the budget analysis, we suggest that emission control strategy should focus on the regional scale instead of the local scale to improve the air quality over Beijing.« less

High-resolution forest carbon stocks and emissions in the Amazon.

PubMed

Asner, Gregory P; Powell, George V N; Mascaro, Joseph; Knapp, David E; Clark, John K; Jacobson, James; Kennedy-Bowdoin, Ty; Balaji, Aravindh; Paez-Acosta, Guayana; Victoria, Eloy; Secada, Laura; Valqui, Michael; Hughes, R Flint

2010-09-21

Efforts to mitigate climate change through the Reduced Emissions from Deforestation and Degradation (REDD) depend on mapping and monitoring of tropical forest carbon stocks and emissions over large geographic areas. With a new integrated use of satellite imaging, airborne light detection and ranging, and field plots, we mapped aboveground carbon stocks and emissions at 0.1-ha resolution over 4.3 million ha of the Peruvian Amazon, an area twice that of all forests in Costa Rica, to reveal the determinants of forest carbon density and to demonstrate the feasibility of mapping carbon emissions for REDD. We discovered previously unknown variation in carbon storage at multiple scales based on geologic substrate and forest type. From 1999 to 2009, emissions from land use totaled 1.1% of the standing carbon throughout the region. Forest degradation, such as from selective logging, increased regional carbon emissions by 47% over deforestation alone, and secondary regrowth provided an 18% offset against total gross emissions. Very high-resolution monitoring reduces uncertainty in carbon emissions for REDD programs while uncovering fundamental environmental controls on forest carbon storage and their interactions with land-use change.

Atmospheric toxic metals emission inventory and spatial characteristics from anthropogenic sources of Guangdong province, China

NASA Astrophysics Data System (ADS)

Cher, S.; Menghua, L.; Xiao, X.; Yuqi, W.; Zhuangmin, Z.; Zhijiong, H.; Cheng, L.; Guanglin, J.; Zibing, Y.; Junyu, Z.

2017-12-01

Atmospheric toxic metals (TMs) are part of particulate matters, and may create adverse effects on the environment and human health depending upon their bioavailability and toxicity. Localized emission inventory is fundamental for parsing of toxic metals to identify key sources in order to formulate efficient toxic metals control strategies. With the use of the latest municipal level environment statistical data, this study developed a bottom-up emission inventory of five toxic metals (Hg, As, Pb, Cd, Cr) from anthropogenic activities in Guangdong province for the year of 2014. Major atmospheric toxic metals sources including combustion sources (coal, oil, biomass, municipal solid waste) and industrial process sources (cement production, nonferrous metal smelting, iron and steel industry, battery and fluorescent lamp production) were investigated. Results showed that: (1) The total emissions of Hg, As, Pb, Cd, Cr in Guangdong province were 18.14, 32.59, 411.34, 13.13, 84.16 t, respectively. (2) Different pollutants have obvious characteristics of emission sources. For total Hg emission, 46% comes from combustion sources, of which 32% from coal combustion and 8% from MSW combustion. Other 54% comes from industrial processes, which dominated by the cement (19%), fluorescent lamp (18%) and battery production (13%). Of the total Hg emission, 69% is released as Hg0 , 29% as Hg2+ , and only 2% as Hgp due to strict particulate matters controls policies. For As emissions, coal combustion, nonferrous metal smelting and iron and steel industry contributed approximate 48%, 25% and 24%, respectively. Pb emissions primarily come from battery production (42%), iron and steel industry (21%) and on-road mobile gasoline combustion (17%). Cd and Cr emissions were dominated by nonferrous metal smelting (71%) and iron and steel industry (82%), respectively. (3) In term of the spatial distribution, emissions of atmospheric toxic metals are mainly concentrated in the central region of the Pearl River Delta, such as, Guangzhou, Dongguan, and Foshan et.al. These areas were characterized with large amounts of coal combustion, battery production and fluorescent production. With the implementation of ultra-low emission standards in coal-fired power plant, TMs emissions from industrial process sources should be emphasized.

Emissions of polycyclic aromatic hydrocarbons from batch hot mix asphalt plants.

PubMed

Lee, Wen-Jhy; Chao, Wen-Hui; Shih, Minliang; Tsai, Cheng-Hsien; Chen, Thomas Jeng-Ho; Tsai, Perng-Jy

2004-10-15

This study was set out to assess the characteristics of polycyclic aromatic hydrocarbon (PAH) emissions from batch hot mix asphalt (HMA) plants and PAH removal efficiencies associated with their installed air pollution control devices. Field samplings were conducted on six randomly selected batch HMA plants. For each selected plant, stack flue gas samples were collected from both stacks of the batch mixer (n = 5) and the preheating boiler (n = 5), respectively. PAH samples were also collected from the field to assess PAHs that were directly emitted from the discharging chute (n = 3). To assess PAH removal efficiencies of the installed air pollution control devices, PAH contents in both cyclone fly ash (n=3) and bag filter fly ash (n = 3) were analyzed. Results show that the total PAH concentration (mean; RSD) in the stack flue gas of the batch mixer (354 microg/Nm3; 78.5%) was higher than that emitted from the discharging chute (107 microg/Nm3; 70.1%) and that in the stack flue gas of the preheating boiler (83.7 microg/Nm3; 77.6%). But the total BaPeq concentration of that emitted from the discharging chute (0.950 microg/Nm3; 84.4%) was higher than contained in the stack flue gas of the batch mixer (0.629 microg/Nm3; 86.8%) and the stack flue gas of the preheating boiler (= 0.112 microg/Nm3; 80.3%). The mean total PAH emission factor for all selected batch mix plants (= 139 mg/ton x product) was much higher than that reported by U.S. EPA for the drum mix asphalt plant (range = 11.8-79.0 mg/ton x product). We found the overall removal efficiency of the installed air pollution control devices (i.e., cyclone + bag filter) on total PAHs and total BaPeq were 22.1% and 93.7%, respectively. This implies that the installed air pollution control devices, although they have a very limited effect on the removal of total PAHs, do significantly reduce the carcinogenic potencies associated with PAH emissions from batch HMA plants.

[VOCs tax policy on China's economy development].

PubMed

Liu, Chang-Xin; Wang, Yu-Fei; Wang, Hai-Lin; Hao, Zheng-Ping; Wang, Zheng

2011-12-01

In this paper, environmental tax was designed to control volatile organic compounds (VOCs) emissions. Computable general equilibrium (CGE) model was used to explore the impacts of environmental tax (in forms of indirect tax) on the macro-economy development at both national and sector levels. Different levels of tax were simulated to find out the proper tax rate. It is found out that imposing environmental tax on high emission sectors can cause the emission decreased immediately and can lead to negative impacts on macro-economy indicators, such as GDP (gross domestic products), total investment, total product and the whole consumption etc. However, only the government income increased. In addition, the higher the tax rate is, the more pollutants can be reduced and the worse economic effects can be caused. Consequently, it is suggested that, the main controlling policies of VOCs abatement should be mandatory orders, and low environmental tax can be implemented as a supplementary.

Evaluation of diesel fleet emissions and control policies from plume chasing measurements of on-road vehicles

NASA Astrophysics Data System (ADS)

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

2015-12-01

Vehicle emissions are an important source of urban air pollution. Diesel fuelled vehicles, although constituting a relatively small fraction of fleet population in many cities, are significant contributors to the emission inventory due to their often long mileage for goods and public transport. Recent classification of diesel exhaust as carcinogenic by the World Health Organization also raises attention to more stringent control of diesel emissions to protect public health. Although various mandatory and voluntary based emission control measures have been implemented in Hong Kong, there have been few investigations to evaluate if the fleet emission characteristics have met desired emission reduction objectives and if adoption of an Inspection/Maintenance (I/M) programme has been effective in achieving these objectives. The limitations are partially due to the lack of cost-effective approaches for the large scale characterisation of fleet based emissions to assess the effectiveness of control measures and policy. This study has used a plume chasing method to collect a large amount of on-road vehicle emission data of Hong Kong highways and a detailed analysis was carried out to provide a quantitative evaluation of the emission characteristics in terms of the role of high and super-emitters in total emission reduction, impact of after-treatment on the multi-pollutants reduction strategy and the trend of NO2 emissions with newer emission standards. The study revealed that not all the high-emitters are from those vehicles of older Euro emission standards. Meanwhile, there is clear evidence that high-emitters for one pollutant may not be a high-emitter for another pollutant. Multi-pollutant control strategy needs to be considered in the enactment of the emission control policy which requires more comprehensive retrofitting technological solutions and matching I/M programme to ensure the proper maintenance of fleets. The plume chasing approach used in this study also shows to be a useful approach for assessing city wide vehicle emission characteristics.

Tuning Fluorescence Direction with Plasmonic Metal–Dielectric– Metal Substrates

PubMed Central

Choudhury, Sharmistha Dutta; Badugu, Ramachandram; Nowaczyk, Kazimierz; Ray, Krishanu; Lakowicz, Joseph R.

2013-01-01

Controlling the emission properties of fluorophores is essential for improving the performance of fluorescence-based techniques in modern biochemical research, medical diagnosis, and sensing. Fluorescence emission is isotropic in nature, which makes it difficult to capture more than a small fraction of the total emission. Metal– dielectric–metal (MDM) substrates, discussed in this Letter, convert isotropic fluorescence into beaming emission normal to the substrate. This improves fluorescence collection efficiency and also opens up new avenues for a wide range of fluorescence-based applications. We suggest that MDM substrates can be readily adapted for multiple uses, such as in microarray formats, for directional fluorescence studies of multiple probes or for molecule-specific sensing with a high degree of spatial control over the fluorescence emission. SECTION: Physical Processes in Nanomaterials and Nanostructures PMID:24013521

Numerical analysis of lateral illumination lightpipes using elliptical grooves

NASA Astrophysics Data System (ADS)

Sánchez-Guerrero, Guillermo E.; Viera-González, Perla M.; Martínez-Guerra, Edgar; Ceballos-Herrera, Daniel E.

2017-09-01

Lightpipes are used for illumination in applications such as back-lighting or solar cell concentrators due to the high irradiance uniformity, but its optimal design requires several parameters. This work presents a procedure to design a square lightpipe to control the light-extraction on its lateral face using commercial LEDs placed symmetrically in the lightpipe frontal face. We propose the use of grooves using total internal reflection placed successively in the same face of extraction to control the area of emission. The LED area of emission is small compared with the illuminated area, and, as expected, the lateral face total power is attenuated. These grooves reduce the optical elements in the system and can control areas of illumination. A mathematical and numerical analysis are presented to determine the dependencies on the light-extraction.

40 CFR 1065.1001 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-control system means any device, system, or element of design that controls or reduces the emissions of... of 1.85:1. Total hydrocarbon equivalent (THCE) means the sum of the carbon mass contributions of non....1001 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS...

40 CFR 1065.1001 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-control system means any device, system, or element of design that controls or reduces the emissions of... of 1.85:1. Total hydrocarbon equivalent (THCE) means the sum of the carbon mass contributions of non....1001 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS...

Characteristics of polycyclic aromatic hydrocarbons and their gas/particle partitioning from fugitive emissions in coke plants

NASA Astrophysics Data System (ADS)

Mu, Ling; Peng, Lin; Liu, Xiaofeng; Song, Chongfang; Bai, Huiling; Zhang, Jianqiang; Hu, Dongmei; He, Qiusheng; Li, Fan

2014-02-01

Coking is one of the most important emission sources of polycyclic aromatic hydrocarbons (PAHs) in China. However, there is little information available on the emission characteristics of PAHs from fugitive emission during coking, especially on the specific processes dominating the gas-particle partitioning of PAHs. In this study, emission characteristics and gas-particle partitioning of PAHs from fugitive emission in four typical coke plants (CPs) with different scales and techniques were investigated. The average concentrations of total PAHs from fugitive emission at CP2, CP3 and CP4 (stamp charging) were 146.98, 31.82, and 35.20 μg m-3, which were 13.38-, 2.90- and 3.20-fold higher, respectively, than those at CP1 (top charging, 10.98 μg m-3). Low molecular weight PAHs with 2-3 rings made up 75.3% of the total PAHs on average, and the contributions of particulate PAH to the total BaP equivalent concentrations (BaPeq) in each plant were significantly higher than the corresponding contributions to the total PAH mass concentrations. The calculated total BaPeq concentrations varied from 0.19 to 10.86 μg m-3 with an average of 3.14 μg m-3, and more efficient measures to control fugitive emission in coke plants should be employed to prevent or reduce the health risk to workers. Absorption into organic matter dominated the gas-particle partitioning for most of the PAHs including PhA, FluA, Chr, BbF, BkF and BaP, while adsorption on elemental carbon appeared to play a dominant role for AcPy, AcP and Flu.

Health impact assessment of ambient fine particulate matter exposure in impacts by different vehicle control measures in China

NASA Astrophysics Data System (ADS)

LI, S.; Wang, H.; Jiang, F.; Zhang, S.

2017-12-01

Road transportation is the one of the largest emission sources contributing to ambient PM2.5 pollution in China. Since the 1990s, China has adopted comprehensive control measures to mitigate vehicle emissions. However, the effects of these measures on reducing emissions, improving air quality and avoiding negative health impacts have not been systematically evaluated. In this study, we combine emissions inventory, air quality modeling, and IER model to evaluate the effect of various vehicle control measures on premature deaths attributable to ambient PM2.5 at a spatial resolution of 36 km × 36 km across China. Our results show that, comparing to no control scenarios, the total vehicular emissions with the actual vehicle emission controls implemented have reduced the emissions of NOX, HC, CO, PM2.5 by 57%, 69%, 75%, 71% respectively; and reduced the national annual mean PM2.5 concentration by 2.5ug/m³ across China by 2010. The number of avoidable deaths associated with reducing PM2.5 level is 150 thousands (95% Confidence interval: 66 thousand - 212 thousand). The geographic distribution of the absolute number of avoidable deaths presents a distinct regional feature and is particularly evident in several regions. The most influential areas are mainly concentrated in Beijing and its south part, which formed a large area of continuous high value. Our results have important policy implications on prioritizing vehicular emission control strategy in China.

Temporal trends and spatial variation characteristics of primary air pollutants emissions from coal-fired industrial boilers in Beijing, China.

PubMed

Xue, Yifeng; Tian, Hezhong; Yan, Jing; Zhou, Zhen; Wang, Junling; Nie, Lei; Pan, Tao; Zhou, Junrui; Hua, Shenbing; Wang, Yong; Wu, Xiaoqing

2016-06-01

Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007-2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM10, PM2.5, SO2, NOx, CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NOx and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Effects of diurnal warming on soil N2O emission in soybean field].

PubMed

Hu, Zheng-Hua; Zhou, Ying-Ping; Cui, Hai-Ling; Chen, Shu-Tao; Xiao, Qi-Tao; Liu, Yan

2013-08-01

To investigate the impact of experimental warming on N2O emission from soil of soybean field, outdoor experiments with simulating diurnal warming were conducted, and static dark chamber-gas chromatograph method was used to measure N2O emission fluxes. Results indicated that: the diurnal warming did not change the seasonal pattern of N2O emissions from soil. In the whole growing season, comparing to the control treatment (CK), the warming treatment (T) significantly enhanced the N2O flux and the cumulative amount of N2O by 17.31% (P = 0.019), and 20.27% (P = 0.005), respectively. The significant correlations were found between soil N2O emission and soil temperature, moisture. The temperature sensitivity values of soil N2O emission under CK and T treatments were 3.75 and 4.10, respectively. In whole growing stage, T treatment significantly increased the crop aboveground and total biomass, the nitrate reductase activity, and total nitrogen in leaves, while significantly decreased NO3(-) -N content in leaves. T treatment significantly increased soil NO3(-) -N content, but had no significant effect on soil organic carbon and total nitrogen contents. The results of this study suggested that diurnal warming enhanced N2O emission from soil in soybean field.

GHGs and air pollutants embodied in China’s international trade: Temporal and spatial index decomposition analysis

PubMed Central

Liu, Zhengyan; Mao, Xianqiang; Song, Peng

2017-01-01

Temporal index decomposition analysis and spatial index decomposition analysis were applied to understand the driving forces of the emissions embodied in China’s exports and net exports during 2002–2011, respectively. The accumulated emissions embodied in exports accounted for approximately 30% of the total emissions in China; although the contribution of the sectoral total emissions intensity (technique effect) declined, the scale effect was largely responsible for the mounting emissions associated with export, and the composition effect played a largely insignificant role. Calculations of the emissions embodied in net exports suggest that China is generally in an environmentally inferior position compared with its major trade partners. The differences in the economy-wide emission intensities between China and its major trade partners were the biggest contribution to this reality, and the trade balance effect played a less important role. However, a lower degree of specialization in pollution intensive products in exports than in imports helped to reduce slightly the emissions embodied in net exports. The temporal index decomposition analysis results suggest that China should take effective measures to optimize export and supply-side structure and reduce the total emissions intensity. According to spatial index decomposition analysis, it is suggested that a more aggressive import policy was useful for curbing domestic and global emissions, and the transfer of advanced production technologies and emission control technologies from developed to developing countries should be a compulsory global environmental policy option to mitigate the possible leakage of pollution emissions caused by international trade. PMID:28441399

40 CFR 63.420 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

...-CE)+0.17 (TE)+0.08(TES)+0.038(TI)+8.5×10-6(C)+KQ]+0.04(OE) where: ET = emissions screening factor for... efficiency limitation on potential to emit for the vapor processing system used to control emissions from... of external floating roof gasoline storage vessels with only primary seals; TES = total number of...

40 CFR 63.420 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

...-CE)+0.17 (TE)+0.08(TES)+0.038(TI)+8.5×10-6(C)+KQ]+0.04(OE) where: ET = emissions screening factor for... efficiency limitation on potential to emit for the vapor processing system used to control emissions from... of external floating roof gasoline storage vessels with only primary seals; TES = total number of...

40 CFR 63.420 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

...-CE)+0.17 (TE)+0.08(TES)+0.038(TI)+8.5×10-6(C)+KQ]+0.04(OE) where: ET = emissions screening factor for... efficiency limitation on potential to emit for the vapor processing system used to control emissions from... of external floating roof gasoline storage vessels with only primary seals; TES = total number of...

40 CFR 63.420 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

...-CE)+0.17 (TE)+0.08(TES)+0.038(TI)+8.5×10-6(C)+KQ]+0.04(OE) where: ET = emissions screening factor for... efficiency limitation on potential to emit for the vapor processing system used to control emissions from... of external floating roof gasoline storage vessels with only primary seals; TES = total number of...

40 CFR 63.420 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-07-01

...)(1-CE)+0.17 (TE)+0.08(TES)+0.038(TI)+8.5×10-6(C)+KQ]+0.04(OE) where: ET = emissions screening factor... efficiency limitation on potential to emit for the vapor processing system used to control emissions from... of external floating roof gasoline storage vessels with only primary seals; TES = total number of...

Observations and models of emissions of volatile terpenoid compounds from needles of ponderosa pine trees growing in situ: control by light, temperature and stomatal conductance.

PubMed

Harley, Peter; Eller, Allyson; Guenther, Alex; Monson, Russell K

2014-09-01

Terpenoid emissions from ponderosa pine (Pinus ponderosa subsp. scopulorum) were measured in Colorado, USA over two growing seasons to evaluate the role of incident light, needle temperature, and stomatal conductance in controlling emissions of 2-methyl-3-buten-2-ol (MBO) and several monoterpenes. MBO was the dominant daylight terpenoid emission, comprising on average 87% of the total flux, and diurnal variations were largely determined by light and temperature. During daytime, oxygenated monoterpenes (especially linalool) comprised up to 75% of the total monoterpenoid flux from needles. A significant fraction of monoterpenoid emissions was dependent on light and 13CO2 labeling studies confirmed de novo production. Thus, modeling of monoterpenoid emissions required a hybrid model in which a significant fraction of emissions was dependent on both light and temperature, while the remainder was dependent on temperature alone. Experiments in which stomata were forced to close using abscisic acid demonstrated that MBO and a large fraction of the monoterpene flux, presumably linalool, could be limited at the scale of seconds to minutes by stomatal conductance. Using a previously published model of terpenoid emissions, which explicitly accounts for the physicochemical properties of emitted compounds, we were able to simulate these observed stomatal effects, whether induced experimentally or arising under naturally fluctuation conditions of temperature and light. This study shows unequivocally that, under naturally occurring field conditions, de novo light-dependent monoterpenes comprise a significant fraction of emissions in ponderosa pine. Differences between the monoterpene composition of ambient air and needle emissions imply a significant non-needle emission source enriched in Δ-3-carene.

Controls on boreal peat combustion and resulting emissions of carbon and mercury

NASA Astrophysics Data System (ADS)

Kohlenberg, Andrew J.; Turetsky, Merritt R.; Thompson, Dan K.; Branfireun, Brian A.; Mitchell, Carl P. J.

2018-03-01

Warming in the boreal forest region has already led to changes in the fire regime. This may result in increasing fire frequency or severity in peatlands, which could cause these ecosystems to shift from a net sink of carbon (C) to a net source of C to the atmosphere. Similar to C cycling, peatlands serve as a net sink for mercury (Hg), which binds strongly to organic matter and accumulates in peat over time. This stored Hg is also susceptible to re-release to the atmosphere during peat fires. Here we investigate the physical properties that influence depth of burn in experimental peat columns and the resulting emissions of CO, CO2, CH4, and gaseous and particulate Hg. As expected, bulk density and soil moisture content were important controls on depth of burn, CO2 emissions, and CO emissions. However, our results show that CH4 and Hg emissions are insensitive to combustion temperature or fuel moisture content. Emissions during the burning of peat, across a wide range of moisture conditions, were associated with low particulate Hg and high gaseous Hg release. Due to strong correlations between total Hg and CO emissions and because high Hg emissions occurred despite incomplete combustion of total C, our results suggest that Hg release during peat burning is governed by the thermodynamics of Hg reduction more so than by the release of Hg associated with peat combustion. Our measured emissions ratios, particularly for CH4:CO2, are higher than values typically used in the upscaling of boreal forest or peatland fire emissions. These emission ratios have important implications not only for our understanding of smouldering chemistry, but also for potential influences of peat fires on the Earth’s climate system.

Quantitative assessment of industrial VOC emissions in China: Historical trend, spatial distribution, uncertainties, and projection

NASA Astrophysics Data System (ADS)

Zheng, Chenghang; Shen, Jiali; Zhang, Yongxin; Huang, Weiwei; Zhu, Xinbo; Wu, Xuecheng; Chen, Linghong; Gao, Xiang; Cen, Kefa

2017-02-01

The temporal trends of industrial volatile organic compound (VOC) emissions was comprehensively summarized for the 2011 to 2013 period, and the projections for 2020 to 2050 for China were set. The results demonstrate that industrial VOC emissions in China increased from 15.3 Tg in 2011 to 29.4 Tg in 2013 at an annual average growth rate of 38.3%. Guangdong (3.45 Tg), Shandong (2.85 Tg), and Jiangsu (2.62 Tg) were the three largest contributors collectively accounting for 30.4% of the national total emissions in 2013. The top three average industrial VOC emissions per square kilometer were Shanghai (247.2 ton/km2), Tianjin (62.8 ton/km2), and Beijing (38.4 ton/km2), which were 12-80 times of the average level in China. The data from the inventory indicate that the use of VOC-containing products, as well as the production and use of VOCs as raw materials, as well as for storage and transportation contributed 75.4%, 10.3%, 9.1%, and 5.2% of the total emissions, respectively. ArcGIS was used to display the remarkable spatial distribution variation by allocating the emission into 1 km × 1 km grid cells with a population as surrogate indexes. Combined with future economic development and population change, as well as implementation of policy and upgrade of control technologies, three scenarios (scenarios A, B, and C) were set to project industrial VOC emissions for the years 2020, 2030, and 2050, which present the industrial VOC emissions in different scenarios and the potential of reducing emissions. Finally, the result shows that the collaborative control policies considerably influenced industrial VOC emissions.

Observations and models of emissions of volatile terpenoid compounds from needles of ponderosa pine trees growing in situ: control by light, temperature and stomatal conductance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harley, Peter; Eller, Allyson; Guenther, Alex

Terpenoid emissions from ponderosa pine (Pinus ponderosa subsp. scopulorum) were measured in Colorado, USA over two growing seasons to evaluate the role of incident light, needle temperature and stomatal conductance in controlling emissions of 2-methyl-3-buten-2-ol (MBO) and several monoterpenes. MBO was the dominant daylight terpenoid emission, comprising on average 87% of the total flux, and diurnal variations were largely determined by light and temperature. During daytime, oxygenated monoterpenes (especially linalool) comprised up to 75% of the total monoterpenoid flux from needles. A significant fraction of monoterpenoid emissions was light dependent and 13CO2 labeling studies confirmed de novo production. Thus, modelingmore » of monoterpenoid emissions required a hybrid model in which a significant fraction of emissions was dependent on both light and temperature, while the remainder was dependent on temperature alone. Experiments in which stomata were forced to close using abscisic acid demonstrated that MBO and a large fraction of the monoterpene flux, presumably linalool, could be limited at the scale of seconds to minutes by stomatal conductance. Using a previously published model of terpenoid emissions which explicitly accounts for the physico-chemical properties of emitted compounds, we are able to simulate these observed stomatal effects, whether induced through experimentation or arising under naturally fluctuation conditions of temperature and light. This study shows unequivocally that, under naturally occurring field conditions, de novo light dependent monoterpenes can comprise a large fraction of emissions. Differences between the monoterpene composition of ambient air and needle emissions imply a significant non-needle emission source enriched in Δ-3-carene.« less

Total sulfur dioxide emissions and pre-eruption vapor-saturated magma at Mount St. Helens, 1980-88

NASA Astrophysics Data System (ADS)

Gerlach, T. M.; McGee, K. A.

1994-12-01

SO2 from explosive volcanism can cause significant climatic and atmospheric impacts, but the source of the sulfur is controversial. Total ozone mapping spectrometer (TOMS), correlation spectrometer (COSPEC), and ash leachate data for Mount St. Helens from the time of the climactic eruption on 18 May 1980 to the final stages of non-explosive degassing in 1988 give a total SO2 emission of 2 Mt. COSPEC data show a sharp drop in emission rate that was apparently controlled by a decreasing rate of magma supply. A total SO2 emission of only 0.08 Mt is estimated from melt inclusion data and the conventional assumption that the main sulfur source was pre-eruption melt; commonly invoked sources of 'excess sulfur' (anhydrite decomposition, basaltic magma, and degassing of non-erupted magma) are unlikely in this case. Thus melt inclusions may significantly underestimate SO2 emissions and impacts of explosive volcanism on climate and the atmosphere. Measured CO2 emissions, together with the H2O content of melt inclusions and experimental solubility data, indicate the Mount St. Helens dacite was vapor-saturated at depth prior to ascent and suggest that a vapor phase was the main source of sulfur for the 2-Mt of SO2. A vapor source is consistent with experimental studies on the Mount St. Helens dacite and removes the need for a much debated shallow magma body.

Computer-oriented emissions inventory procedure for urban and industrial sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Runca, E.; Zannetti, P.; Melli, P.

1978-06-01

A knowledge of the rate of emission of atmospheric pollutants is essential for the enforcement of air quality control policies. A computer-oriented emission inventory procedure has been developed and applied to Venice, Italy. By using optically readable forms this procedure avoids many of the errors inherent in the transcription and punching steps typical of approaches applied so far. Moreover, this procedure allows an easy updating of the inventory. Emission patterns of SO/sub 2/ in the area of Venice showed that the total urban emissions were about 6% of those emitted by industrial sources.

Seasonal soil VOC exchange rates in a Mediterranean holm oak forest and their responses to drought conditions

NASA Astrophysics Data System (ADS)

Asensio, Dolores; Peñuelas, Josep; Ogaya, Romà; Llusià, Joan

Available information on soil volatile organic compound (VOC) exchange, emissions and uptake, is very scarce. We here describe the amounts and seasonality of soil VOC exchange during a year in a natural Mediterranean holm oak forest growing in Southern Catalonia. We investigated changes in soil VOC dynamics in drought conditions by decreasing the soil moisture to 30% of ambient conditions by artificially excluding rainfall and water runoff, and predicted the response of VOC exchange to the drought forecasted in the Mediterranean region for the next decades by GCM and ecophysiological models. The annual average of the total (detected) soil VOC and total monoterpene exchange rates were 3.2±3.2 and -0.4±0.3 μg m -2 h -1, respectively, in control plots. These values represent 0.003% of the total C emitted by soil at the study site as CO 2 whereas the annual mean of soil monoterpene exchange represents 0.0004% of total C. Total soil VOC exchange rates in control plots showed seasonal variations following changes in soil moisture and phenology. Maximum values were found in spring (17±8 μg m -2 h -1). Although there was no significant global effect of drought treatment on the total soil VOC exchange rates, annual average of total VOC exchange rates in drought plots resulted in an uptake rate (-0.5±1.8 μg m -2 h -1) instead of positive net emission rates. Larger soil VOC and monoterpene exchanges were measured in drought plots than in control plots in summer, which might be mostly attributable to autotrophic (roots) metabolism. The results show that the diversity and magnitude of monoterpene and VOC soil emissions are low compared with plant emissions, that they are driven by soil moisture, that they represent a very small part of the soil-released carbon and that they may be strongly reduced or even reversed into net uptakes by the predicted decreases of soil water availability in the next decades. In all cases, it seems that VOC fluxes in soil might have greater impact on soil ecology than on atmospheric chemistry.

Ozone-induced foliar damage and release of stress volatiles is highly dependent on stomatal openness and priming by low-level ozone exposure in Phaseolus vulgaris.

PubMed

Li, Shuai; Harley, Peter C; Niinemets, Ülo

2017-09-01

Acute ozone exposure triggers major emissions of volatile organic compounds (VOCs), but quantitatively, it is unclear how different ozone doses alter the start and the total amount of these emissions, and the induction rate of different stress volatiles. It is also unclear whether priming (i.e. pre-exposure to lower O 3 concentrations) can modify the magnitude and kinetics of volatile emissions. We investigated photosynthetic characteristics and VOC emissions in Phaseolus vulgaris following acute ozone exposure (600 nmol mol -1 for 30 min) under illumination and in darkness and after priming with 200 nmol mol -1 O 3 for 30 min. Methanol and lipoxygenase (LOX) pathway product emissions were induced rapidly, followed by moderate emissions of methyl salicylate (MeSA). Stomatal conductance prior to acute exposure was lower in darkness and after low O 3 priming than in light and without priming. After low O 3 priming, no MeSA and lower LOX emissions were detected under acute exposure. Overall, maximum emission rates and the total amount of emitted LOX products and methanol were quantitatively correlated with total stomatal ozone uptake. These results indicate that different stress volatiles scale differently with ozone dose and highlight the key role of stomatal conductance in controlling ozone uptake, leaf injury and volatile release. © 2017 John Wiley & Sons Ltd.

Ozone-induced foliar damage and release of stress volatiles is highly dependent on stomatal openness and priming by low-level ozone exposure in Phaseolus vulgaris

PubMed Central

Li, Shuai; Harley, Peter C.; Niinemets, Ülo

2018-01-01

Acute ozone exposure triggers major emissions of volatile organic compounds (VOC), but quantitatively, it is unclear how different ozone doses alter the start and the total amount of these emissions, and the induction rate of different stress volatiles. It is also unclear whether priming (i.e., pre-exposure to lower O3 concentrations) can modify the magnitude and kinetics of volatile emissions. We investigated photosynthetic characteristics and VOC emissions in Phaseolus vulgaris following acute ozone exposure (600 nmol mol-1 for 30 min) under illumination and in darkness and after priming with 200 nmol mol-1 O3 for 30 min. Methanol and lipoxygenase (LOX) pathway product emissions were induced rapidly, followed by moderate emissions of methyl salicylate (MeSA). Stomatal conductance prior to acute exposure was lower in darkness and after low O3 priming than in light and without priming. After low O3 priming, no MeSA and lower LOX emissions were detected under acute exposure. Overall, maximum emission rates and the total amount of emitted LOX products and methanol were quantitatively correlated with total stomatal ozone uptake. These results indicate that different stress volatiles scale differently with ozone dose and highlight the key role of stomatal conductance in controlling ozone uptake, leaf injury and volatile release. PMID:28623868

Emission of particulate matter from a desktop three-dimensional (3D) printer

PubMed Central

Yi, Jinghai; LeBouf, Ryan F.; Duling, Matthew G.; Nurkiewicz, Timothy; Chen, Bean T.; Schwegler-Berry, Diane; Virji, M. Abbas; Stefaniak, Aleksandr B.

2016-01-01

ABSTRACT Desktop three-dimensional (3D) printers are becoming commonplace in business offices, public libraries, university labs and classrooms, and even private homes; however, these settings are generally not designed for exposure control. Prior experience with a variety of office equipment devices such as laser printers that emit ultrafine particles (UFP) suggests the need to characterize 3D printer emissions to enable reliable risk assessment. The aim of this study was to examine factors that influence particulate emissions from 3D printers and characterize their physical properties to inform risk assessment. Emissions were evaluated in a 0.5-m3 chamber and in a small room (32.7 m3) using real-time instrumentation to measure particle number, size distribution, mass, and surface area. Factors evaluated included filament composition and color, as well as the manufacturer-provided printer emissions control technologies while printing an object. Filament type significantly influenced emissions, with acrylonitrile butadiene styrene (ABS) emitting larger particles than polylactic acid (PLA), which may have been the result of agglomeration. Geometric mean particle sizes and total particle (TP) number and mass emissions differed significantly among colors of a given filament type. Use of a cover on the printer reduced TP emissions by a factor of 2. Lung deposition calculations indicated a threefold higher PLA particle deposition in alveoli compared to ABS. Desktop 3D printers emit high levels of UFP, which are released into indoor environments where adequate ventilation may not be present to control emissions. Emissions in nonindustrial settings need to be reduced through the use of a hierarchy of controls, beginning with device design, followed by engineering controls (ventilation) and administrative controls such as choice of filament composition and color. PMID:27196745

Effect of 3-nitrooxypropanol on methane and hydrogen emissions, methane isotopic signature, and ruminal fermentation in dairy cows.

PubMed

Lopes, J C; de Matos, L F; Harper, M T; Giallongo, F; Oh, J; Gruen, D; Ono, S; Kindermann, M; Duval, S; Hristov, A N

2016-07-01

The objective of this crossover experiment was to investigate the effect of a methane inhibitor, 3-nitrooxypropanol (3NOP), on enteric methane emission, methane isotopic composition, and rumen fermentation and microbial profile in lactating dairy cows. The experiment involved 6 ruminally cannulated late-lactation Holstein cows assigned to 2 treatments: control and 3NOP (60 mg/kg of feed dry matter). Compared with the control, 3NOP decreased methane emission by 31% and increased hydrogen emission from undetectable to 1.33 g/d. Methane emissions per kilogram of dry matter intake and milk yield were also decreased 34% by 3NOP. Milk production and composition were not affected by 3NOP, except milk fat concentration was increased compared with the control. Concentrations of total VFA and propionate in ruminal fluid were not affected by treatment, but acetate concentration tended to be lower and acetate-to-propionate ratio was lower for 3NOP compared with the control. The 3NOP decreased the molar proportion of acetate and increase those of propionate, butyrate, valerate, and isovalerate. Deuterium-to-hydrogen ratios of methane and the abundance of (13)CH3D were similar between treatments. Compared with the control, minor (4‰) depletion in the (13)C/(12)C ratio was observed for 3NOP. Genus composition of methanogenic archaea (Methanobrevibacter, Methanosphaera, and Methanomicrobium) was not affected by 3NOP, but the proportion of methanogens in the total cell counts tended to be decreased by 3NOP. Prevotella spp., the predominant bacterial genus in ruminal contents in this experiment, was also not affected by 3NOP. Compared with the control, Ruminococcus and Clostridium spp. were decreased and Butyrivibrio spp. was increased by 3NOP. This experiment demonstrated that a substantial inhibition of enteric methane emission by 3NOP in dairy cows was accompanied with increased hydrogen emission and decreased acetate-to-propionate ratio; however, neither an effect on rumen archaeal community composition nor a significant change in the isotope composition of methane was observed. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Life cycle assessment of coal-fired power plants and sensitivity analysis of CO2 emissions from power generation side

NASA Astrophysics Data System (ADS)

Yin, Libao; Liao, Yanfen; Zhou, Lianjie; Wang, Zhao; Ma, Xiaoqian

2017-05-01

The life cycle assessment and environmental impacts of a 1000MW coal-fired power plant were carried out in this paper. The results showed that the operation energy consumption and pollutant emission of the power plant are the highest in all sub-process, which accounts for 93.93% of the total energy consumption and 92.20% of the total emission. Compared to other pollutant emissions from the coal-fired power plant, CO2 reached up to 99.28%. Therefore, the control of CO2 emission from the coal-fired power plants was very important. Based on the BP neural network, the amount of CO2 emission from the generation side of coal-fired power plants was calculated via carbon balance method. The results showed that unit capacity, coal quality and unit operation load had great influence on the CO2 emission from coal-fired power plants in Guangdong Province. The use of high volatile and high heat value of coal also can reduce the CO2 emissions. What’s more, under higher operation load condition, the CO2 emissions of 1 kWh electric energy was less.

Standardized Emission Quantification and Control of Costs for Environmental Measures

NASA Astrophysics Data System (ADS)

Walter, J.; Hustedt, M.; Wesling, V.; Barcikowski, S.

Laser welding and soldering are important industrial joining processes. As is known, LGACs (Laser Generated Air Contaminants) cause costs for environmental measures during production of complex metallic components (steel, aluminium, magnesium, alloys). The hazardous potential of such processes has been assessed by analyzing the specific emissions with respect to relevant threshold limit values (TLVs). Avoiding and controlling emissions caused by laser processing of metals or metal composites is an important task. Using the experimental results, the planning of appropriate exhaust systems for laser processing is facilitated significantly. The costs quantified for environmental measures account for significant percentages of the total manufacturing costs.

Distinguishing the roles of meteorology, emission control measures, regional transport, and co-benefits of reduced aerosol feedbacks in ;APEC Blue;

NASA Astrophysics Data System (ADS)

Gao, Meng; Liu, Zirui; Wang, Yuesi; Lu, Xiao; Ji, Dongsheng; Wang, Lili; Li, Meng; Wang, Zifa; Zhang, Qiang; Carmichael, Gregory R.

2017-10-01

Air quality are strongly influenced by both emissions and meteorological conditions. During the Asia Pacific Economic Cooperation (APEC) week (November 5-11, 2014), the Chinese government implemented unprecedented strict emission control measures in Beijing and surrounding provinces, and then a phenomenon referred to as ;APEC Blue; (rare blue sky) occurred. It is challenging to quantify the effectiveness of the implemented strict control measures solely based on observations. In this study, we use the WRF-Chem model to distinguish the roles of meteorology, emission control measures, regional transport, and co-benefits of reduced aerosol feedbacks during APEC week. In general, meteorological variables, PM2.5 concentrations and PM2.5 chemical compositions are well reproduced in Beijing. Positive weather conditions (lower temperature, lower relative humidity, higher wind speeds and enhanced boundary layer heights) play important roles in ;APEC Blue;. Applying strict emission control measures in Beijing and five surrounding provinces can only explain an average decrease of 17.7 μg/m3 (-21.8%) decreases in PM2.5 concentrations, roughly more than half of which is caused by emission controls that implemented in the five surrounding provinces (12.5 μg/m3). During the APEC week, non-local emissions contributed to 41.3% to PM2.5 concentrations in Beijing, and the effectiveness of implementing emission control measures hinges on dominant pathways and transport speeds. Besides, we also quantified the contribution of reduced aerosol feedbacks due to strict emission control measures in this study. During daytime, co-benefits of reduced aerosol feedbacks account for about 10.9% of the total decreases in PM2.5 concentrations in urban Beijing. The separation of contributions from aerosol absorption and scattering restates the importance of controlling BC to accelerate the effectiveness of aerosol pollution control.

Quantification of hourly variability in NO(x) emissions for baseload coal-fired power plants.

PubMed

Abdel-Aziz, Amr; Frey, H Christopher

2003-11-01

The objectives of this paper are to (1) quantify variability in hourly utility oxides of nitrogen (NO(x)) emission factors, activity factors, and total emissions; (2) investigate the autocorrelation structure and evaluate cyclic effects at short and long scales of the time series of total hourly emissions; (3) compare emissions for the ozone (O3) season versus the entire year to identify seasonal differences, if any; and (4) evaluate interannual variability. Continuous emissions monitoring data were analyzed for 1995 and 1998 for 32 units from nine baseload power plants in the Charlotte, NC, airshed. Unit emissions have a strong 24-hr cycle attributable primarily to the capacity factor. Typical ranges of the coefficient of variation for emissions at a given hour of the day were from 0.2 to 0.45. Little difference was found when comparing weekend emissions with the entire week or when comparing the O3 season with the entire year. There were substantial differences in the mean and standard deviation of emissions when comparing 1995 and 1998 data, indicative of the effect of retrofits of control technology during the intervening time. The wide range of variability and its autocorrelation should be accounted for when developing probabilistic utility emission inventories for analysis of near-term future episodes.

Standardized emissions inventory methodology for open-pit mining areas.

PubMed

Huertas, Jose I; Camacho, Dumar A; Huertas, Maria E

2011-08-01

There is still interest in a unified methodology to quantify the mass of particulate material emitted into the atmosphere by activities inherent to open-pit mining. For the case of total suspended particles (TSP), the current practice is to estimate such emissions by developing inventories based on the emission factors recommended by the USEPA for this purpose. However, there are disputes over the specific emission factors that must be used for each activity and the applicability of such factors to cases quite different to the ones under which they were obtained. There is also a need for particulate matter with an aerodynamic diameter less than 10 μm (PM(10)) emission inventories and for metrics to evaluate the emission control programs implemented by open-pit mines. To address these needs, work was carried out to establish a standardized TSP and PM(10) emission inventory methodology for open-pit mining areas. The proposed methodology was applied to seven of the eight mining companies operating in the northern part of Colombia, home to the one of the world's largest open-pit coal mining operations (∼70 Mt/year). The results obtained show that transport on unpaved roads is the mining activity that generates most of the emissions and that the total emissions may be reduced up to 72% by spraying water on the unpaved roads. Performance metrics were defined for the emission control programs implemented by mining companies. It was found that coal open-pit mines are emitting 0.726 and 0.180 kg of TSP and PM(10), respectively, per ton of coal produced. It was also found that these mines are using on average 1.148 m(2) of land per ton of coal produced per year.

Impact of using fishing boat fuel with high poly aromatic content on the emission of polycyclic aromatic hydrocarbons from the diesel engine

NASA Astrophysics Data System (ADS)

Lin, Yuan-Chung; Lee, Wen-Jhy; Li, Hsing-Wang; Chen, Chung-Ban; Fang, Guor-Cheng; Tsai, Perng-Jy

Because of the fishery subsidy policy, the fishing boat fuel oil (FBFO) exemption from commodity taxes, business taxes and air pollution control fees, resulted in the price of FBFO was ˜50% lower than premium diesel fuel (PDF) in Taiwan. It is estimated that ˜650,000 kL FBFO was illegally used by traveling diesel-vehicles (TDVs) with a heavy-duty diesel engine (HDDE), which accounted for ˜16.3% of the total diesel fuel consumed by TDVs. In this study, sulfur, poly aromatic and total-aromatic contents in both FBFO and PDF were measured and compared. Exhaust emissions of polycyclic aromatic hydrocarbons (PAHs) and their carcinogenic potencies (BaP eq) from a HDDE under transient cycle testing for both FBFO and PDF were compared and discussed. Finally, the impact caused by the illegal use of FBFO on the air quality was examined. Results show that the mean sulfur-, poly aromatic and aromatic-contents in FBFO were 43.0, 3.89 and 1.04 times higher than that of PDF, respectively. Emission factors of total-PAHs and total-BaP eq obtained by utilizing FBFO were 51.5 and 0.235 mg L -1-Fuel, which were 3.41 and 5.82 times in magnitude higher than obtained by PDF, respectively. The estimated annual emissions of total-PAHs and total-BaP eq to the ambient environment due to the illegally used FBFO were 23.6 and 0.126 metric tons, respectively, which resulted in a 17.9% and a 25.0% increment of annual emissions from all mobile sources, respectively. These results indicated that the FBFO used illegally by TDVs had a significant impact on PAH emissions to the ambient environment.

Atmospheric Carbon Tetrachloride: Mysterious Emissions Gap Almost Closed

NASA Astrophysics Data System (ADS)

Liang, Q.; Newman, P. A.; Reimann, S.

2016-12-01

Carbon tetrachloride (CCl4) is a major ozone-depleting substance and its production and consumption is controlled under the Montreal Protocol for emissive uses. The most recent WMO/UNEP Scientific Assessment of Ozone Depletion [WMO, 2014] estimated a 2007-2012 CCl4 bottom-up emission of 1-4 Gg yr-1, based on country-by-country reports to UNEP, vs. a global top-down emissions estimate of 57 Gg yr-1, based on atmospheric measurements. To understand the gap between the top-down and bottom-up emissions estimates, a CCl4 activity was formed under the auspices of the Stratosphere-Troposphere Processes And their Role in Climate (SPARC) project. Several new findings were brought forward by the SPARC CCl4 activity. CCl4 is destroyed in the stratosphere, oceans, and soils. The total lifetime estimate has been increased from 26 to 33 years. The new 33-year total lifetime lowers the top-down emissions estimate to 40 (25-55) Gg yr-1. In addition, a persistent hemispheric difference implies substantial ongoing Northern Hemisphere emissions, yielding an independent emissions estimate of 30 Gg yr-1. The combination of these two yields an emissions estimate of 35 Gg yr-1. Regional estimates have been made for Australia, North America, East Asia, and Western Europe. The sum of these estimates results in emissions of 21 Gg yr-1, albeit this does not include all regions of the world. Four bottom-up CCl4 emissions pathways have been identified, i.e., fugitive, unreported non-feedstock, unreported inadvertent, and legacy emissions. The new industrial bottom-up emissions estimate includes emissions from chloromethanes plants (13 Gg yr-1) and feedstock fugitive emissions (2 Gg yr-1). When combined with legacy emissions and unreported inadvertent emissions ( 10 Gg yr-1), the total global emissions are 20±5 Gg yr-1. While the new bottom-up value is still less than the aggregated top-down values, these estimates reconcile the CCl4 budget discrepancy when considered at the edges of their uncertainties.

An innovative permanent total enclosure for blast cleaning and painting ships in drydock

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garland, C.; Lukey, M.

1997-12-31

This paper describes a new innovative Permanent Total Enclosure, or CAPE system, which encloses and captures emissions from blast cleaning and painting ship hulls in drydock. A description of the modular enclosure towers with unique seals is shown with several figures. The support barge with its environmental control equipment which includes a dust collector, VOC thermal oxidizer, dehumidifier, boiler, heating coils, air flow fans and, system controls is also described. Data measurements from the first two applications rate this system at 100 percent capture efficiency, 99 percent VOC destruction efficiency and 99.9 percent dust collection efficiency. Ships can be blastmore » cleaned and painted using noncompliant paints and meet all state and federal standards for air emissions.« less

Number size distribution of particulate emissions of heavy-duty engines in real world test cycles

NASA Astrophysics Data System (ADS)

Lehmann, Urs; Mohr, Martin; Schweizer, Thomas; Rütter, Josef

Five in-service engines in heavy-duty trucks complying with Euro II emission standards were measured on a dynamic engine test bench at EMPA. The particulate matter (PM) emissions of these engines were investigated by number and mass measurements. The mass of the total PM was evaluated using the standard gravimetric measurement method, the total number concentration and the number size distribution were measured by a Condensation Particle Counter (lower particle size cut-off: 7 nm) and an Electrical Low Pressure Impactor (lower particle size: 32 nm), respectively. The transient test cycles used represent either driving behaviour on the road (real-world test cycles) or a type approval procedure. They are characterised by the cycle power, the average cycle power and by a parameter for the cycle dynamics. In addition, the particle number size distribution was determined at two steady-state operating modes of the engine using a Scanning Mobility Particle Sizer. For quality control, each measurement was repeated at least three times under controlled conditions. It was found that the number size distributions as well as the total number concentration of emitted particles could be measured with a good repeatability. Total number concentration was between 9×10 11 and 1×10 13 particles/s (3×10 13-7×10 14 p/kWh) and mass concentration was between 0.09 and 0.48 g/kWh. For all transient cycles, the number mean diameter of the distributions lay typically at about 120 nm for aerodynamic particle diameter and did not vary significantly. In general, the various particle measurement devices used reveal the same trends in particle emissions. We looked at the correlation between specific gravimetric mass emission (PM) and total particle number concentration. The correlation tends to be influenced more by the different engines than by the test cycles.

Refinery evaluation of optical imaging to locate fugitive emissions.

PubMed

Robinson, Donald R; Luke-Boone, Ronke; Aggarwal, Vineet; Harris, Buzz; Anderson, Eric; Ranum, David; Kulp, Thomas J; Armstrong, Karla; Sommers, Ricky; McRae, Thomas G; Ritter, Karin; Siegell, Jeffrey H; Van Pelt, Doug; Smylie, Mike

2007-07-01

Fugitive emissions account for approximately 50% of total hydrocarbon emissions from process plants. Federal and state regulations aiming at controlling these emissions require refineries and petrochemical plants in the United States to implement a Leak Detection and Repair Program (LDAR). The current regulatory work practice, U.S. Environment Protection Agency Method 21, requires designated components to be monitored individually at regular intervals. The annual costs of these LDAR programs in a typical refinery can exceed US$1,000,000. Previous studies have shown that a majority of controllable fugitive emissions come from a very small fraction of components. The Smart LDAR program aims to find cost-effective methods to monitor and reduce emissions from these large leakers. Optical gas imaging has been identified as one such technology that can help achieve this objective. This paper discusses a refinery evaluation of an instrument based on backscatter absorption gas imaging technology. This portable camera allows an operator to scan components more quickly and image gas leaks in real time. During the evaluation, the instrument was able to identify leaking components that were the source of 97% of the total mass emissions from leaks detected. More than 27,000 components were monitored. This was achieved in far less time than it would have taken using Method 21. In addition, the instrument was able to find leaks from components that are not required to be monitored by the current LDAR regulations. The technology principles and the parameters that affect instrument performance are also discussed in the paper.

The Story of Ever Diminishing Vehicle Tailpipe Emissions as Observed in the Chicago, Illinois Area.

PubMed

Bishop, Gary A; Haugen, Molly J

2018-05-15

The University of Denver has collected on-road fuel specific vehicle emissions measurements in the Chicago area since 1989. This nearly 30 year record illustrates the large reductions in light-duty vehicle tailpipe emissions and the remarkable improvements in emissions control durability to maintain low emissions over increasing periods of time. Since 1989 fuel specific carbon monoxide (CO) emissions have been reduced by an order of magnitude and hydrocarbon (HC) emissions by more than a factor of 20. Nitric oxide (NO) emissions have only been collected since 1997 but have seen reductions of 79%. This has increased the skewness of the emissions distribution where the 2016 fleet's 99th percentile contributes ∼3 times more of the 1990 total for CO and HC emissions. There are signs that these reductions may be leveling out as the emissions durability of Tier 2 vehicles in use today has almost eliminated the emissions reduction benefit of fleet turnover. Since 1997, the average age of the Chicago on-road fleet has increased 2 model years and the percentage of passenger vehicles has dropped from 71 to 52% of the fleet. Emissions are now so well controlled that the influence of driving mode has been completely eliminated as a factor for fuel specific CO and NO emissions.

An estimate of carbon emissions from 2004 wildfires across Alaskan Yukon River Basin

USGS Publications Warehouse

Tan, Zhengxi; Tieszen, Larry L.; Zhu, Zhiliang; Liu, Shuguang; Howard, Stephen M.

2007-01-01

BackgroundWildfires are an increasingly important component of the forces that drive the global carbon (C) cycle and climate change as progressive warming is expected in boreal areas. This study estimated C emissions from the wildfires across the Alaskan Yukon River Basin in 2004. We spatially related the firescars to land cover types and defined the C fractions of aboveground biomass and the ground layer (referring to the top 15 cm organic soil layer only in this paper) consumed in association with land cover types, soil drainage classes, and the C stocks in the ground layer.ResultsThe fires led to a burned area of 26,500 km2 and resulted in the total C emission of 81.1 ± 13.6 Tg (Tg, Teragram; 1 Tg = 1012 g) or 3.1 ± 0.7 kg C m-2 burned. Of the total C emission, about 73% and 27% could be attributed to the consumption of the ground layer and aboveground biomass, respectively.ConclusionThe predominant contribution of the ground layer to the total C emission implies the importance of ground fuel management to the control of wildfires and mitigation of C emissions. The magnitude of the total C emission depends on fire extent, while the C loss in kg C m-2 burned is affected strongly by the ground layer and soil drainage condition. The significant reduction in the ground layer by large fires may result in profound impacts on boreal ecosystem services with an increase in feedbacks between wildfires and climate change.

Intelligent Bioreactor Management Information System (IBM-IS) for Mitigation of Greenhouse Gas Emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul Imhoff; Ramin Yazdani; Don Augenstein

Methane is an important contributor to global warming with a total climate forcing estimated to be close to 20% that of carbon dioxide (CO2) over the past two decades. The largest anthropogenic source of methane in the US is 'conventional' landfills, which account for over 30% of anthropogenic emissions. While controlling greenhouse gas emissions must necessarily focus on large CO2 sources, attention to reducing CH4 emissions from landfills can result in significant reductions in greenhouse gas emissions at low cost. For example, the use of 'controlled' or bioreactor landfilling has been estimated to reduce annual US greenhouse emissions by aboutmore » 15-30 million tons of CO2 carbon (equivalent) at costs between $3-13/ton carbon. In this project we developed or advanced new management approaches, landfill designs, and landfill operating procedures for bioreactor landfills. These advances are needed to address lingering concerns about bioreactor landfills (e.g., efficient collection of increased CH4 generation) in the waste management industry, concerns that hamper bioreactor implementation and the consequent reductions in CH4 emissions. Collectively, the advances described in this report should result in better control of bioreactor landfills and reductions in CH4 emissions. Several advances are important components of an Intelligent Bioreactor Management Information System (IBM-IS).« less

Estimates of ozone response to various combinations of NO(x) and VOC emission reductions in the eastern United States

NASA Technical Reports Server (NTRS)

Roselle, Shawn J.; Schere, Kenneth L.; Chu, Shao-Hang

1994-01-01

There is increasing recognition that controls on NO(x) emissions may be necessary, in addition to existing and future Volatile Organic Compounds (VOC) controls, for the abatement of ozone (O3) over portions of the United States. This study compares various combinations of anthropogenic NO(x) and VOC emission reductions through a series of model simulations. A total of 6 simulations were performed with the Regional Oxidant Model (ROM) for a 9-day period in July 1988. Each simulation reduced anthropogenic NO(x) and VOC emissions across-the-board by different amounts. Maximum O3 concentrations for the period were compared between the simulations. Comparison of the simulations suggests that: (1) NO(x) controls may be more effective than VOC controls in reducing peak O3 over most of the eastern United States; (2) VOC controls are most effective in urban areas having large sources of emissions; (3) NO(x) controls may increase O3 near large point sources; and (4) the benefit gained from increasing the amount of VOC controls may lessen as the amount of NO(x) control is increased. This paper has been reviewed in accordance with the U.S. Environmental Protection Agency's peer and administrative review policies and approved for presentation and publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.

Recent NASA/GSFC cryogenic measurements of the total hemispheric emissivity of black surface preparations

NASA Astrophysics Data System (ADS)

Tuttle, J.; Canavan, E.

2015-12-01

High-emissivity (black) surfaces are commonly used on deep-space radiators and thermal radiation absorbers in test chambers. Since 2011 NASA Goddard Space Flight Center has measured the total hemispheric emissivity of such surfaces from 20 to 300 K using a test apparatus inside a small laboratory cryostat. We report the latest data from these measurements, including Aeroglaze Z307 paint, Black Kapton, and a configuration of painted aluminum honeycomb that was not previously tested. We also present the results of batch-to- batch reproducibility studies in Ball Infrared BlackTM and painted aluminum honeycomb. Finally, we describe a recently-adopted temperature control method which significantly speeds the data acquisition, and we discuss efforts to reduce the noise in future data.

Control strategies for the reduction of airborne particulate nitrate in California's San Joaquin Valley

NASA Astrophysics Data System (ADS)

Kleeman, Michael J.; Ying, Qi; Kaduwela, Ajith

The effect of NO x, volatile organic compound (VOC), and NH 3 emissions control programs on the formation of particulate ammonium nitrate in the San Joaquin Valley (SJV) was examined under the typical winter conditions that existed on 4-6 January, 1996. The UCD/CIT photochemical transport model was used for this study so that the source origin of primary particulate matter and secondary particulate matter could be identified. When averaged across the entire SJV, the model results predict that 13-18% of the reactive nitrogen (NO y=NO x+reaction products of NO x) emitted from local sources within the SJV was converted to nitrate at the ground level. Each gram of NO x emitted locally within the SJV (expressed as NO 2) produced 0.23-0.31 g of particulate ammonium nitrate (NH 4NO 3), which is much smaller than the maximum theoretical yield of 1.7 g of NH 4NO 3 per gram of NO 2. The fraction of reactive nitrogen converted to nitrate varied strongly as a function of location. Urban regions with large amounts of fresh NO emissions converted little reactive nitrogen to nitrate, while remote areas had up to 70% conversion (equivalent to approximately 1.2 g of NH 4NO 3 per gram of NO 2). The use of a single spatially averaged ratio of NH 4NO 3/NO x as a predictor of how changes to NO x emissions would affect particulate nitrate concentrations would not be accurate at all locations in the SJV under the conditions studied. The largest local sources of particulate nitrate in the SJV were predicted to be diesel engines and catalyst equipped gasoline engines under the conditions experienced on 6 January, 1996. Together, these sources accounted for less than half of the ground-level nitrate aerosol in the SJV. The remaining fraction of the aerosol nitrate originated from reactive nitrogen originally released upwind of the SJV. The majority of this upwind reactive nitrogen was already transformed to nitrate by the time it entered the SJV. The effect of local emissions controls on this upwind material was small. A 50% reduction in NO x emissions applied to sources within the SJV reduced the predicted concentration of total nitrate by approximately 25% during the study episode. VOC emissions controls were less effective, while reasonable NH 3 emissions controls had the smallest effect on the amount of ammonium nitrate produced. A 50% reduction in VOC emissions lowered predicted concentrations of total nitrate by 17.5%, while a 50% reduction in NH 3 emissions lowered predicted concentrations of total nitrate by only 10%. This latter result is expected since the formation of ammonium nitrate aerosol is limited by the availability of gas-phase nitric acid, with large amounts of excess NH 3 available. NO x emissions controls appear to be the most efficient method to reduce the concentration of locally generated particulate nitrate in the SJV under the conditions experienced on 4-6 January, 1996.

[Temporal and spatial distribution of anthropogenic ammonia emissions in China: 1994-2006].

PubMed

Dong, Wen-xuan; Xing, Jia; Wang, Shu-xiao

2010-07-01

Ammonia has both direct and indirect impacts on important environmental issues including acid deposition, regional fine particles and eutrophication. Estimation of anthropogenic ammonia emissions will provide valuable information for the pollution control of acid deposition and regional fine particle. Based on the provincial activity data on N-fertilizer application, livestock farming, N-fertilizer production and populations, this paper uses emission factor method to estimate China's atmospheric ammonia emissions, analyzes its historical trends and presents its geographical distributions from year 1994 to 2006. The national total atmospheric ammonia emissions are estimated to be 11.06 million tons (Mt) in 1994, which increase quickly to 16.07 Mt in 2006. Emissions from livestock farming, N-fertilizer application, N-fertilizer production and human excreta have increased from 4.47 Mt, 5.94 Mt, 0.09 Mt, and 0.59 Mt in 1994 to 6.61 Mt, 8.68 Mt, 0.14 Mt, 0.65 Mt respectively in 2006. Livestock farming and N-fertilizer application are the most important ammonia emission sources, which contributed 40.79 and 55.53 percent of total emissions respectively in 2006. In 2006, the average ammonia emission intensity is 1.67 t x km(-2) but there are large variations among atmospheric ammonia emissions from each province. Emissions from provinces including Henan, Shandong, Hebei, Sichuan and Jiangsu accounted for 40.82 percent of national emissions.

40 CFR 60.7 - Notification and record keeping.

Code of Federal Regulations, 2010 CFR

2010-07-01

... control systems, productive capacity of the facility before and after the change, and the expected... submitted for each pollutant monitored at each affected facility. (1) If the total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting...

40 CFR 60.7 - Notification and record keeping.

Code of Federal Regulations, 2013 CFR

2013-07-01

... control systems, productive capacity of the facility before and after the change, and the expected... submitted for each pollutant monitored at each affected facility. (1) If the total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting...

40 CFR 60.7 - Notification and record keeping.

Code of Federal Regulations, 2011 CFR

2011-07-01

... control systems, productive capacity of the facility before and after the change, and the expected... submitted for each pollutant monitored at each affected facility. (1) If the total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting...

40 CFR 60.7 - Notification and record keeping.

Code of Federal Regulations, 2014 CFR

2014-07-01

... control systems, productive capacity of the facility before and after the change, and the expected... submitted for each pollutant monitored at each affected facility. (1) If the total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting...

40 CFR 60.7 - Notification and record keeping.

Code of Federal Regulations, 2012 CFR

2012-07-01

... control systems, productive capacity of the facility before and after the change, and the expected... submitted for each pollutant monitored at each affected facility. (1) If the total duration of excess emissions for the reporting period is less than 1 percent of the total operating time for the reporting...

40 CFR Table 5 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Transfer Racks

Code of Federal Regulations, 2012 CFR

2012-07-01

... each . . . You must . . . 1. Group 1 transfer rack a. Reduce emissions of total organic HAP by ≥98... through a closed-vent system to any combination of control devices (except a flare); or b. Reduce....982(d) and the requirements referenced therein; or d. Use a vapor balancing system designed and...

40 CFR Table 5 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Transfer Racks

Code of Federal Regulations, 2014 CFR

2014-07-01

... each . . . You must . . . 1. Group 1 transfer rack a. Reduce emissions of total organic HAP by ≥98... through a closed-vent system to any combination of control devices (except a flare); or b. Reduce....982(d) and the requirements referenced therein; or d. Use a vapor balancing system designed and...

40 CFR Table 5 to Subpart Ffff of... - Emission Limits and Work Practice Standards for Transfer Racks

Code of Federal Regulations, 2010 CFR

2010-07-01

... each . . . You must . . . 1. Group 1 transfer rack a. Reduce emissions of total organic HAP by ≥98... through a closed-vent system to any combination of control devices (except a flare); or b. Reduce....982(d) and the requirements referenced therein; or d. Use a vapor balancing system designed and...

40 CFR 63.494 - Back-end process provisions-residual organic HAP and emission limitations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... be measured after the stripping operation (or the reactor(s), if the plant has no stripper(s)), as... operation (or the reactor(s), if the plant has no stripper(s)). The limitation shall be calculated and... = Controlled emissions in 2009, Mg/yr P2009 = Total elastomer product leaving the stripper in 2009, Mg/yr...

40 CFR 63.494 - Back-end process provisions-residual organic HAP and emission limitations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... be measured after the stripping operation (or the reactor(s), if the plant has no stripper(s)), as... operation (or the reactor(s), if the plant has no stripper(s)). The limitation shall be calculated and... = Controlled emissions in 2009, Mg/yr P2009 = Total elastomer product leaving the stripper in 2009, Mg/yr...

Emission of floral volatiles from Mahonia japonica (Berberidaceae).

PubMed

Picone, Joanne M; MacTavish, Hazel S; Clery, Robin A

2002-07-01

Flowering Mahonia japonica plants were subjected to controlled environments and the floral volatiles emitted from whole racemes (laterals) were trapped by Porapak Q adsorbent and analysed by GC-FID. An experiment with photoperiods of 6 and 9 h at constant temperature (10+/-1 degrees C) demonstrated that photoperiod was the stimulus for enhanced emission of most volatiles. Small quantitative differences in emitted fragrance composition were observed between light and dark periods and between plants acclimatised to different photoperiods. Maximum rates of emission occurred in the middle of the light period; aromatic compounds (benzaldehyde, benzyl alcohol and indole) displayed a more rapid increase and subsequent decline compared with monoterpenes (cis- and trans-ocimene and linalool). When the photoperiod was extended from 6 to 9 h, maximum rates of emission continued throughout the additional 3 h. Total emission (microg/h) of volatiles was 2-fold greater in the day-time (DT) (39.7 microg/h) compared with the night-time (NT) (19.8 microgg/h) under a 6 h photoperiod and was not significantly different from total emission under a 9 h photoperiod.

Atmospheric pollution reduction effect and regional predicament: An empirical analysis based on the Chinese provincial NOx emissions.

PubMed

Ding, Lei; Liu, Chao; Chen, Kunlun; Huang, Yalin; Diao, Beidi

2017-07-01

Atmospheric pollution emissions have become a matter of public concern in recent years. However, most of the existing researches on NOx pollution are from the natural science and technology perspective, few studies have been conducted from an economic point, and regional differences have not been given adequate attention. This paper adopts provincial panel data from 2006 to 2013 and the LMDI model to analyze the key driving factors and regional dilemmas of NOx emissions. The results show that significant regional disparities still exit on NO x emissions and its reduction effect 27 provinces didn't accomplish their corresponding reduction targets. Economic development factor is the dominating driving factor of NO x emissions during the study period, while energy efficiency and technology improvement factors offset total NO x emissions in the majority of provinces. In addition, the industrial structure factor plays a more significant role in reducing the NO x emissions after 2011. Therefore, the government should consider all these factors as well as regional heterogeneity in developing appropriate pollution mitigating policies. It's necessary to change NOx emissions control attitude from original key areas control to divided-zone control, not only attaches great importance to the reduction of the original key areas, but also emphasizes the new potential hotspots with high NO x emissions. Copyright © 2017 Elsevier Ltd. All rights reserved.

40 CFR 1065.1001 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... engine parameters. Emission-control system means any device, system, or element of design that controls.... Nonmethane hydrocarbon equivalent (NMHCE) means the sum of the carbon mass contributions of non-oxygenated... of 1.85:1. Total hydrocarbon equivalent (THCE) means the sum of the carbon mass contributions of non...

40 CFR 1065.1001 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... engine parameters. Emission-control system means any device, system, or element of design that controls.... Nonmethane hydrocarbon equivalent (NMHCE) means the sum of the carbon mass contributions of non-oxygenated... of 1.85:1. Total hydrocarbon equivalent (THCE) means the sum of the carbon mass contributions of non...

[Spatial heterogeneity and classified control of agricultural non-point source pollution in Huaihe River Basin].

PubMed

Zhou, Liang; Xu, Jian-Gang; Sun, Dong-Qi; Ni, Tian-Hua

2013-02-01

Agricultural non-point source pollution is of importance in river deterioration. Thus identifying and concentrated controlling the key source-areas are the most effective approaches for non-point source pollution control. This study adopts inventory method to analysis four kinds of pollution sources and their emissions intensity of the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in 173 counties (cities, districts) in Huaihe River Basin. The four pollution sources include livestock breeding, rural life, farmland cultivation, aquacultures. The paper mainly addresses identification of non-point polluted sensitivity areas, key pollution sources and its spatial distribution characteristics through cluster, sensitivity evaluation and spatial analysis. A geographic information system (GIS) and SPSS were used to carry out this study. The results show that: the COD, TN and TP emissions of agricultural non-point sources were 206.74 x 10(4) t, 66.49 x 10(4) t, 8.74 x 10(4) t separately in Huaihe River Basin in 2009; the emission intensity were 7.69, 2.47, 0.32 t.hm-2; the proportions of COD, TN, TP emissions were 73%, 24%, 3%. The paper achieves that: the major pollution source of COD, TN and TP was livestock breeding and rural life; the sensitivity areas and priority pollution control areas among the river basin of non-point source pollution are some sub-basins of the upper branches in Huaihe River, such as Shahe River, Yinghe River, Beiru River, Jialu River and Qingyi River; livestock breeding is the key pollution source in the priority pollution control areas. Finally, the paper concludes that pollution type of rural life has the highest pollution contribution rate, while comprehensive pollution is one type which is hard to control.

Estimation of automobile emissions and control strategies in India.

PubMed

Nesamani, K S

2010-03-15

Rapid, but unplanned urban development and the consequent urban sprawl coupled with economic growth have aggravated auto dependency in India over the last two decades. This has resulted in congestion and pollution in cities. The central and state governments have taken many ameliorative measures to reduce vehicular emissions. However, evolution of scientific methods for emission inventory is crucial. Therefore, an attempt has been made to estimate the emissions (running and start) from on-road vehicles in Chennai using IVE model in this paper. GPS was used to collect driving patterns. The estimated emissions from motor vehicles in Chennai in 2005 were 431, 119, 46, 7, 4575, 29, and 0.41 tons/days respectively for CO, VOC, NO(x), PM, CO(2,) CH(4) and N(2)O. It is observed from the results that air quality in Chennai has degraded. The estimation revealed that two and three-wheelers emitted about 64% of the total CO emissions and heavy-duty vehicles accounted for more than 60% and 36% of the NO(x) and PM emissions respectively. About 19% of total emissions were that of start emissions. It is also estimated that on-road transport contributes about 6637 tons/day CO(2) equivalent in Chennai. This paper has further examined various mitigation options to reduce vehicular emissions. The study has concluded that advanced vehicular technology and augmentation of public transit would have significant impact on reducing vehicular emissions.

40 CFR Table 4 to Subpart Kkkk of... - Operating Limits If Using the Emission Rate With Add-on Controls Option or the Control Efficiency...

Code of Federal Regulations, 2013 CFR

2013-07-01

... items in 2.a, 2.b, and 2.c of this table. 4. Carbon adsorber a. The total regeneration desorbing gas (e.g., steam or nitrogen) mass flow for each carbon bed regeneration cycle must not fall below the total regeneration desorbing gas mass flow limit established according to § 63.3546(d) or § 63.3556(d...

40 CFR Table 4 to Subpart Kkkk of... - Operating Limits If Using the Emission Rate With Add-on Controls Option or the Control Efficiency...

Code of Federal Regulations, 2011 CFR

2011-07-01

..., 2.b, and 2.c of this table. 4. Carbon adsorber a. The total regeneration desorbing gas (e.g., steam or nitrogen) mass flow for each carbon bed regeneration cycle must not fall below the total regeneration desorbing gas mass flow limit established according to § 63.3546(d) or § 63.3556(d). i. Measuring...

40 CFR Table 4 to Subpart Kkkk of... - Operating Limits If Using the Emission Rate With Add-on Controls Option or the Control Efficiency...

Code of Federal Regulations, 2014 CFR

2014-07-01

... items in 2.a, 2.b, and 2.c of this table. 4. Carbon adsorber a. The total regeneration desorbing gas (e.g., steam or nitrogen) mass flow for each carbon bed regeneration cycle must not fall below the total regeneration desorbing gas mass flow limit established according to § 63.3546(d) or § 63.3556(d...

40 CFR Table 4 to Subpart Kkkk of... - Operating Limits If Using the Emission Rate With Add-on Controls Option or the Control Efficiency...

Code of Federal Regulations, 2012 CFR

2012-07-01

... items in 2.a, 2.b, and 2.c of this table. 4. Carbon adsorber a. The total regeneration desorbing gas (e.g., steam or nitrogen) mass flow for each carbon bed regeneration cycle must not fall below the total regeneration desorbing gas mass flow limit established according to § 63.3546(d) or § 63.3556(d...

[Analysis on relationship between regional economic development and sewage disposal].

PubMed

Wang, La-Chun; Huo, Yu; Zhu, Ji-Ye; Li, Sheng-Feng; Gao, Chao

2008-03-01

Based on the relationship between district GDP and sewage disposal, the water environment protection effect in 3 cities, Suzhou, Nanjing and Xuzhou, with different economic development degrees in Jiangsu Province was dynamically analyzed. The economy in Suzhou was well developed, where the foreign capital proportion was in a high level. Its GDP per capita was 53,800 yuan in 2005 and the sewage disposal grew linearly when its GDP increased in the study time period. Nanjing was less developed than Suzhou, and the state-owned enterprises in large and medium sizes were in a high percentage. Its GDP per capita was 37,100 yuan in 2005, while the sewage disposal reduced linearly when its GDP increased in the study time period. The economy in Xuzhou is under-developed, where coal-based heavy industry was the most important one. The GDP per capita in this city was 13,200 yuan in 2005 and the sewage disposal fluctuated when its GDP increased in the study time period. According to the relationship between economic development and sewage disposal in different cities, we suggested that the water environment protection in Suzhou should focus on the control of both water pollutant total emission and emission concentration, the major work in Nanjing should focus on adjusting the industrial structure and meanwhile controlling the total emission of water pollutants, while in Xuzhou the water pollutant emission concentration should be firstly controlled.

Influence of 13 different biochars on N2O production and its sources during rewetting-drying cycles

NASA Astrophysics Data System (ADS)

Wrage-Mönnig, Nicole; Fiedler, Sebastian; Fuertes-Mendizábal, Teresa; Estavillo, José-Maria; Ippolito, Jim A.; Borchard, Nils; Cayuela, Maria Luz; Spokas, Kurt; Novak, Jeff; Kammann, Claudia

2017-04-01

Biochars have been found to have variable impacts on nitrous oxide (N2O) emissions. The variability has been attributed to differences in soil - biochar properties and microbial communities. While some information exists on biochar and soil properties, the effect of biochars on microbial sources of N2O is still a matter of speculation. In this study, we tested these effects for12 biochars prepared from cypress, loblolly pine and grape wood produced at four different controlled temperatures (350, 500, 700 and 900˚ C), respectively, plus a grapevine Kontiki biochar (600-700˚ C). The biochars were added (2%) to a loamy sand brought to pH 7.1 with CaO. The treatments plus one control were pre-incubated at 40% water holding capacity (WHC) for four days. Then, they were brought to 80% WHC and 15N-nitrate was added (50 mg NO3-N kg-1 soil, 10% enriched in 15N). All treatments were set up with four replicates. In total, three cycles of (re)wetting - drying (80 to 40% WHC, total duration 20 days) were monitored. Samples for analyses of N2O concentrations and stable isotope signatures were taken daily (except for weekends) after closing the incubation vessels for 90 minutes. N2O emissions increased with each addition of water and decreased during drying to background values. Each rewetting led to larger emissions than measured in the previous cycle for all treatments including controls. All biochars decreased total N2O emissions compared to the control treatments. The higher the production temperature of the biochar, the larger usually the emission reduction. Largest effects were found for the grape wood and the Kontiki biochars. Interestingly, the addition of biochars also changed the isotopic signatures of the emitted N2O. Whereas emissions in the controls were enriched to about 5 atom% 15N excess at peak emissions, the enrichment was usually less after addition of biochars (1-5 atom% excess). Again, this effect tended to be larger at higher production temperatures of the biochars and was greatest for the grape wood and Kontiki biochars. The results indicate that NO3- was an important source for N2O emissions under the conditions of the study, probably by denitrification. The addition of biochars changed not only the amount of emissions, but also the N source of emissions. In this study, N2O production from labelled NO3- was a smaller source of emissions after addition of biochars (especially produced at high temperatures) than in control treatments. This indicates that the 15N-NO3- source was diluted by (accelerated) mineralization-nitrification or that microbial sources using other substrates but added NO3- contributed more to N2O production. Whether potential capture of NO3- by biochars could contribute to this, needs to be further investigated. Acknowledgements: This contribution was made possible by the 'DesignChar4Food' project (D4F) funded by the BLE and FACCE-JPI (German partners), by FACCE-CSA n° 276610/MIT04-DESIGN-UPVASC and IT-932-16 (Spanish partners), and the USDA-National Institute of Food and Agriculture (Project # 2014-35615-21971; US colleagues) plus USDA-ARS CHARnet and GRACENetprograms. CK gratefully acknowledges funding by DFG grant KA3442/1-1 and "OptiChar4EcoVin" (Hessian Ministry for Higher Education, Research and the Arts).

Greenhouse Gas and Noxious Emissions from Dual Fuel Diesel and Natural Gas Heavy Goods Vehicles.

PubMed

Stettler, Marc E J; Midgley, William J B; Swanson, Jacob J; Cebon, David; Boies, Adam M

2016-02-16

Dual fuel diesel and natural gas heavy goods vehicles (HGVs) operate on a combination of the two fuels simultaneously. By substituting diesel for natural gas, vehicle operators can benefit from reduced fuel costs and as natural gas has a lower CO2 intensity compared to diesel, dual fuel HGVs have the potential to reduce greenhouse gas (GHG) emissions from the freight sector. In this study, energy consumption, greenhouse gas and noxious emissions for five after-market dual fuel configurations of two vehicle platforms are compared relative to their diesel-only baseline values over transient and steady state testing. Over a transient cycle, CO2 emissions are reduced by up to 9%; however, methane (CH4) emissions due to incomplete combustion lead to CO2e emissions that are 50-127% higher than the equivalent diesel vehicle. Oxidation catalysts evaluated on the vehicles at steady state reduced CH4 emissions by at most 15% at exhaust gas temperatures representative of transient conditions. This study highlights that control of CH4 emissions and improved control of in-cylinder CH4 combustion are required to reduce total GHG emissions of dual fuel HGVs relative to diesel vehicles.

Vehicular volatile organic compounds losses due to refueling and diurnal process in China: 2010-2050.

PubMed

Yang, Xiaofan; Liu, Huan; Cui, Hongyang; Man, Hanyang; Fu, Mingliang; Hao, Jiming; He, Kebin

2015-07-01

Volatile organic compounds (VOCs) are crucial to control air pollution in major Chinese cities since VOCs are the dominant factor influencing ambient ozone level, and also an important precursor of secondary organic aerosols. Vehicular evaporative emissions have become a major and growing source of VOC emissions in China. This study consists of lab tests, technology evaluation, emissions modeling, policy projections and cost-benefit analysis to draw a roadmap for China for controlling vehicular evaporative emissions. The analysis suggests that evaporative VOC emissions from China's light-duty gasoline vehicles were approximately 185,000 ton in 2010 and would peak at 1,200,000 ton in 2040 without control. The current control strategy implemented in China, as shown in business as usual (BAU) scenario, will barely reduce the long-term growth in emissions. Even if Stage II gasoline station vapor control policies were extended national wide (BAU+extended Stage II), there would still be over 400,000 ton fuel loss in 2050. In contrast, the implementation of on-board refueling vapor recovery (ORVR) on new cars could reduce 97.5% of evaporative VOCs by 2050 (BAU+ORVR/BAU+delayed ORVR). According to the results, a combined Stage II and ORVR program is a comprehensive solution that provides both short-term and long-term benefits. The net cost to achieve the optimal total evaporative VOC control is approximately 62 billion CNY in 2025 and 149 billion CNY in 2050. Copyright © 2015. Published by Elsevier B.V.

The effects of emission control strategies on light-absorbing carbon emissions from a modern heavy-duty diesel engine.

PubMed

Robinson, Michael A; Olson, Michael R; Liu, Z Gerald; Schauer, James J

2015-06-01

Control of atmospheric black carbon (BC) and brown carbon (BrC) has been proposed as an important pathway to climate change mitigation, but sources of BC and BrC are still not well understood. In order to better identify the role of modern heavy-duty diesel engines on the production of BC and BrC, emissions from a heavy-duty diesel engine operating with different emission control strategies were examined using a source dilution sampling system. The effect of a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) on light-absorbing carbon (LAC) was evaluated at three steady-state engine operation modes: idle, 50% speed and load, and 100% speed and load. LAC was measured with four different engine configurations: engine out, DOC out, DPF out, and engine out with an altered combustion calibration. BC and BrC emission rates were measured with the Aethalometer (AE-31). EC and BC emission rates normalized to the mass of CO₂emitted increased with increasing engine speed and load. Emission rates normalized to brake-specific work did not exhibit similar trends with speed and load, but rather the highest emission rate was measured at idle. EC and OC emissions were reduced by 99% when the DOC and DPF architecture was applied. The application of a DPF was equally effective at removing 99% of the BC fraction of PM, proving to be an important control strategy for both LAC and PM. BC emissions were unexpectedly increased across the DOC, seemingly due to a change aerosol optical properties. Removal of exhaust gas recirculation (EGR) flow due to simulated EGR cooler failure caused a large increase in OC and BrC emission rates at idle, but had limited influence during high load operation. LAC emissions proved to be sensitive to the same control strategies effective at controlling the total mass of diesel PM. In the context of black carbon emissions, very small emission rates of brown carbon were measured over a range of control technologies and engine operating conditions. During specific idle engine operation without EGR and adjusted fueling conditions, brown carbon can be formed in significant amounts, requiring careful management tactics. Control technologies for particulate matter are very effective for light-absorbing carbon, reducing black carbon emissions to near zero for modern engines equipped with a DPF. Efforts to control atmospheric brown carbon need to focus on other sources other than modern diesel engines, such as biomass burning.

Direct measurements of methane emissions from abandoned oil and gas wells in Pennsylvania.

PubMed

Kang, Mary; Kanno, Cynthia M; Reid, Matthew C; Zhang, Xin; Mauzerall, Denise L; Celia, Michael A; Chen, Yuheng; Onstott, Tullis C

2014-12-23

Abandoned oil and gas wells provide a potential pathway for subsurface migration and emissions of methane and other fluids to the atmosphere. Little is known about methane fluxes from the millions of abandoned wells that exist in the United States. Here, we report direct measurements of methane fluxes from abandoned oil and gas wells in Pennsylvania, using static flux chambers. A total of 42 and 52 direct measurements were made at wells and at locations near the wells ("controls") in forested, wetland, grassland, and river areas in July, August, October 2013 and January 2014, respectively. The mean methane flow rates at these well locations were 0.27 kg/d/well, and the mean methane flow rate at the control locations was 4.5 × 10(-6) kg/d/location. Three out of the 19 measured wells were high emitters that had methane flow rates that were three orders of magnitude larger than the median flow rate of 1.3 × 10(-3) kg/d/well. Assuming the mean flow rate found here is representative of all abandoned wells in Pennsylvania, we scaled the methane emissions to be 4-7% of estimated total anthropogenic methane emissions in Pennsylvania. The presence of ethane, propane, and n-butane, along with the methane isotopic composition, indicate that the emitted methane is predominantly of thermogenic origin. These measurements show that methane emissions from abandoned oil and gas wells can be significant. The research required to quantify these emissions nationally should be undertaken so they can be accurately described and included in greenhouse gas emissions inventories.

Soil Greenhouse Gas Fluxes, Environmental Controls, and the Partitioning of N2O Sources in UK Natural and Seminatural Land Use Types

NASA Astrophysics Data System (ADS)

Sgouridis, Fotis; Ullah, Sami

2017-10-01

Natural and seminatural terrestrial ecosystems (unmanaged peatlands and forests and extensive and intensive grasslands) have been under-represented in the UK greenhouse gas (GHG) inventory. Mechanistic studies of GHG fluxes and their controls can improve the prediction of the currently uncertain GHG annual emission estimates. The source apportionment of N2O emissions can further inform management plans for GHG mitigation. We have measured in situ GHG fluxes monthly in two replicated UK catchments and evaluated their environmental controlling factors. An adapted 15N-gas flux method with low addition of 15N tracer (0.03-0.5 kg 15N ha-1) was used to quantify the relative contribution of denitrification to net N2O production. Total N2O fluxes were 40 times higher in the intensive grasslands than in the peatlands (range: -1.32 to 312.3 μg N m-2 h-1). The contribution of denitrification to net N2O emission varied across the land use types and ranged from 9 to 60%. Soil moisture was the key parameter regulating the partitioning of N2O sources (r2 = 0.46). Total N2O fluxes were explained by a simple model (r2 = 0.83) including parameters such as total dissolved nitrogen, organic carbon, and water content. A parsimonious model with the soil moisture content as a single scalar parameter explained 84% of methane flux variability across land uses. The assumption that 1% of the atmospherically deposited N on natural ecosystems is emitted as N2O could be overestimated or underestimated (0.3-1.6%). The use of land use-specific N2O emission factors and further information on N2O source partitioning should help constrain this uncertainty.

40 CFR 1065.1001 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

...-control system means any device, system, or element of design that controls or reduces the emissions of... equivalent (NMHCE) means the sum of the carbon mass contributions of non-oxygenated nonmethane hydrocarbons... of 1.85:1. Total hydrocarbon equivalent (THCE) means the sum of the carbon mass contributions of non...

[Study on control and management for industrial volatile organic compounds (VOCs) in China].

PubMed

Wang, Hai-Lin; Zhang, Guo-Ning; Nei, Lei; Wang, Yu-Fei; Hao, Zheng-Ping

2011-12-01

Volatile organic compounds (VOCs) emitted from industrial sources account for a large percent of total anthropogenic VOCs. In this paper, VOCs emission characterization, control technologies and management were discussed. VOCs from industrial emissions were characterized by high intensity, wide range and uneven distribution, which focused on Bejing-Tianjin Joint Belt, Shangdong Peninsula, Yangtze River Delta and the Pearl River Delta. The current technologies for VOCs treatment include adsorption, catalytic combustion, bio-degradation and others, which were applied in petrochemical, oil vapor recovery, shipbuilding, printing, pharmaceutical, feather manufacturing and so on. The scarcity of related regulations/standards plus ineffective supervision make the VOCs management difficult. Therefore, it is suggested that VOCs treatment be firstly performed from key areas and industries, and then carried out step by step. By establishing of actual reducing amount control system and more detailed VOCs emission standards and regulations, applying practical technologies together with demonstration projects, and setting up VOCs emission registration and classification-related-charge system, VOCs could be reduced effectively.

40 CFR 91.803 - Manufacturer in-use testing program.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES In-Use Testing and Recall... failing engine, two more engines shall be tested until the total number of engines equals ten (10). (2... the total number of engines equals ten (10). (3) If an engine family was certified using carry over...

49 CFR 525.7 - Basis for petition.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to be manufactured in that affected model year; (1) Maximum overall body width, overall length, and... applicable; (6) Drive train configuration and total drive ratio; (7) Emission control system; (8) Dynamometer...

49 CFR 525.7 - Basis for petition.

Code of Federal Regulations, 2011 CFR

2011-10-01

... to be manufactured in that affected model year; (1) Maximum overall body width, overall length, and... applicable; (6) Drive train configuration and total drive ratio; (7) Emission control system; (8) Dynamometer...

49 CFR 525.7 - Basis for petition.

Code of Federal Regulations, 2013 CFR

2013-10-01

... to be manufactured in that affected model year; (1) Maximum overall body width, overall length, and... applicable; (6) Drive train configuration and total drive ratio; (7) Emission control system; (8) Dynamometer...

High-spatiotemporal-resolution ship emission inventory of China based on AIS data in 2014.

PubMed

Chen, Dongsheng; Wang, Xiaotong; Li, Yue; Lang, Jianlei; Zhou, Ying; Guo, Xiurui; Zhao, Yuehua

2017-12-31

Ship exhaust emissions have been considered a significant source of air pollution, with adverse impacts on the global climate and human health. China, as one of the largest shipping countries, has long been in great need of in-depth analysis of ship emissions. This study for the first time developed a comprehensive national-scale ship emission inventory with 0.005°×0.005° resolution in China for 2014, using the bottom-up method based on Automatic Identification System (AIS) data of the full year of 2014. The emission estimation involved 166,546 unique vessels observed from over 15billion AIS reports, covering OGVs (ocean-going vessels), CVs (coastal vessels) and RVs (river vessels). Results show that the total estimated ship emissions for China in 2014 were 1.1937×10 6 t (SO 2 ), 2.2084×10 6 t (NO X ), 1.807×10 5 t (PM 10 ), 1.665×10 5 t (PM 2.5 ), 1.116×10 5 t (HC), 2.419×10 5 t (CO), and 7.843×10 7 t (CO 2 , excluding RVs), respectively. OGVs were the main emission contributors, with proportions of 47%-74% of the emission totals for different species. Vessel type with the most emissions was container (~43.6%), followed by bulk carrier (~17.5%), oil tanker (~5.7%) and fishing ship (~4.9%). Monthly variations showed that emissions from transport vessels had a low point in February, while fishing ship presented two emission peaks in May and September. In terms of port clusters, ship emissions in BSA (Bohai Sea Area), YRD (Yangtze River Delta) and PRD (Pearl River Delta) accounted for ~13%, ~28% and ~17%, respectively, of the total emissions in China. On the contrast, the average emission intensities in PRD were the highest, followed by the YRD and BSA regions. The establishment of this high-spatiotemporal-resolution ship emission inventory fills the gap of national-scale ship emission inventory of China, and the corresponding ship emission characteristics are expected to provide certain reference significance for the management and control of the ship emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

40 CFR 1054.345 - What production-line testing records must I send to EPA?

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND... 1054. We have not changed production processes or quality-control procedures for test engines in a way...) Describe any facility used to test production-line engines and state its location. (2) State the total U.S...

40 CFR 1054.345 - What production-line testing records must I send to EPA?

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND... 1054. We have not changed production processes or quality-control procedures for test engines in a way...) Describe any facility used to test production-line engines and state its location. (2) State the total U.S...

40 CFR 1054.345 - What production-line testing records must I send to EPA?

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND... 1054. We have not changed production processes or quality-control procedures for test engines in a way...) Describe any facility used to test production-line engines and state its location. (2) State the total U.S...

40 CFR 1054.345 - What production-line testing records must I send to EPA?

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND... 1054. We have not changed production processes or quality-control procedures for test engines in a way...) Describe any facility used to test production-line engines and state its location. (2) State the total U.S...

40 CFR 1054.345 - What production-line testing records must I send to EPA?

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND... 1054. We have not changed production processes or quality-control procedures for test engines in a way...) Describe any facility used to test production-line engines and state its location. (2) State the total U.S...

Greenhouse gas emissions from green waste composting windrow.

PubMed

Zhu-Barker, Xia; Bailey, Shannon K; Paw U, Kyaw Tha; Burger, Martin; Horwath, William R

2017-01-01

The process of composting is a source of greenhouse gases (GHG) that contribute to climate change. We monitored three field-scale green waste compost windrows over a one-year period to measure the seasonal variance of the GHG fluxes. The compost pile that experienced the wettest and coolest weather had the highest average CH 4 emission of 254±76gCday -1 dry weight (DW) Mg -1 and lowest average N 2 O emission of 152±21mgNday -1 DW Mg -1 compared to the other seasonal piles. The highest N 2 O emissions (342±41mgNday -1 DW Mg -1 ) came from the pile that underwent the driest and hottest weather. The compost windrow oxygen (O 2 ) concentration and moisture content were the most consistent factors predicting N 2 O and CH 4 emissions from all seasonal compost piles. Compared to N 2 O, CH 4 was a higher contributor to the overall global warming potential (GWP) expressed as CO 2 equivalents (CO 2 eq.). Therefore, CH 4 mitigation practices, such as increasing O 2 concentration in the compost windrows through moisture control, feedstock changes to increase porosity, and windrow turning, may reduce the overall GWP of composting. Based on the results of the present study, statewide total GHG emissions of green waste composting were estimated at 789,000Mg of CO 2 eq., representing 2.1% of total annual GHG emissions of the California agricultural sector and 0.18% of the total state emissions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Greenhouse gas emissions during co-composting of calf mortalities with manure.

PubMed

Xu, Shanwei; Hao, Xiying; Stanford, Kim; McAllister, Tim A; Larney, Francis J; Wang, Jingguo

2007-01-01

Composting may be a viable on-farm option for disposal of cattle carcasses. This study investigated greenhouse gas emissions during co-composting of calf mortalities with manure. Windrows were constructed that contained manure + straw (control compost [CK]) or manure + straw + calf mortalities (CM) using two technologies: a tractor-mounted front-end loader or a shredder bucket. Composting lasted 289 d. The windrows were turned twice (on Days 72 and 190), using the same technology used in their creation. Turning technology had no effect on greenhouse gas emissions or the properties of the final compost. The CO2 (75.2 g d(-1) m(-2)), CH4 (2.503 g d(-1) m(-2)), and N2O (0.370 g d(-1) m(-2)) emissions were higher (p < 0.05) in CM than in CK (25.7, 0.094, and 0.076 g d(-1) m(-2) for CO2, CH4, and N2O, respectively), which reflected differences in materials used to construct the compost windrows and therefore their total C and total N contents. The final CM compost had higher (p < 0.05) total N, total C, and mineral N content (NO3*+ NO2* + NH4+) than did CK compost and therefore has greater agronomic value as a fertilizer.

Toyota's inspection system for vehicular emissions at assembly lines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tanaka, T.; Nakano, H.; Usami, I.

1976-01-01

In order that all Toyota production vehicles may satisfy the emission requirements and be free from possible defects such as catalytic converter damage, a system called ECAS, which allows us to assure satisfactory basic emission performance levels has been developed and put into actual use at assembly lines. This system consists of the following four tests: Idle Test, Functional Test, Short Cycle Test and Steady State Inspection Test. By using this system, all operations from vehicle setup, on a chassis dynamometer to statistical analysis of the data, measurement, judgement of the obtained data, type-out of the results, indication for actionmore » to be taken, data filing and statistical treatment of the data, are processed automatically and controlled by the computer. In the Short Cycle Test the up-stream emissions of the vehicle, tracing Toyota's unique short cyclic mode on a chassis dynamometer, are continuously measured. Based on the emission levels during each mode and the total emission level obtained from the above test we can diagnose, not only the emission control systems of a vehicle and its engine conditions such as valve clearance maladjustment and carburetor defects, but also the emission characteristics of this vehicle.« less

Modeling study of natural emissions, source apportionment, and emission control of atmospheric mercury

NASA Astrophysics Data System (ADS)

Shetty, Suraj K.

Mercury (Hg) is a toxic pollutant and is important to understand its cycling in the environment. In this dissertation, a number of modeling investigations were conducted to better understand the emission from natural surfaces, the source-receptor relationship of the emissions, and emission reduction of atmospheric mercury. The first part of this work estimates mercury emissions from vegetation, soil and water surfaces using a number of natural emission processors and detailed (LAI) Leaf Area Index data from GIS (Geographic Information System) satellite products. East Asian domain was chosen as it contributes nearly 50% of the global anthropogenic mercury emissions into the atmosphere. The estimated annual natural mercury emissions (gaseous elemental mercury) in the domain are 834 Mg yr-1 with 462 Mg yr-1 contributing from China. Compared to anthropogenic sources, natural sources show greater seasonal variability (highest in simmer). The emissions are significant, sometimes dominant, contributors to total mercury emission in the regions. The estimates provide possible explanation for the gaps between the anthropogenic emission estimates based on activity data and the emission inferred from field observations in the regions. To understand the contribution of domestic emissions to mercury deposition in the United States, the second part of the work applies the mercury model of Community Multi-scale Air Quality Modeling system (CMAQ-Hg v4.6) to apportion the various emission sources attributing to the mercury wet and dry deposition in the 6 United States receptor regions. Contributions to mercury deposition from electric generating units (EGU), iron and steel industry (IRST), industrial point sources excluding EGU and IRST (OIPM), the remaining anthropogenic sources (RA), natural processes (NAT), and out-of-boundary transport (BC) in domain was estimated. The model results for 2005 compared reasonably well to field observations made by MDN (Mercury Deposition Network) and CAMNet (Canadian Atmospheric Mercury Measurement Network). The model estimated a total deposition of 474 Mg yr-1 to the CONUS (Contiguous United States) domain, with two-thirds being dry deposited. Reactive gaseous mercury contributed the most to 60% of deposition. Emission speciation distribution is a key factor for local deposition as contribution from large point sources can be as high as 75% near (< 100 km) the emission sources, indicating that emission reduction may result in direct deposition decrease near the source locations. Among the sources, BC contributes to about 68% to 91% of total deposition. Excluding the BC's contribution, EGU contributes to nearly 50% of deposition caused by CONUS emissions in the Northeast, Southeast and East Central regions, while emissions from natural processes are more important in the Pacific and West Central regions (contributing up to 40% of deposition). The modeling results implies that implementation of the new emission standards proposed by USEPA (United States Environmental Protection Agency) would significantly benefit regions that have larger contributions from EGU sources. Control of mercury emissions from coal combustion processes has attracted great attention due to its toxicity and the emission-control regulations and has lead to advancement in state-of-the-art control technologies that alleviate the impact of mercury on ecosystem and human health. This part of the work applies a sorption model to simulate adsorption of mercury in flue gases, onto a confined-bed of activated carbon. The model's performances were studied at various flue gas flow rates, inlet mercury concentrations and adsorption bed temperatures. The process simulated a flue gas, with inlet mercury concentration of 300 ppb, entering at a velocity of 0.3 m s-1 from the bottom into a fixed bed (inside bed diameter of 1 m and 3 m bed height; bed temperature of 25 °C) of activated carbon (particle size of 0.004 m with density of 0.5 g cm-3 and surface area of 90.25 cm2 g -1). The model result demonstrated that a batch of activated carbon bed was capable of controlling mercury emission for approximately 275 days after which further mercury uptake starts to decrease till it reaches about 500 days when additional control ceases. An increase in bed temperature significantly reduces mercury sorption capacity of the activated carbon. Increase in flue gas flow rate may result in faster consumption of sorption capacity initially but at a later stage, the sorption rate decreases due to reduced sorption capacity. Thus, overall sorption rate remains unaffected. The activated carbon's effective life (time to reach saturation) is not affected by inlet mercury concentration, implying that the designing and operation of a mercury sorption process can be done independently. The results provide quantitative indication for designing efficient confined-bed process to remove mercury from flue gases.

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

47 CFR 90.119 - Application requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... frequency, the station class, the total number of control stations, the emission, and the output power of... Services, including applications for new base, fixed, or mobile station authorizations governed by this part. (b) If the control station(s) will operate on the same frequency as the mobile station, and if...

Are closed landfills free of CH_{4} emissions? A case study of Arico's landfill, Tenerife, Canary Islands

NASA Astrophysics Data System (ADS)

Barrancos, José; Cook, Jenny; Phillips, Victoria; Asensio-Ramos, María; Melián, Gladys; Hernández, Pedro A.; Pérez, Nemesio M.

2016-04-01

Landfills are authentic chemical and biological reactors that introduce in the environment a wide amount of gas pollutants (CO2, CH4, volatile organic compounds, etc.) and leachates. Even after years of being closed, a significant amount of landfill gas could be released to the atmosphere through the surface in a diffuse form, also known as non-controlled emission. The study of the spatial-temporal distribution of diffuse emissions provides information of how a landfill degassing takes place. The main objective of this study was to estimate the diffuse uncontrolled emission of CH4 into the atmosphere from the closed Arico's landfill (0.3 km2) in Tenerife Island, Spain. To do so, a non-controlled biogenic gas emission survey of nearly 450 sampling sites was carried out during August 2015. Surface gas sampling and surface landfill CO2 efflux measurements were carried out at each sampling site by means of a portable non-dispersive infrared spectrophotometer (NDIR) model LICOR Li800 following the accumulation chamber method. Landfill gases, CO2 and CH4, were analyzed using a double channel VARIAN 4900 micro-GC. The CH4 efflux was computed combining CO2 efflux and CH4/CO2 ratio in the landfill's surface gas. To quantify the total CH4 emission, CH4 efflux contour map was constructed using sequential Gaussian simulation (sGs) as interpolation method. The total diffuse CH4 emission was estimated in 2.2 t d-1, with CH4 efflux values ranging from 0-922 mg m-2 d-1. This type of studies provides knowledge of how a landfill degasses and serves to public and private entities to establish effective systems for extraction of biogas. This aims not only to achieve higher levels of controlled gas release from landfills resulting in a higher level of energy production but also will contribute to minimize air pollution caused by them.

Identifying potential exposure reduction priorities using regional rankings based on emissions of known and suspected carcinogens to outdoor air in Canada.

PubMed

Setton, Eleanor M; Veerman, Basil; Erickson, Anders; Deschenes, Steeve; Cheasley, Roz; Poplawski, Karla; Demers, Paul A; Keller, C Peter

2015-08-22

Emissions inventories aid in understanding the sources of hazardous air pollutants and how these vary regionally, supporting targeted reduction actions. Integrating information on the relative toxicity of emitted pollutants with respect to cancer in humans helps to further refine reduction actions or recommendations, but few national programs exist in North America that use emissions estimates in this way. The CAREX Canada Emissions Mapping Project provides key regional indicators of emissions (total annual and total annual toxic equivalent, circa 2011) of 21 selected known and suspected carcinogens. The indicators were calculated from industrial emissions reported to the National Pollutant Release Inventory (NPRI) and estimates of emissions from transportation (airports, trains, and car and truck traffic) and residential heating (oil, gas and wood), in conjunction with human toxicity potential factors. We also include substance-specific annual emissions in toxic equivalent kilograms and annual emissions in kilograms, to allow for ranking substances within any region. For provinces and territories in Canada, the indicators suggest the top five substances contributing to the total toxic equivalent emissions in any region could be prioritized for further investigation. Residents of Quebec and New Brunswick may be more at risk of exposure to industrial emissions than those in other regions, suggesting that a more detailed study of exposure to industrial emissions in these provinces is warranted. Residential wood smoke may be an important emission to control, particularly in the north and eastern regions of Canada. Residential oil and gas heating, along with rail emissions contribute little to regional emissions and therefore may not be an immediate regional priority. The developed indicators support the identification of pollutants and sources for additional investigation when planning exposure reduction actions among Canadian provinces and territories, but have important limitations similar to other emissions inventory-based tools. Additional research is required to evaluate how the Emissions Mapping Project is used by different groups and organizations with respect to informing actions aimed at reducing Canadians' potential exposure to harmful air pollutants.

Municipal sludge composting facility emissions -- comparison of wet scrubber and biofiltration control performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holzman, M.I.; Gammie, L.A.; Gilbert, P.E.

1997-12-31

The Metropolitan District (MDC) Water Pollution Control Plant located in Hartford, Connecticut operates a state-of-the-art composting facility to process municipal sewage sludge. An air emissions test program was performed to determine emission rates of criteria and non-criteria pollutants and to evaluate the performance of two types of emissions/odor control systems (biofiltration and wet scrubbing). The purpose of this report is to further the limited available emissions and control performance data on a municipal sewage sludge composting facility operation. The MDC`s sludge composting facility consists of a Biocell train and a Cure Cell train, each of which can currently receive approximatelymore » 20 wet tons per hour of sludge at 60% of full capacity. The minimum retention time in each train is 10.5 days. Air emissions from the Biocell train are treated by both a biofiltration system and a three-stage wet scrubber system. The biofilter and wet scrubber system operate in parallel, so as to allow direct comparison of performance. Emissions from the Cure Cell train are treated by a single biofiltration system. The wet scrubber system consists of a first stage reducing absorber (ammonia solution), followed by a second stage oxidation absorber (sodium hypochlorite and sulfuric acid), and a final residual scrubber (sodium hydroxide solution). The two biofiltration systems are identically sized at 10,000 square feet surface area and three feet depth. The emissions testing program was designed to obtain simultaneous inlet and outlet data across each control device. The measured pollutants included organo-sulfides, alcohols, aldehydes, ketones, pinenes, terpenes, total reduced sulfur compounds, chlorinated hydrocarbons, sulfuric acid, sodium hydroxide, ammonia, carbon monoxide and volatile organic compounds.« less

India Co2 Emissions

NASA Astrophysics Data System (ADS)

Sharan, S.; Diffenbaugh, N. S.

2010-12-01

Is there a way to find a balance between improving living conditions for the people on the margins and also reducing emissions while limiting our negative impacts on the climate? This is a critical question today because there are many arguments between developed and developing countries about who is responsible for global warming. Developed countries believe that it is the poor countries because they are not educated enough to know about how they are affecting the climate. While the developing countries hold wealthy nations responsible because they are using the most resources. However it is important to acknowledge the fact that if there was no gap in between the developed and developing countries our emissions total would be much higher. This “gap” has been a natural controlling factor in climate change. This is why I wanted to see if I could plot what it would look like if a developing country such as India were to produce emissions that the US or Switzerland or Norway are producing as developed countries. India has a population total of 1.1 billion compared to the US with only 298 million, Switzerland with 7.5 million, and Norway with 4.6 million people. When the population is compared to the emissions output in metric tons, per capita, India produced the least emissions out of these countries, 1.4 tons per person while having the second largest population in the world, while the US produced 19 tons per capita, Switzerland produced 5.6 and Norway produced 8.7 tons per capita in 2006. The emissions rate is growing every year and increases widely and globally. If India was producing emissions that equal Norway, Switzerland and the US the total emissions it would be producing annually would be 9 billion for Norway, 6 billion for Switzerland and 20 billion emissions for the US, all in the year 2006 alone. This shows how the balance between countries with huge populations and very little emission output and average population and high emission out put has created a balance in between the “developed” and developing countries. If India was producing the same amounts of emissions per capita as the it would have a total of 20 billion metric tons of CO2 emissions annually.

Aerial Surveys of Elevated Hydrocarbon Emissions from Oil and Gas Production Sites.

PubMed

Lyon, David R; Alvarez, Ramón A; Zavala-Araiza, Daniel; Brandt, Adam R; Jackson, Robert B; Hamburg, Steven P

2016-05-03

Oil and gas (O&G) well pads with high hydrocarbon emission rates may disproportionally contribute to total methane and volatile organic compound (VOC) emissions from the production sector. In turn, these emissions may be missing from most bottom-up emission inventories. We performed helicopter-based infrared camera surveys of more than 8000 O&G well pads in seven U.S. basins to assess the prevalence and distribution of high-emitting hydrocarbon sources (detection threshold ∼ 1-3 g s(-1)). The proportion of sites with such high-emitting sources was 4% nationally but ranged from 1% in the Powder River (Wyoming) to 14% in the Bakken (North Dakota). Emissions were observed three times more frequently at sites in the oil-producing Bakken and oil-producing regions of mixed basins (p < 0.0001, χ(2) test). However, statistical models using basin and well pad characteristics explained 14% or less of the variance in observed emission patterns, indicating that stochastic processes dominate the occurrence of high emissions at individual sites. Over 90% of almost 500 detected sources were from tank vents and hatches. Although tank emissions may be partially attributable to flash gas, observed frequencies in most basins exceed those expected if emissions were effectively captured and controlled, demonstrating that tank emission control systems commonly underperform. Tanks represent a key mitigation opportunity for reducing methane and VOC emissions.

Effects of retrofitting emission control systems on in-use heavy diesel vehicles.

PubMed

Millstein, Dev E; Harley, Robert A

2010-07-01

Diesel engines are now the largest source of nitrogen oxides (NO(x)) and fine particulate black carbon (soot) emissions in California. The California Air Resources Board recently adopted a rule requiring that by 2014 all in-use heavy trucks and buses meet current (2007) exhaust particulate matter (PM) emission standards. Also by 2023 all in-use heavy-duty vehicles will have to meet current NO(x) emission standards, with significant progress in achieving the requirements for NO(x) control expected by 2014. This will require retrofit or replacement of older in-use engines. Diesel particle filters (DPF) reduce PM emissions but may increase the NO(2)/NO(x) emission ratio to approximately 35%, compared to approximately 5% typical of diesel engines without particle filters. Additionally, DPF with high oxidative capacity reduce CO and hydrocarbon emissions. We evaluate the effects of retrofitting trucks with DPF on air quality in southern California, using an Eulerian photochemical air quality model. Compared to a 2014 reference scenario without the retrofit program, black carbon concentrations decreased by 12 +/- 2% and 14 +/- 2% during summer and fall, respectively, with corresponding increases in ambient ozone concentrations of 3 +/- 2% and 7 +/- 3%. NO(2) concentrations decreased by 2-4% overall despite the increase in primary NO(2) emissions because total NO(x) emissions were reduced as part of the program to retrofit NO(x) control systems on in-use engines. However, in some cases NO(2) concentrations may increase at locations with high diesel truck traffic.

40 CFR 62.9601 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Allegheny County Bureau of Air Pollution Control submitted a letter on August 18, 1978 certifying that there.... 9, 1982, as amended at 50 FR 47735, Nov. 20, 1985] Total Reduced Sulfur Emissions From Existing...

40 CFR 62.6875 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

...—negative declaration. Letter from the Chief of the Air Pollution Control Division of the Department of... in the State of Nebraska. Total Reduced Sulfur Emissions From Existing Kraft Pulp Mills ...

40 CFR 62.6880 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Nebraska Total Reduced Sulfur Emissions from Existing Kraft Pulp Mills § 62.6880 Identification of plan—negative declaration. Letter from the Chief of the Air Pollution Control Division of the Department of...

40 CFR 62.9610 - Identification of plan-negative declaration

Code of Federal Regulations, 2010 CFR

2010-07-01

... Pennsylvania Total Reduced Sulfur Emissions from Existing Kraft Pulp Mills § 62.9610 Identification of plan—negative declaration (a) The Allegheny County Bureau of Air Pollution Control submitted a letter on...

Ammonia emissions from outdoor concrete yards used by livestock—quantification and mitigation

NASA Astrophysics Data System (ADS)

Misselbrook, T. H.; Webb, J.; Gilhespy, S. L.

Outdoor concrete yards are commonly found on UK livestock farms, and, to a lesser extent, elsewhere in Europe, and represent a potentially significant source of ammonia (NH 3) emissions to the atmosphere. This study provided further measurements from a larger sample than previously made, to improve the robustness of the estimate of total NH 3 emission for inclusion in the UK NH 3 emission inventory. In addition, an assessment was made of a number of potential mitigation strategies. Measurements were made using the equilibrium concentration technique, employing small dynamic chambers and passive diffusion samplers, from 20 yards used by livestock on commercial farms. Mean emission rates (±standard error) were 0.31±0.07, 0.23±0.12, 0.19±0.05 and 0.18±0.09 g NH 3-N m -2 h -1 (0.70±0.21, 0.53±0.34, 0.76±0.22 and 0.18±0.14 g NH 3-N animal -1 h -1) for dairy cow-collecting yards, dairy cow-feeding yards, beef-feeding yards and sheep-feeding/handling areas, respectively, with mean respective livestock densities of 0.3, 0.5, 0.2 and 1.1 animals per m 2. There was a significant effect of season, with lower emission rates in the winter. There was a significant, albeit poor, positive linear relationship between emission rate and ambient air temperature ( r2=0.22) and between emission rate and total ammoniacal N content on the yard surface ( r2=0.14), but not with ambient wind speed. Pooling data from the present study with that from previous studies gave mean emission factors of 0.47±0.09, 0.98±0.39 and 0.13±0.09 g NH 3-N animal -1 h -1 for yards used by dairy cattle, beef cattle and sheep, respectively. Inclusion of these values, together with survey data on yard use, gave a total annual UK emission of approximately 25 kt NH 3 (95% confidence interval of 12-40 kt NH 3), representing almost 10% of total NH 3 emission from UK agriculture. In controlled studies, pressure washing and the use of a urease inhibitor in addition to yard scraping were found to be effective means of reducing emissions compared with yard scraping alone. Reduction of yard area per animal was also an effective strategy to reduce total emissions.

Control of odor and VOC emissions at wastewater treatment plants: Boston Harbor case study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Getter, R.; Breen, C.; Laquidara, M.

1994-12-31

Siting of the new wastewater treatment plant (WWTP) for the Massachusetts Water Resources Authority (MWRA) in Boston was based on an assumption of mitigation of total reduced sulfur (TRS) and volatile organic compound (VOC) emissions. Collection and treatment of exhaust streams from potential emission sources was recommended. Best Available Control Technology (BACT) for VOC control was conservatively suggested to consist of wet by carbon adsorption based on initial sampling performed in 1988 during facilities planning, which estimated uncontrolled VOC emissions in excess of 1,000 tons per year. This concept was carried forward to the design phase in 1990, concurrent withmore » an extensive air emissions testing and pilot treatment program at the NMRA`s existing primary treatment plant. Results of the pilot program, however, indicated source VOC concentrations well below what was expected as a result of the initial sampling study. Use of the 1990 pilot data in a top-down BACT analysis led to a recommendation to reconsider VOC control with carbon adsorption on the basis of prohibitive cost. This paper summarizes the background and permitting approach for five new odor control facilities on Deer Island for the Boston Harbor Project, with emphasis on the new primary treatment facilities. The paper also presents results from the 1990 emissions characterization and pilot program, providing generally applicable ideas for solving the difficulties of characterizing and estimating emissions for WWTPS. Results from operation of the pilot facilities illustrate the effectiveness of met scrubbing and carbon adsorption in removing TRS and VOCs from wastewater treatment exhaust air streams. In addition, pilot program results indicate the importance of flexibility in design of odor control systems to accommodate variations in concentrations of TRS and VOCS.« less

Audible acoustics in high-shear wet granulation: application of frequency filtering.

PubMed

Hansuld, Erin M; Briens, Lauren; McCann, Joe A B; Sayani, Amyn

2009-08-13

Previous work has shown analysis of audible acoustic emissions from high-shear wet granulation has potential as a technique for end-point detection. In this research, audible acoustic emissions (AEs) from three different formulations were studied to further develop this technique as a process analytical technology. Condenser microphones were attached to three different locations on a PMA-10 high-shear granulator (air exhaust, bowl and motor) to target different sound sources. Size, flowability and tablet break load data was collected to support formulator end-point ranges and interpretation of AE analysis. Each formulation had a unique total power spectral density (PSD) profile that was sensitive to granule formation and end-point. Analyzing total PSD in 10 Hz segments identified profiles with reduced run variability and distinct maxima and minima suitable for routine granulation monitoring and end-point control. A partial least squares discriminant analysis method was developed to automate selection of key 10 Hz frequency groups using variable importance to projection. The results support use of frequency refinement as a way forward in the development of acoustic emission analysis for granulation monitoring and end-point control.

Measurement of CO 2, CO, SO 2, and NO emissions from coal-based thermal power plants in India

NASA Astrophysics Data System (ADS)

Chakraborty, N.; Mukherjee, I.; Santra, A. K.; Chowdhury, S.; Chakraborty, S.; Bhattacharya, S.; Mitra, A. P.; Sharma, C.

Measurements of CO 2 (direct GHG) and CO, SO 2, NO (indirect GHGs) were conducted on-line at some of the coal-based thermal power plants in India. The objective of the study was three-fold: to quantify the measured emissions in terms of emission coefficient per kg of coal and per kWh of electricity, to calculate the total possible emission from Indian thermal power plants, and subsequently to compare them with some previous studies. Instrument IMR 2800P Flue Gas Analyzer was used on-line to measure the emission rates of CO 2, CO, SO 2, and NO at 11 numbers of generating units of different ratings. Certain quality assurance (QA) and quality control (QC) techniques were also adopted to gather the data so as to avoid any ambiguity in subsequent data interpretation. For the betterment of data interpretation, the requisite statistical parameters (standard deviation and arithmetic mean) for the measured emissions have been also calculated. The emission coefficients determined for CO 2, CO, SO 2, and NO have been compared with their corresponding values as obtained in the studies conducted by other groups. The total emissions of CO 2, CO, SO 2, and NO calculated on the basis of the emission coefficients for the year 2003-2004 have been found to be 465.667, 1.583, 4.058, and 1.129 Tg, respectively.

Meteorological Controls on Biomass Burning During Santa Ana Events in Southern California

NASA Technical Reports Server (NTRS)

Veraverbeke, Sander; Capps, Scott; Hook, Simon J.; Randerson, James T.; Jin, Yufang; Hall, Alex

2013-01-01

Fires occurring during Santa Ana (SA) events in southern California are driven by extreme fire weather characterized by high temperatures, low humidities, and high wind speeds. We studied the controls on burned area and carbon emissions during two intensive SA burning periods in 2003 and 2007. We therefore used remote sensing data in parallel with fire weather simulations of the Weather and Regional Forecast model. Total carbon emissions were approximately 1800 gigagrams in 2003 and 900 gigagrams in 2007, based on a daily burned area and a fire emission model that accounted for spatial variability in fuel loads and combustion completeness. On a regional scale, relatively strong positive correlations were found between the daily Fosberg fire weather index and burned area/emissions (probability is less than 0.01). Our analysis provides a quantitative assessment of relationships between fire activity and weather during severe SA fires in southern California.

Inverse modeling and mapping US air quality influences of inorganic PM2.5 precursor emissions using the adjoint of GEOS-Chem

NASA Astrophysics Data System (ADS)

Henze, D. K.; Seinfeld, J. H.; Shindell, D. T.

2009-08-01

Influences of specific sources of inorganic PM2.5 on peak and ambient aerosol concentrations in the US are evaluated using a combination of inverse modeling and sensitivity analysis. First, sulfate and nitrate aerosol measurements from the IMPROVE network are assimilated using the four-dimensional variational (4D-Var) method into the GEOS-Chem chemical transport model in order to constrain emissions estimates in four separate month-long inversions (one per season). Of the precursor emissions, these observations primarily constrain ammonia (NH3). While the net result is a decrease in estimated US~NH3 emissions relative to the original inventory, there is considerable variability in adjustments made to NH3 emissions in different locations, seasons and source sectors, such as focused decreases in the midwest during July, broad decreases throughout the US~in January, increases in eastern coastal areas in April, and an effective redistribution of emissions from natural to anthropogenic sources. Implementing these constrained emissions, the adjoint model is applied to quantify the influences of emissions on representative PM2.5 air quality metrics within the US. The resulting sensitivity maps display a wide range of spatial, sectoral and seasonal variability in the susceptibility of the air quality metrics to absolute emissions changes and the effectiveness of incremental emissions controls of specific source sectors. NH3 emissions near sources of sulfur oxides (SOx) are estimated to most influence peak inorganic PM2.5 levels in the East; thus, the most effective controls of NH3 emissions are often disjoint from locations of peak NH3 emissions. Controls of emissions from industrial sectors of SOx and NOx are estimated to be more effective than surface emissions, and changes to NH3 emissions in regions dominated by natural sources are disproportionately more effective than regions dominated by anthropogenic sources. NOx controls are most effective in northern states in October; in January, SOx controls may be counterproductive. When considering ambient inorganic PM2.5 concentrations, intercontinental influences are small, though transboundary influences within North America are significant, with SOx emissions from surface sources in Mexico contributing almost a fourth of the total influence from this sector.

Inverse modeling and mapping US air quality influences of inorganic PM2.5 precursor emissions using the adjoint of GEOS-Chem

NASA Astrophysics Data System (ADS)

Henze, D. K.; Seinfeld, J. H.; Shindell, D. T.

2008-08-01

Influences of specific sources of inorganic PM2.5 on peak and ambient aerosol concentrations in the US are evaluated using a combination of inverse modeling and sensitivity analysis. First, sulfate and nitrate aerosol measurements from the IMPROVE network are assimilated using the four-dimensional variational (4D-Var) method into the GEOS-Chem chemical transport model in order to constrain emissions estimates in four separate month-long inversions (one per season). Of the precursor emissions, these observations primarily constrain ammonia (NH3). While the net result is a decrease in estimated US NH3 emissions relative to the original inventory, there is considerable variability in adjustments made to NH3 emissions in different locations, seasons and source sectors, such as focused decreases in the midwest during July, broad decreases throughout the US~in January, increases in eastern coastal areas in April, and an effective redistribution of emissions from natural to anthropogenic sources. Implementing these constrained emissions, the adjoint model is applied to quantify the influences of emissions on representative PM2.5 air quality metrics within the US. The resulting sensitivity maps display a wide range of spatial, sectoral and seasonal variability in the susceptibility of the air quality metrics to absolute emissions changes and the effectiveness of incremental emissions controls of specific source sectors. NH3 emissions near sources of sulfur oxides (SOx) are estimated to most influence peak inorganic PM2.5 levels in the East; thus, the most effective controls of NH3 emissions are often disjoint from locations of peak NH3 emissions. Controls of emissions from industrial sectors of SOx and NOx are estimated to be more effective than surface emissions, and changes to NH3 emissions in regions dominated by natural sources are disproportionately more effective than regions dominated by anthropogenic sources. NOx controls are most effective in northern states in October; in January, SOx controls may be counterproductive. When considering ambient inorganic PM2.5 concentrations, intercontinental influences are small, though transboundary influences within North America are significant, with SOx emissions from surface sources in Mexico contributing almost a fourth of the total influence from this sector.

[Measurement model of carbon emission from forest fire: a review].

PubMed

Hu, Hai-Qing; Wei, Shu-Jing; Jin, Sen; Sun, Long

2012-05-01

Forest fire is the main disturbance factor for forest ecosystem, and an important pathway of the decrease of vegetation- and soil carbon storage. Large amount of carbonaceous gases in forest fire can release into atmosphere, giving remarkable impacts on the atmospheric carbon balance and global climate change. To scientifically and effectively measure the carbonaceous gases emission from forest fire is of importance in understanding the significance of forest fire in the carbon balance and climate change. This paper reviewed the research progress in the measurement model of carbon emission from forest fire, which covered three critical issues, i. e., measurement methods of forest fire-induced total carbon emission and carbonaceous gases emission, affecting factors and measurement parameters of measurement model, and cause analysis of the uncertainty in the measurement of the carbon emissions. Three path selections to improve the quantitative measurement of the carbon emissions were proposed, i. e., using high resolution remote sensing data and improving algorithm and estimation accuracy of burned area in combining with effective fuel measurement model to improve the accuracy of the estimated fuel load, using high resolution remote sensing images combined with indoor controlled environment experiments, field measurements, and field ground surveys to determine the combustion efficiency, and combining indoor controlled environment experiments with field air sampling to determine the emission factors and emission ratio.

Nitrogen oxides emissions from thermal power plants in china: current status and future predictions.

PubMed

Tian, Hezhong; Liu, Kaiyun; Hao, Jiming; Wang, Yan; Gao, Jiajia; Qiu, Peipei; Zhu, Chuanyong

2013-10-01

Increasing emissions of nitrogen oxides (NOx) over the Chinese mainland have been of great concern due to their adverse impacts on regional air quality and public health. To explore and obtain the temporal and spatial characteristics of NOx emissions from thermal power plants in China, a unit-based method is developed. The method assesses NOx emissions based on detailed information on unit capacity, boiler and burner patterns, feed fuel types, emission control technologies, and geographical locations. The national total NOx emissions in 2010 are estimated at 7801.6 kt, of which 5495.8 kt is released from coal-fired power plant units of considerable size between 300 and 1000 MW. The top provincial emitter is Shandong where plants are densely concentrated. The average NOx-intensity is estimated at 2.28 g/kWh, markedly higher than that of developed countries, mainly owing to the inadequate application of high-efficiency denitrification devices such as selective catalytic reduction (SCR). Future NOx emissions are predicted by applying scenario analysis, indicating that a reduction of about 40% by the year 2020 can be achieved compared with emissions in 2010. These results suggest that NOx emissions from Chinese thermal power plants could be substantially mitigated within 10 years if reasonable control measures were implemented effectively.

Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production.

PubMed

Pujol Pereira, Engil Isadora; Suddick, Emma C; Six, Johan

2016-01-01

By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct CO2 and nitrous oxide (N2O) emissions from soil. The objective of these assessments was to pinpoint where the largest C offsets can be expected in the bioenergy-biochar chain. We found that energy production from gasification resulted in 91.8% of total C offsets, followed by stable biochar-C (8.2% of total C sinks), offsetting a total of 107.7 kg CO2-C eq Mg-1 feedstock. At the field scale, we monitored gas fluxes from soils for 29 months (180 individual observations) following field management and precipitation events in addition to weekly measurements within three growing seasons and two tree dormancy periods. We compared four treatments: control, biochar, compost, and biochar combined with compost. Biochar alone or in combination with compost did not alter total N2O and CO2 emissions from soils, indicating that under the conditions of this study, biochar-prompted C offsets may not be expected from the mitigation of direct soil GHG emissions. However, this study revealed a case where a large environmental benefit was given by the waste-to-bioenergy treatment, addressing farm level challenges such as waste management, renewable energy generation, and C sequestration.

Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production

PubMed Central

Pujol Pereira, Engil Isadora; Suddick, Emma C.; Six, Johan

2016-01-01

By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct CO2 and nitrous oxide (N2O) emissions from soil. The objective of these assessments was to pinpoint where the largest C offsets can be expected in the bioenergy-biochar chain. We found that energy production from gasification resulted in 91.8% of total C offsets, followed by stable biochar-C (8.2% of total C sinks), offsetting a total of 107.7 kg CO2-C eq Mg-1 feedstock. At the field scale, we monitored gas fluxes from soils for 29 months (180 individual observations) following field management and precipitation events in addition to weekly measurements within three growing seasons and two tree dormancy periods. We compared four treatments: control, biochar, compost, and biochar combined with compost. Biochar alone or in combination with compost did not alter total N2O and CO2 emissions from soils, indicating that under the conditions of this study, biochar-prompted C offsets may not be expected from the mitigation of direct soil GHG emissions. However, this study revealed a case where a large environmental benefit was given by the waste-to-bioenergy treatment, addressing farm level challenges such as waste management, renewable energy generation, and C sequestration. PMID:26963623

Updated atmospheric speciated mercury emissions from iron and steel production in China during 2000-2015

NASA Astrophysics Data System (ADS)

Wu, Qingru; Gao, Wei; Wang, Shuxiao; Hao, Jiming

2017-09-01

Iron and steel production (ISP) is one of the significant atmospheric Hg emission sources in China. Atmospheric mercury (Hg) emissions from ISP during 2000-2015 were estimated by using a technology-based emission factor method. To support the application of this method, databases of Hg concentrations in raw materials, technology development trends, and Hg removal efficiencies of air pollution control devices (APCDs) were constructed through national sampling and literature review. Hg input to ISP increased from 21.6 t in 2000 to 94.5 t in 2015. In the various types of raw materials, coking coal and iron concentrates contributed 35-46 and 25-32 % of the total Hg input. Atmospheric Hg emissions from ISP increased from 11.5 t in 2000 to 32.7 t in 2015 with a peak of 35.6 t in 2013. Pollution control promoted the increase in average Hg removal efficiency, from 47 % in 2000 to 65 % in 2015. During the study period, sinter/pellet plants and blast furnaces were the largest two emission processes. However, emissions from roasting plants and coke ovens cannot be ignored, which accounted for 22-34 % of ISP's emissions. Overall, Hg speciation shifted from 50/44/6 (gaseous elemental Hg (Hg0)/gaseous oxidized Hg (HgII)/particulate-bound Hg (Hgp)) in 2000 to 40/59/1 in 2015, which indicated a higher proportion of Hg deposition around the emission points. Future emissions of ISP were expected to decrease based on the comprehensive consideration crude-steel production, steel scrap utilization, energy saving, and pollution control measures.

Effects of different types of biochar on methane and ammonia mitigation during layer manure composting.

PubMed

Chen, Wei; Liao, Xindi; Wu, Yinbao; Liang, Juan Boo; Mi, Jiandui; Huang, Jinjie; Zhang, Heng; Wu, Yu; Qiao, Zhifen; Li, Xi; Wang, Yan

2017-03-01

Biochar, because of its unique physiochemical properties and sorption capacity, may be an ideal amendment in reducing gaseous emissions during composting process but there has been little information on the potential effects of different types of biochar on undesired gaseous emissions. The objective of this study was to examine the ability and mechanism of different types of biochar, as co-substrate, in mitigating gaseous emission from composting of layer hen manure. The study was conducted in small-scale laboratory composters with the addition of 10% of one of the following biochars: cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar. The results showed that the cumulative NH 3 production was significantly reduced by 24.8±2.9, 9.2±1.3, 20.1±2.6, 14.2±1.6, 11.8±1.7% (corrected for initial total N) in the cornstalk biochar, bamboo biochar, woody biochar, layer manure biochar and coir biochar treatments, respectively, compared to the control. Total CH 4 emissions was significantly reduced by 26.1±2.3, 15.5±2.1, 22.4±3.1, 17.1±2.1% (corrected for the initial total carbon) for cornstalk biochar, bamboo biochar, woody biochar and coir biochar treatments than the control. Moreover, addition of cornstalk biochar increased the temperature and NO 3 - -N concentration and decreased the pH, NH 4 + -N and organic matter content throughout the composting process. The results suggested that total volatilization of NH 3 and CH 4 in cornstalk biochar treatment was lower than the other treatments; which could be due to (i) decrease of pH and higher nitrification, (ii) high sorption capacity for gases and their precursors, such as ammonium nitrogen from composting mixtures, because of the higher surface area, pore volumes, total acidic functional groups and CEC of cornstalk biochar. Copyright © 2017 Elsevier Ltd. All rights reserved.

Environmental assessment of a wood-waste-fired industrial watertube boiler. Volume 1. Technical results. Final report, March 1981-March 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castaldini, C.; Waterland, L.R.

1987-03-01

The two-volume report gives results from field tests of a wood-waste-fired industrial watertube boiler. Two series of tests were performed: one firing dry (11% moisture) wood waste, and the other firing green (34% moisture) wood waste. Emission measurements included: continuous monitoring of flue-gas emissions; source-assessment sampling system (SASS) sampling of the flue gas with subsequent laboratory analysis of samples to give total flue-gas organics in two boiling-point ranges, compound category information within these ranges, specific quantitation of the semi-volatile organic priority pollutants, and flue-gas concentrations of 73 trace elements; Method 5 sampling for particulate; controlled condensation system sampling for SO/submore » 2/ and SO/sub 3/; and grab sampling of boiler mechanical collector hopper ash for inorganic composition determinations. Total organic emissions decreased from 60-135 mg/dscm firing dry wood to 2-65 mg/dscm firing green wood, in parallel with corresponding boiler CO emissions.« less

Environmental assessment of a wood-waste-fired industrial watertube boiler. Volume 2. Data supplement. Final report, March 1981-March 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Castaldini, C.; Waterland, L.R.

1987-03-01

The two-volume report gives results from field tests of a wood-waste-fired industrial watertube boiler. Two series of tests were performed: one firing dry (11% moisture) wood waste, and the other firing green (34% moisture) wood waste. Emission measurements included: continuous monitoring of flue-gas emissions; source-assessment sampling system (SASS) sampling of the flue-gas with subsequent laboratory analysis of samples to give total flue-gas organics in two boiling-point ranges, compound category information within these ranges, specific quantitation of the semi-volatile organic priority pollutants, and flue gas concentrations of 73 trace elements; Method 5 sampling for particulate; controlled condensation system sampling for SO/submore » 2/ and SO/sub 3/; and grab sampling of boiler mechanical collector hopper ash for inorganic and organic composition determinations. Total organic emissions decreased from 60-135 mg/dscm firing dry wood to 2-65 mg/dscm firing green wood, in parallel with corresponding boiler CO emissions.« less

Effect of process parameters on greenhouse gas generation by wastewater treatment plants.

PubMed

Yerushalmi, L; Shahabadi, M Bani; Haghighat, F

2011-05-01

The effect of key process parameters on greenhouse gas (GHG) emission by wastewater treatment plants was evaluated, and the governing parameters that exhibited major effects on the overall on- and off-site GHG emissions were identified. This evaluation used aerobic, anaerobic, and hybrid anaerobic/aerobic treatment systems with food processing industry wastewater. The operating temperature of anaerobic sludge digester was identified to have the highest effect on GHG generation in the aerobic treatment system. The total GHG emissions of 2694 kg CO2e/d were increased by 72.5% with the increase of anaerobic sludge digester temperature from 20 to 40 degrees C. The operating temperature of the anaerobic reactor was the dominant controlling parameter in the anaerobic and hybrid treatment systems. Raising the anaerobic reactor's temperature from 25 to 40 degrees C increased the total GHG emissions from 5822 and 6617 kg CO2e/d by 105.6 and 96.5% in the anaerobic and hybrid treatment systems, respectively.

40 CFR 52.2054 - Control of asphalt paving material.

Code of Federal Regulations, 2010 CFR

2010-07-01

... work on roadways and shoulders; and (3) No more than 2,500,000 gallons total of emulsion Class E-4 and... additional hydrocarbon emissions from emulsions. (b) The Pennsylvania Department of Transportation is...

40 CFR 52.2054 - Control of asphalt paving material.

Code of Federal Regulations, 2013 CFR

2013-07-01

... work on roadways and shoulders; and (3) No more than 2,500,000 gallons total of emulsion Class E-4 and... additional hydrocarbon emissions from emulsions. (b) The Pennsylvania Department of Transportation is...

40 CFR 52.2054 - Control of asphalt paving material.

Code of Federal Regulations, 2011 CFR

2011-07-01

... work on roadways and shoulders; and (3) No more than 2,500,000 gallons total of emulsion Class E-4 and... additional hydrocarbon emissions from emulsions. (b) The Pennsylvania Department of Transportation is...

40 CFR 52.2054 - Control of asphalt paving material.

Code of Federal Regulations, 2014 CFR

2014-07-01

... work on roadways and shoulders; and (3) No more than 2,500,000 gallons total of emulsion Class E-4 and... additional hydrocarbon emissions from emulsions. (b) The Pennsylvania Department of Transportation is...

40 CFR 52.2054 - Control of asphalt paving material.

Code of Federal Regulations, 2012 CFR

2012-07-01

... work on roadways and shoulders; and (3) No more than 2,500,000 gallons total of emulsion Class E-4 and... additional hydrocarbon emissions from emulsions. (b) The Pennsylvania Department of Transportation is...

40 CFR 62.6121 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

...—negative declaration. The Mississippi Bureau of Pollution Control submitted on March 6, 1985, a letter..., subpart B of this chapter. [50 FR 26204, June 25, 1985] Total Reduced Sulfur Emissions From Kraft Pulp...

Impacts of continuously regenerating trap and particle oxidation catalyst on the NO2 and particulate matter emissions emitted from diesel engine.

PubMed

Liu, Zhihua; Ge, Yunshan; Tan, Jianwei; He, Chao; Shah, Asad Naeem; Ding, Yan; Yu, Linxiao; Zhao, Wei

2012-01-01

Two continuously regenerating diesel particulate filter (CRDPF) with different configurations and one particles oxidation catalyst (POC) were employed to perform experiments in a controlled laboratory setting to evaluate their effects on NO2, smoke and particle number emissions. The results showed that the application of the after-treatments increased the emission ratios of NO2/NOx significantly. The results of smoke emissions and particle number (PN) emissions indicated that both CRDPFs had sufficient capacity to remove more than 90% of total particulate matter (PM) and more than 97% of solid particles. However, the POC was able to remove the organic components of total PM, and only partially to remove the carbonaceous particles with size less than 30 nm. The negligible effects of POC on larger particles were observed due to its honeycomb structure leads to an inadequate residence time to oxidize the solid particles or trap them. The particles removal efficiencies of CRDPFs had high degree of correlations with the emission ratio of NO2/NOx. The PN emission results from two CRDPFs indicated that more NO2 generating in diesel oxidation catalyst section could obtain the higher removal efficiency of solid particles. However this also increased the risk of NO2 exposure in atmosphere.

Investigating Electrostatic Precipitator Design Parameters for Efficient Control of Particulate Matter in Thermal Power Plant: A Case Study

NASA Astrophysics Data System (ADS)

Rai, P.; Gautam, N.; Chandra, H.

2018-06-01

This work deals with the analysis and modification of operational parameters for meeting the emission standards, set by Central Pollution Control Board (CPCB)/State Pollution Control Board (SPCB) from time to time of electrostatic precipitator (ESP). The analysis is carried out by using standard chemical analysis supplemented by the relevant data collected from Korba East Phase (Ph)-III thermal power plant, under Chhattisgarh State Electricity Board (CSEB) operating at Korba, Chhattisgarh. Chemical analysis is used to predict the emission level for different parameters of ESP. The results reveal that for a constant outlet PM concentration and fly ash percentage, the total collection area decreases with the increase in migration velocity. For constant migration velocity and outlet PM concentration, the total collection area increases with the increase in the fly ash percent. For constant migration velocity and outlet e PM concentration, the total collection area increases with the ash content in the coal. i.e. from minimum ash to maximum ash. As far as the efficiency is concerned, it increases with the fly ash percent, ash content and the inlet dust concentration but decreases with the outlet PM concentration at constant migration velocity, fly ash and ash content.

Investigating Electrostatic Precipitator Design Parameters for Efficient Control of Particulate Matter in Thermal Power Plant: A Case Study

NASA Astrophysics Data System (ADS)

Rai, P.; Gautam, N.; Chandra, H.

2018-02-01

This work deals with the analysis and modification of operational parameters for meeting the emission standards, set by Central Pollution Control Board (CPCB)/State Pollution Control Board (SPCB) from time to time of electrostatic precipitator (ESP). The analysis is carried out by using standard chemical analysis supplemented by the relevant data collected from Korba East Phase (Ph)-III thermal power plant, under Chhattisgarh State Electricity Board (CSEB) operating at Korba, Chhattisgarh. Chemical analysis is used to predict the emission level for different parameters of ESP. The results reveal that for a constant outlet PM concentration and fly ash percentage, the total collection area decreases with the increase in migration velocity. For constant migration velocity and outlet PM concentration, the total collection area increases with the increase in the fly ash percent. For constant migration velocity and outlet e PM concentration, the total collection area increases with the ash content in the coal. i.e. from minimum ash to maximum ash. As far as the efficiency is concerned, it increases with the fly ash percent, ash content and the inlet dust concentration but decreases with the outlet PM concentration at constant migration velocity, fly ash and ash content.

Effects of woody peat and superphosphate on compost maturity and gaseous emissions during pig manure composting.

PubMed

Zhang, Difang; Luo, Wenhai; Yuan, Jing; Li, Guoxue; Luo, Yuan

2017-10-01

This study investigated the effect of calcium superphosphate on compost maturity and gaseous emissions during pig manure composting with woody peat as the bulking agent. Two treatments were conducted with or without the addition of calcium superphosphate (10% dry weight of the composting mass), which were denoted as the control and superphosphate-amended treatment, respectively. Results show that the composting temperature of both treatments was higher than 50°C for more than 5days, which is typically required for pathogen destruction during manure composting. Compared to the control treatment, the superphosphate-amended treatment increased the emission of nitrogen oxide, but reduced the emission of methane, ammonia and hydrogen sulfide by approximately 35.5%, 37.9% and 65.5%, respectively. As a result, the total greenhouse gas (GHG) emission during manure composting was reduced by nearly 34.7% with the addition of calcium superphosphate. The addition of calcium superphosphate increased the content of humic acid (indicated by E 4 /E 6 ratio). Nevertheless, the superphosphate-amended treatment postponed the biological degradation of organic matter and produced the mature compost with a higher electrical conductivity in comparison with the control treatment. Copyright © 2017. Published by Elsevier Ltd.

Evolution of Submicrometer Organic Aerosols during a Complete Residential Coal Combustion Process.

PubMed

Zhou, Wei; Jiang, Jingkun; Duan, Lei; Hao, Jiming

2016-07-19

In the absence of particulate matter (PM) control devices, residential coal combustion contributes significantly to ambient PM pollution. Characterizing PM emissions from residential coal combustion with high time resolution is beneficial for developing control policies and evaluating the environmental impact of PM. This study reports the evolution of submicrometer organic aerosols (OA) during a complete residential coal combustion process, that is, from fire start to fire extinction. Three commonly used coal types (bituminous, anthracite, and semicoke coals) were evaluated in a typical residential stove in China. For all three types of coal, the OA emission exhibited distinct characteristics in the four stages, that is, ignition, fierce combustion, relatively stable combustion, and ember combustion. OA emissions during the ignition stage accounted for 58.2-85.4% of the total OA emission of a complete combustion process. The OA concentration decreased rapidly during the fierce combustion stage and remained low during the relatively stable combustion stage. During these two stages, a significant ion peak of m/z 73 from organic acids were observed. The degree of oxidation of the OA increased from the first stage to the last stage. Implications for ambient OA source-apportionment and residential PM emission characterization and control are discussed.

Joint Optimization of Distribution Network Design and Two-Echelon Inventory Control with Stochastic Demand and CO2 Emission Tax Charges.

PubMed

Li, Shuangyan; Li, Xialian; Zhang, Dezhi; Zhou, Lingyun

2017-01-01

This study develops an optimization model to integrate facility location and inventory control for a three-level distribution network consisting of a supplier, multiple distribution centers (DCs), and multiple retailers. The integrated model addressed in this study simultaneously determines three types of decisions: (1) facility location (optimal number, location, and size of DCs); (2) allocation (assignment of suppliers to located DCs and retailers to located DCs, and corresponding optimal transport mode choices); and (3) inventory control decisions on order quantities, reorder points, and amount of safety stock at each retailer and opened DC. A mixed-integer programming model is presented, which considers the carbon emission taxes, multiple transport modes, stochastic demand, and replenishment lead time. The goal is to minimize the total cost, which covers the fixed costs of logistics facilities, inventory, transportation, and CO2 emission tax charges. The aforementioned optimal model was solved using commercial software LINGO 11. A numerical example is provided to illustrate the applications of the proposed model. The findings show that carbon emission taxes can significantly affect the supply chain structure, inventory level, and carbon emission reduction levels. The delay rate directly affects the replenishment decision of a retailer.

Mitigation of N2O Emission from Aquaponics by Optimizing the Nitrogen Transformation Process: Aeration Management and Exogenous Carbon (PLA) Addition.

PubMed

Zou, Yina; Hu, Zhen; Zhang, Jian; Fang, Yingke; Li, Minying; Zhang, Jianda

2017-10-11

N 2 O production in aquaponics is an inevitable concern when aquaponics is developed as a future production system. In the present study, two attempts were applied to mitigate N 2 O emission from aquaponics, i.e., aeration in hydroponic bed (HA) and addition of polylactic acid (PLA) into fillers (PA). Results showed that N 2 O emission from HA and PA was decreased by 47.1-58.1% and 43.2-74.9% respectively compared with that in control. Denitrification was proved to be the main emission pathway in all treatments, representing 62.4%, 86.4%, and 75.8% of the total N 2 O emission in HA, PA, and control, respectively. However, production of plants in HA was severely impaired, which was only 3.04 ± 0.39 kg/m 2 , while in PA and control, plants yields were 4.87 ± 0.56 kg/m 2 and 4.33 ± 0.58 kg/m 2 . Combining the environmental and economic benefits, adding PLA in aquaponics may have a better future when developing and applying aquaponics systems.

Reduction and prediction of N2O emission from an Anoxic/Oxic wastewater treatment plant upon DO control and model simulation.

PubMed

Sun, Shichang; Bao, Zhiyuan; Li, Ruoyu; Sun, Dezhi; Geng, Haihong; Huang, Xiaofei; Lin, Junhao; Zhang, Peixin; Ma, Rui; Fang, Lin; Zhang, Xianghua; Zhao, Xuxin

2017-11-01

In order to make a better understanding of the characteristics of N 2 O emission in A/O wastewater treatment plant, full-scale and pilot-scale experiments were carried out and a back propagation artificial neural network model based on the experimental data was constructed to make a precise prediction of N 2 O emission. Results showed that, N 2 O flux from different units followed a descending order: aerated grit tank>oxic zone≫anoxic zone>final clarifier>primary clarifier, but 99.4% of the total emission of N 2 O (1.60% of N-load) was monitored from the oxic zone due to its big surface area. A proper DO control could reduce N 2 O emission down to 0.21% of N-load in A/O process, and a two-hidden-layers back propagation model with an optimized structure of 4:3:9:1 could achieve a good simulation of N 2 O emission, which provided a new method for the prediction of N 2 O emission during wastewater treatment. Copyright © 2017. Published by Elsevier Ltd.

40 CFR 63.6620 - What performance tests and other procedures must I use?

Code of Federal Regulations, 2014 CFR

2014-07-01

... Where: Ci = concentration of carbon monoxide (CO), total hydrocarbons (THC), or formaldehyde at the control device inlet, Co = concentration of CO, THC, or formaldehyde at the control device outlet, and R = percent reduction of CO, THC, or formaldehyde emissions. (2) You must normalize the CO, THC, or...

40 CFR 63.6620 - What performance tests and other procedures must I use?

Code of Federal Regulations, 2013 CFR

2013-07-01

... Where: Ci = concentration of carbon monoxide (CO), total hydrocarbons (THC), or formaldehyde at the control device inlet, Co = concentration of CO, THC, or formaldehyde at the control device outlet, and R = percent reduction of CO, THC, or formaldehyde emissions. (2) You must normalize the CO, THC, or...

40 CFR 1051.5 - Which engines are excluded from this part's requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... engines. (2) Vehicles with a combined total vehicle dry weight under 20.0 kilograms are excluded from this... (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM RECREATIONAL ENGINES AND VEHICLES Overview and Applicability § 1051.5 Which engines are excluded from this part's requirements? (a)(1) You may exclude vehicles...

Optimization of heavy metals total emission, case study: Bor (Serbia)

NASA Astrophysics Data System (ADS)

Ilić, Ivana; Bogdanović, Dejan; Živković, Dragana; Milošević, Novica; Todorović, Boban

2011-07-01

The town of Bor (Serbia) is one of the most polluted towns in southeastern Europe. The copper smelter which is situated in the centre of the town is the main pollutant, mostly because of its old technology, which leads to environmental pollution caused by higher concentrations of SO 2 and PM 10. These facts show that the word is about a very polluted region in Europe which, apart from harming human health in the region itself, poses a particular danger for wider area of southeastern Europe. Optimization of heavy metal's total emission was undertaken because years of long contamination of the soil with heavy metals of anthropogenic origin created a danger that those heavy metals may enter the food chains of animals and people, which can lead to disastrous consequences. This work represents the usage of Geographic Information System (GIS) for establishing a multifactor assessment model to quantitatively divide polluted zones and for selecting control sites in a linear programming model, combined with PROMETHEE/GAIA method, Screen View modeling system, and linear programming model. The results show that emissions at some control sites need to be cut for about 40%. In order to control the background of heavy metal pollution in Bor, the ecological environment must be improved.

Unanticipated benefits of automotive emission control: reduction in fatalities by motor vehicle exhaust gas.

PubMed

Shelef, M

1994-05-23

In 1970, before the implementation of strict controls on emissions in motor vehicle exhaust gas (MVEG), the annual USA incidence of fatal accidents by carbon monoxide in the MVEG was approximately 800 and that of suicides approximately 2000 (somewhat less than 10% of total suicides). In 1987, there were approximately 400 fatal accidents and approximately 2700 suicides by MVEG. Accounting for the growth in population and vehicle registration, the yearly lives saved in accidents by MVEG were approximately 1200 in 1987 and avoided suicides approximately 1400. The decrease in accidents continues unabated while the decrease in expected suicides by MVEG reached a plateau in 1981-1983. The reasons for this disparity are discussed. Juxtaposition of these results with the projected cancer risk avoidance of less than 500 annually in 2005 (as compared with 1986) plainly shows that, in terms of mortality, the unanticipated benefits of emission control far overshadow the intended benefits. With the spread of MVEG control these benefits will accrue worldwide.

A Simple But Comprehensive Methodology To Determine Gas-Phase Emissions Of Motor Vehicles With Extractive FTIR Spectrometry

NASA Astrophysics Data System (ADS)

Reyes, F. M.; Jaczilevich, A.; Grutter, M. A.; Huerta, M. A.; Rincón, P.; Rincón, R.; González, R.

2004-12-01

In this contribution, a methodology to acquire valuable information on the chemical composition and evolution of vehicular emissions is presented. With this innovative experimental set-up, it is possible to obtain real-time emissions of the combustion products without the need of dilution or sample collection. Key pollutants such as CO, CO2, H2CO, CH4, NO, N2O, NH3, SO2, CH3OH, acetylene, ethylene, ethane and total hydrocarbons, most of which are not regulated nor measured by current emissions control programs, can be accurately monitored with a single instrument. An FTIR spectrometer is used for the analysis of a constant flow of sample gas from the tail-pipe into a stainless-steel cylindrical cell of constant volume.(1) The cell is heated to 185 °C to avoid condensation, the pressure is kept constant and a multi-pass optical arrangement(2)is used to transmit the modulated infrared beam several times to improve the sensitivity. The total flow from the exhaust used for calculating the emission can be continuously determined from the differential pressure measurements from a "Pitot" tube calibrated against a hot-wire devise. This simple methodology is proposed for performing state-of-the-art evaluations on the emission behavior of new technologies, reformulated fuels and emission control devices. The results presented here were performed on a dynamometer running FTP-75 and driving cycles typical for Mexico City.(3,4) References 1. Grutter M. "Multi-Gas Analysis using FTIR Spectroscopy over Mexico City." Atmosfera 16, 1-16 (2003). 2. White J.U. "Long optical paths of large aperture. J. Opt. Soc. Am., 32, 285-288 (1942). 3. Santiago Cruz L. and P.I. Rincón. "Instrumentation of the Emission Control Laboratory at the Engineering School of the National Autonomous University of Mexico." Instrumentation and Development 4, 19-24, (2000). 4. González Oropeza R. and A. Galván Zacarías. "Desarrollo de ciclos de manejo característicos de la Ciudad de México." Memorias del IX Congreso Anual, Soc. Mex. de Ing. Mec. 535-544 (2003).

Cold season emissions dominate the Arctic tundra methane budget

NASA Astrophysics Data System (ADS)

Zona, Donatella; Gioli, Beniamino; Commane, Róisín; Lindaas, Jakob; Wofsy, Steven C.; Miller, Charles E.; Dinardo, Steven J.; Dengel, Sigrid; Sweeney, Colm; Karion, Anna; Chang, Rachel Y.-W.; Henderson, John M.; Murphy, Patrick C.; Goodrich, Jordan P.; Moreaux, Virginie; Liljedahl, Anna; Watts, Jennifer D.; Kimball, John S.; Lipson, David A.; Oechel, Walter C.

2016-01-01

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y-1, ∼25% of global emissions from extratropical wetlands, or ∼6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.

Cold season emissions dominate the Arctic tundra methane budget.

PubMed

Zona, Donatella; Gioli, Beniamino; Commane, Róisín; Lindaas, Jakob; Wofsy, Steven C; Miller, Charles E; Dinardo, Steven J; Dengel, Sigrid; Sweeney, Colm; Karion, Anna; Chang, Rachel Y-W; Henderson, John M; Murphy, Patrick C; Goodrich, Jordan P; Moreaux, Virginie; Liljedahl, Anna; Watts, Jennifer D; Kimball, John S; Lipson, David A; Oechel, Walter C

2016-01-05

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥ 50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y(-1), ∼ 25% of global emissions from extratropical wetlands, or ∼ 6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.

Cold season emissions dominate the Arctic tundra methane budget

PubMed Central

Zona, Donatella; Gioli, Beniamino; Lindaas, Jakob; Wofsy, Steven C.; Miller, Charles E.; Dinardo, Steven J.; Dengel, Sigrid; Sweeney, Colm; Karion, Anna; Chang, Rachel Y.-W.; Henderson, John M.; Murphy, Patrick C.; Goodrich, Jordan P.; Moreaux, Virginie; Liljedahl, Anna; Watts, Jennifer D.; Kimball, John S.; Lipson, David A.; Oechel, Walter C.

2016-01-01

Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the “zero curtain” period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y−1, ∼25% of global emissions from extratropical wetlands, or ∼6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming. PMID:26699476

Cold season emissions dominate the Arctic tundra methane budget

DOE PAGES

Zona, Donatella; Gioli, Beniamino; Commane, Róisín; ...

2015-12-22

Arctic terrestrial ecosystems are major global sources of methane (CH 4); hence, it is important to understand the seasonal and climatic controls on CH 4 emissions from these systems. Here, we report year-round CH 4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥ 50% of the annual CH 4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the “zero curtain” period, when subsurface soil temperatures are poised near 0more » °C. The zero curtain may persist longer than the growing season, and CH 4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH 4 derived from aircraft data demonstrate the large spatial extent of late season CH 4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH 4 y –1, ~25% of global emissions from extratropical wetlands, or ~6% of total global wetland methane emissions. Here, the dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH 4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.« less

N2O, NO, N2 and CO2 emissions from tropical savanna and grassland of northern Australia: an incubation experiment with intact soil cores

NASA Astrophysics Data System (ADS)

Werner, C.; Reiser, K.; Dannenmann, M.; Hutley, L. B.; Jacobeit, J.; Butterbach-Bahl, K.

2014-11-01

Strong seasonal variability of hygric and thermal soil conditions are a defining environmental feature in northern Australia. However, how such changes affect the soil-atmosphere exchange of nitrous oxide (N2O), nitric oxide (NO) and dinitrogen (N2) is still not well explored. By incubating intact soil cores from four sites (three savanna, one pasture) under controlled soil temperatures (ST) and soil moisture (SM) we investigated the release of the trace gas fluxes of N2O, NO and carbon dioxide (CO2). Furthermore, the release of N2 due to denitrification was measured using the helium gas flow soil core technique. Under dry pre-incubation conditions NO and N2O emissions were very low (<7.0 ± 5.0 μg NO-N m-2 h-1; <0.0 ± 1.4 μg N2O-N m-2 h-1) or in the case of N2O, even a net soil uptake was observed. Substantial NO (max: 306.5 μg N m-2 h-1) and relatively small N2O pulse emissions (max: 5.8 ± 5.0 μg N m-2 h-1) were recorded following soil wetting, but these pulses were short lived, lasting only up to 3 days. The total atmospheric loss of nitrogen was generally dominated by N2 emissions (82.4-99.3% of total N lost), although NO emissions contributed almost 43.2% to the total atmospheric nitrogen loss at 50% SM and 30 °C ST incubation settings (the contribution of N2 at these soil conditions was only 53.2%). N2O emissions were systematically higher for 3 of 12 sample locations, which indicates substantial spatial variability at site level, but on average soils acted as weak N2O sources or even sinks. By using a conservative upscale approach we estimate total annual emissions from savanna soils to average 0.12 kg N ha-1 yr-1 (N2O), 0.68 kg N ha-1 yr-1 (NO) and 6.65 kg N ha-1 yr-1 (N2). The analysis of long-term SM and ST records makes it clear that extreme soil saturation that can lead to high N2O and N2 emissions only occurs a few days per year and thus has little impact on the annual total. The potential contribution of nitrogen released due to pulse events compared to the total annual emissions was found to be of importance for NO emissions (contribution to total: 5-22%), but not for N2O emissions. Our results indicate that the total gaseous release of nitrogen from these soils is low and clearly dominated by loss in the form of inert nitrogen. Effects of seasonally varying soil temperature and moisture were detected, but were found to be low due to the small amounts of available nitrogen in the soils (total nitrogen <0.1%).

High resolution of anthropogenic atmospheric emissions of 12 heavy metals in the three biggest metropolitan areas, China

NASA Astrophysics Data System (ADS)

Tian, H.; Zhu, C.

2015-12-01

Atmospheric emissions of typical toxic heavy metals from anthropogenic sources have received worldwide concerns due to their adverse effects on human health and the ecosystem. An integrated inventory of anthropogenic emissions of twelve HMs (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu and Zn) in the three biggest metropolitan areas, including Beijing-Tianjin-Hebei (BTH) region, Yangtze River Delta (YRD) region and Pearl River Delta (PRD) region, are developed for 1980-2012 by combining with detailed activity data and inter-annual dynamic emission factors which are determined by S-shaped curves on account of technology progress, economic development, and emission control. The results indicate total emissions of twelve HMs in the three metropolitan regions have increased from 5448.8 tons in 1980 to 19054.9 tons in 2012, with an annual average growth rate of about 4.0%. Due to significant difference in industrial structures and energy consumption compositions, remarkable distinctions can be observed with respect to source contributions of total HM emissions from above three metropolitan areas. Specifically, the ferrous metal smelting sector, coal combustion by industrial boilers and coal combustion by power plants are found to be the primary source of total HM emissions in the BTH region (about 34.2%), YRD region (about 28.2%) and PRD region (about 24.3%), respectively. Furthermore, we allocate the annual emissions of these heavy metals in 2012 at a high spatial resolution of 9 km × 9 km grid with ArcGIS methodology and surrogate indexes, such as regional population and gross domestic product (GDP). The peak of HM emissions are mainly distributed over the grid cells of Beijing, Tianjin, Tangshan, Shijiazhuang, Handan and Baoding in the BTH region; Shanghai, Suzhou, Wuxi, Nanjing, Hangzhou, Ningbo in the YRD region; Guangzhou, Shenzhen, Dongguan, Foshan in the PYD region, respectively. Additionally, monthly emission profiles are established in order to further identify the temporal emission characteristics of HMs. Key words: heavy metals (HMs), emission inventory, time-varying dynamic emission factor, temporal and spatial characteristics, Beijing-Tianjin-Hebei (BTH) region, Yangtze River Delta (YRD) region, Pearl River Delta (PRD) region, China

The Net Climate Impact of Coal-Fired Power Plant Emissions

NASA Technical Reports Server (NTRS)

Shindell, D.; Faluvegi, G.

2010-01-01

Coal-fired power plants influence climate via both the emission of long-lived carbon dioxide (CO2) and short-lived ozone and aerosol precursors. Using a climate model, we perform the first study of the spatial and temporal pattern of radiative forcing specifically for coal plant emissions. Without substantial pollution controls, we find that near-term net global mean climate forcing is negative due to the well-known aerosol masking of the effects of CO2. Imposition of pollution controls on sulfur dioxide and nitrogen oxides leads to a rapid realization of the full positive forcing from CO2, however. Long-term global mean forcing from stable (constant) emissions is positive regardless of pollution controls. Emissions from coal-fired power plants until 1970, including roughly 1/3 of total anthropogenic CO2 emissions, likely contributed little net global mean climate forcing during that period though they may have induce weak Northern Hemisphere mid-latitude (NHml) cooling. After that time many areas imposed pollution controls or switched to low sulfur coal. Hence forcing due to emissions from 1970 to 2000 and CO2 emitted previously was strongly positive and contributed to rapid global and especially NHml warming. Most recently, new construction in China and India has increased rapidly with minimal application of pollution controls. Continuation of this trend would add negative near-term global mean climate forcing but severely degrade air quality. Conversely, following the Western and Japanese pattern of imposing air quality pollution controls at a later time could accelerate future warming rates, especially at NHmls. More broadly, our results indicate that due to spatial and temporal inhomogeneities in forcing, climate impacts of multi-pollutant emissions can vary strongly from region to region and can include substantial effects on maximum rate-of-change, neither of which are captured by commonly used global metrics. The method we introduce here to estimate regional temperature responses may provide additional insight.

Enhanced winter soil frost reduces methane emission during the subsequent growing season in a boreal peatland.

PubMed

Zhao, Junbin; Peichl, Matthias; Nilsson, Mats B

2016-02-01

Winter climate change may result in reduced snow cover and could, consequently, alter the soil frost regime and biogeochemical processes underlying the exchange of methane (CH4 ) in boreal peatlands. In this study, we investigated the short-term (1-3 years) vs. long-term (11 years) effects of intensified winter soil frost (induced by experimental snow exclusion) on CH4 exchange during the following growing season in a boreal peatland. In the first 3 years (2004-2006), lower CH4 emissions in the treatment plots relative to the control coincided with delayed soil temperature increase in the treatment plots at the beginning of the growing season (May). After 11 treatment years (in 2014), CH4 emissions were lower in the treatment plots relative to the control over the entire growing season, resulting in a reduction in total growing season CH4 emission by 27%. From May to July 2014, reduced sedge leaf area coincided with lower CH4 emissions in the treatment plots compared to the control. From July to August, lower dissolved organic carbon concentrations in the pore water of the treatment plots explained 72% of the differences in CH4 emission between control and treatment. In addition, greater Sphagnum moss growth in the treatment plots resulted in a larger distance between the moss surface and the water table (i.e., increasing the oxic layer) which may have enhanced the CH4 oxidation potential in the treatment plots relative to the control in 2014. The differences in vegetation might also explain the lower temperature sensitivity of CH4 emission observed in the treatment plots relative to the control. Overall, this study suggests that greater soil frost, associated with future winter climate change, might substantially reduce the growing season CH4 emission in boreal peatlands through altering vegetation dynamics and subsequently causing vegetation-mediated effects on CH4 exchange. © 2015 John Wiley & Sons Ltd.

The net climate impact of coal-fired power plant emissions

NASA Astrophysics Data System (ADS)

Shindell, D.; Faluvegi, G.

2010-04-01

Coal-fired power plants influence climate via both the emission of long-lived carbon dioxide (CO2) and short-lived ozone and aerosol precursors. Using a climate model, we perform the first study of the spatial and temporal pattern of radiative forcing specifically for coal plant emissions. Without substantial pollution controls, we find that near-term net global mean climate forcing is negative due to the well-known aerosol masking of the effects of CO2. Imposition of pollution controls on sulfur dioxide and nitrogen oxides leads to a rapid realization of the full positive forcing from CO2, however. Long-term global mean forcing from stable (constant) emissions is positive regardless of pollution controls. Emissions from coal-fired power plants until ~1970, including roughly 1/3 of total anthropogenic CO2 emissions, likely contributed little net global mean climate forcing during that period though they may have induce weak Northern Hemisphere mid-latitude (NHml) cooling. After that time many areas imposed pollution controls or switched to low-sulfur coal. Hence forcing due to emissions from 1970 to 2000 and CO2 emitted previously was strongly positive and contributed to rapid global and especially NHml warming. Most recently, new construction in China and India has increased rapidly with minimal application of pollution controls. Continuation of this trend would add negative near-term global mean climate forcing but severely degrade air quality. Conversely, following the Western and Japanese pattern of imposing air quality pollution controls at a later time could accelerate future warming rates, especially at NHmls. More broadly, our results indicate that due to spatial and temporal inhomogenaities in forcing, climate impacts of multi-pollutant emissions can vary strongly from region to region and can include substantial effects on maximum rate-of-change, neither of which are captured by commonly used global metrics. The method we introduce here to estimate regional temperature responses may provide additional insight.

Effects of lignite application on ammonia and nitrous oxide emissions from cattle pens.

PubMed

Sun, Jianlei; Bai, Mei; Shen, Jianlin; Griffith, David W T; Denmead, Owen T; Hill, Julian; Lam, Shu Kee; Mosier, Arvin R; Chen, Deli

2016-09-15

Beef cattle feedlots are a major source of ammonia (NH3) emissions from livestock industries. We investigated the effects of lignite surface applications on NH3 and nitrous oxide (N2O) emissions from beef cattle feedlot pens. Two rates of lignite, 3 and 6kgm(-2), were tested in the treatment pen. No lignite was applied in the control pen. Twenty-four Black Angus steers were fed identical commercial rations in each pen. We measured NH3 and N2O concentrations continuously from 4th Sep to 13th Nov 2014 using Quantum Cascade Laser (QCL) NH3 analysers and a closed-path Fourier Transform Infrared Spectroscopy analyser (CP-FTIR) in conjunction with the integrated horizontal flux method to calculate NH3 and N2O fluxes. During the feeding period, 16 and 26% of the excreted nitrogen (N) (240gNhead(-1)day(-1)) was lost via NH3 volatilization from the control pen, while lignite application decreased NH3 volatilization to 12 and 18% of the excreted N, for Phase 1 and Phase 2, respectively. Compared to the control pen, lignite application decreased NH3 emissions by approximately 30%. Nitrous oxide emissions from the cattle pens were small, 0.10 and 0.14gN2O-Nhead(-1)day(-1) (<0.1% of excreted N) for the control pen, for Phase 1 and Phase 2, respectively. Lignite application increased direct N2O emissions by 40 and 57%, to 0.14 and 0.22gN2O-Nhead(-1)day(-1), for Phase 1 and Phase 2, respectively. The increase in N2O emissions resulting from lignite application was counteracted by the lower indirect N2O emission due to decreased NH3 volatilization. Using 1% as a default emission factor of deposited NH3 for indirect N2O emissions, the application of lignite decreased total N2O emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

Real-world operation conditions and on-road emissions of Beijing diesel buses measured by using portable emission measurement system and electric low-pressure impactor.

PubMed

Liu, Zhihua; Ge, Yunshan; Johnson, Kent C; Shah, Asad Naeem; Tan, Jianwei; Wang, Chu; Yu, Linxiao

2011-03-15

On-road measurement is an effective method to investigate real-world emissions generated from vehicles and estimate the difference between engine certification cycles and real-world operating conditions. This study presents the results of on-road measurements collected from urban buses which propelled by diesel engine in Beijing city. Two widely used Euro III emission level buses and two Euro IV emission level buses were chosen to perform on-road emission measurements using portable emission measurement system (PEMS) for gaseous pollutant and Electric Low Pressure Impactor (ELPI) for particulate matter (PM) number emissions. The results indicate that considerable discrepancies of engine operating conditions between real-world driving cycles and engine certification cycles have been observed. Under real-world operating conditions, carbon monoxide (CO) and hydrocarbon (HC) emissions can easily meet their respective regulations limits, while brake specification nitrogen oxide (bsNO(x)) emissions present a significant deviation from its corresponding limit. Compared with standard limits, the real-world bsNO(x) emission of the two Euro III emission level buses approximately increased by 60% and 120% respectively, and bsNO(x) of two Euro IV buses nearly twice standard limits because Selective Catalytic Reduction (SCR) system not active under low exhaust temperature. Particle mass were estimated via particle size distribution with the assumption that particle density and diameter is liner. The results demonstrate that nanometer size particulate matter make significant contribution to total particle number but play a minor role to total particle mass. It is suggested that specific certified cycle should be developed to regulate bus engines emissions on the test bench or use PEMS to control the bus emissions under real-world operating conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

Effects of low Earth orbit environment on the Long Duration Exposure Facility thermal control coatings

NASA Technical Reports Server (NTRS)

Sampair, Thomas R.; Berrios, William M.

1992-01-01

One of the benefits of the Long Duration Exposure Facility (LDEF) was the opportunity to study the before and after effects of low earth orbit space environment on the spacecraft thermal control coatings. Since the LDEF's thermal control was totally passive by design, the selection of the external surface absorptivity to emissivity ratio (alpha/epsilon) and the ability for the coating to retain the alpha/epsilon over time was an important consideration in the thermal design of the LDEF. The primary surface coating chosen for the LDEF structure was clear chromic anodized aluminum with an average design alpha/epsilon of 0.32/0.16. External surface absorptivity (alpha) and emissivity (epsilon) were measured on all intercostals, longerons, tray mounting flanges, thermal control panels, and a limited number of experiment surface coatings after the experiment trays were removed from the LDEF structure. All surface alpha/epsilon measurements were made using portable hand held infrared and solar spectrum reflectometers. The absorptivity measurements were taken with a Devices and Services SSR-ER version 5.0 solar spectra reflectometer which has a stated uncertainty of +/- 0.01, and all normal emissivity measurements were made using the Gier Dunkle DB-100 infrared reflectometer also with a stated uncertainty of +/- 0.01. Both instruments were calibrated in the laboratory by LaRC instrumentation personnel before being used in the field at KSC. A combined total of 733 measurements were taken on the anodized aluminum hardware which included the structure (intercostals, longerons, and center ring), earth and space end thermal control panels, and experiment tray mounting flanges. The facility thermal control coatings measured in this survey cover 33 percent of the total exposed LDEF surface area. To correlate low earth orbit environmental effects on the anodized coatings, measurements were taken in both exposed and unexposed surfaces and compared to quality assurance (QA) measurements taken on the new surfaces at the time of hardware fabrication in 1978. The results of investigation are presented.

Impacts of Aging Emission Control Systems on In-Use Heavy-Duty Diesel Truck Emission Rates

NASA Astrophysics Data System (ADS)

Preble, C.; Cados, T.; Harley, R.; Kirchstetter, T.

2017-12-01

Heavy-duty diesel trucks are a major source of nitrogen oxides (NOx) and black carbon (BC) in urban environments, contributing to persistent ozone and particulate matter air quality problems. Recently, diesel particle filter (DPF) and selective catalytic reduction (SCR) emission control systems have become standard equipment on new trucks. Particle filters can also be installed as a retrofit on older engines. Prior work has shown that exhaust filters and SCR systems effectively reduce BC and NOx emission rates by up to 90 and 80%, respectively (Preble et al., ES&T 2015). There is concern, however, that DPFs may promote the formation of ultrafine particles (UFP) and increase tailpipe emissions of nitrogen dioxide (NO2). Additionally, urea-based SCR systems for NOx control may form nitrous oxide (N2O), an important contributor to stratospheric ozone depletion. The effectiveness of these emission controls has been thoroughly evaluated in the laboratory, but the long-term durability of in-use systems and their impacts on co-emitted species have not been well characterized. To evaluate the in-use performance of DPF and SCR systems, pollutant emissions from thousands of diesel trucks were measured over several years at the Port of Oakland and the Caldecott Tunnel in the San Francisco Bay Area. Pollutants present in the exhaust plumes of individual trucks were measured at high time resolution (≥1 Hz) as trucks passed under a mobile lab stationed on an overpass. Fuel-based emission factors (g pollutant emitted per kg fuel burned) were calculated for individual trucks and linked via recorded license plates to vehicle attributes, including engine model year and installed emission control systems. Use of DPFs reduced the BC emission rate by up to 95% at both locations. SCR systems were more effective at reducing NOx emissions under the uphill, highway driving conditions at the Caldecott Tunnel. The emission rates of co-emitted species NO2, UFP, and N2O depended on driving mode. Some DPFs on trucks with 2007-2009 model year engines showed deterioration or failure in filter performance, leading to higher BC emission rates compared to the average for trucks without filters. Emission inventories may underestimate total on-road emissions from diesel trucks, especially if particle filter failure rates continue to increase over time.

The effect of diet manipulation on nitrous oxide and methane emissions from manure application to incubated grassland soils

NASA Astrophysics Data System (ADS)

Cardenas, L. M.; Chadwick, D.; Scholefield, D.; Fychan, R.; Marley, C. L.; Jones, R.; Bol, R.; Well, R.; Vallejo, A.

Changes to agricultural management, particularly of the nitrogen (N) input to farms, have great potential for mitigating emissions of N containing gases, especially the greenhouse gas nitrous oxide (N 2O). Manipulating diets fed to livestock is a potential method for controlling N excretion and emissions of greenhouse gases (GHG's) to the atmosphere. We selected three slurries derived from sheep that had been fed, either ensiled ryegrass ( Lolium hybridicum), lucerne ( Medicago sativa) or kale ( Brassica oleracea) and applied them to a grassland soil from the UK in a laboratory experiment using a special He/O 2 atmosphere incubation facility. The resulting fluxes of N 2O, CH 4 and N 2 were measured, with the largest total N fluxes generated by the ryegrass slurry treatment (14.23 ryegrass, 10.84 lucerne, 13.88 kale and 4.40 kg N ha -1 from the control). Methane was emitted only from the ryegrass slurry treatment. The isotopomer signatures for N 2O in the control and lucerne slurry treatments indicated that denitrification was the main process responsible for N 2O emissions.

Trends in onroad transportation energy and emissions.

PubMed

Frey, H Christopher

2018-06-01

Globally, 1.3 billion on-road vehicles consume 79 quadrillion BTU of energy, mostly gasoline and diesel fuels, emit 5.7 gigatonnes of CO 2 , and emit other pollutants to which approximately 200,000 annual premature deaths are attributed. Improved vehicle energy efficiency and emission controls have helped offset growth in vehicle activity. New technologies are diffusing into the vehicle fleet in response to fuel efficiency and emission standards. Empirical assessment of vehicle emissions is challenging because of myriad fuels and technologies, intervehicle variability, multiple emission processes, variability in operating conditions, and varying capabilities of measurement methods. Fuel economy and emissions regulations have been effective in reducing total emissions of key pollutants. Real-world fuel use and emissions are consistent with official values in the United States but not in Europe or countries that adopt European standards. Portable emission measurements systems, which uncovered a recent emissions cheating scandal, have a key role in regulatory programs to ensure conformity between "real driving emissions" and emission standards. The global vehicle fleet will experience tremendous growth, especially in Asia. Although existing data and modeling tools are useful, they are often based on convenience samples, small sample sizes, large variability, and unquantified uncertainty. Vehicles emit precursors to several important secondary pollutants, including ozone and secondary organic aerosols, which requires a multipollutant emissions and air quality management strategy. Gasoline and diesel are likely to persist as key energy sources to mid-century. Adoption of electric vehicles is not a panacea with regard to greenhouse gas emissions unless coupled with policies to change the power generation mix. Depending on how they are actually implemented and used, autonomous vehicles could lead to very large reductions or increases in energy consumption. Numerous other trends are addressed with regard to technology, emissions controls, vehicle operations, emission measurements, impacts on exposure, and impacts on public health. Without specific policies to the contrary, fossil fuels are likely to continue to be the major source of on-road vehicle energy consumption. Fuel economy and emission standards are generally effective in achieving reductions per unit of vehicle activity. However, the number of vehicles and miles traveled will increase. Total energy use and emissions depend on factors such as fuels, technologies, land use, demographics, economics, road design, vehicle operation, societal values, and others that affect demand for transportation, mode choice, energy use, and emissions. Thus, there are many opportunities to influence future trends in vehicle energy use and emissions.

40 CFR Table 5 to Subpart Eeee of... - Requirements for Performance Tests and Design Evaluations

Code of Federal Regulations, 2010 CFR

2010-07-01

... 1 through 10 a. A performance test to determine the organic HAP (or, upon approval, TOC) control... appendix A of 40 CFR part 63 for measuring form-aldehyde (A) Total organic HAP (or, upon approval, TOC), or... total organic HAP (or, upon approval, TOC) emissions are reduced by the required weight-percent or, as...

Effects of Plant Extracts on Microbial Population, Methane Emission and Ruminal Fermentation Characteristics in In vitro

PubMed Central

Kim, E. T.; Kim, C. -H.; Min, K. -S.; Lee, S. S.

2012-01-01

This study was conducted to evaluate effects of plant extracts on methanogenesis and rumen microbial diversity in in vitro. Plant extracts (Artemisia princeps var. Orientalis; Wormwood, Allium sativum for. Pekinense; Garlic, Allium cepa; Onion, Zingiber officinale; Ginger, Citrus unshiu; Mandarin orange, Lonicera japonica; Honeysuckle) were obtained from the Plant Extract Bank at Korea Research Institute of Bioscience and Biotechnology. The rumen fluid was collected before morning feeding from a fistulated Holstein cow fed timothy and commercial concentrate (TDN; 73.5%, crude protein; 19%, crude fat; 3%, crude fiber; 12%, crude ash; 10%, Ca; 0.8%, P; 1.2%) in the ratio of 3 to 2. The 30 ml of mixture, comprising McDougall buffer and rumen liquor in the ratio of 4 to 1, was dispensed anaerobically into serum bottles containing 0.3 g of timothy substrate and plant extracts (1% of total volume, respectively) filled with O2-free N2 gas and capped with a rubber stopper. The serum bottles were held in a shaking incubator at 39°C for 24 h. Total gas production in all plant extracts was higher (p<0.05) than that of the control, and total gas production of ginger extract was highest (p<0.05). The methane emission was highest (p<0.05) at control, but lowest (p<0.05) at garlic extract which was reduced to about 20% of methane emission (40.2 vs 32.5 ml/g DM). Other plant extracts also resulted in a decrease in methane emissions (wormwood; 8%, onion; 16%, ginger; 16.7%, mandarin orange; 12%, honeysuckle; 12.2%). Total VFAs concentration and pH were not influenced by the addition of plant extracts. Acetate to propionate ratios from garlic and ginger extracts addition samples were lower (p<0.05, 3.36 and 3.38 vs 3.53) than that of the control. Real-time PCR indicted that the ciliate-associated methanogen population in all added plant extracts decreased more than that of the control, while the fibrolytic bacteria population increased. In particular, the F. succinogens community in added wormwood, garlic, mandarin orange and honeysuckle extracts increased more than that of the others. The addition of onion extract increased R. albus diversity, while other extracts did not influence the R. albus community. The R. flavefaciens population in added wormwood and garlic extracts decreased, while other extracts increased its abundance compared to the control. In conclusion, the results indicated that the plant extracts used in the experiment could be promising feed additives to decrease methane gas emission from ruminant animals while improving ruminal fermentation. PMID:25049630

Effects of Plant Extracts on Microbial Population, Methane Emission and Ruminal Fermentation Characteristics in In vitro.

PubMed

Kim, E T; Kim, C-H; Min, K-S; Lee, S S

2012-06-01

This study was conducted to evaluate effects of plant extracts on methanogenesis and rumen microbial diversity in in vitro. Plant extracts (Artemisia princeps var. Orientalis; Wormwood, Allium sativum for. Pekinense; Garlic, Allium cepa; Onion, Zingiber officinale; Ginger, Citrus unshiu; Mandarin orange, Lonicera japonica; Honeysuckle) were obtained from the Plant Extract Bank at Korea Research Institute of Bioscience and Biotechnology. The rumen fluid was collected before morning feeding from a fistulated Holstein cow fed timothy and commercial concentrate (TDN; 73.5%, crude protein; 19%, crude fat; 3%, crude fiber; 12%, crude ash; 10%, Ca; 0.8%, P; 1.2%) in the ratio of 3 to 2. The 30 ml of mixture, comprising McDougall buffer and rumen liquor in the ratio of 4 to 1, was dispensed anaerobically into serum bottles containing 0.3 g of timothy substrate and plant extracts (1% of total volume, respectively) filled with O2-free N2 gas and capped with a rubber stopper. The serum bottles were held in a shaking incubator at 39°C for 24 h. Total gas production in all plant extracts was higher (p<0.05) than that of the control, and total gas production of ginger extract was highest (p<0.05). The methane emission was highest (p<0.05) at control, but lowest (p<0.05) at garlic extract which was reduced to about 20% of methane emission (40.2 vs 32.5 ml/g DM). Other plant extracts also resulted in a decrease in methane emissions (wormwood; 8%, onion; 16%, ginger; 16.7%, mandarin orange; 12%, honeysuckle; 12.2%). Total VFAs concentration and pH were not influenced by the addition of plant extracts. Acetate to propionate ratios from garlic and ginger extracts addition samples were lower (p<0.05, 3.36 and 3.38 vs 3.53) than that of the control. Real-time PCR indicted that the ciliate-associated methanogen population in all added plant extracts decreased more than that of the control, while the fibrolytic bacteria population increased. In particular, the F. succinogens community in added wormwood, garlic, mandarin orange and honeysuckle extracts increased more than that of the others. The addition of onion extract increased R. albus diversity, while other extracts did not influence the R. albus community. The R. flavefaciens population in added wormwood and garlic extracts decreased, while other extracts increased its abundance compared to the control. In conclusion, the results indicated that the plant extracts used in the experiment could be promising feed additives to decrease methane gas emission from ruminant animals while improving ruminal fermentation.

On-road, in-use gaseous emission measurements by remote sensing of school buses equipped with diesel oxidation catalysts and diesel particulate filters.

PubMed

Burgard, Daniel A; Provinsal, Melissa N

2009-12-01

A remote sensing device was used to obtain on-road and in-use gaseous emission measurements from three fleets of schools buses at two locations in Washington State. This paper reports each fleet's carbon monoxide (CO), hydrocarbon (HC), nitric oxide (NO), and nitrogen dioxide (NO2) mean data. The fleets represent current emission retrofit technologies, such as diesel particulate filters and diesel oxidation catalysts, and a control fleet. This study shows that CO and HC emissions decrease with the use of either retrofit technology when compared with control buses of the same initial emission standards. The CO and HC emission reductions are consistent with published U.S. Environmental Protection Agency verified values. The total oxides of nitrogen (NOx), NO, and the NO2/NOx ratio all increase with each retrofit technology when compared with control buses. As was expected, the diesel particulate filters emitted significantly higher levels of NO2 than the control fleet because of the intentional conversion of NO to NO2 by these systems. Most prior research suggests that NOx emissions are unaffected by the retrofits; however, these previous studies have not included measurements from retrofit devices on-road and after nearly 5 yr of use. Two 2006 model-year buses were also measured. These vehicles did not have retrofit devices but were built to more stringent new engine standards. Reductions in HCs and NOx were observed for these 2006 vehicles in comparison to other non-retrofit earlier model-year vehicles.

Trends in on-road vehicle emissions and ambient air quality in Atlanta, Georgia, USA, from the late 1990s through 2009.

PubMed

Vijayaraghavan, Krish; DenBleyker, Allison; Ma, Lan; Lindhjem, Chris; Yarwood, Greg

2014-07-01

On-road vehicle emissions of carbon monoxide (CO), nitrogen oxides (NO(x)), and volatile organic compounds (VOCs) during 1995-2009 in the Atlanta Metropolitan Statistical Area were estimated using the Motor Vehicle Emission Simulator (MOVES) model and data from the National Emissions Inventories and the State of Georgia. Statistically significant downward trends (computed using the nonparametric Theil-Sen method) in annual on-road CO, NO(x), and VOC emissions of 6.1%, 3.3%, and 6.0% per year, respectively, are noted during the 1995-2009 period despite an increase in total vehicle distance traveled. The CO and NO(x) emission trends are correlated with statistically significant downward trends in ambient air concentrations of CO and NO(x) in Atlanta ranging from 8.0% to 11.8% per year and from 5.8% to 8.7% per year, respectively, during similar time periods. Weather-adjusted summertime ozone concentrations in Atlanta exhibited a statistically significant declining trend of 2.3% per year during 2001-2009. Although this trend coexists with the declining trends in on-road NO(x), VOC, and CO emissions, identifying the cause of the downward trend in ozone is complicated by reductions in multiple precursors from different source sectors. Implications: Large reductions in on-road vehicle emissions of CO and NO(x) in Atlanta from the late 1990s to 2009, despite an increase in total vehicle distance traveled, contributed to a significant improvement in air quality through decreases in ambient air concentrations of CO and NO(x) during this time period. Emissions reductions in motor vehicles and other source sectors resulted in these improvements and the observed declining trend in ozone concentrations over the past decade. Although these historical trends cannot be extrapolated to the future because pollutant concentration contributions due to on-road vehicle emissions will likely become an increasingly smaller fraction of the atmospheric total, they provide an indication of the benefits of past control measures.

Effects of biochar and other amendments on the physical properties and greenhouse gas emissions of an artificially degraded soil.

PubMed

Mukherjee, A; Lal, R; Zimmerman, A R

2014-07-15

Short and long-term impacts of biochar on soil properties under field conditions are poorly understood. In addition, there is a lack of field reports of the impacts of biochar on soil physical properties, gaseous emissions and C stability, particularly in comparison with other amendments. Thus, three amendments - biochar produced from oak at 650°C, humic acid (HA) and water treatment residual - (WTR) were added to a scalped silty-loam soil @ 0.5% (w/w) in triplicated plots under soybean. Over the 4-month active growing season, all amendments significantly increased soil pH, but the effect of biochar was the greatest. Biochar significantly increased soil-C by 7%, increased sub-nanopore surface area by 15% and reduced soil bulk density by 13% compared to control. However, only WTR amendment significantly increased soil nanopore surface area by 23% relative to the control. While total cumulative CH4 and CO2 emissions were not significantly affected by any amendment, cumulative N2O emission was significantly decreased in the biochar-amended soil (by 92%) compared to control over the growing period. Considering both the total gas emissions and the C removed from the atmosphere as crop growth and C added to the soil, WTR and HA resulted in net soil C losses and biochar as a soil C gain. However, all amendments reduced the global warming potential (GWP) of the soil and biochar addition even produced a net negative GWP effect. The short observation period, low application rate and high intra-treatment variation resulted in fewer significant effects of the amendments on the physicochemical properties of the soils than one might expect indicating further possible experimentation altering these variables. However, there was clear evidence of amendment-soil interaction processes affecting both soil properties and gaseous emissions, particularly for biochar, that might lead to greater changes with additional field emplacement time. Copyright © 2014 Elsevier B.V. All rights reserved.

Emissions of mercury from the power sector in Poland

NASA Astrophysics Data System (ADS)

Zyśk, J.; Wyrwa, A.; Pluta, M.

2011-01-01

Poland belongs to the European Union countries with the highest mercury emissions. This is mainly related to coal combustion. This paper presents estimates of mercury emissions from power sector in Poland. In this work, the bottom-up approach was applied and over 160 emission point sources were analysed. For each, the characteristics of the whole technological chain starting from fuel quality, boiler type as well as emission controls were taken into account. Our results show that emissions of mercury from brown coal power plants in 2005 were nearly four times greater than those of hard coal power plants. These estimates differ significantly from national statistics and some possible reasons are discussed. For the first time total mercury emissions from the Polish power sector were differentiated into its main atmospheric forms: gaseous elemental (GEM), reactive gaseous (RGM) and particulate-bound mercury. Information on emission source location and the likely vertical distribution of mercury emissions, which can be used in modelling of atmospheric dispersion of mercury is also provided.

Application rate affects the degradation rate and hence emissions of chloropicrin in soil.

PubMed

Ashworth, Daniel J; Yates, Scott R; Stanghellini, Mike; van Wesenbeeck, Ian J

2018-05-01

Increasingly stringent regulations to control soil-air emissions of soil fumigants has led to much research effort aimed at reducing emission potential. Using laboratory soil columns, we aimed to investigate the relationship between chloropicrin (CP) application rate and its emissions from soil across a wide range of CP applications (equivalent to 56-392kgha -1 ). In contrast to the known behavior of other fumigants, total emission percentages were strongly and positively related to application rate (i.e., initial mass), ranging from 4 to 34% across the application rate range. When combined, data from a previous study and the present study showed good overall comparability in terms of CP application rate vs. emission percentage, yielding a second-order polynomial relationship with an R 2 value of 0.93 (n=12). The study revealed that mass losses of CP were strongly disproportional to application rate, also showing a polynomial relationship. Based on degradation studies, we consider that a shorter half-life (faster degradation) at lower application rates limited the amount of CP available for emission. The non-linear relationship between CP application rate and CP emissions (both as % of that applied and as total mass) suggests that low application rates likely lead to disproportionally low emission losses compared with higher application rates; such a relationship could be taken into account when assessing/mitigating risk, e.g., in the setting of buffer zone distances. Copyright © 2017 Elsevier B.V. All rights reserved.

Emission projections for the U.S. Environmental Protection Agency Section 812 second prospective Clean Air Act cost/benefit analysis.

PubMed

Wilson, James H; Mullen, Maureen A; Bollman, Andrew D; Thesing, Kirstin B; Salhotra, Manish; Divita, Frank; Neumann, James E; Price, Jason C; DeMocker, James

2008-05-01

Section 812 of the Clean Air Act Amendments (CAAA) of 1990 requires the U.S. Environmental Protection Agency (EPA) to perform periodic, comprehensive analyses of the total costs and total benefits of programs implemented pursuant to the CAAA. The first prospective analysis was completed in 1999. The second prospective analysis was initiated during 2005. The first step in the second prospective analysis was the development of base and projection year emission estimates that will be used to generate benefit estimates of CAAA programs. This paper describes the analysis, methods, and results of the recently completed emission projections. There are several unique features of this analysis. One is the use of consistent economic assumptions from the Department of Energy's Annual Energy Outlook 2005 (AEO 2005) projections as the basis for estimating 2010 and 2020 emissions for all sectors. Another is the analysis of the different emissions paths for both with and without CAAA scenarios. Other features of this analysis include being the first EPA analysis that uses the 2002 National Emission Inventory files as the basis for making 48-state emission projections, incorporating control factor files from the Regional Planning Organizations (RPOs) that had completed emission projections at the time the analysis was performed, and modeling the emission benefits of the expected adoption of measures to meet the 8-hr ozone National Ambient Air Quality Standards (NAAQS), the Clean Air Visibility Rule, and the PM2.5 NAAQS. This analysis shows that the 1990 CAAA have produced significant reductions in criteria pollutant emissions since 1990 and that these emission reductions are expected to continue through 2020. CAAA provisions have reduced volatile organic compound (VOC) emissions by approximately 7 million t/yr by 2000, and are estimated to produce associated VOC emission reductions of 16.7 million t by 2020. Total oxides of nitrogen (NO(x)) emission reductions attributable to the CAAA are 5, 12, and 17 million t in 2000, 2010, and 2020, respectively. Sulfur dioxide (SO2) emission benefits during the study period are dominated by electricity-generating unit (EGU) SO2 emission reductions. These EGU emission benefits go from 7.5 million t reduced in 2000 to 15 million t reduced in 2020.

Performance of a Retrofitted Multicyclone for PM2.5 Emission Control

NASA Astrophysics Data System (ADS)

Dewika, M.; Rashid, M.; Ammar, M. R.

2018-03-01

This paper presents on the performance of a retrofitted multicyclone system, which aims to increase the collection efficiency of PM2.5 (i.e. particulate size fraction ≤ 2.5 μm) emission. The multicyclone was retrofitted by extracting 15% and 20% of the total volumetric air flow rate at the dust hopper of the unit using an additional Induced Draft Fan. The total collection efficiency with and without the extraction was measured at various air volumetric flow rates and particulate mass inlet concentration. The results showed that there was a reduction of 12% to 54% depending on the inlet concentration of PM2.5 emission in the stack with compared to without extraction increasing the collection efficiency of the retrofitted multicyclone. The finding suggests that a simple technique of applying gas extraction at the dust hopper of a multicyclone as reported in this study able to increase the overall performance in fine particulate collection.

A High-Speed Continuous Recording High Flow Gas Sampler for Measuring Methane Emissions from Pneumatic Devices at Oil and Natural Gas Production Facilities

NASA Astrophysics Data System (ADS)

Ferrara, T.; Howard, T. M.

2016-12-01

Studies attempting to reconcile facility level emission estimates of sources at oil and gas facilities with basin wide methane flux measurements have had limited success. Pneumatic devices are commonly used at oil and gas production facilities for process control or liquid pumping. These devices are powered by pressurized natural gas from the well, so they are known methane sources at these sites. Pneumatic devices are estimated to contribute 14% to 25% of the total greenhouse gas emissions (GHG) from production facilities. Measurements of pneumatic devices have shown that malfunctioning or poorly maintained control systems may be emitting significantly more methane than currently estimated. Emission inventories for these facilities use emission factors from EPA that are based on pneumatic device measurements made in the early 1990's. Recent studies of methane emissions from production facilities have attempted to measure emissions from pneumatic devices by several different methods. These methods have had limitations including alteration of the system being measured, the inability to distinguish between leaks and venting during normal operation, or insufficient response time to account of the time based emission events. We have developed a high speed recording high flow sampler that is capable of measuring the transient emissions from pneumatic devices. This sampler is based on the well-established high flow measurement technique used in oil and gas for quantifying component leak rates. In this paper we present the results of extensive laboratory controlled release testing. Additionally, test data from several field studies where this sampler has been used to measure pneumatic device emissions will be presented.

Estimation of mercury emission from different sources to atmosphere in Chongqing, China.

PubMed

Wang, Dingyong; He, Lei; Wei, Shiqiang; Feng, Xinbin

2006-08-01

This investigation presents a first assessment of the contribution to the regional mercury budget from anthropogenic and natural sources in Chongqing, an important industrial region in southwest China. The emissions of mercury to atmosphere from anthropogenic sources in the region were estimated through indirect approaches, i.e. using commonly acceptable emission factors method, which based on annual process throughputs or consumption for these sources. The natural mercury emissions were estimated from selected natural sources by the dynamic flux chamber technique. The results indicated that the anthropogenic mercury emissions totaled approximately 8.85 tons (t), more than 50% of this total originated in coal combustion and 23.7% of this total emission in the industrial process (include cement production, metal smelting and chemical industry). The natural emissions represented approximately 17% of total emissions (1.78 t yr(-1)). The total mercury emission to atmosphere in Chongqing in 2001 was 10.63 t.

Urban air chemistry and diesel vehicles emissions: Quantifying small and big hydrocarbons by CIMS to improve emission inventories

NASA Astrophysics Data System (ADS)

Jobson, B. T.; Derstroff, B.; Edtbauer, A.; VanderSchelden, G. S.; Williams, J.

2017-10-01

Emissions from vehicles are a major source of volatile organic compounds (VOCs) in urban environments. Photochemical oxidation of VOCs emitted from vehicle exhaust contributes to O3 and PM2.5 formation, harmful pollutants that major urban areas struggle to control. How will a shift to a diesel engine fleet impact urban air chemistry? Diesel vehicles are a growing fraction of the passenger vehicle fleet in Europe as a result of a deliberate policy to reduce energy consumption and CO2 emissions from the transportation sector (Sullivan et al., 2004). In countries such as France the diesel passenger fleet was already ∼50% of the total in 2009, up from 20% in 1995. Dunmore et al. (2015) have recently inferred that in London, HO radical loss rates to organic compounds is dominated by diesel engine emissions. In the US, increasingly more stringent vehicles emission standards and requirement for improved energy efficiency means spark ignition passenger vehicle emissions have declined significantly over the last 20 years, resulting in the urban diesel fleet traffic (freight trucks) having a growing importance as a source of vehicle pollution (McDonald et al., 2013). The recent scandal involving a major car manufacturer rigging emission controls for diesel passenger cars is a reminder that real world emissions of VOCs from diesel engines are not well understood nor thoroughly accounted for in air quality modeling.

Kyoto-Related Fossil-Fuel CO2 Emission Totals (1990 - 2009) (Version 2012) (Updated 01/16/2013)

DOE Data Explorer

Marland, Greg [Appalachian State University, Boone, NC (USA); Boden, Thomas A. [Carbon Dioxide Information Analysis Center (CDIAC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN

2013-01-16

This table shows the total of CO2 emissions from fossil-fuel use and cement manufacture for those countries listed in Annex B of the Kyoto Protocol and for those countries not listed in Annex B. In keeping with the convention of the IPCC methodology for calculating national greenhouse gas emissions, emissions from international bunker fuels (fuels used in international commerce) are not included in the country totals but are shown separately under the country group in which final fuel loading occurred. Note, that the list of countries in Annex B of the Kyoto Protocol differs from the list of countries in Annex I of the Framework Convention on Climate Change by the addition of Croatia, Liechtenstein, Monaco, and Slovenia and the removal of Belarus and Turkey. We have estimated emissions for 1990 and 1991 from the republics that were formerly part of the USSR and of Yugoslavia by taking total emissions from the USSR (and Yugoslavia) for 1990 and 1991 and distributing them among the new republics in the same ratio as emissions from those republics in 1992. Because of minor differences in the method of estimating the global total of emissions and the national totals of emissions, the sum of emissions from all countries produces a number that is less than the global total by about 2%. Consequently we have inflated the sum of emissions from all Annex B countries and the sum of emissions from all non-Annex B countries by about 2% (the value differs from year to year) so that the sum of the two values plus emissions from bunker fuels is equal to our best estimate of the global total of emissions.

Variability of particle number emissions from diesel and hybrid diesel-electric buses in real driving conditions.

PubMed

Sonntag, Darrell B; Gao, H Oliver; Holmén, Britt A

2008-08-01

A linear mixed model was developed to quantify the variability of particle number emissions from transit buses tested in real-world driving conditions. Two conventional diesel buses and two hybrid diesel-electric buses were tested throughout 2004 under different aftertreatments, fuels, drivers, and bus routes. The mixed model controlled the confounding influence of factors inherent to on-board testing. Statistical tests showed that particle number emissions varied significantly according to the after treatment, bus route, driver, bus type, and daily temperature, with only minor variability attributable to differences between fuel types. The daily setup and operation of the sampling equipment (electrical low pressure impactor) and mini-dilution system contributed to 30-84% of the total random variability of particle measurements among tests with diesel oxidation catalysts. By controlling for the sampling day variability, the model better defined the differences in particle emissions among bus routes. In contrast, the low particle number emissions measured with diesel particle filters (decreased by over 99%) did not vary according to operating conditions or bus type but did vary substantially with ambient temperature.

Effects of Aftermarket Control Technologies on Gas and Particle Phase Oxidative Potential from Diesel Engine Emissions.

PubMed

Pavlovic, Jelica; Holder, Amara L; Yelverton, Tiffany L B

2015-09-01

Particulate matter (PM) originating from diesel combustion is a public health concern due to its association with adverse effects on respiratory and cardiovascular diseases and lung cancer. This study investigated emissions from three stationary diesel engines (gensets) and varying power output (230 kW, 400 kW, and 600 kW) at 50% and 90% load to determine concentrations of gaseous (GROS) and PM reactive oxygen species (PMROS). In addition, the influence of three modern emission control technologies on ROS emissions was evaluated: active and passive diesel particulate filters (A-DPF and P-DPF) and a diesel oxidation catalyst (DOC). PMROS made up 30-50% of the total ROS measured without aftermarket controls. All applied controls removed PMROS by more than 75% on average. However, the oxidative potential of PM downstream of these devices was not diminished at the same rate and particles surviving the A-PDF had an even higher oxidative potential on a per PM mass basis compared to the particles emitted by uncontrolled gensets. Further, the GROS as compared to PMROS emissions were not reduced with the same efficiency (<36%). GROS concentrations were highest with the DOC in use, indicating continued formation of GROS with this control. Correlation analyses showed that PMROS and to a lesser extent GROS have a good correlation with semivolatile organic carbon (OC1) subfraction. In addition, results suggest that chemical composition, rather than PM size, is responsible for differences in the PM oxidative potential.

Atmospheric emissions estimation of Hg, As, and Se from coal-fired power plants in China, 2007.

PubMed

Tian, Hezhong; Wang, Yan; Xue, Zhigang; Qu, Yiping; Chai, Fahe; Hao, Jiming

2011-07-15

Over half of coal in China is burned directly by power plants, becoming an important source of hazardous trace element emissions, such as mercury (Hg), arsenic (As), and selenium (Se), etc. Based on coal consumption by each power plant, emission factors classified by different boiler patterns and air pollution control devices configuration, atmospheric emissions of Hg, As, and Se from coal-fired power plants in China are evaluated. The national total emissions of Hg, As, and Se from coal-fired power plants in 2007 are calculated at 132 t, 550 t, and 787 t, respectively. Furthermore, according to the percentage of coal consumed by units equipped with different types of PM devices and FGD systems, speciation of mercury is estimated as follows: 80.48 t of Hg, 49.98 t of Hg(2+), and 1.89 t of Hg(P), representing 60.81%, 37.76%, and 1.43% of the totals, respectively. The emissions of Hg, As, and Se in China's eastern and central provinces are much higher than those in the west, except for provinces involved in the program of electricity transmission from west to east China, such as Sichuan, Guizhou, Yunnan, Shaanxi, etc. Copyright © 2011 Elsevier B.V. All rights reserved.

Diesel passenger car PM emissions: From Euro 1 to Euro 4 with particle filter

NASA Astrophysics Data System (ADS)

Tzamkiozis, Theodoros; Ntziachristos, Leonidas; Samaras, Zissis

2010-03-01

This paper examines the impact of the emission control and fuel technology development on the emissions of gaseous and, in particular, PM pollutants from diesel passenger cars. Three cars in five configurations in total were measured, and covered the range from Euro 1 to Euro 4 standards. The emission control ranged from no aftertreatment in the Euro 1 case, an oxidation catalyst in Euro 2, two oxidation catalysts and exhaust gas recirculation in Euro 3 and Euro 4, while a catalyzed diesel particle filter (DPF) fitted in the Euro 4 car led to a Euro 4 + DPF configuration. Both certification test and real-world driving cycles were employed. The results showed that CO and HC emissions were much lower than the emission standard over the hot-start real-world cycles. However, vehicle technologies from Euro 2 to Euro 4 exceeded the NOx and PM emission levels over at least one real-world cycle. The NOx emission level reached up to 3.6 times the certification level in case of the Euro 4 car. PM were up to 40% and 60% higher than certification level for the Euro 2 and Euro 3 cars, while the Euro 4 car emitted close or slightly below the certification level over the real-world driving cycles. PM mass reductions from Euro 1 to Euro 4 were associated with a relevant decrease in the total particle number, in particular over the certification test. This was not followed by a respective reduction in the solid particle number which remained rather constant between the four technologies at 0.86 × 10 14 km -1 (coefficient of variation 9%). As a result, the ratio of solid vs. total particle number ranged from ˜50% in Euro 1-100% in Euro 4. A significant reduction of more than three orders of magnitude in solid particle number is achieved with the introduction of the DPF. However, the potential for nucleation mode formation at high speed from the DPF car is an issue that needs to be considered in the over all assessment of its environmental benefit. Finally, comparison of the mobility and aerodynamic diameters of airborne particles led to fractal dimensions dropping from 2.60 (Euro 1) to 2.51 (Euro 4), denoting a more loose structure with improving technology.

Hydrocarbon emission fingerprints from contemporary vehicle/engine technologies with conventional and new fuels

NASA Astrophysics Data System (ADS)

Montero, Larisse; Duane, Matthew; Manfredi, Urbano; Astorga, Covadonga; Martini, Giorgio; Carriero, Massimo; Krasenbrink, Alois; Larsen, B. R.

2010-06-01

The present paper presents results from the analysis of 29 individual C 2-C 9 hydrocarbons (HCs) specified in the European Commission Ozone Directive. The 29 HCs are measured in exhaust from common, contemporary vehicle/engine/fuel technologies for which very little or no data is available in the literature. The obtained HC emission fingerprints are compared with fingerprints deriving from technologies that are being phased out in Europe. Based on the total of 138 emission tests, thirteen type-specific fingerprints are extracted (Mean ± SD percentage contributions from individual HCs to the total mass of the 29 HCs), essential for receptor modelling source apportionment. The different types represent exhaust from Euro3 and Euro4 light-duty (LD) diesel and petrol-vehicles, Euro3 heavy-duty (HD) diesel exhaust, and exhaust from 2-stroke preEuro, Euro1 and Euro2 mopeds. The fuels comprise liquefied petroleum gas, petrol/ethanol blends (0-85% ethanol), and mineral diesel in various blends (0-100%) with fatty acid methyl esters, rapeseed methyl esters palm oil methyl esters, soybean oil methyl or sunflower oil methyl esters. Type-specific tracer compounds (markers) are identified for the various vehicle/engine/fuel technologies. An important finding is an insignificant effect on the HC fingerprints of varying the test driving cycle, indicating that combining HC fingerprints from different emission studies for receptor modelling purposes would be a robust approach. The obtained results are discussed in the context of atmospheric ozone formation and health implications from emissions (mg km -1 for LD and mopeds and mg kW h -1 for HD, all normalised to fuel consumption: mg dm -3 fuel) of the harmful HCs, benzene and 1,3-butadiene. Another important finding is a strong linear correlation of the regulated "total" hydrocarbon emissions (tot-HC) with the ozone formation potential of the 29 HCs (ΣPO 3 = (1.66 ± 0.04) × tot-RH; r2 = 0.93). Tot-HC is routinely monitored in emission control laboratories, whereas C 2-C 9 are not. The revealed strong correlations broadens the usability of data from vehicle emission control laboratories and facilitates the comparison of the ozone formation potential of HCs in exhaust from of old and new vehicle/engine/fuel technologies.

Heterogeneity of biochar amendment to improve the carbon and nitrogen sequestration through reduce the greenhouse gases emissions during sewage sludge composting.

PubMed

Awasthi, Mukesh Kumar; Wang, Meijing; Chen, Hongyu; Wang, Quan; Zhao, Junchao; Ren, Xiuna; Li, Dong-Sheng; Awasthi, Sanjeev Kumar; Shen, Feng; Li, Ronghua; Zhang, Zengqiang

2017-01-01

This study was performed to investigate the effects of biochar as an amendment to a gaseous emissions and sewage sludge (SS) composting dynamics. Six dosage of biochar [low dosage of biochar (LDB) - 2%, 4% and 6%; and higher dosage of biochar (HDB) - 8%, 12% and 18%] were amended to a mixture of SS and wheat straw (4:1 ratio on dry weight basis) and compared to control or without additive. The HDB significantly reduced CH 4 , N 2 O and NH 3 emission by 92.85-95.34%, 95.14-97.30% and 58.03-65.17%, but not the CO 2 emission. Meanwhile, humification results indicated that humic and fulvic acid 35-42% and 24-28% higher in the HDB amended treatments than those in the LDB and control treatments. The HDB significantly decreased total nitrogen losses and greenhouse gas emission, while LDB had significantly (p<0.001) higher CH 4 and N 2 O emissions. Due to effective performance of HDB, the 12% biochar was recommended to be used in SS composting practice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of particulate oxidation catalyst on unregulated pollutant emission and toxicity characteristics from heavy-duty diesel engine.

PubMed

Feng, Xiangyu; Ge, Yunshan; Ma, Chaochen; Tan, Jianwei

2015-01-01

To evaluate the effects of particulate oxidation catalyst (POC) on unregulated pollutant emission and toxicity characteristics, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), soot, soluble organic fractions (SOF) and sulphate emissions emitted from a heavy-duty diesel engine retrofitted with a POC were investigated on a diesel bench. The particulate matter (PM) in the exhaust was collected by Teflon membrane, and the PAHs and VOCs were analysed by a gas chromatography/mass spectrometer (GC/MS). The results indicate that the POC exhibits good performance on the emission control of VOCs, PAHs and PM. The POC and the diesel particulate filters (DPF) both show a good performance on reducing the VOCs emission. Though the brake-specific emission (BSE) reductions of the total PAHs by the POC were lower than those by the DPF, the POC still removed almost more than 50% of the total PAHs emission. After the engine was retrofitted with the POC, the reductions of the PM mass, SOF and soot emissions were 45.2-89.0%, 7.8-97.7% and 41.7-93.3%, respectively. The sulphate emissions decreased at low and medium loads, whereas at high load, the results were contrary. The PAHs emissions were decreased by 32.4-69.1%, and the contributions of the PAH compounds were affected by the POC, as well as by load level. The benzo[a]pyrene equivalent (BaPeq) of PAHs emissions were reduced by 35.9-97.6% with the POC. The VOCs emissions were reduced by 21.8-94.1% with the POC, and the reduction was more evident under high load.

Ship emission inventory and its impact on the PM2.5 air pollution in Qingdao Port, North China

NASA Astrophysics Data System (ADS)

Chen, Dongsheng; Wang, Xiaotong; Nelson, Peter; Li, Yue; Zhao, Na; Zhao, Yuehua; Lang, Jianlei; Zhou, Ying; Guo, Xiurui

2017-10-01

In this study, a first high temporal-spatial ship emission inventory in Qingdao Port and its adjacent waters has been developed using a ;bottom-up; method based on Automatic Identification System (AIS) data. The total estimated ship emissions for SO2, NOX, PM10, PM2.5, HC and CO in 2014 are 3.32 × 104, 4.29 × 104, 4.54 × 103, 4.18 × 103, 1.85 × 103 and 3.66 × 103 tonnes, respectively. Emissions of SO2 and NOX from ships account for 9% and 13% of the anthropogenic totals in Qingdao, respectively. The main contributors to the ship emissions are containers, followed by fishing ships, oil tankers and bulk carriers. The inter-monthly ship emissions varied significantly due to two reasons: stopping of the fishing ship activities during the fishing moratorium and the reduction of freight volume around the Chinese New Year Festival. Emissions from transport vessels concentrated basically along the shipping routes, while fishing ships contributed to massive irregular spatial emissions in the sea. The impact of ship emissions on the ambient air quality was further investigated using the Weather Research and Forecasting with Chemistry (WRF/Chem) model. The results reveal that the contribution of ship emissions to the PM2.5 concentrations in Qingdao is the highest in summer (13.1%) and the lowest in winter (1.5%). The impact was more evident over densely populated urban areas, where the contributions from ship emissions could be over 20% in July due to their close range to the docks. These results indicated that the management and control of the ship emissions are highly demanded considering their remarkable influence on the air quality and potential negative effects on human health.

Measurements of methane emissions at natural gas production sites in the United States.

PubMed

Allen, David T; Torres, Vincent M; Thomas, James; Sullivan, David W; Harrison, Matthew; Hendler, Al; Herndon, Scott C; Kolb, Charles E; Fraser, Matthew P; Hill, A Daniel; Lamb, Brian K; Miskimins, Jennifer; Sawyer, Robert F; Seinfeld, John H

2013-10-29

Engineering estimates of methane emissions from natural gas production have led to varied projections of national emissions. This work reports direct measurements of methane emissions at 190 onshore natural gas sites in the United States (150 production sites, 27 well completion flowbacks, 9 well unloadings, and 4 workovers). For well completion flowbacks, which clear fractured wells of liquid to allow gas production, methane emissions ranged from 0.01 Mg to 17 Mg (mean = 1.7 Mg; 95% confidence bounds of 0.67-3.3 Mg), compared with an average of 81 Mg per event in the 2011 EPA national emission inventory from April 2013. Emission factors for pneumatic pumps and controllers as well as equipment leaks were both comparable to and higher than estimates in the national inventory. Overall, if emission factors from this work for completion flowbacks, equipment leaks, and pneumatic pumps and controllers are assumed to be representative of national populations and are used to estimate national emissions, total annual emissions from these source categories are calculated to be 957 Gg of methane (with sampling and measurement uncertainties estimated at ± 200 Gg). The estimate for comparable source categories in the EPA national inventory is ~1,200 Gg. Additional measurements of unloadings and workovers are needed to produce national emission estimates for these source categories. The 957 Gg in emissions for completion flowbacks, pneumatics, and equipment leaks, coupled with EPA national inventory estimates for other categories, leads to an estimated 2,300 Gg of methane emissions from natural gas production (0.42% of gross gas production).

Measurements of methane emissions at natural gas production sites in the United States

PubMed Central

Allen, David T.; Torres, Vincent M.; Thomas, James; Sullivan, David W.; Harrison, Matthew; Hendler, Al; Herndon, Scott C.; Kolb, Charles E.; Fraser, Matthew P.; Hill, A. Daniel; Lamb, Brian K.; Miskimins, Jennifer; Sawyer, Robert F.; Seinfeld, John H.

2013-01-01

Engineering estimates of methane emissions from natural gas production have led to varied projections of national emissions. This work reports direct measurements of methane emissions at 190 onshore natural gas sites in the United States (150 production sites, 27 well completion flowbacks, 9 well unloadings, and 4 workovers). For well completion flowbacks, which clear fractured wells of liquid to allow gas production, methane emissions ranged from 0.01 Mg to 17 Mg (mean = 1.7 Mg; 95% confidence bounds of 0.67–3.3 Mg), compared with an average of 81 Mg per event in the 2011 EPA national emission inventory from April 2013. Emission factors for pneumatic pumps and controllers as well as equipment leaks were both comparable to and higher than estimates in the national inventory. Overall, if emission factors from this work for completion flowbacks, equipment leaks, and pneumatic pumps and controllers are assumed to be representative of national populations and are used to estimate national emissions, total annual emissions from these source categories are calculated to be 957 Gg of methane (with sampling and measurement uncertainties estimated at ±200 Gg). The estimate for comparable source categories in the EPA national inventory is ∼1,200 Gg. Additional measurements of unloadings and workovers are needed to produce national emission estimates for these source categories. The 957 Gg in emissions for completion flowbacks, pneumatics, and equipment leaks, coupled with EPA national inventory estimates for other categories, leads to an estimated 2,300 Gg of methane emissions from natural gas production (0.42% of gross gas production). PMID:24043804

Anaerobic digestion of thermal pre-treated sludge at different solids concentrations--Computation of mass-energy balance and greenhouse gas emissions.

PubMed

Pilli, Sridhar; More, Tanaji; Yan, Song; Tyagi, Rajeshwar Dayal; Surampalli, Rao Y

2015-07-01

The effect of thermal pre-treatment on sludge anaerobic digestion (AD) efficiency was studied at different total solids (TS) concentrations (20.0, 30.0 and 40.0 g TS/L) and digestion times (0, 5, 10, 15, 20 and 30 days) for primary, secondary and mixed wastewater sludge. Moreover, sludge pre-treatment, AD and disposal processes were evaluated based on a mass-energy balance and corresponding greenhouse gas (GHG) emissions. Mass balance revealed that the least quantity of digestate was generated by thermal pre-treated secondary sludge at 30.0 g TS/L. The net energy (energy output-energy input) and energy ratio (energy output/energy input) for thermal pre-treated sludge was greater than control in all cases. The reduced GHG emissions of 73.8 × 10(-3) g CO2/g of total dry solids were observed for the thermal pre-treated secondary sludge at 30.0 g TS/L. Thermal pre-treatment of sludge is energetically beneficial and required less retention time compared to control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of timing of joint application of hydroquinone and dicyandiamide on nitrous oxide emission from irrigated lowland rice paddy field.

PubMed

Li, Xianglan; Zhang, Guangbin; Xu, Hua; Cai, Zucong; Yagi, Kazuyuki

2009-06-01

A field experiment was conducted to study the effect of timing of joint application of urease inhibitor hydroquinone (HQ) and nitrification inhibitor dicyandiamide (DCD) on N(2)O emission from irrigated lowland rice paddy field. Four treatments including Treatment CK (the control with urea alone), HQ/DCD-1 (application of HQ and DCD together with fertilizer before transplanting), HQ/DCD-2 (HQ and DCD with fertilizer at tillering stage) and HQ/DCD-3 (HQ and DCD with fertilizer at panicle initiation stage) were designed and implemented separately during rice growth period. Seasonal peaks of N(2)O flux occurred during midseason drainage and significant negative correlation between N(2)O flux and water layer depth was observed (r=-0.69 to -0.75, P<0.01). Mean N(2)O flux was the highest in the control with urea alone, while joint addition of HQ and DCD with urea lowered mean N(2)O flux considerably (P<0.05). Total N(2)O emission during rice growth season in Treatment CK, HQ/DCD-1, HQ/DCD-2 and HQ/DCD-3 was 3.90, 2.98, 1.73 and 3.23kgN(2)O-N ha(-1), respectively. Application of HQ and DCD together with basal fertilizer, tillering fertilizer and panicle initiation fertilizer decreased the total N(2)O emission by 24%, 56% and 17%, respectively, while increased grain yield by 10%, 18% and 6%, respectively. Effect of application of inhibitors on N(2)O emission during the continuous period from incorporation of HQ and DCD to rice harvest was also studied, where results indicating that the highest inhibiting efficiency of inhibitors on N(2)O emission was recorded when HQ and DCD applied with fertilizer at tillering stage.

Biogenic volatile organic compound emissions from senescent maize leaves and a comparison with other leaf developmental stages

NASA Astrophysics Data System (ADS)

Mozaffar, A.; Schoon, N.; Bachy, A.; Digrado, A.; Heinesch, B.; Aubinet, M.; Fauconnier, M.-L.; Delaplace, P.; du Jardin, P.; Amelynck, C.

2018-03-01

Plants are the major source of Biogenic Volatile Organic Compounds (BVOCs) which have a large influence on atmospheric chemistry and the climate system. Therefore, understanding of BVOC emissions from all abundant plant species at all developmental stages is very important. Nevertheless, investigations on BVOC emissions from even the most widespread agricultural crop species are rare and mainly confined to the healthy green leaves. Senescent leaves of grain crop species could be an important source of BVOCs as almost all the leaves senesce on the field before being harvested. For these reasons, BVOC emission measurements have been performed on maize (Zea mays L.), one of the most cultivated crop species in the world, at all the leaf developmental stages. The measurements were performed in controlled environmental conditions using dynamic enclosures and proton transfer reaction mass spectrometry (PTR-MS). The main compounds emitted by senescent maize leaves were methanol (31% of the total cumulative BVOC emission on a mass of compound basis) and acetic acid (30%), followed by acetaldehyde (11%), hexenals (9%) and m/z 59 compounds (acetone/propanal) (7%). Important differences were observed in the temporal emission profiles of the compounds, and both yellow leaves during chlorosis and dry brown leaves after chlorosis were identified as important senescence-related BVOC sources. Total cumulative BVOC emissions from senescent maize leaves were found to be among the highest for senescent Poaceae plant species. BVOC emission rates varied strongly among the different leaf developmental stages, and senescent leaves showed a larger diversity of emitted compounds than leaves at earlier stages. Methanol was the compound with the highest emissions for all the leaf developmental stages and the contribution from the young-growing, mature, and senescent stages to the total methanol emission by a typical maize leaf was 61, 13, and 26%, respectively. This study shows that BVOC emissions from senescent maize leaves cannot be neglected and further investigations in field conditions are recommended to further constrain the BVOC emissions from this important C4 crop species.

Sources of nitrogen deposition in Federal Class I areas in the US

NASA Astrophysics Data System (ADS)

Lee, H.-M.; Paulot, F.; Henze, D. K.; Travis, K.; Jacob, D. J.; Pardo, L. H.; Schichtel, B. A.

2016-01-01

It is desired to control excessive reactive nitrogen (Nr) deposition due to its detrimental impact on ecosystems. Using a three-dimensional atmospheric chemical transport model, GEOS-Chem, Nr deposition in the contiguous US and eight selected Class I areas (Voyageurs (VY), Smoky Mountain (SM), Shenandoah (SD), Big Bend (BB), Rocky Mountain (RM), Grand Teton (GT), Joshua Tree (JT), and Sequoia (SQ)) is investigated. First, modeled Nr deposition is compared with National Trends Network (NTN) and Clean Air Status and Trends Network (CASTNET) deposition values. The seasonality of measured species is generally well represented by the model (R2 > 0.6), except in JT. While modeled Nr is generally within the range of seasonal observations, large overestimates are present in sites such as SM and SD in the spring and summer (up to 0.6 kg N ha month-1), likely owing to model high-biases in surface HNO3. The contribution of non-measured species (mostly dry deposition of NH3) to total modeled Nr deposition ranges from 1 to 55 %. The spatial distribution of the origin of Nr deposited in each Class I area and the contributions of individual emission sectors are estimated using the GEOS-Chem adjoint model. We find the largest role of long-range transport for VY, where 50 % (90 %) of annual Nr deposition originates within 670 (1670) km of the park. In contrast, the Nr emission footprint is most localized for SQ, where 50 % (90 %) of the deposition originates from within 130 (370) km. Emissions from California contribute to the Nr deposition in remote areas in the western US (RM, GT). Mobile NOx and livestock NH3 are found to be the major sources of Nr deposition in all sites except BB, where contributions of NOx from lightning and soils to natural levels of Nr deposition are significant (˜ 40 %). The efficiency in terms of Nr deposition per kg emissions of NH3-N, NOx-N, and SO2-S are also estimated. Unique seasonal features are found in JT (opposing efficiency distributions for winter and summer), RM (large fluctuations in the range of effective regions), and SD (upwind NH3 emissions hindering Nr deposition). We also evaluate the contributions of emissions to the total area of Class I regions in critical load exceedance, and to the total magnitude of exceedance. We find that while it is effective to control emissions in the western US to reduce the area of regions in CL exceedance, it can be more effective to control emissions in the eastern US to reduce the magnitude of Nr deposition above the CL. Finally, uncertainty in the nitrogen deposition caused by uncertainty in the NH3 emission inventory is explored by comparing results based on two different NH3 inventories; noticeable differences in the emission inventories and thus sensitivities of up to a factor of four found in individual locations.

Sources of nitrogen deposition in Federal Class I areas in the US

NASA Astrophysics Data System (ADS)

Lee, H.-M.; Paulot, F.; Henze, D. K.; Travis, K.; Jacob, D. J.; Pardo, L. H.; Schichtel, B. A.

2015-08-01

It is desired to control excessive reactive nitrogen (Nr) deposition due to its detrimental impact on ecosystems. Using a 3-dimensional atmospheric chemical transport model, GEOS-Chem, Nr deposition in the contiguous US and eight selected Class I areas (Voyageurs (VY), Smoky Mountain (SM), Shenandoah (SD), Big Bend (BB), Rocky Mountain (RM), Grand Teton (GT), Joshua Tree (JT), and Sequoia (SQ)) is investigated. First, modeled Nr deposition is compared with National Trends Network (NTN) and Clean Air Status and Trends Network (CASTNET) measurements. The seasonality of measured species is generally well represented by the model (R2 > 0.6), except in JT. While modeled Nr is generally within the range of seasonal observations, large overestimates are present in sites such as SM and SD in the spring and summer (up to 0.6 kg N ha-1 month-1), likely owing to model high-biases in surface HNO3. The contribution of non-measured species (mostly dry deposition of NH3) to total modeled Nr deposition ranges from 1 to 55 %. The spatial distribution of the origin of Nr deposited in each Class I area and the contributions of individual emission sectors are estimated using the GEOS-Chem adjoint model. We find the largest role of long-range transport for VY, where 50 % (90 %) of annual Nr deposition originates within 670 (1670) km of the park. In contrast, the Nr emission footprint is most localized for SQ, where 50 % (90 %) of the deposition originates from within 130 (370) km. Emissions from California contribute to the Nr deposition in remote areas in the western US (RM, GT). Mobile NOx and livestock NH3 are found to be the major sources of Nr deposition in all sites except BB, where contributions of NOx from lightning and soils to natural levels of Nr deposition are significant (~ 40 %). The efficiency in terms of Nr deposition per kg emissions of NH3-N, NOx-N, and SO2-S are also estimated. Unique seasonal features are found in JT (opposing efficiency distributions for winter and summer), RM (large fluctuations in the range of effective regions), and SD (upwind NH3 emissions hindering Nr deposition). We also evaluate the contributions of emissions to the total area of Class I regions in critical load exceedance, and to the total magnitude of exceedance. We find that while it is effective to control emissions in the western US to reduce the area of regions in CL exceedance, it can be more effective to control emissions in the eastern US to reduce the magnitude of Nr deposition above the CL. Finally, uncertainty in the nitrogen deposition caused by uncertainty in the NH3 emission inventory is explored by comparing results based on two different NH3 inventories; noticeable differences in the emission inventories and thus sensitivities of up to factor of four found in individual locations.

Development of reduction scenarios for criteria air pollutants emission in Tehran Traffic Sector, Iran.

PubMed

Mohammadiha, Amir; Malakooti, Hossein; Esfahanian, Vahid

2018-05-01

Transport-related pollution as the main source of air pollution must be reduced in Tehran mega-city. The performance of various developed scenarios including BAU (Business As Usual) as baseline scenario, ECV (Elimination of carburetor equipped Vehicle), NEM (New Energy Motorcycles), HES (Higher Emission Standard), VCR (Vehicle Catalyst Replacement), FQE (Fuel Quality Enhancement), DPF (Diesel Particulate Filter) and TSA (Total Scenarios Aggregation) are evaluated by International Vehicle Model up to 2028. In the short term, the ECV, VCR, and FQE scenarios provided high performance in CO, VOCs and NOx emissions control. Also FQE has an excellent effect on SOx emission reduction (86%) and DPF on PM emissions (20%). In the mid-term, the VCR, ECV, and FQE scenarios were presented desirable mean emission reduction on CO, VOCs, and NOx. Moreover, NOx emission reduction of DPF scenario is the most common (14%). Again FQE scenario proves to have great effect on SOx emission reduction in mid-term (86%), DPF and HES scenarios on PM (DPF: 49% and HES: 17%). Finally for the long term, VCR, ECV, FQE, and NEM scenarios were shown good performance in emission control on CO, VOCs and NOx. For SOx only FQE has a good effect in all time periods (FQE: 86%) and DPF and HES scenarios have the best effect on PM emission reduction respectively (DPF: 51% and HES: 27%) compared with BAU scenario. However, DPF scenario increases 12% SOx emission in long-term (2028). It can be generally concluded that VCR and ECV scenarios would achieve a significant reduction on gaseous pollutants emission except for SOx in general and FQE scenarios have desirable performance for all gaseous pollutants in the short term and also for SOx and VOCs in long term. In addition, the DPF and HES would be desirable scenario for emission control on PM in Tehran Traffic Sector. Copyright © 2017 Elsevier B.V. All rights reserved.

Considerable contribution of the Montreal Protocol to declining greenhouse gas emissions from the United States

NASA Astrophysics Data System (ADS)

Hu, Lei; Montzka, Stephen A.; Lehman, Scott J.; Godwin, David S.; Miller, Benjamin R.; Andrews, Arlyn E.; Thoning, Kirk; Miller, John B.; Sweeney, Colm; Siso, Caroline; Elkins, James W.; Hall, Bradley D.; Mondeel, Debra J.; Nance, David; Nehrkorn, Thomas; Mountain, Marikate; Fischer, Marc L.; Biraud, Sébastien C.; Chen, Huilin; Tans, Pieter P.

2017-08-01

Ozone depleting substances (ODSs) controlled by the Montreal Protocol are potent greenhouse gases (GHGs), as are their substitutes, the hydrofluorocarbons (HFCs). Here we provide for the first time a comprehensive estimate of U.S. emissions of ODSs and HFCs based on precise measurements in discrete air samples from across North America and in the remote atmosphere. Derived emissions show spatial and seasonal variations qualitatively consistent with known uses and largely confirm U.S. Environmental Protection Agency (EPA) national emissions inventories for most gases. The measurement-based results further indicate a substantial decline of ODS emissions from 2008 to 2014, equivalent to 50% of the CO2-equivalent decline in combined emissions of CO2 and all other long-lived GHGs inventoried by the EPA for the same period. Total estimated CO2-equivalent emissions of HFCs were comparable to the sum of ODS emissions in 2014, but can be expected to decline in the future in response to recent policy measures.

Efficiency of an emissions payment system for nitrogen in sewage treatment plants - a case study.

PubMed

Malmaeus, J Mikael; Ek, Mats; Åmand, Linda; Roth, Susanna; Baresel, Christian; Olshammar, Mikael

2015-05-01

An emissions payment system for nitrogen in Swedish sewage treatment plants (STPs) was evaluated using a semi-empirical approach. The system was based on a tariff levied on each unit of nitrogen emitted by STPs, and profitable measures to reduce nitrogen emissions were identified for twenty municipal STPs. This was done through direct involvement with the plant personnel and the results were scaled up to cover all treatment plants larger than 2000 person equivalents in the Swedish tributary areas of the Kattegat and the Baltic Proper. The sum of costs and nitrogen reductions were compared with an assumed command-and-control regulation requiring all STPs to obtain 80% total nitrogen reduction in their effluents. Costs for the latter case were estimated using a database containing standard estimates for reduction costs by six specified measures. For both cases a total reduction target of 3000 tonnes of nitrogen was set. We did not find that the emissions payment system was more efficient in terms of total reduction costs, although some practical and administrative advantages could be identified. Our results emphasize the need to evaluate the performance of policy instruments on a case-by-case basis since the theoretical efficiency is not always reflected in practice. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of past, present and future health-cost externalities of air pollution in Europe and the contribution from international ship traffic using the EVA model system

NASA Astrophysics Data System (ADS)

Brandt, J.; Silver, J. D.; Christensen, J. H.; Andersen, M. S.; Bønløkke, J. H.; Sigsgaard, T.; Geels, C.; Gross, A.; Hansen, A. B.; Hansen, K. M.; Hedegaard, G. B.; Kaas, E.; Frohn, L. M.

2013-03-01

An integrated model system, EVA (Economic Valuation of Air pollution), based on the impact-pathway chain has been developed, to assess the health-related economic externalities of air pollution resulting from specific emission sources or sectors. The model system can be used to support policy-making with respect to emission control. In this study, we apply the EVA system to Europe, and perform a more detailed assessment of past, present, and future health-cost externalities of the total air pollution levels in Europe (including both natural and anthropogenic sources), represented by the years 2000, 2007, 2011, and 2020. We also assess the contribution to the health-related external costs from international ship traffic with special attention to the international ship traffic in the Baltic and North Seas, since special regulatory actions on sulphur emissions, called SECA (sulphur emission control area), have been introduced in these areas,. We conclude that despite efficient regulatory actions in Europe in recent decades, air pollution still constitutes a serious problem to human health, hence the related external costs are considerable. The total health-related external costs for the whole of Europe is estimated at 803 bn Euro yr-1 for the year 2000, decreasing to 537 bn Euro yr-1 in the year 2020. We estimate the total number of premature deaths in Europe in the year 2000 due to air pollution to be around 680 000 yr-1, decreasing to approximately 450 000 in the year 2020. The contribution from international ship traffic in the Northern Hemisphere was estimated to 7% of the total health-related external costs in Europe in the year 2000, increasing to 12% in the year 2020. In contrast, the contribution from international ship traffic in the Baltic Sea and the North Sea decreases 36% due to the regulatory efforts of reducing sulphur emissions from ship traffic in SECA. Introducing this regulatory instrument for all international ship traffic in the Northern Hemisphere, or at least in areas close to Europe, would have a significant positive impact on human health in Europe.

Assessment of past, present and future health-cost externalities of air pollution in Europe and the contribution from international ship traffic using the EVA model system

NASA Astrophysics Data System (ADS)

Brandt, J.; Silver, J. D.; Christensen, J. H.; Andersen, M. S.; Bønløkke, J. H.; Sigsgaard, T.; Geels, C.; Gross, A.; Hansen, A. B.; Hansen, K. M.; Hedegaard, G. B.; Kaas, E.; Frohn, L. M.

2013-08-01

An integrated model system, EVA (Economic Valuation of Air pollution), based on the impact-pathway chain has been developed to assess the health-related economic externalities of air pollution resulting from specific emission sources or sectors. The model system can be used to support policy-making with respect to emission control. In this study, we apply the EVA system to Europe, and perform a more detailed assessment of past, present, and future health-cost externalities of the total air pollution levels in Europe (including both natural and anthropogenic sources), represented by the years 2000, 2007, 2011, and 2020. We also assess the contribution to the health-related external costs from international ship traffic with special attention to the international ship traffic in the Baltic and North seas, since special regulatory actions on sulfur emissions, called SECA (sulfur emission control area), have been introduced in these areas. We conclude that, despite efficient regulatory actions in Europe in recent decades, air pollution still constitutes a serious problem for human health. Hence the related external costs are considerable. The total health-related external costs for the whole of Europe are estimated at 803 bn euros yr-1 for the year 2000, decreasing to 537 bn euros yr-1 in the year 2020. We estimate the total number of premature deaths in Europe in the year 2000 due to air pollution to be around 680 000 yr-1, decreasing to approximately 450 000 in the year 2020. The contribution from international ship traffic in the Northern Hemisphere was estimated to 7% of the total health-related external costs in Europe in the year 2000, increasing to 12% in the year 2020. In contrast, the contribution from international ship traffic in the Baltic Sea and the North Sea decreases 36% due to the regulatory efforts of reducing sulfur emissions from ship traffic in SECA. Introducing this regulatory instrument for all international ship traffic in the Northern Hemisphere, or at least in areas close to Europe, would have a significant positive impact on human health in Europe.

Assessment of Past, Present and Future Health-Cost Ex-ternalities of Air Pollution in Europe and the contribution from International Ship Traffic using the EVA Model System

NASA Astrophysics Data System (ADS)

Brandt, Jørgen; Silver, Jeremy D.; Christensen, Jesper H.; Andersen, Mikael S.; Bønløkke, Jakob H.; Sigsgaard, Torben; Geels, Camilla; Gross, Allan; Hansen, Ayoe B.; Hansen, Kaj M.; Hedegaard, Gitte B.; Kaas, Eigil; Frohn, Lise M.

2013-04-01

An integrated model system, EVA (Economic Valuation of Air pollution), based on the impact-pathway chain has been developed, to assess the health-related economic externalities of air pollution resulting from specific emission sources or sectors. The model system can be used to support policy-making with respect to emission control. In this study, we apply the EVA system to Europe, and perform a more detailed assessment of past, present, and future health-cost externalities of the total air pollution levels in Europe (including both natural and anthropogenic sources), represented by the years 2000, 2007, 2011, and 2020. We also assess the contribution to the health-related external costs from international ship traffic with special attention to the international ship traffic in the Baltic and North Seas, since special regulatory actions on sulphur emissions, called SECA (sulphur emission control area), have been intro-duced in these areas,. We conclude that despite efficient regulatory actions in Europe in recent decades, air pollution still constitutes a serious problem to human health, hence the related external costs are considerable. The total health-related external costs for the whole of Europe is estimated at 803 bn Euro/year for the year 2000, decreasing to 537 bn Euro/year in the year 2020. We estimate the total number of premature deaths in Europe in the year 2000 due to air pollution to be around 680,000/year, decreasing to approximately 450,000 in the year 2020. The contribution from international ship traffic in the Northern Hemisphere was estimated to 7% of the total health-related external costs in Europe in the year 2000, increasing to 12% in the year 2020. In contrast, the contribution from international ship traffic in the Baltic Sea and the North Sea decreases 36% due to the regulatory efforts of reducing sulphur emissions from ship traffic in SECA. Introducing this regulatory instrument for all international ship traffic in the Northern Hemisphere, or at least in areas close to Europe, would have a significant posi-tive impact on human health in Europe.

Motor vehicle nanoparticle emissions: Numerical simulations and comparisons with recent observations

NASA Astrophysics Data System (ADS)

Yu, F.

2002-05-01

Epidemiological studies have linked urban fine particles (FPs, diameter <= 2.5 um) to adverse health effects, and the EPA has proposed more stringent standards on the mass concentration of ambient FPs. Recently it has been pointed out that it is not sufficient to study only the mass of FPs. The main concern is that, while nanoparticles (NPs, diameter <= 50 nm) contribute a small fraction to the mass concentration of the ambient aerosol, they may contribute disproportionately to its toxicity. Furthermore, measurements indicate that pollution control measures to reduce FP mass emissions may paradoxically increase the number emissions of NPs. Future standards might be imposed on NP emissions and NP emissions from gasoline engines might also become a concern. Effective and least costly means of NP emission reduction must be based on a firm physical understanding of the formation mechanisms of NPs in the exhaust of motor vehicles. Measurements of NPs in motor engine exhaust have been made both in the laboratory and in the atmosphere under various conditions. In this study, we investigate the key processes and parameters controlling formation and evolution of NPs in vehicle exhaust through model simulations and comparisons with field measurements. The detailed aerosol dynamics are simulated with an advanced multi-type, multi-component, size-resolved microphysics model. The classical binary homogeneous nucleation of H2SO4-H2O fails to explain the observed NP properties. We find that chemiions generated in engine combustor may play an important role in the formation of NPs in vehicle exhaust. The predicted NP properties based on our ion-mediated nucleation of H2SO4-H2O consistently explain the measurements in terms of total NP concentrations, and their sensitivity to fuel sulfur contents, on-road vehicle speeds, soot concentrations, and dilution conditions. Our study indicates that total number of NPs formed is very sensitive to chemiion concentrations, and we propose a potentially effective technique to control vehicle NP emissions by imposing an electrical field (voltage < ~ 100 volts) on a section of the tailpipe to remove small ions.

Characterization of particle bound organic carbon from diesel vehicles equipped with advanced emission control technologies.

PubMed

Pakbin, Payam; Ning, Zhi; Schauer, James J; Sioutas, Constantinos

2009-07-01

A chassis dynamometer study was carried out by the University of Southern California in collaboration with the Air Resources Board (CARB) to investigate the physical, chemical, and toxicological characteristics of diesel emissions of particulate matter (PM) from heavy-duty vehicles. These heavy-duty diesel vehicles (HDDV) were equipped with advanced emission control technologies, designed to meet CARB retrofit regulations. A HDDV without any emission control devices was used as the baseline vehicle. Three advanced emission control technologies; continuously regenerating technology (CRT), zeolite- and vanadium-based selective catalytic reduction technologies (Z-SCRT and V-SCRT), were tested under transient (UDDS) (1) and cruise (80 kmph) driving cycles to simulate real-world driving conditions. This paper focuses on the characterization of the particle bound organic species from the vehicle exhaust. Physical and chemical properties of PM emissions have been reported by Biswas et al. Atmos. Environ. 2008, 42, 5622-5634) and Hu et al. (Atmos. Environ. 2008, submitted) Significant reductions in the emission factors (microg/mile) of particle bound organic compounds were observed in HDDV equipped with advanced emission control technologies. V-SCRT and Z-SCRT effectively reduced PAHs, hopanes and steranes, n-alkanes and acids by more than 99%, and often to levels below detection limits for both cruise and UDDS cycles. The CRT technology also showed similar reductions with SCRT for medium and high molecular weight PAHs, acids, but with slightly lower removal efficiencies for other organic compounds. Ratios of particle bound organics-to-OC mass (microg/g) from the baseline exhaust were compared with their respective ratios in diesel fuel and lubricating oil, which revealed that hopanes and steranes originate from lubricating oil, whereas PAHs can either form during the combustion process or originate from diesel fuel itself. With the introduction of emission control technologies, the particle bound organics-to-OC ratios (microg/g) decreased considerably for PAHs, while the reduction was insignificant for hopanes and steranes, implying that fuel and lubricating oil have substantially different contributions to the total OC emitted by vehicles operating with after-treatment control devices compared to the baseline vehicle since these control technologies had a much larger impact on PAH OC than hopanes and steranes OC.

[Influence of coke oven emissions on workers' blood pressure and electrocardiographic findings].

PubMed

Liang, J J; Yi, G L; Mao, G S; Wang, D M; Dai, X Y

2016-09-20

Objective: To investigate the influence of coke oven emissions on workers' blood pressure and electrocardiographic findings, and to provide a basis for the prevention and treatment of cardiovascular diseases. Methods: The concentration of coke oven emissions at the bottom, side, and top of coke ovens was determined in a coking plant. A total of 406 coke oven workers were enrolled as exposure group and 201 office staff members were enrolled as control group. Blood pressure and electrocardiographic findings were compared between the two groups, and the multivariate logistic regression analysis was performed to analyze the influencing factors for hypertension and abnormal electrocardiographic findings. Results: The concentration of coke oven emissions was the highest at the top of coke ovens, followed by the side and bottom of coke ovens, and there was a significant difference between the exposure group and the control group ( P <0.01). The exposure group had significantly higher detection rates of hypertension, abnormal electrocardiographic findings, and abnormal chest X-ray findings than the control group ( P <0.05). The logistic regression analysis showed that high concentration of coke oven emission and age were risk factors for hypertension and abnormal electrocardiographic findings ( P <0.05). The workers exposed to high-concentration coke oven emissions were more likely to experience hypertension and abnormal electrocardiographic findings than those exposed to low-concentration coke oven emissions ( OR =1.7 and 1.9). Conclusion: Besides lung injury, coke oven emissions also have adverse effects on the cardiovascular system. Therefore, more effective measures are needed to protect the health of coke oven workers.

Joint Optimization of Distribution Network Design and Two-Echelon Inventory Control with Stochastic Demand and CO2 Emission Tax Charges

PubMed Central

Li, Shuangyan; Li, Xialian; Zhang, Dezhi; Zhou, Lingyun

2017-01-01

This study develops an optimization model to integrate facility location and inventory control for a three-level distribution network consisting of a supplier, multiple distribution centers (DCs), and multiple retailers. The integrated model addressed in this study simultaneously determines three types of decisions: (1) facility location (optimal number, location, and size of DCs); (2) allocation (assignment of suppliers to located DCs and retailers to located DCs, and corresponding optimal transport mode choices); and (3) inventory control decisions on order quantities, reorder points, and amount of safety stock at each retailer and opened DC. A mixed-integer programming model is presented, which considers the carbon emission taxes, multiple transport modes, stochastic demand, and replenishment lead time. The goal is to minimize the total cost, which covers the fixed costs of logistics facilities, inventory, transportation, and CO2 emission tax charges. The aforementioned optimal model was solved using commercial software LINGO 11. A numerical example is provided to illustrate the applications of the proposed model. The findings show that carbon emission taxes can significantly affect the supply chain structure, inventory level, and carbon emission reduction levels. The delay rate directly affects the replenishment decision of a retailer. PMID:28103246

Atmospheric emission inventory of hazardous trace elements from China's coal-fired power plants--temporal trends and spatial variation characteristics.

PubMed

Tian, Hezhong; Liu, Kaiyun; Zhou, Junrui; Lu, Long; Hao, Jiming; Qiu, Peipei; Gao, Jiajia; Zhu, Chuanyong; Wang, Kun; Hua, Shenbing

2014-03-18

Coal-fired power plants are the important sources of anthropogenic atmospheric releases of various hazardous trace elements (HTE) because a large quantity of emissions can cause wide dispersion and possible long-distance transportation. To obtain the temporal trends and spatial variation characteristics of various HTE discharged from coal-fired power plants of China, a multiple-year comprehensive emission inventory of HTE including Hg, As, Se, Pb, Cd, Cr, Ni, and Sb has been established for the period 2000-2010. Thanks to the cobenefit removal effects of conventional particulate matter/sulfur dioxide/nitrogen oxides (PM/SO2/NOx) control devices, emissions of these 8 toxic elements have shown a gradual decline since the peak in 2006. The total emissions of Hg, As, Se, Pb, Cd, Cr, Ni, and Sb are substantial and are estimated at about 118.54, 335.45, 459.4, 705.45, 13.34, 505.03, 446.42, and 82.33 tons (t), respectively, in 2010. Shandong, Jiangsu, Shanxi, and Hebei always rank among the top ten provinces with the highest emissions. Further, future emissions for 2015 and 2020 are projected with scenario analysis. Advanced technologies and integrated management strategies to control HTE are in great need.

40 CFR 86.090-2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... chamber. Total hydrocarbon equivalent means the sum of the carbon mass emissions of non-oxygenated... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF... operating characteristics significantly similar to the theoretical Diesel combustion cycle. The non-use of a...

40 CFR 86.090-2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... chamber. Total hydrocarbon equivalent means the sum of the carbon mass emissions of non-oxygenated... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF... operating characteristics significantly similar to the theoretical Diesel combustion cycle. The non-use of a...

40 CFR 86.090-2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chamber. Total hydrocarbon equivalent means the sum of the carbon mass emissions of non-oxygenated... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF... operating characteristics significantly similar to the theoretical Diesel combustion cycle. The non-use of a...

3D-CFD analysis of diffusion and emission of VOCs in a FLEC cavity.

PubMed

Zhu, Q; Kato, S; Murakami, S; Ito, K

2007-06-01

This study is performed as a part of research that examines the emission and diffusion characteristics of volatile organic compounds (VOCs) from indoor building materials. In this paper, the flow field and the emission field of VOCs from the surface of building materials in a Field and Laboratory Emission Cell (FLEC) cavity are examined by 3D Computational Fluid Dynamics (CFD) analysis. The flow field within the FLEC cavity is laminar. With a total flow of 250 ml/min, the air velocity near the test material surface ranges from 0.1 to 4.5 cm/s. Three types of emission from building materials are studied here: (i) emission phenomena controlled by internal diffusion, (ii) emission phenomena controlled by external diffusion, and (iii) emission phenomena controlled by mixed diffusion (internal + external diffusion). In the case of internal diffusion material, with respect to the concentration distribution in the cavity, the local VOC emission rate becomes uniform and the FLEC works well. However, in the case of evaporation type (external diffusion) material, or mixed type materials (internal + external diffusion) when the resistance to transporting VOCs in the material is small, the FLEC is not suitable for emission testing because of the thin FLEC cavity. In this case, the mean emission rate is restricted to a small value, since the VOC concentration in the cavity rises to the same value as the surface concentration through molecular diffusion within the thin cavity, and the concentration gradient normal to the surface becomes small. The diffusion field and emission rate depend on the cavity concentration and on the Loading Factor. That is, when the testing material surface in the cavity is partially sealed to decrease the Loading Factor, the emission rate become higher with the decrease in the exposed area of the testing material. The flow field and diffusion field within the FLEC cavity are investigated by CFD method. After presenting a summary of the velocity distributed over the surface of test material and the emission properties of different type materials in FLEC, the paper pointed out that there is a bias in the airflow inside the FLEC cavity but do not influence the result of test emission rate, and the FLEC method is unsuitable for evaporation type materials in which the mass transfer of the surface controls the emission rate.

Study on emission characteristics of hybrid bus under driving cycles in typical Chinese city

NASA Astrophysics Data System (ADS)

Xie, Yongdong; Xu, Guangju

2017-09-01

In this study, hybrid city bus was taken as the research object, through the vehicle drum test, the vehicle emissions of hybrid bus, the transient emissions of gas pollutants, as well as the particle size and number distribution were surveyed. The results of the studies are listed as follows: First, compared to traditional fuel bus, hybrid bus could reduce about 44% of the NOx emissions, 33% of the total hydrocarbon emissions, and 51% of the particles emissions. Furthermore, the distribution of particles number concentration of test vehicle became high in middle and low in both sides. More specifically, the particle number concentration was mainly concentrated in the range from 0.021 to 0.755μm, the maximum was 0.2μm, and particle size of particulate matter (PM) less than 1.2μm accounted for 95% of the total number concentration. Particulate mass concentration was increased with increment of particle size, and the maximum of particulate mass (PM) concentration was 6.2μm. On average, whether traditional fuel bus or hybrid bus, the particle size of particulate matter(PM) less than 2.5μm accounted for more than 98% in the particles emission. It is found that the particles are more likely to deposit to the lung, respiratory bronchioles and alveoli, causing respiratory and lung diseases. Therefore, how to control the PM emissions of hybrid bus is the key factor of the study.

Assessment of Uinta Basin Oil and Natural Gas Well Pad ...

EPA Pesticide Factsheets

In the fall of 2016, a field study was conducted in the Uinta Basin Utah to improve information on oil and natural gas well pad pneumatic controllers (PCs) and emission measurement methods. A total of 80 PC systems at five oil sites (supporting six wells) and three gas sites (supporting 12 wells) were surveyed, and emissions data were produced using a combination of measurements and engineering emission estimates. Ninety-six percent of the PCs surveyed were the low actuation frequency intermittent vent type. The overall whole gas emission rate for the study was estimated at 0.37 scfh with the majority of emissions occurring from three continuous vent PCs (1.0 scfh average) and eleven (14%) malfunctioning intermittent vent PC systems (1.6 scfh average). Oil sites employed, on average 10.3 PC systems per well compared to 1.5 for gas sites. Oil and gas sites had group average PC emission rates of 0.28 scfh and 0.67 scfh, respectively, with this difference due in part to site selection procedures. The PC system types encountered, the engineering emissions estimate approach, and comparisons to measurements are described. Survey methods included identification of malfunctioning PC systems and emission measurements with augmented high volume sampling and installed mass flow meters, each providing a somewhat different picture of emissions that are elucidated through example cases. This paper reports on an oil and natural gas well pad pneumatic controller emissions stud

Evaluation of the effect of accounting method, IPCC v. LCA, on grass-based and confinement dairy systems' greenhouse gas emissions.

PubMed

O'Brien, D; Shalloo, L; Patton, J; Buckley, F; Grainger, C; Wallace, M

2012-09-01

Life cycle assessment (LCA) and the Intergovernmental Panel on Climate Change (IPCC) guideline methodology, which are the principal greenhouse gas (GHG) quantification methods, were evaluated in this study using a dairy farm GHG model. The model was applied to estimate GHG emissions from two contrasting dairy systems: a seasonal calving pasture-based dairy farm and a total confinement dairy system. Data used to quantify emissions from these systems originated from a research study carried out over a 1-year period in Ireland. The genetic merit of cows modelled was similar for both systems. Total mixed ration was fed in the Confinement system, whereas grazed grass was mainly fed in the grass-based system. GHG emissions from these systems were quantified per unit of product and area. The results of both methods showed that the dairy system that emitted the lowest GHG emissions per unit area did not necessarily emit the lowest GHG emissions possible for a given level of product. Consequently, a recommendation from this study is that GHG emissions be evaluated per unit of product given the growing affluent human population and increasing demand for dairy products. The IPCC and LCA methods ranked dairy systems' GHG emissions differently. For instance, the IPCC method quantified that the Confinement system reduced GHG emissions per unit of product by 8% compared with the grass-based system, but the LCA approach calculated that the Confinement system increased emissions by 16% when off-farm emissions associated with primary dairy production were included. Thus, GHG emissions should be quantified using approaches that quantify the total GHG emissions associated with the production system, so as to determine whether the dairy system was causing emissions displacement. The IPCC and LCA methods were also used in this study to simulate, through a dairy farm GHG model, what effect management changes within both production systems have on GHG emissions. The findings suggest that single changes have a small mitigating effect on GHG emissions (<5%), except for strategies used to control emissions from manure storage in the Confinement system (14% to 24%). However, when several management strategies were combined, GHG emissions per unit of product could be reduced significantly (15% to 30%). The LCA method was identified as the preferred approach to assess the effect of management changes on GHG emissions, but the analysis indicated that further standardisation of the approach is needed given the sensitivity of the approach to allocation decisions regarding milk and meat.

Modelling study of boundary-layer ozone over northern China - Part II: Responses to emission reductions during the Beijing Olympics

NASA Astrophysics Data System (ADS)

Tang, Guiqian; Zhu, Xiaowan; Xin, Jinyuan; Hu, Bo; Song, Tao; Sun, Yang; Wang, Lili; Wu, Fangkun; Sun, Jie; Cheng, Mengtian; Chao, Na; Li, Xin; Wang, Yuesi

2017-09-01

The implementation of emission reduction measures during the Olympics provided a valuable opportunity to study regional photochemical pollution over northern China. In this study, the fifth-generation Pennsylvania State University/National Centre for Atmospheric Research Mesoscale Model and Community Multiscale Air Quality model system was applied to conduct two sets of modelling analyses of the period from July 20 to September 20, 2008, to illustrate the influences of emission reduction measures on regional photochemical pollution over northern China during the Beijing Olympics. The results indicated that the implementation of emission control measures decreased the concentrations of ozone (O3) precursors, namely nitrogen oxide (NOx) and volatile organic compounds (VOCs), throughout the boundary layer. The concentrations of these compounds were reduced by 45% in the central urban area of Beijing at the ground level. Although the average O3 concentration in the central urban area increased by more than 8 ppbv, the total oxidant concentration decreased significantly by more than 5 ppbv. Greater O3 concentrations mainly occurred during periods with weak photochemical reactions. During periods of strong photochemical production, the O3 concentration decreased significantly due to a weakening vertical circulation between the lower and upper boundary layer. Consequently, the number of days when the O3 concentration exceeded 100 ppbv decreased by 25% in Beijing. The emission control measures altered the sensitivity of the regional O3 production. The coordinated control region of NOx and VOCs expanded, and the control region of VOCs decreased in size. The reduction of non-point-source emissions, such as fugitive VOCs and vehicles, was more useful for controlling regional photochemical pollution over northern China.

10 CFR 300.7 - Net emission reductions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... DEPARTMENT OF ENERGY CLIMATE CHANGE VOLUNTARY GREENHOUSE GAS REPORTING PROGRAM: GENERAL GUIDELINES § 300.7... practicable, on a full assessment and sum total of all changes in an entity's emissions, eligible avoided... include the annual changes in the total emissions of the entity, including the total emissions of each of...

10 CFR 300.7 - Net emission reductions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... DEPARTMENT OF ENERGY CLIMATE CHANGE VOLUNTARY GREENHOUSE GAS REPORTING PROGRAM: GENERAL GUIDELINES § 300.7... practicable, on a full assessment and sum total of all changes in an entity's emissions, eligible avoided... include the annual changes in the total emissions of the entity, including the total emissions of each of...

10 CFR 300.7 - Net emission reductions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... DEPARTMENT OF ENERGY CLIMATE CHANGE VOLUNTARY GREENHOUSE GAS REPORTING PROGRAM: GENERAL GUIDELINES § 300.7... practicable, on a full assessment and sum total of all changes in an entity's emissions, eligible avoided... include the annual changes in the total emissions of the entity, including the total emissions of each of...

10 CFR 300.7 - Net emission reductions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... DEPARTMENT OF ENERGY CLIMATE CHANGE VOLUNTARY GREENHOUSE GAS REPORTING PROGRAM: GENERAL GUIDELINES § 300.7... practicable, on a full assessment and sum total of all changes in an entity's emissions, eligible avoided... include the annual changes in the total emissions of the entity, including the total emissions of each of...

10 CFR 300.7 - Net emission reductions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... DEPARTMENT OF ENERGY CLIMATE CHANGE VOLUNTARY GREENHOUSE GAS REPORTING PROGRAM: GENERAL GUIDELINES § 300.7... practicable, on a full assessment and sum total of all changes in an entity's emissions, eligible avoided... include the annual changes in the total emissions of the entity, including the total emissions of each of...

Molten Metal Treatment by Salt Fluxing with Low Environmental Emissions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yogeshwar Sahai

2007-07-31

Abstract: Chlorine gas is traditionally used for fluxing of aluminum melt for removal of alkali and alkaline earth elements. However this results in undesirable emissions of particulate matter and gases such as HCl and chlorine, which are often at unacceptable levels. Additionally, chlorine gas is highly toxic and its handling, storage, and use pose risks to employees and the local community. Holding of even minimal amounts of chlorine necessitates extensive training for all plant employees. Fugitive emissions from chlorine usage within the plant cause accelerated corrosion of plant equipment. The Secondary Aluminum Maximum Achievable Control Technology (MACT) under the Cleanmore » Air Act, finalized in March 2000 has set very tough new limits on particulate matter (PM) and total hydrogen chloride emissions from aluminum melting and holding furnaces. These limits are 0.4 and 0.1 lbs per ton of aluminum for hydrogen chloride and particulate emissions, respectively. Assuming new technologies for meeting these limits can be found, additional requirements under the Clean Air Act (Prevention of Significant Deterioration and New Source Review) trigger Best Available Control Technology (BACT) for new sources with annual emissions (net emissions not expressed per ton of production) over specified amounts. BACT currently is lime coated bag-houses for control of particulate and HCl emissions. These controls are expensive, difficult to operate and maintain, and result in reduced American competitiveness in the global economy. Solid salt fluxing is emerging as a viable option for the replacement of chlorine gas fluxing, provided emissions can be consistently maintained below the required levels. This project was a cooperative effort between the Ohio State University and Alcoa to investigate and optimize the effects of solid chloride flux addition in molten metal for alkali impurity and non-metallic inclusion removal minimizing dust and toxic emissions and maximizing energy conservation. In this program, the salt metal interactions were studies and the emissions at laboratory scale at OSU were monitored. The goal of the project was to obtain a fundamental understanding, based on first principles, of the pollutant formation that occurs when the salts are used in furnaces. This information will be used to control process parameters so that emissions are consistently below the required levels. The information obtained in these experiments will be used in industrial furnaces at aluminum plants and which will help in optimizing the process.« less

Emission projections of the transport Sector in China: 2015-2040

NASA Astrophysics Data System (ADS)

Yan, L.

2016-12-01

Driven by the significant growth freight and passenger transport demand, transport sector has become a sector that is largely responsible for increases in emissions of atmospheric pollutants (NOx, CO, HC, PM2.5) in China. Figuring out the emission trend in China's transport sector has great influence on formulating emission reduction measures in the future. In this work, both on-road and off-road transport emissions in China were estimated from 2015 to 2040 for CO, NOx, HC and PM2.5. The projection was conducted based on on the energy consumption structure forecast from IEA (International Energy Agency), the future national average annual distance traveled per vehicle and fuel consumption per distance derived from simulation results of the Fuel Economy and Environmental Impact (FEEI) model. The results show that the ownership of on-road vehicles in China increases rapidly during 2015 to 2030 and then the growth slows down. Finally, the total amount reaches up to 522 million in 2040 in which 84.5% turns out to be light-duty vehicles. Because current control legislations for the transport sector in China will continue to be strengthened in the future, the total emissions of China's transport sector were projected to peak around 2030, due to the improvement of vehicle emission standard and the retirement of old vehicles are the most effective measures. The off-road transport will become the main contributor to emissions from transport sector in China since 2030. This work provides a new perspective to understand emissions from both on-road and off-road transport in China, which can support the achievement of improving air quality promised by the Chinese government. This work provides a new perspective to understand the emission trends of on-road and off-road transport sector in China from 2015 to 2040, which can support the achievement of the air quality goal promised by the Chinese government. Driven by the significant growth freight and passenger transport demand, transport sector has become a sector that is largely responsible for increases in emissions of atmospheric pollutants (NOx, CO, HC, PM2.5) in China. Figuring out the emission trend in China's transport sector has great influence on formulating emission reduction measures in the future. In this work, both on-road and off-road transport emissions in China were estimated from 2015 to 2040 for CO, NOx, HC and PM2.5. The projection was conducted based on on the energy consumption structure forecast from IEA (International Energy Agency), the future national average annual distance traveled per vehicle and fuel consumption per distance derived from simulation results of the Fuel Economy and Environmental Impact (FEEI) model. The results show that the ownership of on-road vehicles in China increases rapidly during 2015 to 2030 and then the growth slows down. Finally, the total amount reaches up to 522 million in 2040 in which 84.5% turns out to be light-duty vehicles. Because current control legislations for the transport sector in China will continue to be strengthened in the future, the total emissions of China's transport sector were projected to peak around 2030, due to the improvement of vehicle emission standard and the retirement of old vehicles are the most effective measures. The off-road transport will become the main contributor to emissions from transport sector in China since 2030. This work provides a new perspective to understand emissions from both on-road and off-road transport in China, which can support the achievement of improving air quality promised by the Chinese government. This work provides a new perspective to understand the emission trends of on-road and off-road transport sector in China from 2015 to 2040, which can support the achievement of the air quality goal promised by the Chinese government.

Precision control of eluted activity from a Sr/Rb generator for cardiac positron emission tomography.

PubMed

Klein, R; Adler, A; Beanlands, R S; deKemp, R A

2004-01-01

A rubidium-82 (/sup 82/Rb) elution system is described for use with clinical positron emission tomography. The system is self-calibrating with 1.4% repeatability, independent of generator activity and elution flow rate. Saline flow is switched between a /sup 82/Sr//sup 82/Rb generator and a bypass line to achieve a constant activity elution of /sup 82/Rb. In the present study, pulse width modulation (PWM) of a solenoid valve is compared to simple threshold control as a means to simulate a proportional valve. A predictive-corrective control algorithm is developed which produces a constant activity elution within the constraints of long feedback delay and short elution time. Accurate constant-activity elutions of 10-70% of the total generator activity were demonstrated using the threshold comparison control. The adaptive-corrective control of the PWM valve provided a substantial improvement in precision of the steady-state output.

High-resolution ammonia emissions inventories in Fujian, China, 2009-2015

NASA Astrophysics Data System (ADS)

Wu, Shui-Ping; Zhang, Yin-Ju; Schwab, James J.; Li, Yang-Fan; Liu, Yuan-Long; Yuan, Chung-Shin

2017-08-01

A high-resolution NH3 emission inventory was developed based on the corrected emission factors and county-level activity data. To provide model-ready emission input, the NH3 emission inventory was gridded for the modeling domain at 1 × 1 km resolution using source-based spatial surrogates and a GIS system. The best estimate of total NH3 emission for the province was 228.02 kt in 2015 with a percentage uncertainty of ±16.3%. Four major contributors were farmland ecosystem, livestock wastes, humans and waste treatment, which contributed 39.4%, 43.1%, 4.9%, and 4.2% of the total emissions, respectively. The averaged NH3 emission density for the whole region was 1.88 t km-2 yr-1 and the higher values were found in coastal areas with higher dense populations. The seasonal patterns, with higher emissions in summer, were consistent with the patterns of temperature and planting practices. From 2009 to 2015, annual NH3 emissions increased from 218.49 kt to 228.02 kt. All of these changes are insignificant compared to the estimated overall uncertainties in the analysis, but indicative of changes in the source categories over this period. Between 2009 and 2015, the largest changes occurred in human emissions and waste treatment plants, which were consistent with the process of rapid urbanization. Meanwhile, the decrease of emissions from pigs was slightly higher than the increased emissions from broilers and the increased emissions from meat goats and beef cattle due to the combine effects of increasingly stringent environmental requirements for pig farms and shift away from pork consumption to beef, chicken and mutton. The validity of the estimates was further evaluated using uncertainty analysis, comparison with previous studies, and correlation analysis between emission density and observed ground ammonia. The inventories reflect the changes in economic progress and environmental protection and can provide scientific basis for the establishment of effective PM2.5 control strategies.

Chemical and stable carbon isotopic composition of PM2.5 from on-road vehicle emissions in the PRD region and implication for vehicle emission control policy

NASA Astrophysics Data System (ADS)

Dai, S.; Bi, X.; Chan, L. Y.; He, J.; Wang, B.; Wang, X.; Sheng, G.; Fu, J.

2014-11-01

Vehicle emission is a major source of urban air pollution. In recent decade, the Chinese government has introduced a range of policies to reduce the vehicle emission. In order to understand the chemical characteristics of PM2.5 from on-road vehicle emission in the Pearl River Delta (PRD) region and to evaluate the effectiveness of control policies on vehicles emission, the emission factors of PM2.5 mass, elemental carbon (EC), organic carbon (OC), water-soluble organic carbon (WSOC), water-soluble inorganic ions (WSII), metal elements, organic compounds and stable carbon isotopic composition were measured in the Zhujiang Tunnel of Guangzhou, the PRD region of China in 2013. Emission factors of PM2.5 mass, OC, EC, and WSOC were 92.4, 16.7, 16.4, and 1.31 mg vehicle-1 km-1 respectively. Emission factors of WSII were 0.016 (F-) ~4.17 (Cl-) mg vehicle-1 km-1, totally contributing about 9.8% to the PM2.5 emissions. The sum of 27 measured metal elements accounted for 15.2% of the PM2.5 emissions. Fe was the most abundant metal element, with an emission factor of 3.91 mg vehicle-1 km-1. Emission factors of organic compounds including n-alkanes, PAHs, hopanes, and steranes were 91.9, 5.02, 32.0 and 7.59 μg vehicle-1 km-1, respectively. Stable carbon isotopic composition δ13C value was measured and it was -25.0‰ on average. An isotopic fractionation of 3.2‰ was found during fuel combustion. Compared with a previous study in Zhujiang Tunnel in year 2004, emission factors of PM2.5 mass, EC, OC, WSII except Cl-, and organic compounds decreased by 16.0-93.4%, which could be attributed to emission control policy from 2004 to 2013. However, emission factors of most of the metal elements increased significantly, which could be partially attributed to the changes in motor oil additives and vehicle condition. There are no mandatory national standards to limit metal content from vehicle emission, which should be a concern of the government. A snapshot of the 2013 characteristic emission of PM2.5 and its constituents from on-road vehicular fleet in the PRD region retrieved from our study was found to be useful for the assessment of past and future implementation of vehicle emission control policy.

Effects of Aftermarket Control Technologies on Gas and ...

EPA Pesticide Factsheets

Particulate matter (PM) originating from diesel combustion is a public health concern due to its association with adverse effects on respiratory and cardiovascular diseases and lung cancer. This study investigated emissions from three stationary diesel engines (gensets) with varying power output (230 kW, 400 kW, and 600 kW) at 50% and 90% load to determine concentrations of gaseous (GROS) and PM reactive oxygen species (PMROS). In addition, the influence of three modern emission control technologies on ROS emissions was evaluated: active and passive diesel particulate filters (A-DPF and P-DPF) and a diesel oxidation catalyst (DOC). PMROS made up 30-50% of the total ROS measured without aftermarket controls. All applied controls removed PMROS by more than 75% on average. However, the oxidative potential of PM downstream of these devices was not diminished at the same rate and particles surviving the A-PDF had an even higher oxidative potential on a per PM mass basis compared to the particles emitted by uncontrolled gensets. Further, the GROS as compared to PMROS emissions were not reduced with the same efficiency (<36%). GROS concentrations were highest with the DOC in use, indicating continued formation of GROS with this control. Correlation analyses showed that PMROS and to a lesser extent GROS have a good correlation with semi-volatile organic carbon (OC1) sub-fraction. In addition, results suggest that chemical composition, rather than PM size, is re

Methane emissions from Alaska Arctic tundra - An assessment of local spatial variability

NASA Technical Reports Server (NTRS)

Morrissey, L. A.; Livingston, G. P.

1992-01-01

The findings of an extensive midsummer survey of CH4 emissions measurements representing the Alaska Arctic tundra are presented. Variability in rates of emissions was similar in magnitude on local and regional scales, ranging from 0 to 286.5 mg/sq m/d overall and often varying across two orders of magnitude within 0.5 m distances. Primary control on rates of emission was determined by the substrate and position of the water table relative to the surface. Emission rates in the Arctic Foothills ranged from 0.2 mg/sq m/d for tussock tundra to 55.53 mg/sq m/d over wet meadows. Plant-mediated release of CH4 to the atmosphere was directly proportional to green leaf area and represented 92-98 percent of the total emission rates over vegetated sites. The results suggest the current published emission rates may have overestimated the contribution of boreal ecosystems to the global CH4 budget by several fold.

Spatial and temporal variability of greenhouse gas emissions from a small and shallow temperate lake

NASA Astrophysics Data System (ADS)

Praetzel, Leandra; Schmiedeskamp, Marcel; Broder, Tanja; Hüttemann, Caroline; Jansen, Laura; Metzelder, Ulrike; Wallis, Ronya; Knorr, Klaus-Holger; Blodau, Christian

2017-04-01

Small inland waters (< 1 km2) have recently been discovered as significant sources and sinks in the global carbon cycle because they cover larger areas than previously assumed and exhibit a higher metabolic activity than larger lakes. They are further expected to be susceptible to changing climate conditions. So far, little is known about the spatial and temporal variability of carbon dioxide (CO2) and methane (CH4) emissions and in-lake dynamics of CH4 production and oxidation in small, epilimnetic lakes in the temperate zone. Of particular interest is the potential occurrence of "hot spots" and "hot moments" that could contribute significantly to total emissions. To address this knowledge gap, we determined CO2 and CH4 emissions and dynamics to identify their controlling environmental factors in a polymictic small (1.4 ha) and shallow (max. depth approx. 1.5 m) crater lake ("Windsborn") in the Eifel uplands in south-west Germany. As Lake Windsborn has a small catchment area (8 ha) and no surficial inflows, it serves well as a model system for the identification of factors and processes controlling emissions. In 2015, 2016 and 2017 we measured CO2 and CH4 gas fluxes with different techniques across the sediment/water and water/atmosphere interface. Atmospheric exchange was measured using mini-chambers equipped with CO2 sensors and with an infra-red greenhouse gas analyzer for high temporal resolution flux measurements. Ebullition of CH4 was quantified with funnel traps. Sediment properties were examined using pore-water peepers. All measurements were carried out along a transect covering both littoral and central parts of the lake. Moreover, a weather station on a floating platform in the center of the lake recorded meteorological data as well as CO2 concentration in different depths of the water column. So far, Lake Windsborn seems to be a source for both CO2 and CH4 on an annual scale. CO2 emissions generally increased from spring to summer. Even though CO2 uptake could be observed during some periods in spring and fall, CO2 emissions in the summer exceeded the uptake. CO2 and CH4 emissions also appeared to be spatially variable between littoral areas and the inner lake. Shallow areas turned out to be "hot spots" of CO2 emissions whereas CH4 emissions were - against our expectations - highest in the center of the lake. Moreover, CH4 ebullition contributed substantially to total CH4 emissions. Our results show the importance of spatially and temporally highly resolved long-term measurements of greenhouse gas emissions and of potential controlling factors to address diurnal, seasonal and inter-annual variability as well as possible feedbacks to climate change.

Analyzing and forecasting CO2 emission reduction in China's steel industry

NASA Astrophysics Data System (ADS)

Gao, Chengkang; Wang, Dan; Zhao, Baohua; Chen, Shan; Qin, Wei

2015-03-01

Recent measures of carbon dioxide emissions from the steel industry of China have indicated a high rate of total CO2 emissions from the industry, even compared to the rest of the world. So, CO2 emission reduction in China's steel industry was analyzed, coupling the whole process and scenarios analysis. First, assuming that all available advanced technologies are almost adopted, this study puts forward some key potential-sectors and explores an optimal technical route for reducing CO2 emissions from the Chinese steel industry based on whole process analysis. The results show that in the stages of coking, sintering, and iron making, greater potential for reducing emissions would be fulfilled by taking some technological measures. If only would above well-developed technologies be fulfill, the CO2 emissions from 5 industry production stages would be reduced substantially, and CO2 emissions per ton of steel could be decreased to 1.24 (ton/ton-steel) by 2020. At the same time, the scenarios analysis indicates that if mature carbon-reducing technologies are adopted, and if the difference between steel output growth rate and the GDP growth rate could be controlled below 3%, CO2 emissions from China's steel industry would approach the goal of reducing CO2 emissions per GDP unit by 40%-45% of the 2005 level by 2020. This indicates that the focus of carbon dioxide emissions reduction in China lies in policy adjustments in order to enhance technological application, and lies in reasonably controlling the pace of growth of GDP and steel output.

Laboratory estimates of trace gas emissions following surface application and injection of cattle slurry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Flessa, H.; Beese, F.

2000-02-01

Applying cattle slurry to soil may induce emissions of the greenhouse gases N{sub 2}O and CH{sub 4}. Their objective was to determine the effects of different application techniques (surface application and slit injection) of cattle (Bostaurus) slurry on the decomposition of slurry organic matter and the emissions of N{sub 2}O and CH{sub 4}. The effects of slurry application (43.6 m{sup 3} ha{sup {minus}1}) were studied for 9 wk under controlled laboratory conditions using a soil microcosm system with automated monitoring of the CO{sub 2}, N{sub 2}O, and CH{sub 4} fluxes. The soil used was a silty loam (Ap horizon ofmore » a cambisol) with a constant water-filled pore space of 67% during the experiment. About 38% of the organic matter applied with the slurry was decomposed within 9 wk. Production of CO{sub 2} was not affected by the application technique. Emissions of N{sub 2}O and CH{sub 4} from the injected slurry were significantly higher than from the surface-applied slurry, probably because of restricted aeration at the injected-slurry treatment. Total N{sub 2}O-N emissions were 0.2% (surface application) and 3.3% (slit injection) of the slurry N added. Methane emission occurred only during the first few days following application. The total net flux of CH{sub 4}-C for 2 wk was {minus}12 g ha{sup {minus}1} for the control (CH{sub 4} uptake), 2 g ha{sup {minus}1} for the surface-applied slurry, and 39 g ha{sup {minus}1} for the injected slurry. Slurry injection, which is recommended to reduce NH{sub 3} volatilization, appears to increase emissions of the greenhouse gases N{sub 2}O and CH{sub 4} from the fertilized fields.« less

Factors controlling nitrous oxide emissions from a full-scale activated sludge system in the tropics.

PubMed

Brotto, Ariane C; Kligerman, Débora C; Andrade, Samara A; Ribeiro, Renato P; Oliveira, Jaime L M; Chandran, Kartik; de Mello, William Z

2015-08-01

Despite interest in characterizing nitrous oxide (N2O) emissions from wastewater treatment plants (WWTPs) in several parts of the globe, there are few studies in tropical zones. This study focus on the contribution of the scientific knowledge of anthropogenic nitrogen greenhouse gas emissions to climate change in tropical countries, investigating factors controlling N2O emissions in a non-biological nitrogen removal municipal WWTP. In terms of operational parameters, dissolved oxygen (DO) concentrations displayed a biphasic impact on N2O production and emission, with the highest emission at DO of 2.0 mg O2 L(-1). The low solids retention time of 3 days also played a significant role, leading to nitrite accumulation, which is an important trigger for N2O production during nitrification. Furthermore, other factor especially important for tropical countries, namely, temperature, also had a positive correlation with N2O production. Emission factors estimated for this study were 0.12 (0.02-0.31)% of the influent total nitrogen load and 8.1 (3-17) g N2O person(-1) year(-1), 2.5 times higher than currently proposed emission factors. Therefore, the highly variability and dependence on operational parameters reinforce the use of a single emission factor is inadequate, especially for developing countries with limited or variable extent of biological wastewater treatment and in regions of the world with widely varying climate patterns.

Correction of Measured Taxicab Exhaust Emission Data Based on Cmem Modle

NASA Astrophysics Data System (ADS)

Li, Q.; Jia, T.

2017-09-01

Carbon dioxide emissions from urban road traffic mainly come from automobile exhaust. However, the carbon dioxide emissions obtained by the instruments are unreliable due to time delay error. In order to improve the reliability of data, we propose a method to correct the measured vehicles' carbon dioxide emissions from instrument based on the CMEM model. Firstly, the synthetic time series of carbon dioxide emissions are simulated by CMEM model and GPS velocity data. Then, taking the simulation data as the control group, the time delay error of the measured carbon dioxide emissions can be estimated by the asynchronous correlation analysis, and the outliers can be automatically identified and corrected using the principle of DTW algorithm. Taking the taxi trajectory data of Wuhan as an example, the results show that (1) the correlation coefficient between the measured data and the control group data can be improved from 0.52 to 0.59 by mitigating the systematic time delay error. Furthermore, by adjusting the outliers which account for 4.73 % of the total data, the correlation coefficient can raise to 0.63, which suggests strong correlation. The construction of low carbon traffic has become the focus of the local government. In order to respond to the slogan of energy saving and emission reduction, the distribution of carbon emissions from motor vehicle exhaust emission was studied. So our corrected data can be used to make further air quality analysis.

Numerical simulations for the sources apportionment and control strategies of PM2.5 over Pearl River Delta, China, part I: Inventory and PM2.5 sources apportionment.

PubMed

Huang, Yeqi; Deng, Tao; Li, Zhenning; Wang, Nan; Yin, Chanqin; Wang, Shiqiang; Fan, Shaojia

2018-09-01

This article uses the WRF-CMAQ model to systematically study the source apportionment of PM 2.5 under typical meteorological conditions in the dry season (November 2010) in the Pearl River Delta (PRD). According to the geographical location and the relative magnitude of pollutant emission, Guangdong Province is divided into eight subdomains for source apportionment study. The Brute-Force Method (BFM) method was implemented to simulate the contribution from different regions to the PM 2.5 pollution in the PRD. Results show that the industrial sources accounted for the largest proportion. For emission species, the total amount of NO x and VOC in Guangdong Province, and NH 3 and VOC in Hunan Province are relatively larger. In Guangdong Province, the emission of SO 2 , NO x and VOC in the PRD are relatively larger, and the NH 3 emissions are higher outside the PRD. In northerly-controlled episodes, model simulations demonstrate that local emissions are important for PM 2.5 pollution in Guangzhou and Foshan. Meanwhile, emissions from Dongguan and Huizhou (DH), and out of Guangdong Province (SW) are important contributors for PM 2.5 pollution in Guangzhou. For PM 2.5 pollution in Foshan, emissions in Guangzhou and DH are the major contributors. In addition, high contribution ratio from DH only occurs in severe pollution periods. In southerly-controlled episode, contribution from the southern PRD increases. Local emissions and emissions from Shenzhen, DH, Zhuhai-Jiangmen-Zhongshan (ZJZ) are the major contributors. Regional contribution to the chemical compositions of PM 2.5 indicates that the sources of chemical components are similar to those of PM 2.5 . In particular, SO 4 2- is mainly sourced from emissions out of Guangdong Province, while the NO 3- and NH 4+ are more linked to agricultural emissions. Copyright © 2018 Elsevier B.V. All rights reserved.

Impact of elevated CO2, water table, and temperature changes on CO2 and CH4 fluxes from arctic tundra soils

NASA Astrophysics Data System (ADS)

Zona, Donatella; Haynes, Katherine; Deutschman, Douglas; Bryant, Emma; McEwing, Katherine; Davidson, Scott; Oechel, Walter

2015-04-01

Large uncertainties still exist on the response of tundra C emissions to future climate due, in part, to the lack of understanding of the interactive effects of potentially controlling variables on C emissions from Arctic ecosystems. In this study we subjected 48 soil cores (without active vegetation) from dominant arctic wetland vegetation types, to a laboratory manipulation of elevated atmospheric CO2, elevated temperature, and altered water table, representing current and future conditions in the Arctic for two growing seasons. To our knowledge this experiment comprised the most extensively replicated manipulation of intact soil cores in the Arctic. The hydrological status of the soil was the most dominant control on both soil CO2 and CH4 emissions. Despite higher soil CO2 emission occurring in the drier plots, substantial CO2 respiration occurred under flooded conditions, suggesting significant anaerobic respirations in these arctic tundra ecosystems. Importantly, a critical control on soil CO2 and CH4 fluxes was the original vascular plant cover. The dissolved organic carbon (DOC) concentration was correlated with cumulative CH4 emissions but not with cumulative CO2 suggesting C quality influenced CH4 production but not soil CO2 emissions. An interactive effect between increased temperature and elevated CO2 on soil CO2 emissions suggested a potential shift of the soils microbial community towards more efficient soil organic matter degraders with warming and elevated CO2. Methane emissions did not decrease over the course of the experiment, even with no input from vegetation. This result indicated that CH4 emissions are not carbon limited in these C rich soils. Overall CH4 emissions represented about 49% of the sum of total C (C-CO2 + C-CH4) emission in the wet treatments, and 15% in the dry treatments, representing a dominant component of the overall C balance from arctic soils.

Assessing global radiative forcing due to regional emissions of tropospheric ozone precursors: a step towards climate credit for ozone reductions

NASA Astrophysics Data System (ADS)

Mauzerall, D. L.; Naik, V.; Horowitz, L. W.; Schwarzkopf, D.; Ramaswamy, V.; Oppenheimer, M.

2005-05-01

Carbon dioxide emissions from fossil-fuel consumption are presented for the five Asian countries that are among the global leaders in anthropogenic carbon emissions: China (13% of global total), Japan (5% of global total), India (5% of global total), South Korea (2% of global total), and Indonesia (1% of global total). Together, these five countries represent over a quarter of the world's fossil-fuel based carbon emissions. Moreover, these countries are rapidly developing and energy demand has grown dramatically in the last two decades. A method is developed to estimate the spatial and seasonal flux of fossil-fuel consumption, thereby greatly improving the temporal and spatial resolution of anthropogenic carbon dioxide emissions. Currently, only national annual data for anthropogenic carbon emissions are available, and as such, no understanding of seasonal or sub-national patterns of emissions are possible. This methodology employs fuel distribution data from representative sectors of the fossil-fuel market to determine the temporal and spatial patterns of fuel consumption. These patterns of fuel consumption are then converted to patterns of carbon emissions. The annual total emissions estimates produced by this method are consistent to those maintained by the United Nations. Improved estimates of temporal and spatial resolution of the human based carbon emissions allows for better projections about future energy demands, carbon emissions, and ultimately the global carbon cycle.

Using the Hestia bottom-up FFCO2 emissions estimation to identify drivers and hotspots in urban areas

NASA Astrophysics Data System (ADS)

Rao, P.; Patarasuk, R.; Gurney, K. R.; o'Keefe, D.; Song, Y.; Huang, J.; Buchert, M.; Lin, J. C.; Mendoza, D. L.; Ehleringer, J. R.; Eldering, A.; Miller, C. E.; Duren, R. M.

2015-12-01

Urban areas occupy 3% of the earth's land surface and generate 75% of the fossil fuel carbon dioxide (FFCO2) emissions. We report on the application of the Hestia Project to the Salt Lake County (SLC) and Los Angeles (LA) domains. Hestia quantifies FFCO2 in fine space-time detail across urban domains using a scientific "bottom-up" approach. We explore the utility of the Hestia to inform both urbanization science and greenhouse gas (GHG) mitigation policy. We focus on the residential sector in SLC and the onroad sector in LA as these sectors are large emissions contributors in each locale, and local governments have some authority and policy levers to mitigate these emissions. Multiple regression using sociodemographic data across SLC census block-groups shows that per capita income exhibits a positive relationship with FFCO2 emissions while household size exhibits a negative relationship, after controlling for total population. Housing units per area (i.e., compact development) has little effect on FFCO2 emissions. Rising income in the high-income group has twice as much impact on the emissions as the low-income group. Household size for the low-income group has four times the impact on the emissions as the high-income group. In LA, onroad FFCO2 emissions account for 49% of total emissions, of which 41% is from arterials (intermediate road class). Arterials also have the largest carbon emissions intensity - FFCO2/vehicle distance travelled (VKT) - possibly from high traffic congestion and fleet composition. Non-interstate hotspot emissions (> 419 tC ln-km-1) are equally dominated by particular arterials and collectors (lowest road class) though collectors have a higher VKT. These hotspots occur largely in LA (67%) and Orange (18%) counties and provide targeted information for onroad emissions reduction. Using Hestia to identify FFCO2 emissions drivers and hotpots can aid state and local policy makers in planning the most effective GHG reductions.

Balancing effluent quality, economic cost and greenhouse gas emissions during the evaluation of (plant-wide) control/operational strategies in WWTPs.

PubMed

Flores-Alsina, Xavier; Arnell, Magnus; Amerlinck, Youri; Corominas, Lluís; Gernaey, Krist V; Guo, Lisha; Lindblom, Erik; Nopens, Ingmar; Porro, Jose; Shaw, Andy; Snip, Laura; Vanrolleghem, Peter A; Jeppsson, Ulf

2014-01-01

The objective of this paper was to show the potential additional insight that result from adding greenhouse gas (GHG) emissions to plant performance evaluation criteria, such as effluent quality (EQI) and operational cost (OCI) indices, when evaluating (plant-wide) control/operational strategies in wastewater treatment plants (WWTPs). The proposed GHG evaluation is based on a set of comprehensive dynamic models that estimate the most significant potential on-site and off-site sources of CO₂, CH₄ and N₂O. The study calculates and discusses the changes in EQI, OCI and the emission of GHGs as a consequence of varying the following four process variables: (i) the set point of aeration control in the activated sludge section; (ii) the removal efficiency of total suspended solids (TSS) in the primary clarifier; (iii) the temperature in the anaerobic digester; and (iv) the control of the flow of anaerobic digester supernatants coming from sludge treatment. Based upon the assumptions built into the model structures, simulation results highlight the potential undesirable effects of increased GHG production when carrying out local energy optimization of the aeration system in the activated sludge section and energy recovery from the AD. Although off-site CO₂ emissions may decrease, the effect is counterbalanced by increased N₂O emissions, especially since N₂O has a 300-fold stronger greenhouse effect than CO₂. The reported results emphasize the importance and usefulness of using multiple evaluation criteria to compare and evaluate (plant-wide) control strategies in a WWTP for more informed operational decision making. © 2013.

40 CFR 63.2354 - What performance tests, design evaluations, and performance evaluations must I conduct?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., appendix A, to determine compliance with the organic HAP or TOC emission limit, you may use EPA Method 18... formaldehyde control efficiency as a surrogate for total organic HAP or TOC efficiency, or at the outlet of a...

40 CFR 63.139 - Process wastewater provisions-control devices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... chemical reaction with the scrubbing liquid or achieve an outlet total organic compound concentration, less... National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical... reaction kinetics of the constituents with the scrubbing liquid. The design evaluation shall establish the...

40 CFR 63.139 - Process wastewater provisions-control devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chemical reaction with the scrubbing liquid or achieve an outlet total organic compound concentration, less... National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical... reaction kinetics of the constituents with the scrubbing liquid. The design evaluation shall establish the...

40 CFR 63.139 - Process wastewater provisions-control devices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... chemical reaction with the scrubbing liquid or achieve an outlet total organic compound concentration, less... National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical... reaction kinetics of the constituents with the scrubbing liquid. The design evaluation shall establish the...

40 CFR 63.139 - Process wastewater provisions-control devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chemical reaction with the scrubbing liquid or achieve an outlet total organic compound concentration, less... National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical... reaction kinetics of the constituents with the scrubbing liquid. The design evaluation shall establish the...

40 CFR 63.139 - Process wastewater provisions-control devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... chemical reaction with the scrubbing liquid or achieve an outlet total organic compound concentration, less... National Emission Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical... reaction kinetics of the constituents with the scrubbing liquid. The design evaluation shall establish the...

Large increases in Arctic biogenic volatile emissions are a direct effect of warming

NASA Astrophysics Data System (ADS)

Kramshøj, Magnus; Vedel-Petersen, Ida; Schollert, Michelle; Rinnan, Åsmund; Nymand, Josephine; Ro-Poulsen, Helge; Rinnan, Riikka

2016-05-01

Biogenic volatile organic compounds are reactive gases that can contribute to atmospheric aerosol formation. Their emission from vegetation is dependent on temperature and light availability. Increasing temperature, changing cloud cover and shifting composition of vegetation communities can be expected to affect emissions in the Arctic, where the ongoing climate changes are particularly severe. Here we present biogenic volatile organic compound emission data from Arctic tundra exposed to six years of experimental warming or reduced sunlight treatment in a randomized block design. By separately assessing the emission response of the whole ecosystem, plant shoots and soil in four measurements covering the growing season, we have identified that warming increased the emissions directly rather than via a change in the plant biomass and species composition. Warming caused a 260% increase in total emission rate for the ecosystem and a 90% increase in emission rates for plants, while having no effect on soil emissions. Compared to the control, reduced sunlight decreased emissions by 69% for the ecosystem, 61-65% for plants and 78% for soil. The detected strong emission response is considerably higher than observed at more southern latitudes, emphasizing the high temperature sensitivity of ecosystem processes in the changing Arctic.

Impact of future Arctic shipping on high-latitude black carbon deposition (Invited)

NASA Astrophysics Data System (ADS)

Corbett, J. J.; Browse, J.; Carslaw, K. S.; Schmidt, A.

2013-12-01

The retreat of Arctic sea-ice has led to renewed calls to exploit Arctic shipping routes. The diversion of ship traffic through the Arctic will shorten shipping routes and possibly reduce global shipping emissions. However, deposition of black carbon (BC) aerosol emitted by additional Arctic ships could cause a reduction in the albedo of snow and ice, accelerating snow-melt and sea-ice loss. We use recently compiled Arctic shipping emission inventories for 2004 and 2050 together with a global aerosol microphysics model GLOMAP coupled to the chemical transport model TOMCAT to quantify the contribution of future Arctic shipping to high-latitude BC deposition. Emission rates of SOx (SO2 and SO4) and particulate matter (PM) were estimated for 2050 under both business-as-usual and high-growth scenarios. BC particles are assumed to be water-insoluble at emission but can become active in cloud drop formation through soluble material accumulation. After BC particles become cloud-active they are more efficiently wet scavenged, which accounts for 80% of modeled BC deposition. Current-day Arctic shipping contributes 0.3% to the BC mass deposited north of 60N (250 Gg). About 50% of modelled BC deposition is on open ocean, suggesting that current Arctic ship traffic may not significantly contribute to BC deposition on central Arctic sea ice. However, 6 - 8% of deposited BC on the west coast of Greenland originates from local ship traffic. Moreover, in-Arctic shipping contributes some 32% to high-latitude ship-sourced deposition despite accounting for less than 1.0% of global shipping emissions. This suggests that control of in-Arctic shipping BC emissions could yield greater decrease in high-latitude BC deposition than a similar control strategy applied only to the extra-Arctic shipping industry. Arctic shipping in 2050 will contribute less than 1% to the total BC deposition north of 60N due to the much greater relative contribution of BC transported from non-shipping sources at lower-latitudes (with a maximum of about 5%, considering upper bound estimates for transport). In the BAU and HiG scenarios, the total BC deposition averaged north of 60N from Arctic shipping remains small, increasing to only 0.4% and 0.7%, respectively. Several mitigation strategies confirmed that extra-Arctic sources other than shipping contribute significantly more to BC deposition than Arctic shipping, and that regulation solely aimed at the Arctic shipping industry is an insufficient control on high-latitude BC deposition. An exception is the impact of local shipping near the vulnerable Greenland ice-sheet. Over Greenland the deposited BC mass attributable to high-growth shipping emissions in 2050 is significantly higher (10-15%) than over Arctic sea-ice. The increase in local BC deposition over Greenland can be mitigated by a 10% decrease in North American BC emissions, but additional controls over distant stationary sources should be considered alongside international agreements controlling shipping emissions to achieve desired Arctic BC deposition reductions.

Toward better understanding and feasibility of controlling greenhouse gas emissions from treatment of industrial wastewater with activated sludge.

PubMed

Chen, Wei-Hsiang; Yang, Jun-Hong; Yuan, Chung-Shin; Yang, Ying-Hsien

2016-10-01

Wastewater treatment plants (WWTPs) have been recognized as important sources for anthropogenic greenhouse gas (GHG) emission. The objective of the study was to thoroughly investigate a typical industrial WWTP in southern Taiwan in winter and summer which possesses the emission factors close to those reported values, with the analyses of emission factors, mass fluxes, fugacity, lab-scale in situ experiments, and impact assessment. The activated sludge was the important source in winter and summer, and nitrous oxide (N 2 O) was the main contributor (e.g., 57 to 91 % of total GHG emission in a unit of kg carbon dioxide-equivalent/kg chemical oxygen demand). Albeit important for the GHGs in the atmosphere, the fractional contribution of the GHG emission to the carbon or nitrogen removal in wastewater treatment was negligible (e.g., less than 1.5 %). In comparison with the sludge concentration or retention time, adjusting the aeration rate was more effective to diminish the GHG emission in the activated sludge without significantly affecting the treated water quality. When the aeration rate in the activated sludge simulation was reduced by 75 %, the mass flux of N 2 O could be diminished by up to 53 % (from 9.6 to 4.5 mg/m 2 -day). The total emission in the WWTP (including carbon dioxide, methane, and N 2 O) would decrease by 46 % (from 0.67 to 0.36 kg CO 2 -equiv/kg COD). However, the more important benefit of changing the aeration rate was lowering the energy consumption in operation of the WWTP, as the fractional contribution of pumping to the total emission from the WWTP ranged from 46 to 93 % within the range of the aeration rate tested. Under the circumstance in which reducing the burden of climate change is a global campaign, the findings provide insight regarding the GHG emission from treatment of industrial wastewater and the associated impact on the treatment performance and possible mitigation strategies by operational modifications.

Seasonal and species-specific response of VOC emissions by Mediterranean woody plant to elevated ozone concentrations

NASA Astrophysics Data System (ADS)

Llusià, J.; Peñuelas, J.; Gimeno, B. S.

Although certain factors controlling plant emission rates of volatile organic compounds (VOCs) are reasonably well understood, the influence of elevated ozone concentrations as abiotic stress is mostly unknown. Therefore, we studied the effects of ozone concentrations on seasonal biogenic volatile organic compound (BVOC) emissions by different Mediterranean plant species in open top chambers (OTC). Three ozone treatments were established: filtered air (F), non-filtered air (NF), and fumigated air (NF+) adding 40 nl l -1 of ozone over NF. We studied the response of VOC emission in saplings of four Mediterranean woody plant species and subspecies: Ceratonia siliqua L., Olea europaea L., Quercus ilex spp. ilex L., and Quercus ilex spp. rotundifolia L. as representative of natural Mediterranean vegetation. No visible symptoms were detected on the leaves. No significant effect was found on net photosynthetic rates or stomatal conductance except for an increase in net photosynthetic rates in Quercus ilex ilex in spring and summer and an overall slight increase in Quercus ilex rotundifolia. Emissions of the total VOCs from Ceratonia siliqua in summer, and from Olea europaea and Quercus ilex rotundifolia in spring increased in ozone fumigated OTC in comparison with F or NF OTC. Decreased emissions were found in Quercus ilex rotundifolia in summer. There were no significant differences between ozone fumigation treatments for the other plant species and seasons. When considering particular VOCs, the results were also variable among species and time of the year. While α-pinene emissions decreased with ozone fumigation in Olea europaea, α-pinene and limonene emissions increased in Quercus ilex ilex. The responses of these particular VOCs did not always match the responses of total VOCs. In spite of this strong variability, when considering overall annual data for all species and seasons, there were increased net photosynthetic rates (37%) and limonene (95%) and total VOC (45%) emission rates in ozone-fumigated plants, whereas stomatal conductance did not change. Since VOCs are precursors of ozone, the increase in BVOC emission as a consequence of elevated tropospheric ozone concentrations may lead to positive feedback mechanisms in ozone formation.

Combination of biodiesel-ethanol-diesel fuel blend and SCR catalyst assembly to reduce emissions from a heavy-duty diesel engine.

PubMed

Shi, Xiaoyan; Yu, Yunbo; He, Hong; Shuai, Shijin; Dong, Hongyi; Li, Rulong

2008-01-01

In this study, the efforts to reduce NOx and particulate matter (PM) emissions from a diesel engine using both ethanol-selective catalytic reduction (SCR) of NOx over an Ag/Al2O3 catalyst and a biodiesel-ethanol-diesel fuel blend (BE-diesel) on an engine bench test are discussed. Compared with diesel fuel, use of BE-diesel increased PM emissions by 14% due to the increase in the soluble organic fraction (SOF) of PM, but it greatly reduced the Bosch smoke number by 60%-80% according to the results from 13-mode test of European Stationary Cycle (ESC) test. The SCR catalyst was effective in NOx reduction by ethanol, and the NOx conversion was approximately 73%. Total hydrocarbons (THC) and CO emissions increased significantly during the SCR of NOx process. Two diesel oxidation catalyst (DOC) assemblies were used after Ag/Al2O3 converter to remove CO and HC. Different oxidation catalyst showed opposite effect on PM emission. The PM composition analysis revealed that the net effect of oxidation catalyst on total PM was an integrative effect on SOF reduction and sulfate formation of PM. The engine bench test results indicated that the combination of BE-diesel and a SCR catalyst assembly could provide benefits for NOx and PM emissions control even without using diesel particle filters (DPFs).

SOA Formation Potential of Emissions from Soil and Leaf Litter

NASA Astrophysics Data System (ADS)

Faiola, C. L.; Vanderschelden, G. S.; Wen, M.; Cobos, D. R.; Jobson, B. T.; VanReken, T. M.

2013-12-01

In the United States, emissions of volatile organic compounds (VOCs) from natural sources exceed all anthropogenic sources combined. VOCs participate in oxidative chemistry in the atmosphere and impact the concentrations of ozone and particulate material. The formation of secondary organic aerosol (SOA) is particularly complex and is frequently underestimated using state-of-the-art modeling techniques. We present findings that suggest emissions of important SOA precursors from soil and leaf litter are higher than current inventories would suggest, particularly under conditions typical of Fall and Spring. Soil and leaf litter samples were collected at Big Meadow Creek from the University of Idaho Experimental Forest. The dominant tree species in this area of the forest are ponderosa pine, Douglas-fir, and western larch. Samples were transported to the laboratory and housed within a 0.9 cubic meter Teflon dynamic chamber where VOC emissions were continuously monitored with a GC-FID-MS and PTR-MS. Aerosol was generated from soil and leaf litter emissions by pumping the emissions into a 7 cubic meter Teflon aerosol growth chamber where they were oxidized with ozone in the absence of light. The evolution of particle microphysical and chemical characteristics was monitored over the following eight hours. Particle size distribution and chemical composition were measured with a SMPS and HR-ToF-AMS respectively. Monoterpenes dominated the emission profile with emission rates up to 283 micrograms carbon per meter squared per hour. The dominant monoterpenes emitted were beta-pinene, alpha-pinene, and delta-3-carene in descending order. The composition of the SOA produced was similar to biogenic SOA formed from oxidation of ponderosa pine emissions and alpha-pinene. Measured soil/litter monoterpene emission rates were compared with modeled canopy emissions. Results suggest that during fall and spring when tree emissions are lower, monoterpene emissions within forests may be dominated by soil/litter emissions--soil/litter monoterpene emissions in spring could contribute up to 63% of total forest emissions. If this is the case, a significant portion of total forest monoterpene emission rates would be controlled by factors that affect soil/litter emissions rather than factors that affect plant emissions.

Four years (2011-2015) of total gaseous mercury measurements from the Cape Verde Atmospheric Observatory

NASA Astrophysics Data System (ADS)

Read, Katie A.; Neves, Luis M.; Carpenter, Lucy J.; Lewis, Alastair C.; Fleming, Zoe L.; Kentisbeer, John

2017-04-01

Mercury is a chemical with widespread anthropogenic emissions that is known to be highly toxic to humans, ecosystems and wildlife. Global anthropogenic emissions are around 20 % higher than natural emissions and the amount of mercury released into the atmosphere has increased since the industrial revolution. In 2005 the European Union and the United States adopted measures to reduce mercury use, in part to offset the impacts of increasing emissions in industrialising countries. The changing regional emissions of mercury have impacts on a range of spatial scales. Here we report 4 years (December 2011-December 2015) of total gaseous mercury (TGM) measurements at the Cape Verde Observatory (CVO), a global WMO-GAW station located in the subtropical remote marine boundary layer. Observed total gaseous mercury concentrations were between 1.03 and 1.33 ng m-3 (10th, 90th percentiles), close to expectations based on previous interhemispheric gradient measurements. We observe a decreasing trend in TGM (-0.05 ± 0.04 ng m-3 yr-1, -4.2 % ± 3.3 % yr-1) over the 4 years consistent with the reported decrease of mercury concentrations in North Atlantic surface waters and reductions in anthropogenic emissions. The decrease was more visible in the summer (July-September) than in the winter (December-February), when measurements were impacted by air from the African continent and Sahara/Sahel regions. African air masses were also associated with the highest and most variable TGM concentrations. We suggest that the less pronounced downward trend inclination in African air may be attributed to poorly controlled anthropogenic sources such as artisanal and small-scale gold mining (ASGM) in West Africa.

The Relationship Between Emissions and Economic Growth for SO2, CO2, and BC

NASA Astrophysics Data System (ADS)

Ru, M.; Shindell, D. T.; Tao, S.; Zhong, Q.; Seltzer, K.

2017-12-01

We characterize the relationship between per person emissions of SO2, CO2, and black carbon (BC) and income using a global country-level emission inventory. Pollutant emissions of SO2 and BC from the power, industry, and transportation sectors largely follow an Environmental Kuznets Curve (EKC) pattern with peak emissions at income levels between 10,000 and 100,000 USD per capita. However, for CO2, any estimated turnover income is extremely high and unlikely to be reached in the near future in power, industry, and transportation. Residential emissions show a negatively sloped linear relationship for BC, a small positive slope for CO2, and a fairly flat trajectory for SO2. For the EKC-like trajectories, "turning point" incomes for each sector and pollutant are related to technological advances and the effectiveness of emission controls. These results suggest that policy targeting technological advances and emission controls could change future pathways by affecting the "turning point" incomes. For the linear trajectories in the residential sector, we show that transitions from biomass fuel to coal in low-income countries and from coal to natural gas in middle and high-income countries, in concert with electrification levels, are the main factors governing slopes. Thus, the three pollutants show different income-emission trajectories based on the sum of the four major sectors, and the residential sector in particular has a unique relationship with income growth. As one of the first studies to analyze historical emission trajectories of BC, we find that BC differs from SO2 and CO2 because of its significantly earlier turnover in the power and industry sectors due to control policies. Total BC emissions trajectories follow a unique shape due to the combination of linearly decreasing residential emissions with EKC-like patterns in industry and transportation. We compare these trajectories to those in three Integrated Assessment Models (IAMs), GCAM, AIM, and MESSAGE, finding large differences for residential sector trajectories and earlier estimations of turnover incomes in the IAMs. Users of IAMs should consider the assumptions underlying projected emissions in light of this historical analysis, especially the apparently optimistic turnover incomes and residential sector emissions.

Global Thermal Power Plants Database: Unit-Based CO2, SO2, NOX and PM2.5 Emissions in 2010

NASA Astrophysics Data System (ADS)

Tong, D.; Qiang, Z.; Davis, S. J.

2016-12-01

There are more than 30,000 thermal power plants now operating worldwide, reflecting a tremendously diverse infrastructure that includes units burning oil, natural gas, coal and biomass and ranging in capacity from <1MW to >1GW. Although the electricity generated by this infrastructure is vital to economic activities across the world, it also produces more CO2 and air pollution emissions than any other industry sector. Here we present a new database of global thermal power-generating units and their emissions as of 2010, GPED (Global Power Emissions Database), including the detailed unit information of installed capacity, operation year, geographic location, fuel type and control measures for more than 70000 units. In this study, we have compiled, combined, and harmonized the available underlying data related to thermal power-generating units (e.g. eGRID of USA, CPED of China and published Indian power plants database), and then analyzed the generating capacity, capacity factor, fuel type, age, location, and installed pollution-control technology in order to determine those units with disproportionately high levels of emissions. In total, this work is of great importance for improving spatial distribution of global thermal power plants emissions and exploring their environmental impacts at global scale.

Emission profiles of polychlorinated dibenzodioxins, polychlorinated dibenzofurans (PCDD/Fs), dioxin-like PCBs and hexachlorobenzene (HCB) from secondary metallurgy industries in Portugal.

PubMed

Antunes, Pedro; Viana, Paula; Vinhas, Tereza; Rivera, J; Gaspar, Elvira M S M

2012-09-01

This paper reports, for the first time, a study of dioxin emissions from 10 siderurgies and metallurgies, secondary copper, aluminum and lead metallurgies, in Portugal. The study reports the emission factors and total emission amounts of PCDD/Fs, dioxin-like PCBs and hexachlorobenzene (HCB). The congener patterns were characterized and are discussed. The results showed that the total amount of PCDFs is higher than PCDDs in flue gas of each industrial unit. The toxic equivalent emission factors of pollutants emitted are 3098-3338 ngI-TEQt(-1) for PCDD/Fs and 597-659 ng I-TEQt(-1) for dioxin-like PCBs in siderurgies production (total estimated emission amounts released to atmosphere of 3.9-4.5 g I-TEQyr(-1)), 50-152 ng I-TEQt(-1) for PCDD/Fs and 24-121 ng I-TEQt(-1) for dioxin-like PCBs in ferrous foundries production (total estimated emission amounts released to atmosphere of 0.0010-0.0016 g I-TEQyr(-1)) and 5.8-5715 ng I-TEQt(-1) for PCDD/Fs and 0.49-259 ng I-TEQt(-1) for dioxin-like PCBs in non-ferrous foundries production (total estimated emission amounts released to atmosphere of 0.00014-0.12 g I-TEQyr(-1)). The HCB emission from siderurgies production is 0.94-3.2 mg t(-1) (total estimated emission amounts released 0.94-3.8 g yr(-1)), being much smaller, residual, in the emissions of the other types of plants (0.0012-0.026 mg t(-1) production and total estimated emission amounts released to atmosphere of 0.013-1.7 mg yr(-1)). Copyright © 2012 Elsevier Ltd. All rights reserved.

Secondary metabolite concentrations and terpene emissions of Scots pine xylem after long-term forest fertilization.

PubMed

Turtola, S; Manninen, A M; Holopainen, J K; Levula, T; Raitio, H; Kainulainen, P

2002-01-01

Secondary compounds are known to be associated with the resistance of conifer xylem against insects and fungi. The effects of long-term forest fertilization with nitrogen (N) or with N, calcium (Ca), and phosphorus (P) on secondary compounds in the xylem of 50-yr-old Scots pine (Pinus sylvestris L.) trees were examined. Xylem samples were collected from trees growing in three locations in southern Finland: Vilppula, Padasjoki, and Punkaharju. Forests were fertilized every fifth (Vilppula and Padasjoki) or tenth (Punkaharju) year since the 1950s. We compared concentrations of individual and total monoterpenes and resin acids in the heartwood and sapwood of Scots pine. Terpene emissions were analyzed from the sapwood and total phenolics from the heartwood. Fertilization did not have any significant effect on the concentrations and emissions of xylem monoterpenes. Concentrations of several individual terpenes in sapwood were positively correlated with the corresponding terpene emission. The concentrations of individual resin acids (i.e., abietic and dehydroabietic) decreased significantly in Punkaharju, but increased in the sapwood of N-fertilized trees compared with control ones at Padasjoki and Vilppula. The concentrations of resin acids in the heartwood were not significantly affected by fertilization. Both fertilization treatments decreased the total phenolic concentrations in the heartwood of trees growing in Padasjoki. There was a significant positive correlation between the total phenolics and total resin acid concentration. Overall, resin acids and phenolics seemed be more responsive than monoterpenes to N treatment. These results suggest that forest fertilization might cause slight changes in secondary compound concentrations of xylem, and thus might have significance in the decay resistance of wood.

Primary and secondary sources of formaldehyde in urban atmospheres: Houston Texas region

NASA Astrophysics Data System (ADS)

Parrish, D. D.; Ryerson, T. B.; Mellqvist, J.; Johansson, J.; Fried, A.; Richter, D.; Walega, J. G.; Washenfelder, R. A.; de Gouw, J. A.; Peischl, J.; Aikin, K. C.; McKeen, S. A.; Frost, G. J.; Fehsenfeld, F. C.; Herndon, S. C.

2011-12-01

We evaluate the rates of secondary production and primary emission of formaldehyde (CH2O) from petrochemical industrial facilities and on-road vehicles in the Houston Texas region. This evaluation is based upon ambient measurements collected during field studies in 2000, 2006 and 2009. The predominant CH2O source (92 ± 4% of total) is secondary production formed during the atmospheric oxidation of highly reactive volatile organic compounds (HRVOCs) emitted from the petrochemical facilities. Smaller contributions are primary emissions from these facilities (4 ± 2%), and secondary production (~3%) and primary emissions (~1%) from vehicles. The primary emissions from both sectors are well quantified by current emission inventories. Since secondary production dominates, control efforts directed at primary CH2O emissions cannot address the large majority of CH2O sources in the Houston area, although there may still be a role for such efforts. Ongoing efforts to control alkene emissions from the petrochemical facilities, as well as volatile organic compound emissions from the motor vehicle fleet, will effectively reduce the CH2O concentrations in the Houston region. We have not addressed other emission sectors, such as off-road mobile sources or secondary formation from biogenic hydrocarbons. Previous analyses based on correlations between ambient concentrations of CH2O and various marker species have suggested much larger primary emissions of CH2O, but those results neglect confounding effects of dilution and loss processes, and do not demonstrate the causes of the observed correlations. Similar problems must be suspected in any source apportionment analysis of secondary species based upon correlations of ambient concentrations of pollutants.

Primary and secondary sources of formaldehyde in urban atmospheres: Houston Texas region

NASA Astrophysics Data System (ADS)

Parrish, D. D.; Ryerson, T. B.; Mellqvist, J.; Johansson, J.; Fried, A.; Richter, D.; Walega, J. G.; Washenfelder, R. A.; de Gouw, J. A.; Peischl, J.; Aikin, K. C.; McKeen, S. A.; Frost, G. J.; Fehsenfeld, F. C.; Herndon, S. C.

2012-04-01

We evaluate the rates of secondary production and primary emission of formaldehyde (CH2O) from petrochemical industrial facilities and on-road vehicles in the Houston Texas region. This evaluation is based upon ambient measurements collected during field studies in 2000, 2006 and 2009. The predominant CH2O source (92 ± 4% of total) is secondary production formed during the atmospheric oxidation of highly reactive volatile organic compounds (HRVOCs) emitted from the petrochemical facilities. Smaller contributions are primary emissions from these facilities (4 ± 2%), and secondary production (~3%) and primary emissions (~1%) from vehicles. The primary emissions from both sectors are well quantified by current emission inventories. Since secondary production dominates, control efforts directed at primary CH2O emissions cannot address the large majority of CH2O sources in the Houston area, although there may still be a role for such efforts. Ongoing efforts to control alkene emissions from the petrochemical facilities, as well as volatile organic compound emissions from the motor vehicle fleet, will effectively reduce the CH2O concentrations in the Houston region. We do not address other emission sectors, such as off-road mobile sources or secondary formation from biogenic hydrocarbons. Previous analyses based on correlations between ambient concentrations of CH2O and various marker species have suggested much larger primary emissions of CH2O, but those results neglect confounding effects of dilution and loss processes, and do not demonstrate the causes of the observed correlations. Similar problems must be suspected in any source apportionment analysis of secondary species based upon correlations of ambient concentrations of pollutants.

Mercury enrichment and its effects on atmospheric emissions in cement plants of China

NASA Astrophysics Data System (ADS)

Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Wu, Qingru; Hao, Jiming

2014-08-01

The cement industry is one of the most significant anthropogenic sources of atmospheric mercury emissions worldwide. In this study of three typical Chinese cement plants, mercury in kiln flue gas was sampled using the Ontario Hydro Method (OHM), and solid samples were analyzed. Particulate matter recycling, preheating of raw materials, and the use of coal and flue gas desulfurization derived gypsum contributed to emissions of Hg in the air and to accumulation in cement. Over 90% of the mercury input was emitted into the atmosphere. Mercury emission factors were 0.044-0.072 g/t clinker for the test plants. The major species emitted into the atmosphere from cement plants is oxidized mercury, accounting for 61%-91% of the total mercury in flue gas. The results of this study help improve the accuracy of the mercury emission inventory in China and provide useful information for developing mercury controls.

Long-term measurement of terpenoid flux above a Larix kaempferi forest using a relaxed eddy accumulation method

NASA Astrophysics Data System (ADS)

Mochizuki, Tomoki; Tani, Akira; Takahashi, Yoshiyuki; Saigusa, Nobuko; Ueyama, Masahito

2014-02-01

Terpenoids emitted from forests contribute to the formation of secondary organic aerosols and affect the carbon budgets of forest ecosystems. To investigate seasonal variation in terpenoid flux involved in the aerosol formation and carbon budget, we measured the terpenoid flux of a Larix kaempferi forest between May 2011 and May 2012 by using a relaxed eddy accumulation method. Isoprene was emitted from a fern plant species Dryopteris crassirhizoma on the forest floor and monoterpenes from the L. kaempferi. α-Pinene was the dominant compound, but seasonal variation of the monoterpene composition was observed. High isoprene and monoterpene fluxes were observed in July and August. The total monoterpene flux was dependent on temperature, but several unusual high positive fluxes were observed after rain fall events. We found a good correlation between total monoterpene flux and volumetric soil water content (r = 0.88), and used this correlation to estimate monoterpene flux after rain events and calculate annual terpenoid emissions. Annual carbon emission in the form of total monoterpenes plus isoprene was determined to be 0.93% of the net ecosystem exchange. If we do not consider the effect of rain fall, carbon emissions may be underestimated by about 50%. Our results suggest that moisture conditions in the forest soil is a key factor controlling the monoterpene emissions from the forest ecosystem.

Variation of ambient non-methane hydrocarbons in Beijing city in summer 2008

NASA Astrophysics Data System (ADS)

Wang, B.; Shao, M.; Lu, S. H.; Yuan, B.; Zhao, Y.; Wang, M.; Zhang, S. Q.; Wu, D.

2010-02-01

In conjunction with hosting the 2008 Beijing Olympics, the municipal government implemented a series of stringent air quality control measures. To assess the impacts on variation of ambient non-methane hydrocarbons (NMHCs), the whole air was sampled by canisters at one urban site and two suburban sites in Beijing, and 55 NMHC species were quantified by gas chromatography equipped with a quadrupole mass spectrometer and a flame ionization detector (GC/MSD/FID) as parts of the field Campaign for the Beijing Olympic Games Air Quality program (CareBeijing). According to the control measures, the data were presented according to four periods: 18-30 June, 8-19 July, 15-24 August (during the Olympic Games), and 6-15 September (during the Paralympic Games). Compared with the levels in June, the mixing ratios of NMHCs obtained in the Olympic and Paralympic Games periods were reduced by 35% and 25%, respectively. Source contributions were calculated using a chemical mass balance model (CMB 8.2). After implementing the control measures, emissions from target sources were obviously reduced, and reductions in vehicle exhaust could explain 48-82% of the reductions of ambient NMHCs. Reductions in emissions from gasoline evaporation, paint and solvent use, and the chemical industry contributed 9-40%, 3-24%, and 1-5%, respectively, to reductions of ambient NMHCs. Sources of liquefied petroleum gas (LPG) and biogenic emissions were not controlled, and contributions from these sources from July to September were stable or even higher than in June. Ozone formation potentials (OFPs) were calculated for the measured NMHCs. The total OFPs during the Olympic and Paralympic Games were reduced by 48% and 32%, respectively, compared with values in June. Reductions in the OFPs of alkenes and aromatics explained 77-92% of total OFP reductions. The alkenes and aromatics were mainly from vehicle exhausts, and reductions of vehicle exhaust gases explained 67-87% of reductions in alkenes and 38-80% of reductions in aromatics. These findings demonstrate the effectiveness of the air quality control measures enacted for the 2008 Olympics and indicate that controlling vehicular emissions could be the most important measure to improve air quality in Beijing.

Variation of ambient non-methane hydrocarbons in Beijing city in summer 2008

NASA Astrophysics Data System (ADS)

Wang, B.; Shao, M.; Lu, S. H.; Yuan, B.; Zhao, Y.; Wang, M.; Zhang, S. Q.; Wu, D.

2010-07-01

In conjunction with hosting the 2008 Beijing Olympics, the municipal government implemented a series of stringent air quality control measures. To assess the impacts on variation of ambient non-methane hydrocarbons (NMHCs), the whole air was sampled by canisters at one urban site and two suburban sites in Beijing, and 55 NMHC species were quantified by gas chromatography equipped with a quadrupole mass spectrometer and a flame ionization detector (GC/MSD/FID) as parts of the field Campaign for the Beijing Olympic Games Air Quality program (CareBeijing). According to the control measures, the data were presented according to four periods: 18-30 June, 8-19 July, 15-24 August (during the Olympic Games), and 6-15 September (during the Paralympic Games). Compared with the levels in June, the mixing ratios of NMHCs obtained in the Olympic and Paralympic Games periods were reduced by 35% and 25%, respectively. Source contributions were calculated using a chemical mass balance model (CMB 8.2). After implementing the control measures, emissions from target sources were obviously reduced, and reductions in vehicle exhaust could explain 48-82% of the reductions of ambient NMHCs. Reductions in emissions from gasoline evaporation, paint and solvent use, and the chemical industry contributed 9-40%, 3-24%, and 1-5%, respectively, to reductions of ambient NMHCs. Sources of liquefied petroleum gas (LPG) and biogenic emissions were not controlled, and contributions from these sources from July to September were stable or even higher than in June. Ozone formation potentials (OFPs) were calculated for the measured NMHCs. The total OFPs during the Olympic and Paralympic Games were reduced by 48% and 32%, respectively, compared with values in June. Reductions in the OFPs of alkenes and aromatics explained 77-92% of total OFP reductions. The alkenes and aromatics were mainly from vehicle exhausts, and reductions of vehicle exhaust gases explained 67-87% of reductions in alkenes and 38-80% of reductions in aromatics. These findings demonstrate the effectiveness of the air quality control measures enacted for the 2008 Olympics and indicate that controlling vehicular emissions could be the most important measure to improve air quality in Beijing.

Life-cycle-assessment of the historical development of air pollution control and energy recovery in waste incineration.

PubMed

Damgaard, Anders; Riber, Christian; Fruergaard, Thilde; Hulgaard, Tore; Christensen, Thomas H

2010-07-01

Incineration of municipal solid waste is a debated waste management technology. In some countries it is the main waste management option whereas in other countries it has been disregarded. The main discussion point on waste incineration is the release of air emissions from the combustion of the waste, but also the energy recovery efficiency has a large importance. The historical development of air pollution control in waste incineration was studied through life-cycle-assessment modelling of eight different air pollution control technologies. The results showed a drastic reduction in the release of air emissions and consequently a significant reduction in the potential environmental impacts of waste incineration. Improvements of a factor 0.85-174 were obtained in the different impact potentials as technology developed from no emission control at all, to the best available emission control technologies of today (2010). The importance of efficient energy recovery was studied through seven different combinations of heat and electricity recovery, which were modelled to substitute energy produced from either coal or natural gas. The best air pollution control technology was used at the incinerator. It was found that when substituting coal based energy production total net savings were obtained in both the standard and toxic impact categories. However, if the substituted energy production was based on natural gas, only the most efficient recovery options yielded net savings with respect to the standard impacts. With regards to the toxic impact categories, emissions from the waste incineration process were always larger than those from the avoided energy production based on natural gas. The results shows that the potential environmental impacts from air emissions have decreased drastically during the last 35 years and that these impacts can be partly or fully offset by recovering energy which otherwise should have been produced from fossil fuels like coal or natural gas. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

EVALUATION OF MERCURY SPECIATION AT POWER PLANTS USING SCR AND SNCR NOX CONTROL TECHNOLOGIES

EPA Science Inventory

The paper describes the impact that selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), and flue gas-conditioning systems have on total mercury emissions and on the speciation of mercury. If SCR and/or SNCR systems enhance mercury conversion/capture, the...

40 CFR 62.7853 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mexico Total Reduced Sulfur Emissions from Kraft Pulp Mills § 62.7853 Identification of plan—negative declaration. (a) Letter from the New Mexico Environmental Improvement Division dated November 5, 1979... Bernalillo County on lands under the jurisdiction of the Albuquerque/Bernalillo County Air Quality Control...

40 CFR 62.7853 - Identification of plan-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Mexico Total Reduced Sulfur Emissions from Kraft Pulp Mills § 62.7853 Identification of plan—negative declaration. (a) Letter from the New Mexico Environmental Improvement Division dated November 5, 1979... Bernalillo County on lands under the jurisdiction of the Albuquerque/Bernalillo County Air Quality Control...

EVALUATION OF MERCURY SPECIATION AT POWER PLANTS USING SCR AND SNCR CONTROL TECHNOLOGIES

EPA Science Inventory

The paper describes the impact that selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), and flue gas-conditioning systems have on total mercury emissions and on the speciation of mercury. If SCR and/or SNCR systems enhance mercury conversion/capture, the...

40 CFR 62.11610 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Reduced Sulfur Emissions from Existing Kraft Pulp Mills § 62.11610 Identification of plan. (a) Title of... Department of Virginia Department of Air Pollution Control, on May 15, 1990. (c) Identification of sources... process (added), Straight kraft recovery furnace (revised), Total reduced sulfur (revised)), 5-40-1690, 5...

Improving air pollution control policy in China--A perspective based on cost-benefit analysis.

PubMed

Gao, Jinglei; Yuan, Zengwei; Liu, Xuewei; Xia, Xiaoming; Huang, Xianjin; Dong, Zhanfeng

2016-02-01

To mitigate serious air pollution, the State Council of China promulgated the Air Pollution Prevention and Control Action Plan in 2013. To verify the feasibility and validity of industrial energy-saving and emission-reduction policies in the action plan, we conducted a cost-benefit analysis of implementing these policies in 31 provinces for the period of 2013 to 2017. We also completed a scenario analysis in this study to assess the cost-effectiveness of different measures within the energy-saving and the emission-reduction policies individually. The data were derived from field surveys, statistical yearbooks, government documents, and published literatures. The results show that total cost and total benefit are 118.39 and 748.15 billion Yuan, respectively, and the estimated benefit-cost ratio is 6.32 in the S3 scenario. For all the scenarios, these policies are cost-effective and the eastern region has higher satisfactory values. Furthermore, the end-of-pipe scenario has greater emission reduction potential than energy-saving scenario. We also found that gross domestic product and population are significantly correlated with the benefit-cost ratio value through the regression analysis of selected possible influencing factors. The sensitivity analysis demonstrates that benefit-cost ratio value is more sensitive to unit emission-reduction cost, unit subsidy, growth rate of gross domestic product, and discount rate among all the parameters. Compared with other provinces, the benefit-cost ratios of Beijing and Tianjin are more sensitive to changes of unit subsidy than unit emission-reduction cost. These findings may have significant implications for improving China's air pollution prevention policy. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantum fluctuations of radiation in a ring Nd : YAG chip laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lariontsev, E G; Firsov, V V

2015-07-31

We report theoretical and experimental investigation of intensity fluctuations in a travelling-wave ring Nd : YAG chip laser, caused by the noise of spontaneous emission. In accordance with theory and experiment, quantum intensity fluctuations in the laser under study decrease dramatically with increasing pump over the threshold. As a result of the research performed, the factor β is found, which determines the ratio of the rate of spontaneous emission into the generated mode to the total rate of spontaneous emission into all modes. The effect of the relaxation rate from the lower laser level on quantum fluctuations of the radiationmore » intensity is found. (control of radiation parameters)« less

Spatial-temporal Variations and Source Apportionment of typical Heavy Metals in Beijing-Tianjin-Hebei (BTH) region of China Based on Localized Air Pollutants Emission Inventory and WRF-CMAQ modelling

NASA Astrophysics Data System (ADS)

Tian, H.; Liu, S.; Zhu, C.; Liu, H.; Wu, B.

2017-12-01

Abstract: Anthropogenic atmospheric emissions of air pollutants have caused worldwide concerns due to their adverse effects on human health and the ecosystem. By determining the best available emission factors for varied source categories, we established the comprehensive atmospheric emission inventories of hazardous air pollutants including 12 typical toxic heavy metals (Hg, As, Se, Pb, Cd, Cr, Ni, Sb, Mn, Co, Cu, and Zn) from primary anthropogenic activities in Beijing-Tianjin-Hebei (BTH) region of China for the period of 2012 for the first time. The annual emissions of these pollutants were allocated at a high spatial resolution of 9km × 9km grid with ArcGIS methodology and surrogate indexes, such as regional population and gross domestic product (GDP). Notably, the total heavy metal emissions from this region represented about 10.9% of the Chinese national total emissions. The areas with high emissions of heavy metals were mainly concentrated in Tangshan, Shijiazhuang, Handan and Tianjin. Further, WRF-CMAQ modeling system were applied to simulate the regional concentration of heavy metals to explore their spatial-temporal variations, and the source apportionment of these heavy metals in BTH region was performed using the Brute-Force method. Finally, integrated countermeasures were proposed to minimize the final air pollutants discharge on account of the current and future demand of energy-saving and pollution reduction in China. Keywords: heavy metals; particulate matter; emission inventory; CMAQ model; source apportionment Acknowledgment. This work was funded by the National Natural Science Foundation of China (21377012 and 21177012) and the Trail Special Program of Research on the Cause and Control Technology of Air Pollution under the National Key Research and Development Plan of China (2016YFC0201501).

Nitrous oxide emissions and dissolved oxygen profiling in a full-scale nitrifying activated sludge treatment plant.

PubMed

Aboobakar, Amina; Cartmell, Elise; Stephenson, Tom; Jones, Mark; Vale, Peter; Dotro, Gabriela

2013-02-01

This paper reports findings from online, continuous monitoring of dissolved and gaseous nitrous oxide (N₂O), combined with dissolved oxygen (DO) and ammonia loading, in a full-scale nitrifying activated sludge plant. The study was conducted over eight weeks, at a 210,000 population equivalent sewage treatment works in the UK. Results showed diurnal variability in the gaseous and dissolved N₂O emissions, with hourly averages ranging from 0 to 0.00009 kgN₂O-N/h for dissolved and 0.00077-0.0027 kgN₂O-N/h for gaseous nitrous oxide emissions respectively, per ammonia loading, depending on the time of day. Similarly, the spatial variability was high, with the highest emissions recorded immediately after the anoxic zone and in the final pass of the aeration lane, where ammonia concentrations were typically below 0.5 mg/L. Emissions were shown to be negatively correlated to dissolved oxygen, which fluctuated between 0.5 and 2.5 mgO₂/L, at the control set point of 1.5 mgO₂/L. The resulting dynamic DO conditions are known to favour N₂O production, both by autotrophic and heterotrophic processes in mixed cultures. Average mass emissions from the lane were greater in the gaseous (0.036% of the influent total nitrogen) than in the dissolved (0.01% of the influent total nitrogen) phase, and followed the same diurnal and spatial patterns. Nitrous oxide emissions corresponded to over 34,000 carbon dioxide equivalents/year, adding 13% to the carbon footprint associated with the energy requirements of the monitored lane. A clearer understanding of emissions obtained from real-time data can help towards finding the right balance between improving operational efficiency and saving energy, without increasing N₂O emissions. Copyright © 2012 Elsevier Ltd. All rights reserved.

Temporal and spatial variation characteristics of atmospheric emissions of Cd, Cr, and Pb from coal in China

NASA Astrophysics Data System (ADS)

Tian, Hezhong; Cheng, Ke; Wang, Yan; Zhao, Dan; Lu, Long; Jia, Wenxiao; Hao, Jiming

2012-04-01

Multiple-year inventory of atmospheric emissions of cadmium (Cd), chromium (Cr), and lead (Pb) from coal burning in China have been established for the period 1980-2008 by using best available emission factors and annual activity data which are specified by different sub-categories of combustion facilities, coal types, and air pollution control devices. Our results show that the total emissions of Cd, Cr, and Pb have rapidly increased from 31.14 t, 1019.07 t, and 2671.73 t in 1980 to 261.52 t, 8593.35 t, and 12 561.77 t in 2008, respectively. The industrial sector ranks as the leading source, contributing ˜88.3%, ˜86.7%, and ˜81.8% of the total Cd, Cr, and Pb emissions, respectively. Remarkably uneven spatial allocation features are observed. The emissions are primarily concentrated in the provinces of the northern and eastern region of China owing to the dramatic difference in coal use by the industrial and power sectors. Monthly temporal emission profiles for different sectors are established by using indexes such as monthly thermal electricity generation, monthly gross industrial output values and monthly average ambient temperature. For the power plants, there are two peaks during cold and hot season while for the industrial sector, emissions are most substantial in the summer and autumn season. Further, uncertainties in the bottom-up inventories are quantified by Monte Carlo simulation, and the overall uncertainties are demonstrated as -16% to 45% for Cd, -13% to 20% for Cr, and -21% to 48% for Pb, respectively. To better understand the emissions of these metals and to adopt effective measures to prevent poisoning, more specific data collection and analysis are necessary.

European type-approval test procedure for evaporative emissions from passenger cars against real-world mobility data from two Italian provinces.

PubMed

Martini, Giorgio; Paffumi, Elena; De Gennaro, Michele; Mellios, Giorgos

2014-07-15

This paper presents an evaluation of the European type-approval test procedure for evaporative emissions from passenger cars based on real-world mobility data. The study relies on two large databases of driving patterns from conventional fuel vehicles collected by means of on-board GPS systems in the Italian provinces of Modena and Firenze. Approximately 28,000 vehicles were monitored, corresponding to approximately 36 million kilometres over a period of one month. The driving pattern of each vehicle was processed to derive the relation between trip length and parking duration, and the rate of occurrence of parking events against multiple evaporative cycles, defined on the basis of the type-approval test procedure as 12-hour diurnal time windows. These results are used as input for an emission simulation model, which calculates the total evaporative emissions given the characteristics of the evaporative emission control system of the vehicle and the ambient temperature conditions. The results suggest that the evaporative emission control system, fitted to the vehicles from Euro 3 step and optimised for the current type-approval test procedure, could not efficiently work under real-world conditions, resulting in evaporative emissions well above the type-approval limit, especially for small size vehicles and warm climate conditions. This calls for a revision of the type-approval test procedure in order to address real-world evaporative emissions. Copyright © 2014. Published by Elsevier B.V.

Control strategies of atmospheric mercury emissions from coal-fired power plants in China.

PubMed

Tian, Hezhong; Wang, Yan; Cheng, Ke; Qu, Yiping; Hao, Jiming; Xue, Zhigang; Chai, Fahe

2012-05-01

Atmospheric mercury (Hg) emission from coal is one of the primary sources of anthropogenic discharge and pollution. China is one of the few countries in the world whose coal consumption constitutes about 70% of total primary energy, and over half of coals are burned directly for electricity generation. Atmospheric emissions of Hg and its speciation from coal-fired power plants are of great concern owing to their negative impacts on regional human health and ecosystem risks, as well as long-distance transport. In this paper, recent trends of atmospheric Hg emissions and its species split from coal-fired power plants in China during the period of 2000-2007 are evaluated, by integrating each plant's coal consumption and emission factors, which are classified by different subcategories of boilers, particulate matter (PM) and sulfur dioxide (SO2) control devices. Our results show that the total Hg emissions from coal-fired power plants have begun to decrease from the peak value of 139.19 t in 2005 to 134.55 t in 2007, though coal consumption growing steadily from 1213.8 to 1532.4 Mt, which can be mainly attributed to the co-benefit Hg reduction by electrostatic precipitators/fabric filters (ESPs/FFs) and wet flue gas desulfurization (WFGD), especially the sharp growth in installation of WFGD both in the new and existing power plants since 2005. In the coming 12th five-year-plan, more and more plants will be mandated to install De-NO(x) (nitrogen oxides) systems (mainly selective catalytic reduction [SCR] and selective noncatalytic reduction [SNCR]) for minimizing NO(x) emission, thus the specific Hg emission rate per ton of coal will decline further owing to the much higher co-benefit removal efficiency by the combination of SCR + ESPs/FFs + WFGD systems. Consequently, SCR + ESPs/FFs + WFGD configuration will be the main path to abate Hg discharge from coal-fired power plants in China in the near future. However advanced specific Hg removal technologies are necessary for further reduction of elemental Hg discharge in the long-term.

Modeling spatial patterns of link-based PM2.5 emissions and subsequent human exposure in a large canadian metropolitan area

NASA Astrophysics Data System (ADS)

Requia, Weeberb J.; Dalumpines, Ron; Adams, Matthew D.; Arain, Altaf; Ferguson, Mark; Koutrakis, Petros

2017-06-01

Understanding the relationship between mobile source emissions and subsequent human exposure is crucial for emissions control. Determining this relationship over space is fundamental to improve the accuracy and precision of public policies. In this study, we evaluated the spatial patterns of link-based PM2.5 emissions and subsequent human exposure in a large Canadian metropolitan area - the Greater Toronto and Hamilton Area (GTHA). This study was performed in three stages. First, we estimated vehicle emissions using transportation models and emission simulators. Then we evaluated human exposure to PM2.5 emissions using the Intake fraction (iF) approach. Finally, we applied geostatistical methods to assess spatial patterns of vehicle emissions and subsequent human exposure based on three prospective goals: i) classification of emissions (Global Moran's I test), ii) level of emission exposure (Getis-Ord General G test), and; iii) location of emissions (Anselin Local Moran's I). Our results showed that passenger vehicles accounted for the highest total amount of PM2.5 emissions, representing 57% emissions from all vehicles. Examining only the emissions from passenger vehicles, on average, each person in the GTHA inhales 2.58 × 10-3 ppm per day. Accounting the emissions from buses and trucks, on average each person inhales 0.12 × 10-3 and 1.91 × 10-3 ppm per day, respectively. For both PM2.5 emissions and human exposure using iF approach, our analysis showed Moran's Index greater than 0 for all vehicle categories, suggesting the presence of significant clusters (p-value <0.01) in the region. Our study indicates that air pollution control policy must be developed for the whole region, because of the spatial distribution of housing and businesses centers and inter-connectivity of transportation networks across the region, where a policy cannot simply be based on a municipal or other boundaries.

Pay attention to non-wastewater emission pathways of pharmaceuticals into environments.

PubMed

Bu, Qingwei; Shi, Xiao; Yu, Gang; Huang, Jun; Wang, Bin; Wang, Jianbing

2016-12-01

Pharmaceuticals have been widely detected in the aquatic environment and demonstrated to be potential risks to humans and the environment. Understanding emission pathways of pharmaceuticals is essential to the control of pharmaceutical contamination for environmental management. The present study is aimed at testing the hypothesis that non-wastewater pathway is also significant to the emission of pharmaceuticals into the environment. To this end, we compared the actual production with the amount of 12 antibiotics obtained by back calculation from sewage concentrations in Beijing, Guangzhou and Chongqing. The results showed that for over a half of investigated antibiotics, the emission through non-wastewater pathways accounted for approximately 30-80% of the total emission, varying with individual antibiotics. It was revealed that non-wastewater emission pathways could be of significance for pharmaceuticals emitted into the environment, of which disposed by household waste could be among the most important non-wastewater pathways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Estimating PM2.5-associated mortality increase in California due to the Volkswagen emission control defeat device

NASA Astrophysics Data System (ADS)

Wang, Tianyang; Jerrett, Michael; Sinsheimer, Peter; Zhu, Yifang

2016-11-01

The Volkswagen Group of America (VW) was found by the US Environmental Protection Agency (EPA) and the California Air Resources Board (CARB) to have installed "defeat devices" and emit more oxides of nitrogen (NOx) than permitted under current EPA standards. In this paper, we quantify the hidden NOx emissions from this so-called VW scandal and the resulting public health impacts in California. The NOx emissions are calculated based on VW road test data and the CARB Emission Factors (EMFAC) model. Cumulative hidden NOx emissions from 2009 to 2015 were estimated to be over 3500 tons. Adult mortality changes were estimated based on ambient fine particulate matter (PM2.5) change due to secondary nitrate formation and the related concentration-response functions. We estimated that hidden NOx emissions from 2009 to 2015 have resulted in a total of 12 PM2.5-associated adult mortality increases in California. Most of the mortality increase happened in metropolitan areas, due to their high population and vehicle density.

Emissions of methane in Europe inferred by total column measurements

NASA Astrophysics Data System (ADS)

Wunch, D.; Deutscher, N. M.; Hase, F.; Notholt, J.; Sussmann, R.; Toon, G. C.; Warneke, T.

2017-12-01

Atmospheric total column measurements have been used to infer emissions of methane in urban centres around the world. These measurements have been shown to be useful for verifying city-scale bottom-up inventories, and they can provide both timely and sub-annual emission information. We will present our analysis of atmospheric total column measurements of methane and carbon monoxide to infer annual and seasonal regional emissions of methane within Europe using five long-running atmospheric observatories. These observatories are part of the Total Carbon Column Observing Network, part of a global network that has been carefully designed to measure these gases on a consistent scale. Our inferred emissions will then be used to evaluate gridded emissions inventories in the region.

Modelling the spatial distribution of SO2 and NOx emissions in Ireland.

PubMed

de Kluizenaar, Y; Aherne, J; Farrell, E P

2001-01-01

The spatial distributions of sulphur dioxide (SO2) and nitrogen oxides (NOx) emissions are essential inputs to models of atmospheric transport and deposition. Information of this type is required for international negotiations on emission reduction through the critical load approach. High-resolution emission maps for the Republic of Ireland have been created using emission totals and a geographical information system, supported by surrogate statistics and landcover information. Data have been subsequently allocated to the EMEP 50 x 50-km grid, used in long-range transport models for the investigation of transboundary air pollution. Approximately two-thirds of SO2 emissions in Ireland emanate from two grid-squares. Over 50% of total SO2 emissions originate from one grid-square in the west of Ireland, where the largest point sources of SO2 are located. Approximately 15% of the total SO2 emissions originate from the grid-square containing Dublin. SO2 emission densities for the remaining areas are very low, < 1 t km-2 year-1 for most grid-squares. NOx emissions show a very similar distribution pattern. However, NOx emissions are more evenly spread over the country, as about 40% of total NOx emissions originate from road transport.

The Role of Industrial Parks in Mitigating Greenhouse Gas Emissions from China.

PubMed

Guo, Yang; Tian, Jinping; Zang, Na; Gao, Yang; Chen, Lujun

2018-06-14

This study uncovered the direct and indirect energy-related GHG emissions of 213 Chinese national-level industrial parks, providing 11% of China's GDP, from a life-cycle perspective. Direct emissions are sourced from fuel combustion, and indirect emissions are embodied in energy production. The results indicated that in 2015, the direct and indirect GHG emissions of the parks were 1042 and 181 million tonne CO2 eq., respectively, totally accounting for 11% of national GHG emissions. The total energy consumption of the parks accounted for 10% of national energy consumption. Coal constituted 74% of total energy consumption in these parks. Baseline and low-carbon scenarios are established for 2030, and five GHG mitigation measures targeting energy consumption are modeled. The GHG mitigation potential for these parks in 2030 is quantified as 116 million tonne, equivalent to 9.5% of the parks' total emission in 2015. The measures that increase the share of natural gas consumption, reduce the GHG emission factor of electricity grid, and improve the average efficiency of industrial coal-fired boilers, will totally contribute 94% and 98% in direct and indirect GHG emissions reductions, respectively. These findings will provide a solid foundation for the low-carbon development of Chinese industrial parks.

The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China.

PubMed

Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

2016-06-24

This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO₂e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO₂e is 8215.31 tons. Based on the evaluation results, the CO₂e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO₂e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO₂e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO₂ in each phase, which accounts for more than 98% of total emissions. N₂O and CH₄ emissions are relatively insignificant.

Observed decrease in atmospheric mercury explained by global decline in anthropogenic emissions

PubMed Central

Zhang, Yanxu; Jacob, Daniel J.; Horowitz, Hannah M.; Chen, Long; Amos, Helen M.; Krabbenhoft, David P.; Slemr, Franz; St. Louis, Vincent L.; Sunderland, Elsie M.

2016-01-01

Observations of elemental mercury (Hg0) at sites in North America and Europe show large decreases (∼1–2% y−1) from 1990 to present. Observations in background northern hemisphere air, including Mauna Loa Observatory (Hawaii) and CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) aircraft flights, show weaker decreases (<1% y−1). These decreases are inconsistent with current global emission inventories indicating flat or increasing emissions over that period. However, the inventories have three major flaws: (i) they do not account for the decline in atmospheric release of Hg from commercial products; (ii) they are biased in their estimate of artisanal and small-scale gold mining emissions; and (iii) they do not properly account for the change in Hg0/HgII speciation of emissions from coal-fired utilities after implementation of emission controls targeted at SO2 and NOx. We construct an improved global emission inventory for the period 1990 to 2010 accounting for the above factors and find a 20% decrease in total Hg emissions and a 30% decrease in anthropogenic Hg0 emissions, with much larger decreases in North America and Europe offsetting the effect of increasing emissions in Asia. Implementation of our inventory in a global 3D atmospheric Hg simulation [GEOS-Chem (Goddard Earth Observing System-Chemistry)] coupled to land and ocean reservoirs reproduces the observed large-scale trends in atmospheric Hg0 concentrations and in HgII wet deposition. The large trends observed in North America and Europe reflect the phase-out of Hg from commercial products as well as the cobenefit from SO2 and NOx emission controls on coal-fired utilities. PMID:26729866

Observed decrease in atmospheric mercury explained by global decline in anthropogenic emissions.

PubMed

Zhang, Yanxu; Jacob, Daniel J; Horowitz, Hannah M; Chen, Long; Amos, Helen M; Krabbenhoft, David P; Slemr, Franz; St Louis, Vincent L; Sunderland, Elsie M

2016-01-19

Observations of elemental mercury (Hg(0)) at sites in North America and Europe show large decreases (∼ 1-2% y(-1)) from 1990 to present. Observations in background northern hemisphere air, including Mauna Loa Observatory (Hawaii) and CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) aircraft flights, show weaker decreases (<1% y(-1)). These decreases are inconsistent with current global emission inventories indicating flat or increasing emissions over that period. However, the inventories have three major flaws: (i) they do not account for the decline in atmospheric release of Hg from commercial products; (ii) they are biased in their estimate of artisanal and small-scale gold mining emissions; and (iii) they do not properly account for the change in Hg(0)/Hg(II) speciation of emissions from coal-fired utilities after implementation of emission controls targeted at SO2 and NOx. We construct an improved global emission inventory for the period 1990 to 2010 accounting for the above factors and find a 20% decrease in total Hg emissions and a 30% decrease in anthropogenic Hg(0) emissions, with much larger decreases in North America and Europe offsetting the effect of increasing emissions in Asia. Implementation of our inventory in a global 3D atmospheric Hg simulation [GEOS-Chem (Goddard Earth Observing System-Chemistry)] coupled to land and ocean reservoirs reproduces the observed large-scale trends in atmospheric Hg(0) concentrations and in Hg(II) wet deposition. The large trends observed in North America and Europe reflect the phase-out of Hg from commercial products as well as the cobenefit from SO2 and NOx emission controls on coal-fired utilities.

Recent trends in global emissions of hydrochlorofluorocarbons and hydrofluorocarbons: reflecting on the 2007 adjustments to the Montreal Protocol.

PubMed

Montzka, S A; McFarland, M; Andersen, S O; Miller, B R; Fahey, D W; Hall, B D; Hu, L; Siso, C; Elkins, J W

2015-05-14

Global-scale atmospheric measurements are used to investigate the effectiveness of recent adjustments to production and consumption controls on hydrochlorofluorocarbons (HCFCs) under the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) and to assess recent projections of large increases in hydrofluorocarbon (HFC) production and emission. The results show that aggregate global HCFC emissions did not increase appreciably during 2007-2012 and suggest that the 2007 Adjustments to the Montreal Protocol played a role in limiting HCFC emissions well in advance of the 2013 cap on global production. HCFC emissions varied between 27 and 29 kt CFC-11-equivalent (eq)/y or 0.76 and 0.79 GtCO2-eq/y during this period. Despite slower than projected increases in aggregate HCFC emissions since 2007, total emissions of HFCs used as substitutes for HCFCs and chlorofluorocarbons (CFCs) have not increased more rapidly than rates projected [Velders, G. J. M.; Fahey, D. W.; Daniel, J. S.; McFarland, M.; Andersen, S. O. The Large Contribution of Projected HFC Emissions to Future Climate Forcing. Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 10949-10954] for 2007-2012. HFC global emission magnitudes related to this substitution totaled 0.51 (-0.03, +0.04) GtCO2-eq/y in 2012, a magnitude about two times larger than emissions reported to the United Nations Framework Convention on Climate Change (UNFCCC) for these HFCs. Assuming accurate reporting to the UNFCCC, the results imply that developing countries (non-Annex I Parties) not reporting to the UNFCCC now account for nearly 50% of global HFC emissions used as substitutes for ozone-depleting substances (ODSs). Global HFC emissions (as CO2-eq) from ODS substitution can be attributed approximately equally to mobile air conditioning, commercial refrigeration, and the sum of all other applications.

Quantifying the relative contribution of natural gas fugitive emissions to total methane emissions in Colorado, Utah, and Texas using mobile isotopic methane analysis based on Cavity Ringdown Spectroscopy

NASA Astrophysics Data System (ADS)

Rella, Chris; Winkler, Renato; Sweeney, Colm; Karion, Anna; Petron, Gabrielle; Crosson, Eric

2014-05-01

Fugitive emissions of methane into the atmosphere are a major concern facing the natural gas production industry. Because methane is more energy-rich than coal per kg of carbon dioxide emitted into the atmosphere, it represents an attractive alternative to coal for electricity generation, provided that the fugitive emissions of methane are kept under control. A key step in assessing these emissions in a given region is partitioning the observed methane emissions between natural gas fugitive emissions and other sources of methane, such as from landfills or agricultural activities. One effective method for assessing the contribution of these different sources is stable isotope analysis, using the isotopic carbon signature to distinguish between natural gas and landfills or ruminants. We present measurements of methane using a mobile spectroscopic stable isotope analyzer based on cavity ringdown spectroscopy, in three intense natural gas producing regions of the United States: the Denver-Julesburg basin in Colorado, the Uintah basin in Utah, and the Barnett Shale in Texas. Performance of the CRDS isotope analyzer is presented, including precision, calibration, stability, and the potential for measurement bias due to other atmospheric constituents. Mobile isotope measurements of individual sources and in the nocturnal boundary layer have been combined to establish the fraction of the observed methane emissions that can be attributed to natural gas activities. The fraction of total methane emissions in the Denver-Julesburg basin attributed to natural gas emissions is 78 +/- 13%. In the Uinta basin, which has no other significant sources of methane, the fraction is 96% +/- 15%. In addition, results from the Barnett shale are presented, which includes a major urban center (Dallas / Ft. Worth). Methane emissions in this region are spatially highly heterogeneous. Spatially-resolved isotope and concentration measurements are interpreted using a simple emissions model to arrive at an overall isotope ratio for the region.

Evaluation of Mobile Source Emissions and Trends

NASA Astrophysics Data System (ADS)

Dallmann, Timothy Ryan

Mobile sources contribute significantly to air pollution problems. Relevant pollutants include numerous gaseous and particle-phase species that can affect human health, ecosystems, and climate. Accurate inventories of emissions from these sources are needed to help understand possible adverse impacts, and to develop effective air quality management strategies. Unfortunately large uncertainties persist in the understanding of mobile source emissions, and how these emissions are changing over time. This dissertation aims to evaluate long-term trends in mobile source emissions in the United States, and to make detailed measurements of emissions from present-day fleets of on-road vehicles operating in California. Long-term trends in mobile source emissions of nitrogen oxides (NO x) and fine particulate matter (PM2.5) in the United States were investigated through development of a fuel-based emission inventory. Annual emissions from on- and off-road gasoline and diesel engines were quantified for the years 1996-2006. Diesel engines were found to be the dominant mobile source of NOx and PM2.5, and on-road diesel vehicles were identified as the single largest anthropogenic source of NOx emissions in the United States as of 2005. The importance of diesel engines as a source of exhaust particulate matter emissions has led to the recent introduction of advanced emission control technologies in the United States, such as diesel particle filters (DPF), which have been required since 2007 for all new on-road heavy-duty (HD) diesel engines. In addition to national requirements for the use of such control devices on new engines, California has mandated accelerated clean-up of statewide emissions from older in-use diesel engines. The plume capture method was further applied to measure emissions from a more diverse population of trucks observed at the Caldecott tunnel in summer 2010. Emissions from hundreds of individual trucks were measured, and emission factor distributions were characterized for nitric oxide (NO), nitrogen dioxide (NO2), carbon monoxide (CO), formaldehyde, BC, as well as optical properties of the emitted particles. Emission factor distributions for all species were skewed, with a small fraction of trucks contributing disproportionately to total emissions. These findings confirm that the use of catalyzed DPF systems is leading to increased primary NO2 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. This value of aerosol SSA is very low compared to typical values (0.90-0.99) observed in ambient air studies. It is indicative of a strongly light-absorbing aerosol, due to the high BC emissions that are a characteristic feature of diesel exhaust PM emissions. Measurements at the Caldecott tunnel also included efforts to quantify light-duty (LD) gasoline vehicle emission factors, and further investigation of the relative contributions of on-road gasoline and diesel engines to air pollutant emissions. Measurements of CO, NOx, PM2.5, BC, and organic aerosol (OA) were made in a tunnel traffic bore where LD vehicles account for >99% of total traffic. Measured pollutant concentrations were apportioned between LD gasoline vehicles and diesel trucks, and fleet-average emission factors were quantified for LD gasoline vehicles using a carbon balance method. Diesel trucks contributed 18 +/- 3, 22 +/- 5, 44 +/- 8% of measured NOx, OA, and BC concentrations, respectively, despite accounting for <1% of total vehicles. Emission factors and overall fuel consumption for gasoline and diesel engines were used to describe the relative contributions of these sources to overall on-road vehicle emissions. Gasoline engines were found to be the dominant source of CO, an insignificant source of BC, and a relatively minor source of on-road OA emissions at urban, state, and national scales. Measurements at the Caldecott tunnel also featured use of a new high-resolution time-of-flight aerosol mass spectrometer, which was used to characterize the chemical composition of PM emitted by gasoline and diesel vehicles. Measurements of PM in the exhaust of individual HD trucks show a predominance of cyclyoalkane-derived ion signals relative to saturated alkane ion signals in the truck exhaust OA spectra, indicating that lubricating oil, rather than diesel fuel, was the dominant source of OA emitted by diesel trucks. This conclusion is supported by the presence of lubricant-derived trace elements in truck exhaust, emitted relative to total OA at levels that correspond to their weight fractions in bulk oil. Furthermore, comparison of mass spectra for sampling periods with varying levels of diesel influence found a high degree of similarity in the chemical composition of OA emitted by gasoline and diesel engines, suggesting a common lubricating oil rather than fuel-derived source for OA emissions. (Abstract shortened by UMI.).

CO2 Reduction Effect of the Utilization of Waste Heat and Solar Heat in City Gas System

NASA Astrophysics Data System (ADS)

Okamura, Tomohito; Matsuhashi, Ryuji; Yoshida, Yoshikuni; Hasegawa, Hideo; Ishitani, Hisashi

We evaluate total energy consumption and CO2 emissions in the phase of the city gas utilization system from obtaining raw materials to consuming the product. First, we develop a simulation model which calculates CO2 emissions for monthly and hourly demands of electricity, heats for air conditioning and hot-water in a typical hospital. Under the given standard capacity and operating time of CGS, energy consumption in the equipments is calculated in detail considering the partial load efficiency and the control by the temperature of exhaust heat. Then, we explored the optimal size and operation of city gas system that minimizes the life cycle CO2 emissions or total cost. The cost-effectiveness is compared between conventional co-generation, solar heat system, and hybrid co-generation utilizing solar heat. We formulate a problem of mixed integer programming that includes integral parameters that express the state of system devices such as on/off of switches. As a result of optimization, the hybrid co-generation can reduce annual CO2 emissions by forty-three percent compared with the system without co-generation. Sensitivity for the scale of CGS on CO2 reduction and cost is also analyzed.

30 CFR 250.218 - What air emissions information must accompany the EP?

Code of Federal Regulations, 2010 CFR

2010-07-01

... the EP? 250.218 Section 250.218 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... list: (i) The projected peak hourly emissions; (ii) The total annual emissions in tons per year; (iii... emissions; and (v) The total of all emissions listed in paragraphs (a)(1)(i) through (iv) of this section...

Resource Efficiency in the US Army Corps of Engineers: Examination of Strategies to Reduce Energy Use and Greenhouse Gas Emissions

DTIC Science & Technology

2012-09-15

Control 19 4,321 639 Office 10 4,387 584 Hydropower 5 2,885 504 2.1.2 NTV emissions NTV petroleum consumption information is a combination of ...reductions that will occur because of planned engine efficiency changes in the floating plant . These reductions total 8,956 MTCO2e. In addition, a ...and/or the implementation of a variety of measures such as passive solar energy, planting trees and plants around buildings to achieve desired

Emission of polycyclic aromatic hydrocarbons and their carcinogenic potencies from cooking sources to the urban atmosphere.

PubMed Central

Li, Chun-The; Lin, Yuan-Chung; Lee, Wen-Jhy; Tsai, Perng-Jy

2003-01-01

Traffic has long been recognized as the major contributor to polycyclic aromatic hydrocarbon (PAH) concentrations. However, this does not consider the contribution of cooking sources of PAHs. This study set out, first, to assess the characteristics of PAHs and their corresponding benzo[a]pyrene equivalent (B[a]Peq) emissions from cooking sources to the urban atmosphere. To illustrate the importance of cooking sources, PAH emissions from traffic sources were then calculated and compared. The entire study was conducted on a city located in southern Taiwan. PAH samples were collected from the exhaust stacks of four types of restaurant: Chinese, Western, fast food, and Japanese. For total PAHs, results show that the fractions of gaseous PAHs (range, 75.9-89.9%) were consistently higher than the fractions of particulate PAHs (range, 10.1-24.1%) in emissions from the four types of restaurant. But for total B[a]Peq, we found that the contributions of gaseous PAHs (range, 15.7-21.9%) were consistently lower than the contributions of particulate PAHs (range, 78.1-84.3%). For emission rates of both total PAHs and total B[a]Peq, a consistent trend was found for the four types of restaurant: Chinese (2,038 and 154 kg/year, respectively) > Western (258 and 20.4 kg/year, respectively) > fast food (31.4 and 0.104 kg/year, respectively) > Japanese (5.11 and 0.014 kg/year, respectively). By directly adapting the emission data obtained from Chinese restaurants, we found that emission rates on total PAHs and total B[a]Peq for home kitchen sources were 6,639 and 501 kg/year, respectively. By combining both restaurant sources and home kitchen sources, this study yielded emission rates of total PAHs and total B[a]Peq from cooking sources of the studied city of 8,973 and 675 kg/year, respectively. Compared with PAH emissions from traffic sources in the same city, we found that although the emission rates of total PAHs for cooking sources were significantly less than those for traffic sources (13,500 kg/year), the emission rates of total B[a]Peq for cooking sources were much higher than those for traffic sources (61.4 kg/year). The above results clearly indicate that although cooking sources are less important than traffic sources in contributing to total PAH emissions, PAH emissions from cooking sources might cause much more serious problems than traffic sources, from the perspective of carcinogenic potency. PMID:12676603

40 CFR 1054.230 - How do I select emission families?

Code of Federal Regulations, 2010 CFR

2010-07-01

...). (3) Valve configuration (for example, side-valve vs. overhead valve). (4) Method of air aspiration... configuration) and approximate total displacement. (7) Engine class, as defined in § 1054.801. (8) Method of control for engine operation, other than governing (mechanical or electronic). (9) The numerical level of...

Rumen fermentation and production effects of Origanum vulgare L. leaves in lactating dairy cows

USDA-ARS?s Scientific Manuscript database

A lactating cow trial was conducted to study the effects of dietary addition of oregano leaf material (Origanum vulgare L.; 0, control vs. 500 g/d, OV) on ruminal fermentation, methane production, total tract digestibility, manure gas emissions, N metabolism, organoleptic characteristics of milk, an...

40 CFR Table 4 to Subpart Xxxx of... - Operating Limits for Puncture Sealant Application Control Devices

Code of Federal Regulations, 2011 CFR

2011-07-01

... performance test. 2. Carbon adsorber (regenerative) to which puncture sealant application spray booth emissions are ducted a. Maintain the total regeneration mass, volumetric flow, and carbon bed temperature at the operating range established during the performance test.b. Reestablish the carbon bed temperature...

40 CFR 63.750 - Test methods and procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Test methods and procedures. 63.750...) National Emission Standards for Aerospace Manufacturing and Rework Facilities § 63.750 Test methods and... period as part of an ambient ozone control program. (1)(i) Determine the total organic HAP weight...

40 CFR 63.750 - Test methods and procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Test methods and procedures. 63.750...) National Emission Standards for Aerospace Manufacturing and Rework Facilities § 63.750 Test methods and... period as part of an ambient ozone control program. (1)(i) Determine the total organic HAP weight...

40 CFR 63.750 - Test methods and procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Test methods and procedures. 63.750...) National Emission Standards for Aerospace Manufacturing and Rework Facilities § 63.750 Test methods and... period as part of an ambient ozone control program. (1)(i) Determine the total organic HAP weight...

40 CFR 63.750 - Test methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Test methods and procedures. 63.750...) National Emission Standards for Aerospace Manufacturing and Rework Facilities § 63.750 Test methods and... period as part of an ambient ozone control program. (1)(i) Determine the total organic HAP weight...

40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... single highest-HAP recipe. (3) Total annual uncontrolled TOC or organic HAP emissions, determined at the...): (i) For an incinerator or non-combustion control device, the percent reduction of organic HAP or TOC... percent reduction of organic HAP or TOC achieved, as determined using the procedures specified in § 63...

40 CFR 20.8 - Requirements for certification.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the useful life, or (C) reduce the total operating costs of the operating unit (of the plant or other... policies of the United States and the States in the prevention and abatement of air pollution, the Regional... directed; (3) Local government requirements for control of air pollution, including emission standards; (4...

40 CFR 20.8 - Requirements for certification.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the useful life, or (C) reduce the total operating costs of the operating unit (of the plant or other... policies of the United States and the States in the prevention and abatement of air pollution, the Regional... directed; (3) Local government requirements for control of air pollution, including emission standards; (4...

40 CFR 20.8 - Requirements for certification.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the useful life, or (C) reduce the total operating costs of the operating unit (of the plant or other... policies of the United States and the States in the prevention and abatement of air pollution, the Regional... directed; (3) Local government requirements for control of air pollution, including emission standards; (4...

40 CFR 20.8 - Requirements for certification.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the useful life, or (C) reduce the total operating costs of the operating unit (of the plant or other... policies of the United States and the States in the prevention and abatement of air pollution, the Regional... directed; (3) Local government requirements for control of air pollution, including emission standards; (4...

40 CFR 20.8 - Requirements for certification.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the useful life, or (C) reduce the total operating costs of the operating unit (of the plant or other... policies of the United States and the States in the prevention and abatement of air pollution, the Regional... directed; (3) Local government requirements for control of air pollution, including emission standards; (4...

High-speed civil transport study: Special factors

NASA Technical Reports Server (NTRS)

1990-01-01

Studies relating to environmental factors associated with high speed civil transports were conducted. Projected total engine emissions for year 2015 fleets of several subsonic/supersonic transport fleet scenarios, discussion of sonic boom reduction methods, discussion of community noise level requirements, fuels considerations, and air traffic control impact are presented.

40 CFR 62.7853 - Identification of plan-negative declaration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... chapter. (b) Letters from the City of Albuquerque Air Pollution Control Division dated July 8, 1980, and... declaration. 62.7853 Section 62.7853 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Mexico Total Reduced Sulfur Emissions from Kraft Pulp Mills § 62.7853 Identification of plan—negative...

40 CFR 62.7853 - Identification of plan-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... chapter. (b) Letters from the City of Albuquerque Air Pollution Control Division dated July 8, 1980, and... declaration. 62.7853 Section 62.7853 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Mexico Total Reduced Sulfur Emissions from Kraft Pulp Mills § 62.7853 Identification of plan—negative...

40 CFR 62.7853 - Identification of plan-negative declaration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... chapter. (b) Letters from the City of Albuquerque Air Pollution Control Division dated July 8, 1980, and... declaration. 62.7853 Section 62.7853 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Mexico Total Reduced Sulfur Emissions from Kraft Pulp Mills § 62.7853 Identification of plan—negative...

40 CFR 60.581 - Definitions and symbols.

Code of Federal Regulations, 2011 CFR

2011-07-01

... image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's...=the concentration of VOC in each gas stream (j) for the time period exiting the emission control... plant records, in kilograms. Mdj=the total mass of each dilution solvent (j) added at the print line in...

40 CFR 60.581 - Definitions and symbols.

Code of Federal Regulations, 2014 CFR

2014-07-01

... image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's... = the concentration of VOC in each gas stream (j) for the time period exiting the emission control... determined from plant records, in kilograms. Mdj = the total mass of each dilution solvent (j) added at the...

40 CFR 60.581 - Definitions and symbols.

Code of Federal Regulations, 2010 CFR

2010-07-01

... image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's...=the concentration of VOC in each gas stream (j) for the time period exiting the emission control... plant records, in kilograms. Mdj=the total mass of each dilution solvent (j) added at the print line in...

40 CFR 60.581 - Definitions and symbols.

Code of Federal Regulations, 2013 CFR

2013-07-01

... image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's...=the concentration of VOC in each gas stream (j) for the time period exiting the emission control... plant records, in kilograms. Mdj=the total mass of each dilution solvent (j) added at the print line in...

40 CFR 60.581 - Definitions and symbols.

Code of Federal Regulations, 2012 CFR

2012-07-01

... image consisting of minute cells or indentations, specifically engraved or etched into the cylinder's...=the concentration of VOC in each gas stream (j) for the time period exiting the emission control... plant records, in kilograms. Mdj=the total mass of each dilution solvent (j) added at the print line in...

Woodbridge Research Facility Remedial Investigation/Feasibility Study; Focused Feasibility Study for Operable Unit Three

DTIC Science & Technology

1997-11-01

TCL Target Compound List TCLP toxicity characteristic leachate procedure TPH Total Petroleum Hydrocarbon TRV toxicity reference value TSCA...controlled environment where temperature, nutrients, and oxygen can be controlled. Gaseous emissions and leachate can also be collected and treated...wood chip mixture was then spread over a gravel base enclosed in HDPE. The treatment beds were aerated with blowers and leachate was collected in a

Non-agricultural ammonia emissions in urban China

NASA Astrophysics Data System (ADS)

Chang, Y. H.

2014-03-01

The non-agricultural ammonia (NH3) emissions in cities have received little attention but could rival agricultural sources in term of the efficiency in PM formation. The starting point for finding credible solutions is to comprehensively establish a city-specific Non-agricultural Ammonia Emission Inventory (NAEI) and identify the largest sources where efforts can be directed to deliver the largest impact. In this paper, I present a NAEI of 113 national key cities targeted on environmental protection in China in 2010, which for the first time covers NH3 emissions from pets, infants, smokers, green land, and household products. Results show that totally 210 478 Mg, the NH3 emissions from traffic, fuel combustion, waste disposal, pets, green land, human, and household products are 67 671 Mg, 56 275 Mg, 44 289 Mg, 23 355 Mg, 7509 Mg, 7312 Mg, and 4069 Mg, respectively. The NH3 emission intensity from the municipal districts ranges from 0.08 to 3.13 Mg km-2 yr-1, with a average of 0.84 Mg km-2 yr-1. The high NH3 emission intensities in Beijing-Tianjin-Hebei region, Yangtze River Delta region and Pearl River Delta region support the view that non-agricultural NH3 sources play a key role in city-scale NH3 emissions and thus have potentially important implications for secondary PM formation (ammonium-sulfate-nitrate system) in urban agglomeration of China. Therefore, in addition to current SO2 and NOx controls, China also needs to allocate more scientific, technical, and legal resources on controlling non-agricultural NH3 emissions in the future.

[Study on strategies of pollution prevention in coastal city of Zhejiang Province based on scenario analysis].

PubMed

Tian, Jin-Ping; Chen, Lü-Jun; Du, Peng-Fei; Qian, Yi

2013-01-01

Scenario analysis was used to study the environmental burden in a coastal city of Zhejiang province under different patterns of economic development. The aim of this research is to propose advices on decision making by illustrating how to make emissions reduced by transforming the pattern of economic development in a developed coastal area, which had acquired the level of 70 000 yuan GDP per cap. At first, 18 heavy pollution industries were screened out, by referencing total emissions of chemical oxygen demand, ammonia-nitrogen, sulfur dioxide, and nitrogen oxide. Then, a model of scenario analysis and the back-up calculation program were designed to study the sustainable development of the heavy pollution industries. With 2008 and 2015 as the reference year and the target year respectively, emissions of four pollutants mentioned above in the 18 heavy pollution industries in the city were analyzed under six scenarios. The total emissions of 4 pollutants should be reduced to an expectant degree, which is set as the constraint prerequisite of the scenario analysis. At last, some suggestions for decision-making are put forward, which include maintaining a moderate increase rate of GDP around 7%, strengthening the adjustment of economic structure, controlling the increasing rate of industrial added value of the industries with heavy pollution, optimizing the structure of industries with heavy pollution, decreasing the intensity of waste emission by implementing cleaner production to reduce emission produce at the source, and strengthening regulations on the operation of waste treatment plants to further promote the efficiency of waste treatment. Only by implementing such measures mentioned above, can the total emissions of chemical oxygen demand, ammonia-nitrogen, sulfur dioxide, and nitrogen oxide of the 18 industries with heavy pollution in the city be reduced by a 10%, 10%, 5%, and 15% respectively based on the reference year.

[CH4 emission features of leading super-rice varieties and their relationships with the varieties growth characteristics in Yangtze Delta of China].

PubMed

Yan, Xiao-Jun; Wang, Li-Li; Jiang, Yu; Deng, Ai-Xing; Tian, Yun-Lu; Zhang, Wei-Jian

2013-09-01

A pot experiment was conducted to study the CH4 emission features of fourteen leading super-rice varieties (six Japonica rice varieties and eight Indica hybrid rice varieties) and their relationships with the varieties growth characteristics in Yangtze Delta. Two distinct peaks of CH4 emission were detected during the entire growth period of the varieties, one peak occurred at full-tillering stage, and the other appeared at booting stage. The average total CH4 emission of Japonica rice varieties was 37.6% higher than that of the Indica hybrid rice varieties (P<0.01), and the differences in the CH4 emission between rice types occurred at the post-anthesis phase. For all the varieties, there was a significant positive correlation between the total CH4 emission and the maximum leaf area, but the correlations between the CH4 emission and the other growth characteristics varied with variety type. The total CH4 emission of Japonica rice varieties had a significant positive correlation with plant height, while the correlations between the total CH4 emission of Indica hybrid rice varieties and their plant height were not significant. The total CH4 emission of Indica hybrid rice varieties had significant negative correlations with the total aboveground biomass, grain yield, and harvest index, but the correlations were not significant for Japonica rice varieties. The lower CH4 emission of Indica hybrid rice varieties was likely due to their significantly higher root biomass, as compared with Japonica rice varieties.

[Effects of different fertilization measures on N2O emission in oil sunflower field in irrigation area of upper Yellow River].

PubMed

Chen, Zhe; Chen, Yuan-yuan; Gao, Ji; Liu, Ru-liang; Yang, Zheng-li; Zhang, Ai-ping

2015-01-01

Agricultural soil has become the largest anthropogenic source of atmospheric nitrous oxide (N20). To estimate the impacts of long-term combined application of organic and inorganic fertilizers on N20 emission in a typical winter wheat-oil sunflower cropping system in the Ningxia irrigation area, we measured N20 fluxes using the static opaque chamber-gas chromatograph method and monitored the seasonal dynamics of related factors. Our results showed that nitrogen addition in the previous crop field significantly stimulated N2O emissions during the following oil-sunflower cultivation, and the mean fluxes of N300-OM, N240-OM1/2, N300 and N240 were (34.16 ± 9.72), (39.69 ±10.70), (27.75 ±9.57) and (26.30 ± 8.52) µg . m-2 . h-1, respectively, which were 4.09, 4.75, 3.32 and 3.15 times of the control groups. The total cumulative N2O emissions of fertilizer treatments in growing season was as high as 796.7 to 1242.5 g . hm-2, which was 2.99 to 4.67 times of the control groups. During the growing season, the rates of N2O emission in each month organic and inorganic fertlizers combined treatments were similar at high levels. N2O emission in chemical fertilizer treatments gradually decreased, and the main period of N2O emission occurred at the beginning of growing season. Taking July for example, N2O emission accounted for 41.3% to 41. 8% of total cumulative amount. The amounts of N20 emission under organic and inorganic fertilizers combined treatments were significantly higher than under chemical fertilizer treatments. The N2O emissions were not significantly different between conventional and optimized applications of nitrogen fertilizer under the same fertilizing method, either between N300-OM and N240-OM1/2, or between N300 and N240. On account of the drought, N2O emission in each treatment was mainly affected by soil moisture. N2O emission had a significant positive correlation with soil ammonium nitrogen content under combined applications of organic and inorganic fertilizers, but was not correlated with soil nitrate nitrogen content under all treatments. This showed that adding organic fertilizer could stimulate the NO2 production via increasing the soil ammonium nitrogen content.

Methane Emissions from the Inland Waters of Alaska

NASA Astrophysics Data System (ADS)

Striegl, R. G.; Butman, D. E.; Stackpoole, S. M.; Dornblaser, M.

2017-12-01

Inland waters at high latitudes generally emit methane (CH4) continuously to the atmosphere during the open water season and build-up CH4 under ice during winter that is released over a short period following ice melt. Landscape position, stream and river size, water source, and turbulence created by water flow largely control CH4 emissions from streams and rivers. Organic carbon sources for CH4 production in lakes vary widely among lakes and landscapes and include hydrologic inputs from terrestrial sources, releases from permafrost thaw (thermokarst), and autochthonous inputs from aquatic macrophytes and algae. Lake emissions are therefore controlled by the balance between within-lake CH4 production and consumption, surface turbulence at the water-air interface, and CH4 ebullition. This creates a complex range of conditions that are difficult to characterize, where dissolved CH4 concentrations may vary by up to 4 orders of magnitude among lakes and/or within a single lake over an annual seasonal cycle. Moreover, large inputs of organic matter from permafrost thaw or other sources commonly result in high rates of bubble production and ebullition from some lakes, while other lakes have negligible ebullition. We quantified water surface areas and estimated CH4 emission rates for lakes, streams and rivers for the six major hydrologic regions of Alaska and determined that they collectively emit about 0.124 Tg C per year as CH4 to the atmosphere. Lake emissions comprise about 75% of the total. When adjusted for total land surface area in Alaska, our lake emission estimate is substantially smaller than previous global estimates for inland waters north of 50 degrees North latitude. We attribute this to incorporation of results that cover a broad range of lake conditions in interior Alaska and to new data from lakes in southwest Alaska that have very low CH4 concentration but very large surface area.

Current status and prediction of major atmospheric emissions from coal-fired power plants in Shandong Province, China

NASA Astrophysics Data System (ADS)

Xiong, Tianqi; Jiang, Wei; Gao, Weidong

2016-01-01

Shandong is considered to be the top provincial emitter of air pollutants in China due to its large consumption of coal in the power sector and its dense distribution of coal-fired plants. To explore the atmospheric emissions of the coal-fired power sector in Shandong, an updated emission inventory of coal-fired power plants for the year 2012 in Shandong was developed. The inventory is based on the following parameters: coal quality, unit capacity and unit starting year, plant location, boiler type and control technologies. The total SO2, NOx, fine particulate matter (PM2.5) and mercury (Hg) emissions are estimated at 705.93 kt, 754.30 kt, 63.99 kt and 10.19 kt, respectively. Larger units have cleaner emissions than smaller ones. The coal-fired units (≥300 MW) are estimated to account for 35.87% of SO2, 43.24% of NOx, 47.74% of PM2.5 and 49.83% of Hg emissions, which is attributed primarily to the improved penetration of desulfurization, LNBs, denitration and dust-removing devices in larger units. The major regional contributors are southwestern cities, such as Jining, Liaocheng, Zibo and Linyi, and eastern cities, such as Yantai and Qindao. Under the high-efficiency control technology (HECT) scenario analysis, emission reductions of approximately 58.61% SO2, 80.63% NOx, 34.20% PM2.5 and 50.08% Hg could be achieved by 2030 compared with a 2012 baseline. This inventory demonstrates why it is important for policymakers and researchers to assess control measure effectiveness and to supply necessary input for regional policymaking and the management of the coal-fired power sector in Shandong.

Environmental assessment of a wood-waste-fired industrial firetube boiler. Volume 1. Technical results. Final report, January 1981-March 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeRosier, R.; Waterland, L.R.

1987-03-01

The report gives emission results from field tests of a wood-waste-fired industrial firetube boiler. Emission measurements included: continuous monitoring of flue gas emissions: source assessment sampling system (SASS) sampling of the flue-gas with subsequent laboratory analysis of samples to give total flue gas organics in two boiling point ranges, compound category information within these ranges, specific quantitation of the semivolatile organic priority pollutants, and flue gas concentrations of 65 trace elements; Method 5 sampling for particulates; controlled condensation system (CSS) sampling for SO/sub 2/ and SO/sub 3/; and grab sampling of boiler bottom ash for trace element content determinations. Totalmore » organic emissions from the boiler were 5.7 mg/dscm, about 90% of which consisted of volatile compounds.« less

Comparative study of radiometric and calorimetric methods for total hemispherical emissivity measurements

NASA Astrophysics Data System (ADS)

Monchau, Jean-Pierre; Hameury, Jacques; Ausset, Patrick; Hay, Bruno; Ibos, Laurent; Candau, Yves

2018-05-01

Accurate knowledge of infrared emissivity is important in applications such as surface temperature measurements by infrared thermography or thermal balance for building walls. A comparison of total hemispherical emissivity measurement was performed by two laboratories: the Laboratoire National de Métrologie et d'Essais (LNE) and the Centre d'Études et de Recherche en Thermique, Environnement et Systèmes (CERTES). Both laboratories performed emissivity measurements on four samples, chosen to cover a large range of emissivity values and angular reflectance behaviors. The samples were polished aluminum (highly specular, low emissivity), bulk PVC (slightly specular, high emissivity), sandblasted aluminum (diffuse surface, medium emissivity), and aluminum paint (slightly specular surface, medium emissivity). Results obtained using five measurement techniques were compared. LNE used a calorimetric method for direct total hemispherical emissivity measurement [1], an absolute reflectometric measurement method [2], and a relative reflectometric measurement method. CERTES used two total hemispherical directional reflectometric measurement methods [3, 4]. For indirect techniques by reflectance measurements, the total hemispherical emissivity values were calculated from directional hemispherical reflectance measurement results using spectral integration when required and directional to hemispherical extrapolation. Results were compared, taking into account measurement uncertainties; an added uncertainty was introduced to account for heterogeneity over the surfaces of the samples and between samples. All techniques gave large relative uncertainties for a low emissive and very specular material (polished aluminum), and results were quite scattered. All the indirect techniques by reflectance measurement gave results within ±0.01 for a high emissivity material. A commercial aluminum paint appears to be a good candidate for producing samples with medium level of emissivity (about 0.4) and with good uniformity of emissivity values (within ±0.015).

Chapter 2: Livestock and Grazed Lands Emissions

USDA-ARS?s Scientific Manuscript database

A total of 342 MMT CO2 eq. of greenhouse gasses (GHGs) were emitted from livestock, managed livestock waste, and grazed land in 2013. This represents about 66% of total emissions from the agricultural sector, which totaled 516 MMT CO2 eq. Compared to the base line year (1990), emissions from livesto...

Programmable thermal emissivity structures based on bioinspired self-shape materials

NASA Astrophysics Data System (ADS)

Athanasopoulos, N.; Siakavellas, N. J.

2015-12-01

Programmable thermal emissivity structures based on the bioinspired self-shape anisotropic materials were developed at macro-scale, and further studied theoretically at smaller scale. We study a novel concept, incorporating materials that are capable of transforming their shape via microstructural rearrangements under temperature stimuli, while avoiding the use of exotic shape memory materials or complex micro-mechanisms. Thus, programmed thermal emissivity behaviour of a surface is achievable. The self-shape structure reacts according to the temperature of the surrounding environment or the radiative heat flux. A surface which incorporates self-shape structures can be designed to quickly absorb radiative heat energy at low temperature levels, but is simultaneously capable of passively controlling its maximum temperature in order to prevent overheating. It resembles a “game” of colours, where two or more materials coexist with different values of thermal emissivity/ absorptivity/ reflectivity. The transformation of the structure conceals or reveals one of the materials, creating a surface with programmable - and therefore, variable- effective thermal emissivity. Variable thermal emissivity surfaces may be developed with a total hemispherical emissivity ratio (ɛEff_H/ɛEff_L) equal to 28.

Broadband UV spectroscopy system used for monitoring of SO 2 and NO emissions from thermal power plants

NASA Astrophysics Data System (ADS)

Zhang, Y. G.; Wang, H. S.; Somesfalean, G.; Wang, Z. Y.; Lou, X. T.; Wu, S. H.; Zhang, Z. G.; Qin, Y. K.

2010-11-01

A gas monitoring system based on broadband absorption spectroscopic techniques in the ultraviolet region is described and tested. The system was employed in real-time continuous concentration measurements of sulfur dioxide (SO 2) and nitric oxide (NO) from a 220-ton h -1 circulating fluidized bed (CFB) boiler in Shandong province, China. The emission coefficients (per kg of coal and per kWh of electricity) and the total emission of the two pollutant gases were evaluated. The measurement results showed that the emission concentrations of SO 2 and NO from the CFB boiler fluctuated in the range of 750-1300 mg m -3 and 100-220 mg m -3, respectively. Compared with the specified emission standards of air pollutants from thermal power plants in China, the values were generally higher for SO 2 and lower for NO. The relatively high emission concentrations of SO 2 were found to mainly depend on the sulfur content of the fuel and the poor desulfurization efficiency. This study indicates that the broadband UV spectroscopy system is suitable for industrial emission monitoring and pollution control.

Programmable thermal emissivity structures based on bioinspired self-shape materials

PubMed Central

Athanasopoulos, N.; Siakavellas, N. J.

2015-01-01

Programmable thermal emissivity structures based on the bioinspired self-shape anisotropic materials were developed at macro-scale, and further studied theoretically at smaller scale. We study a novel concept, incorporating materials that are capable of transforming their shape via microstructural rearrangements under temperature stimuli, while avoiding the use of exotic shape memory materials or complex micro-mechanisms. Thus, programmed thermal emissivity behaviour of a surface is achievable. The self-shape structure reacts according to the temperature of the surrounding environment or the radiative heat flux. A surface which incorporates self-shape structures can be designed to quickly absorb radiative heat energy at low temperature levels, but is simultaneously capable of passively controlling its maximum temperature in order to prevent overheating. It resembles a “game” of colours, where two or more materials coexist with different values of thermal emissivity/ absorptivity/ reflectivity. The transformation of the structure conceals or reveals one of the materials, creating a surface with programmable – and therefore, variable- effective thermal emissivity. Variable thermal emissivity surfaces may be developed with a total hemispherical emissivity ratio (εEff_H/εEff_L) equal to 28. PMID:26635316

30 CFR 250.249 - What air emissions information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... the DPP or DOCD? 250.249 Section 250.249 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF... must list: (i) The projected peak hourly emissions; (ii) The total annual emissions in tons per year... frequency and duration of emissions; and (v) The total of all emissions listed in paragraph (a)(1)(i...

Effect of soil texture and chemical properties on laboratory-generated dust emissions from SW North America

NASA Astrophysics Data System (ADS)

Mockford, T.; Zobeck, T. M.; Lee, J. A.; Gill, T. E.; Dominguez, M. A.; Peinado, P.

2012-12-01

Understanding the controls of mineral dust emissions and their particle size distributions during wind-erosion events is critical as dust particles play a significant impact in shaping the earth's climate. It has been suggested that emission rates and particle size distributions are independent of soil chemistry and soil texture. In this study, 45 samples of wind-erodible surface soils from the Southern High Plains and Chihuahuan Desert regions of Texas, New Mexico, Colorado and Chihuahua were analyzed by the Lubbock Dust Generation, Analysis and Sampling System (LDGASS) and a Beckman-Coulter particle multisizer. The LDGASS created dust emissions in a controlled laboratory setting using a rotating arm which allows particle collisions. The emitted dust was transferred to a chamber where particulate matter concentration was recorded using a DataRam and MiniVol filter and dust particle size distribution was recorded using a GRIMM particle analyzer. Particle size analysis was also determined from samples deposited on the Mini-Vol filters using a Beckman-Coulter particle multisizer. Soil textures of source samples ranged from sands and sandy loams to clays and silts. Initial results suggest that total dust emissions increased with increasing soil clay and silt content and decreased with increasing sand content. Particle size distribution analysis showed a similar relationship; soils with high silt content produced the widest range of dust particle sizes and the smallest dust particles. Sand grains seem to produce the largest dust particles. Chemical control of dust emissions by calcium carbonate content will also be discussed.

A high temporal-spatial vehicle emission inventory based on detailed hourly traffic data in a medium-sized city of China.

PubMed

Liu, Yong-Hong; Ma, Jin-Ling; Li, Li; Lin, Xiao-Fang; Xu, Wei-Jia; Ding, Hui

2018-05-01

To improve the accuracy and temporal-spatial resolution for a vehicle emission inventory in a medium-sized city with a strip road network, this study was conducted based on detailed hourly traffic-flow data for each day of 2014, and covered all road types and regions in the city of Foshan. Detailed hourly emission characteristics and sources in five regions were analysed. The results showed that the total vehicle emissions of CO, NO X , VOCs, and PM 2.5 were 13.10 × 10 4 , 0.23 × 10 4 , 4.46 × 10 4 , and 0.18 × 10 4 tons, respectively. Motorcycles (MCs) and light passenger cars (LPCs) were the dominant contributors of CO emissions, while buses and heavy passenger cars (HPCs) were the dominant contributors for NO X . As a whole, the daytime contributions to total emissions were close to 80%, and emissions during the peak periods accounted for almost 40%. Specifically, the hourly emissions of each pollutant on workdays were higher than on non-workdays (maximum up to 64.2%), and for some roads the early peak periods changed significantly from workdays to non-workdays. At expressways, artery roads, and local roads, the daily emission intensities of CO, NOx, and PM 2.5 in Foshan were close to or even higher than that of Beijing. On a regional scale, the temporal variation of vehicle emissions on workdays at artery roads of different regions were similar. In addition, the higher emission intensities of CO and VOCs were identified in DaLiang-RongGui (DLRG) and that of NO X and PM 2.5 were in Central Region (CR). These results are meaningful for decision-makers to help provide more detailed vehicle pollution control measures in Foshan with a strip road network and only one ring road. Copyright © 2018 Elsevier Ltd. All rights reserved.

Enhanced NH3 emission from swine liquid waste

NASA Astrophysics Data System (ADS)

Lee, S.; Robarge, W. P.; Walker, J. T.

2010-12-01

Swine animal feeding operations are sources of emissions for various gases [ammonia (NH3), hydrogen sulfide (H2S), carbon dioxide (CO2), volatile organic carbons (VOCs)], and fine particulate matter. Gaseous emissions from simple aqueous systems are typically controlled by temperature, pH, wind speed, total dissolved concentration of the chemical species of interest (e.g. NH3+NH4+ = TAN), and the Henry’s law constant. Ammonia emissions from three different sources [ammonium sulfate (AS), swine anaerobic lagoon liquid (SLL), and pit liquid (SPL) from swine housing units] were evaluated using a small flow-through teflon-lined chamber (SFTC; 0.3m × 0.2m × 0.15m) under controlled laboratory conditions. The SFTC was designed for 100% collection efficiency of NH3 gas emitted from the liquids. The internal volume of the chamber, 9 L, was exchanged 1.1 times per minute. All three liquid formulations exhibit the expected response in emissions with changes in temperature and pH. However, NH3 emissions from the SPL and SLL are ~5 times those from pure solutions of AS. Furthermore, the enhancement in NH3 emissions was a function of TAN concentration, decreasing in intensity at higher TAN and approaching rates comparable to the pure solutions of AS. The difference in emissions with solutions of equivalent TAN suggests a synergistic mechanism that is enhancing NH3 emissions in SPL and SLL. Concurrent measurements as part of the National Air Emissions Monitoring Study at the swine operations originally sampled for SPL and SLL document the emissions of CO2, H2S and VOCs (primarily acetic, propionic and butyric acids) at levels that are comparable to observed NH3 emissions. To date, only additions of NaHCO3 to the SPL and SLL have been found to enhance NH3 emissions and exhibit the same response to increasing TAN as exhibited by the original SPL and SLL solutions. Possible reactions that could enhance emissions will be discussed.

Direct measurements of methane emissions from abandoned oil and gas wells in Pennsylvania

PubMed Central

Kang, Mary; Kanno, Cynthia M.; Reid, Matthew C.; Zhang, Xin; Mauzerall, Denise L.; Celia, Michael A.; Chen, Yuheng; Onstott, Tullis C.

2014-01-01

Abandoned oil and gas wells provide a potential pathway for subsurface migration and emissions of methane and other fluids to the atmosphere. Little is known about methane fluxes from the millions of abandoned wells that exist in the United States. Here, we report direct measurements of methane fluxes from abandoned oil and gas wells in Pennsylvania, using static flux chambers. A total of 42 and 52 direct measurements were made at wells and at locations near the wells (“controls”) in forested, wetland, grassland, and river areas in July, August, October 2013 and January 2014, respectively. The mean methane flow rates at these well locations were 0.27 kg/d/well, and the mean methane flow rate at the control locations was 4.5 × 10−6 kg/d/location. Three out of the 19 measured wells were high emitters that had methane flow rates that were three orders of magnitude larger than the median flow rate of 1.3 × 10−3 kg/d/well. Assuming the mean flow rate found here is representative of all abandoned wells in Pennsylvania, we scaled the methane emissions to be 4–7% of estimated total anthropogenic methane emissions in Pennsylvania. The presence of ethane, propane, and n-butane, along with the methane isotopic composition, indicate that the emitted methane is predominantly of thermogenic origin. These measurements show that methane emissions from abandoned oil and gas wells can be significant. The research required to quantify these emissions nationally should be undertaken so they can be accurately described and included in greenhouse gas emissions inventories. PMID:25489074

Wildfire and soil emissions of NOx and their consequences for ozone observed at a remote mountaintop site in Central California

NASA Astrophysics Data System (ADS)

Asher, E. C. C.; Caputi, D.; Conley, S. A.; Faloona, I. C.

2016-12-01

Nitric oxide (NOx) emissions contribute to the production of tropospheric ozone and the nutrient supply fueling primary production. Current global estimates indicate that biomass burning, including wildfires, and soil emissions represent 15 - 25 % of the total emissions. Yet estimates suggest that in North America during the summer, natural sources, including biomass burning, soil emissions and lightning, are responsible for nearly half of total emissions. Thus, as domestic air quality standards grow stricter and anthropogenic sources more regulated, constraining natural sources of NOx becomes critical. NOx concentrations in wildfire smoke differ based on the age of the plume, fire intensity and vegetation type. NOx soil emissions depend on soil moisture, soil temperature, soil porosity, and nitrogen storage. We present two years of NOx and ozone (O3) measurements from a remote mountaintop monitoring site located on Chews Ridge in the coastal mountains of Central California, airborne observations, and remotely sensed NO2 tropospheric columns retrieved using the Ozone Monitoring Instrument (OMI). We explore controls on NOx concentrations at Chews Ridge, in Monterey County, such as the age of wildfire smoke plumes and wildfire intensity (i.e. burning vs. smoldering), as well as soil moisture and precipitation, which can lead to pulsed NOx fluxes. Most recently our in situ observations fortuitously captured differing amounts of the active plume of the Soberanes wildfire, which to date has burned >45,000 acres and is expected to continue partially contained through August 2016. Implications of these episodic sources of NOx on the regional ozone budget will be discussed.

Current and future emissions of primary pollutants from coal-fired power plants in Shaanxi, China.

PubMed

Xu, Yong; Hu, Jianlin; Ying, Qi; Hao, Hongke; Wang, Dexiang; Zhang, Hongliang

2017-10-01

A high-resolution inventory of primary atmospheric pollutants from coal-fired power plants in Shaanxi in 2012 was built based on a detailed database compiled at unit level involving unit capacity, boiler size and type, commission time, corresponding control technologies, and average coal quality of 72 power plants. The pollutants included SO 2 , NO x , fine particulate matter (PM 2.5 ), inhalable particulate matter (PM 10 ), organic carbon (OC), elemental carbon (EC), carbon monoxide (CO) and non-methane volatile organic compounds (NMVOC). Emission factors for SO 2 , NO x , PM 2.5 and PM 10 were adopted from standardized official promulgation, supplemented by those from local studies. The estimated annual emissions of SO 2 , NO x , PM 2.5 , PM 10 , EC, OC, CO and NMVOC were 152.4, 314.8, 16.6, 26.4, 0.07, 0.27, 64.9 and 2.5kt, respectively. Small units (<100MW), which accounted for ~60% of total unit numbers, had less coal consumption but higher emission rates compared to medium (≥100MW and <300MW) and large units (≥300MW). Main factors affecting SO 2 , NO x , PM 2.5 and PM 10 emissions were decontamination efficiency, sulfur content and ash content of coal. Weinan and Xianyang were the two cities with the highest emissions, and Guanzhong Plain had the largest emission density. Despite the projected growth of coal consumption, emissions would decrease in 2030 due to improvement in emission control technologies and combustion efficiencies. SO 2 and NO x emissions would experience significant reduction by ~81% and ~84%, respectively. PM 2.5 , PM 10 , EC and OC would be decreased by ~43% and CO and NMVOC would be reduced by ~16%. Copyright © 2017 Elsevier B.V. All rights reserved.

Biofilter application for control of BTEX compounds from glycol dehydrator condenser vent gases at oil and natural gas producing facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stewart, W.C.; Kamarthi, R.S.

1997-12-31

Compliance with 1990 Clean Air Act Amendments will require cost-effective control technologies to reduce air emissions for petroleum industries. EPA has also proposed a new MACT Rule for Oil and Natural Gas Producing Facilities which will require control of emissions from glycol dehydrator vents. Control of volatile organic compound (VOC) emissions such as benzene, toluene, ethylbenzene, and xylene (BTEX) is one of the major concerns for the petroleum industries. Traditional VOC control methods may not be economically feasible to meet the requirements of these regulations. Recent studies have shown that biofilters can cost-effectively remove BTEX compounds with greater than 95%more » efficiency. This paper describes results from field testing a biofilter at an Oil and Natural Gas Producing facility. The biofilter treats a low flow gas stream containing high concentrations of VOCs and carbon dioxide from a glycol dehydrator condenser vent. A modular high-rate vapor phase biofilter developed by BioiReaction Industries was used to investigate the feasibility of this low-cost technology. Due to the high VOC loading (BTEX compounds up to 18,000 ppm; total VOCs 50,000 to 90,000 ppm), three modular biofilters were installed in series.« less

Emission of volatile organic sulfur compounds (VOSCs) during aerobic decomposition of food wastes

NASA Astrophysics Data System (ADS)

Wu, Ting; Wang, Xinming; Li, Dejun; Yi, Zhigang

2010-12-01

Food wastes collected from typical urban residential communities were investigated for the emission of volatile organic sulfur compounds (VOSCs) during laboratory-controlled aerobic decomposition in an incubator for a period of 41 days. Emission of VOSCs from the food wastes totaled 409.9 mg kg -1 (dry weight), and dimethyl disulfide (DMDS), dimethyl sulfide (DMS), methyl 2-propenyl disulfide, carbonyl sulfide and methyl 1-propenyl sulfide were the five most abundant VOSCs, with shares of 75.5%, 13.5%, 4.8%, 2.2% and 1.3% in total 15 VOSCs released, respectively. The emission fluxes of major VOSCs were very low at the beginning (day 0). They peaked at days 2-4 and then decreased sharply until they leveled off after 10 days of incubation. For most VOSCs, over 95% of their emission occurred in the first 10 days. The time series of VOSC emission fluxes, as well as their significant correlation with internal food waste temperature ( p < 0.05) during incubation, suggested that production of VOSC species was induced mainly by microbial activities during the aerobic decomposition instead of as inherited. Released VOSCs accounted for 5.3% of sulfur content in the food wastes, implying that during aerobic decomposition considerable portion of sulfur in food wastes would be released into the atmosphere as VOSCs, primarily as DMDS, which is very short-lived in the atmosphere and thus usually less considered in the sources and sinks of reduced sulfur gases.

Acoustic emission studies of posterior stabilized and cruciate retaining knee arthroplasties.

PubMed

Schwarzkopf, Ran; Kummer, Frederick J; Jaffe, William L

2011-09-01

Different acoustic frequencies have been used to diagnose progression of osteoarthritis, gross pathology, and wear in knee prostheses. It is possible that detailed analysis of higher frequencies could detect and quantify the smaller geometric changes (asperities) that develop in articular prosthetic wear. In this study we evaluated the feasibility of using ultrasonic emission to determine total knee arthroplasty (TKA) type and time from implantation using a simple, handheld measurement system. We examined the ultrasound emission generated by similar designs of posterior stabilized (PS) and cruciate retaining (CR) total knee prostheses and native knees of 58 patients and 10 controls. The subjects were asked to sit, rise, sit again, and take five steps while recording the acoustic data from both knees. Acoustic emission analysis examined frequency distributions and power spectrums of the recorded signals, and their relations to prosthesis type and time from implantation. We screened 44 CR and 48 PS TKAs, as well as 24 native knees. Analysis of this data suggested a possibility of differentiating between type of implants, and a relation to time since implantation. Our data suggest that we might be able to assess the status and time from implantation of a TKA by acoustic emission signals. Further in vitro analysis of the relationship of wear to ultrasonic emission data are needed for accurate quantification of arthroplasty wear. A simple, in-office screening tool for TKA patients could indicate which patients require closer follow-up and monitoring due to risk of potential problems.

Anthropogenic Chromium Emissions in China from 1990 to 2009

PubMed Central

Cheng, Hongguang; Zhou, Tan; Li, Qian; Lu, Lu; Lin, Chunye

2014-01-01

An inventory of chromium emission into the atmosphere and water from anthropogenic activities in China was compiled for 1990 through to 2009. We estimate that the total emission of chromium to the atmosphere is about 1.92×105t. Coal and oil combustion were the two leading sources of chromium emission to the atmosphere in China, while the contribution of them showed opposite annual growth trend. In total, nearly 1.34×104t of chromium was discharged to water, mainly from six industrial categories in 20 years. Among them, the metal fabrication industry and the leather tanning sector were the dominant sources of chromium emissions, accounting for approximately 68.0% and 20.0% of the total emissions and representing increases of15.6% and 10.3% annually, respectively. The spatial trends of Cr emissions show significant variation based on emissions from 2005 to 2009. The emission to the atmosphere was heaviest in Hebei, Shandong, Guangdong, Zhejiang and Shanxi, whose annual emissions reached more than 1000t for the high level of coal and oil consumption. In terms of emission to water, the largest contributors were Guangdong, Jiangsu, Shandong and Zhejiang, where most of the leather production and metal manufacturing occur and these four regions accounted for nearly 47.4% of the total emission to water. PMID:24505309

A driving cycle for vehicle emissions estimation in the metropolitan area of Mexico City.

PubMed

Schifter, I; Díaz, L; Rodríguez, R; López-Salinas, E

2005-02-01

A driving cycle derived from driving behavior and real traffic conditions in Mexico City (MC) is proposed. Data acquisition was carried out over diverse MC routes, representing travel under congested and uncongested conditions, using the chase-car approach. Thirteen different on-road patterns, including the four main access roads to MC, trips in both directions and different timetables, a total of 108 trips spanning 1044 km were evaluated in this study. The MC cycle lasts 1360 seconds with a distance of 8.8 km and average speed of 23.4 km h(-1). Both maximum speed (73.6 km h(-1)) and maximum acceleration (2.22 km h(-1)s(-1)) are lower than those of the new vehicles certification employed in Mexico ,FTP-75 cycle., that is, the MC cycle exhibits less cruising time and more transient events than the FTP cycle. A total of 30 light duty gasoline vehicles were classified into different technological groups and tested in an FTP-75 and MC driving cycles in order to compare their emission factors A potential concern is that in Mexico manufacturers design vehicles to meet the emission standards in the FTP, but emission levels increase significantly in a more representative cycle of present driving patterns in the Metropolitan Area of Mexico City (MAMC). The use of a more representative cycle during certification testing, would provide an incentive for vehicle manufacturers to design emissions control systems to remain effective during operation modes that are not currently represented in the official test procedures used in the certification process. Based on the results of the study, the use of MC cycle, which better represents current day driving patterns during testing of vehicle fleets in emissions laboratories, would improve the accuracy of emissions factors used in the MAMC emissions inventories.

On-board measurements of gaseous pollutant emission characteristics under real driving conditions from light-duty diesel vehicles in Chinese cities.

PubMed

Wang, Gang; Cheng, Shuiyuan; Lang, Jianlei; Li, Song; Tian, Liang

2016-08-01

A total of 15 light-duty diesel vehicles (LDDVs) were tested with the goal of understanding the emission factors of real-world vehicles by conducting on-board emission measurements. The emission characteristics of hydrocarbons (HC) and nitrogen oxides (NOx) at different speeds, chemical species profiles and ozone formation potential (OFP) of volatile organic compounds (VOCs) emitted from diesel vehicles with different emission standards were analyzed. The results demonstrated that emission reductions of HC and NOx had been achieved as the control technology became more rigorous from Stage I to Stage IV. It was also found that the HC and NOx emissions and percentage of O2 dropped with the increase of speed, while the percentage of CO2 increased. The abundance of alkanes was significantly higher in diesel vehicle emissions, approximately accounting for 41.1%-45.2%, followed by aromatics and alkenes. The most abundant species were propene, ethane, n-decane, n-undecane, and n-dodecane. The maximum incremental reactivity (MIR) method was adopted to evaluate the contributions of individual VOCs to OFP. The results indicated that the largest contributors to O3 production were alkenes and aromatics, which accounted for 87.7%-91.5%. Propene, ethene, 1,2,4-trimethylbenzene, 1-butene, and 1,2,3-trimethylbenzene were the top five VOC species based on their OFP, and accounted for 54.0%-64.8% of the total OFP. The threshold dilution factor was applied to analyze the possibility of VOC stench pollution. The majority of stench components emitted from vehicle exhaust were aromatics, especially p-diethylbenzene, propylbenzene, m-ethyltoluene, and p-ethyltoluene. Copyright © 2016. Published by Elsevier B.V.

N management of European grasslands: can the exchange of gaseous N species be influenced at the operational level?

PubMed

Calanca, P; Neftel, A; Fuhrer, J

2001-11-30

Grassland ecosystems can be regarded as biochemical reactors in which large amounts of organic nitrogen (N) are converted into inorganic N, and vice versa. If managed in a sustainable manner, grasslands should operate in a quasi steady state, characterized by an almost perfect balance between total N input and output. As a consequence, the exchange of gaseous N species (NH3, NO, NO2, N2O, and N2) between grasslands and the atmosphere is very small compared to the total N turnover. In this study, the effects of two management options (mowing and fertilization) on production and emission of nitrous oxide (N2O) from a grass/clover crop were examined on the basis of observations and model results referring to an experiment carried out on the Swiss Plateau in late summer of 2000. It was found that production and emission of N2O induced by mowing were of the same order of magnitude as those brought about by fertilization, suggesting a possible transfer of N from clover to the soil after defoliation. Emissions were strongly modulated by precipitation on time scales ranging from 1 day to 1 week. This indicates that effective control of N2O emissions through management on a day-to-day basis requires reliable medium-range weather forecasts. Model calculations were not able to reproduce essential characteristics of the emissions. The model slightly overestimated the background emissions, but severely underestimated the emission peaks following fertilizer application, and largely failed to reproduce emission induced by mowing. Shortfalls in the model used for this study were found in relation to the description of soil-water fluxes, soil organic matter, and the physiology of clover.

The Greenhouse Gas Emission from Portland Cement Concrete Pavement Construction in China

PubMed Central

Ma, Feng; Sha, Aimin; Yang, Panpan; Huang, Yue

2016-01-01

This study proposes an inventory analysis method to evaluate the greenhouse gas (GHG) emissions from Portland cement concrete pavement construction, based on a case project in the west of China. The concrete pavement construction process was divided into three phases, namely raw material production, concrete manufacture and pavement onsite construction. The GHG emissions of the three phases are analyzed by a life cycle inventory method. The CO2e is used to indicate the GHG emissions. The results show that for 1 km Portland cement concrete pavement construction, the total CO2e is 8215.31 tons. Based on the evaluation results, the CO2e of the raw material production phase is 7617.27 tons, accounting for 92.7% of the total GHG emissions; the CO2e of the concrete manufacture phase is 598,033.10 kg, accounting for 7.2% of the total GHG emissions. Lastly, the CO2e of the pavement onsite construction phase is 8396.59 kg, accounting for only 0.1% of the total GHG emissions. The main greenhouse gas is CO2 in each phase, which accounts for more than 98% of total emissions. N2O and CH4 emissions are relatively insignificant. PMID:27347987

Reliable and Affordable Control Systems Active Combustor Pattern Factor Control

NASA Technical Reports Server (NTRS)

McCarty, Bob; Tomondi, Chris; McGinley, Ray

2004-01-01

Active, closed-loop control of combustor pattern factor is a cooperative effort between Honeywell (formerly AlliedSignal) Engines and Systems and the NASA Glenn Research Center to reduce emissions and turbine-stator vane temperature variations, thereby enhancing engine performance and life, and reducing direct operating costs. Total fuel flow supplied to the engine is established by the speed/power control, but the distribution to individual atomizers will be controlled by the Active Combustor Pattern Factor Control (ACPFC). This system consist of three major components: multiple, thin-film sensors located on the turbine-stator vanes; fuel-flow modulators for individual atomizers; and control logic and algorithms within the electronic control.

77 FR 44488 - Method 16C for the Determination of Total Reduced Sulfur Emissions From Stationary Sources

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-30

... Method 16C for the Determination of Total Reduced Sulfur Emissions From Stationary Sources AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY: This action promulgates Method 16C for measuring total reduced sulfur (TRS) emissions from stationary sources. Method 16C offers the advantages of...

[Estimation of VOC emission from forests in China based on the volume of tree species].

PubMed

Zhang, Gang-feng; Xie, Shao-dong

2009-10-15

Applying the volume data of dominant trees from statistics on the national forest resources, volatile organic compounds (VOC) emissions of each main tree species in China were estimated based on the light-temperature model put forward by Guenther. China's VOC emission inventory for forest was established, and the space-time and age-class distributions of VOC emission were analyzed. The results show that the total VOC emissions from forests in China are 8565.76 Gg, of which isoprene is 5689.38 Gg (66.42%), monoterpenes is 1343.95 Gg (15.69%), and other VOC is 1532.43 Gg (17.89%). VOC emissions have significant species variation. Quercus is the main species responsible for emission, contributing 45.22% of the total, followed by Picea and Pinus massoniana with 6.34% and 5.22%, respectively. Southwest and Northeast China are the major emission regions. In specific, Yunnan, Sichuan, Heilongjiang, Jilin and Shaanxi are the top five provinces producing the most VOC emissions from forests, and their contributions to the total are 15.09%, 12.58%, 10.35%, 7.49% and 7.37%, respectively. Emissions from these five provinces occupy more than half (52.88%) of the national emissions. Besides, VOC emissions show remarkable seasonal variation. Emissions in summer are the largest, accounting for 56.66% of the annual. Forests of different ages have different emission contribution. Half-mature forests play a key role and contribute 38.84% of the total emission from forests.

Emission Sectoral Contributions of Foreign Emissions to Particulate Matter Concentrations over South Korea

NASA Astrophysics Data System (ADS)

Kim, E.; Kim, S.; Kim, H. C.; Kim, B. U.; Cho, J. H.; Woo, J. H.

2017-12-01

In this study, we investigated the contributions of major emission source categories located upwind of South Korea to Particulate Matter (PM) in South Korea. In general, air quality in South Korea is affected by anthropogenic air pollutants emitted from foreign countries including China. Some studies reported that foreign emissions contributed 50 % of annual surface PM total mass concentrations in the Seoul Metropolitan Area, South Korea in 2014. Previous studies examined PM contributions of foreign emissions from all sectors considering meteorological variations. However, little studies conducted to assess contributions of specific foreign source categories. Therefore, we attempted to estimate sectoral contributions of foreign emissions from China to South Korea PM using our air quality forecasting system. We used Model Inter-Comparison Study in Asia 2010 for foreign emissions and Clean Air Policy Support System 2010 emission inventories for domestic emissions. To quantify contributions of major emission sectors to South Korea PM, we applied the Community Multi-scale Air Quality system with brute force method by perturbing emissions from industrial, residential, fossil-fuel power plants, transportation, and agriculture sectors in China. We noted that industrial sector was pre-dominant over the region except during cold season for primary PMs when residential emissions drastically increase due to heating demand. This study will benefit ensemble air quality forecasting and refined control strategy design by providing quantitative assessment on seasonal contributions of foreign emissions from major source categories.

Global atmospheric emissions of polycyclic aromatic hydrocarbons from 1960 to 2008 and future predictions.

PubMed

Shen, Huizhong; Huang, Ye; Wang, Rong; Zhu, Dan; Li, Wei; Shen, Guofeng; Wang, Bin; Zhang, Yanyan; Chen, Yuanchen; Lu, Yan; Chen, Han; Li, Tongchao; Sun, Kang; Li, Bengang; Liu, Wenxin; Liu, Junfeng; Tao, Shu

2013-06-18

Global atmospheric emissions of 16 polycyclic aromatic hydrocarbons (PAHs) from 69 major sources were estimated for a period from 1960 to 2030. Regression models and a technology split method were used to estimate country and time specific emission factors, resulting in a new estimate of PAH emission factor variation among different countries and over time. PAH emissions in 2007 were spatially resolved to 0.1° × 0.1° grids based on a newly developed global high-resolution fuel combustion inventory (PKU-FUEL-2007). The global total annual atmospheric emission of 16 PAHs in 2007 was 504 Gg (331-818 Gg, as interquartile range), with residential/commercial biomass burning (60.5%), open-field biomass burning (agricultural waste burning, deforestation, and wildfire, 13.6%), and petroleum consumption by on-road motor vehicles (12.8%) as the major sources. South (87 Gg), East (111 Gg), and Southeast Asia (52 Gg) were the regions with the highest PAH emission densities, contributing half of the global total PAH emissions. Among the global total PAH emissions, 6.19% of the emissions were in the form of high molecular weight carcinogenic compounds and the percentage of the carcinogenic PAHs was higher in developing countries (6.22%) than in developed countries (5.73%), due to the differences in energy structures and the disparities of technology. The potential health impact of the PAH emissions was greatest in the parts of the world with high anthropogenic PAH emissions, because of the overlap of the high emissions and high population densities. Global total PAH emissions peaked at 592 Gg in 1995 and declined gradually to 499 Gg in 2008. Total PAH emissions from developed countries peaked at 122 Gg in the early 1970s and decreased to 38 Gg in 2008. Simulation of PAH emissions from 2009 to 2030 revealed that PAH emissions in developed and developing countries would decrease by 46-71% and 48-64%, respectively, based on the six IPCC SRES scenarios.

Global atmospheric emissions of polycyclic aromatic hydrocarbons from 1960 to 2008 and future predictions

PubMed Central

Shen, Huizhong; Huang, Ye; Wang, Rong; Zhu, Dan; Li, Wei; Shen, Guofeng; Wang, Bin; Zhang, Yanyan; Chen, Yuanchen; Lu, Yan; Chen, Han; Li, Tongchao; Sun, Kang; Li, Bengang; Liu, Wenxin; Liu, Junfeng; Tao, Shu

2013-01-01

Global atmospheric emissions of 16 polycyclic aromatic hydrocarbons (PAHs) from 69 major sources were estimated for a period from 1960 to 2030. Regression models and a technology split method were used to estimate country and time specific emission factors, resulting in a new estimate of PAH emission factor variation among different countries and over time. PAH emissions in 2007 were spatially resolved to 0.1°× 0.1° grids based on a newly developed global high-resolution fuel combustion inventory (PKU-FUEL-2007). The global total annual atmospheric emission of 16 PAHs in 2007 was 504 Gg (331-818 Gg, as interquartile range), with residential/commercial biomass burning (60.5%), open-field biomass burning (agricultural waste burning, deforestation, and wildfire, 13.6%), and petroleum consumption by on-road motor vehicles (12.8%) as the major sources. South (87 Gg), East (111 Gg), and Southeast Asia (52 Gg) were the regions with the highest PAH emission densities, contributing half of the global total PAH emissions. Among the global total PAH emissions, 6.19% of the emissions were in the form of high molecular weight carcinogenic compounds and the percentage of the carcinogenic PAHs was higher in developing countries (6.22%) than in developed countries (5.73%), due to the differences in energy structures and the disparities of technology. The potential health impact of the PAH emissions was greatest in the parts of the world with high anthropogenic PAH emissions, because of the overlap of the high emissions and high population densities. Global total PAH emissions peaked at 592 Gg in 1995 and declined gradually to 499 Gg in 2008. Total PAH emissions from developed countries peaked at 122 Gg in the early 1970s and decreased to 38 Gg in 2008. Simulation of PAH emissions from 2009 to 2030 revealed that PAH emissions in developed and developing countries would decrease by 46-71% and 48-64%, respectively, based on the six IPCC SRES scenarios. PMID:23659377

Commercial Aircraft Emission Scenario for 2020: Database Development and Analysis

NASA Technical Reports Server (NTRS)

Sutkus, Donald J., Jr.; Baughcum, Steven L.; DuBois, Douglas P.; Wey, Chowen C. (Technical Monitor)

2003-01-01

This report describes the development of a three-dimensional database of aircraft fuel use and emissions (NO(x), CO, and hydrocarbons) for the commercial aircraft fleet projected to 2020. Global totals of emissions and fuel burn for 2020 are compared to global totals from previous aircraft emission scenario calculations.

A synthesis of carbon dioxide emissions from fossil-fuel combustion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andres, Robert Joseph; Boden, Thomas A; Breon, F.-M.

2012-01-01

This synthesis discusses the emissions of carbon dioxide from fossil-fuel combustion and cement production. While much is known about these emissions, there is still much that is unknown about the details surrounding these emissions. This synthesis explores 5 our knowledge of these emissions in terms of why there is concern about them; how they are calculated; the major global efforts on inventorying them; their global, regional, and national totals at different spatial and temporal scales; how they are distributed on global grids (i.e. maps); how they are transported in models; and the uncertainties associated with these different aspects of themore » emissions. The magnitude of emissions 10 from the combustion of fossil fuels has been almost continuously increasing with time since fossil fuels were first used by humans. Despite events in some nations specifically designed to reduce emissions, or which have had emissions reduction as a byproduct of other events, global total emissions continue their general increase with time. Global total fossil-fuel carbon dioxide emissions are known to within 10% uncertainty (95% 15 confidence interval). Uncertainty on individual national total fossil-fuel carbon dioxide emissions range from a few percent to more than 50 %. The information discussed in this manuscript synthesizes global, regional and national fossil-fuel carbon dioxide emissions, their distributions, their transport, and the associated uncertainties.« less

Diuranl variations and characteristics of organic molecular composition and stable carbon isotope ratios of PM2.5 in Beijing during the "APEC Blue"

NASA Astrophysics Data System (ADS)

Ren, H.; Fan, S.; Fu, P.

2016-12-01

Fine particulate matters (PM2.5) were collected before and during the 2014 Asian-Pacific Economic Cooperation (2014 APEC) (15 October-12 November) in Beijing to study their sources, diurnal variations, and the effects of region controls on the improving of the air quality. Organic molecular compositions of lipids, saccharides, polyacids, ligin & resin products, aromatic acids, phthalate esters, hopanes, PAHs and sterols were analyzed by GC-MS), while stable carbon isotope ratio (δ13C) of total carbon (TC) were determination using Gas Isotope Ratio MS (IRMS, MAT 253). Results indicated that five aerosol episodes were founded before and during the APEC event. Concentrations of most organic compounds showed maxima at nighttime and were obviously decreased during the APEC. These features were associated with meteorological conditions (especially high relative humidity and low wind speed), reginal emission controls (carried out during APEC), urban boundary layer movement and mountain/valley breezes in Beijing. Before the APEC, the main sources of organic aerosols in Beijing were long-range transport from surrounding cities together with local emission sources, while local emissions became the dominant source during the APEC. Biomass burning, motor emissions, fossil fuel combustion such as coal and petroleum, open-burning of municipal wastes during night significantly contributed to organic aerosols in Beijing. Our results suggest that anthropogenic emissions are important sources of aerosols in Beijing, and the regional controls is an efficient way to improve the air quality.

Energy intensity and the energy mix: what works for the environment?

PubMed

El Anshasy, Amany A; Katsaiti, Marina-Selini

2014-04-01

In the absence of carbon sequestration, mitigating carbon emissions can be achieved through a mix of two broad policy approaches: (i) reducing energy intensity by improving energy efficiency and conservation, and (ii) changing the fuel mix. This paper investigates the long-run relationship between energy intensity, the energy mix, and per capita carbon emissions; while controlling for the level of economic activity, the economic structure measured by the relative size of the manufacturing sector, and the differences in institutional qualities across countries. We aim to answer two particularly important policy questions. First, to what extent these policy approaches are effective in mitigating emissions in the long-run? Second, which institutional qualities significantly contribute to better long-run environmental performance? We use historical data for 131 countries in a heterogeneous panel framework for the period 1972-2010. We find that less dependence on fossil fuel and lower energy intensity reduce emissions in the long run. A goal of 10% reduction in CO2 levels in the long-run requires reducing the share of fossil fuel in total energy use by 11%, or reducing energy intensity by 13%. In addition, specific institutional qualities such as better corruption control and judiciary independence contribute to mitigating levels of emissions. Copyright © 2014 Elsevier Ltd. All rights reserved.

The contribution of megacities to regional sulfur pollution in Asia

NASA Astrophysics Data System (ADS)

Guttikunda, Sarath K.; Carmichael, Gregory R.; Calori, Giuseppe; Eck, Christina; Woo, Jung-Hun

Asia is undergoing rapid urbanization resulting in increasing air pollution threats in its cities. The contribution of megacities to sulfur emissions and pollution in Asia is studied over a 25-year period (1975-2000) using a multi-layer Lagrangian puff transport model. Asian megacities cover <2% of the land area but emit ˜16% of the total anthropogenic sulfur emissions of Asia. It is shown that urban sulfur emissions contribute over 30% to the regional pollution levels in large parts of Asia. The average contribution of megacities over the western Pacific increased from <5% in 1975 to >10% in 2000. Two future emission scenarios are evaluated for 2020—"business as usual (BAU)" and "maximum feasible controls (MAXF)" to establish the range of reductions possible for these cities. The MAXF scenario would result in 2020 S-emissions that are ˜80% lower than those in 2000, at an estimated control cost of US 87 billion per year (1995 US) for all of Asia. An urban scale analysis of sulfur pollution for four megacities—Shanghai, and Chongqing in China; Seoul in South Korea; and Mumbai (formerly Bombay) in India is presented. If pollution levels were allowed to increase under BAU, over 30 million people in these cities alone would be exposed to levels in excess of the WHO guidelines.

A modeling study of the nonlinear response of fine particles to air pollutant emissions in the Beijing-Tianjin-Hebei region

NASA Astrophysics Data System (ADS)

Zhao, Bin; Wu, Wenjing; Wang, Shuxiao; Xing, Jia; Chang, Xing; Liou, Kuo-Nan; Jiang, Jonathan H.; Gu, Yu; Jang, Carey; Fu, Joshua S.; Zhu, Yun; Wang, Jiandong; Lin, Yan; Hao, Jiming

2017-10-01

The Beijing-Tianjin-Hebei (BTH) region has been suffering from the most severe fine-particle (PM2. 5) pollution in China, which causes serious health damage and economic loss. Quantifying the source contributions to PM2. 5 concentrations has been a challenging task because of the complicated nonlinear relationships between PM2. 5 concentrations and emissions of multiple pollutants from multiple spatial regions and economic sectors. In this study, we use the extended response surface modeling (ERSM) technique to investigate the nonlinear response of PM2. 5 concentrations to emissions of multiple pollutants from different regions and sectors over the BTH region, based on over 1000 simulations by a chemical transport model (CTM). The ERSM-predicted PM2. 5 concentrations agree well with independent CTM simulations, with correlation coefficients larger than 0.99 and mean normalized errors less than 1 %. Using the ERSM technique, we find that, among all air pollutants, primary inorganic PM2. 5 makes the largest contribution (24-36 %) to PM2. 5 concentrations. The contribution of primary inorganic PM2. 5 emissions is especially high in heavily polluted winter and is dominated by the industry as well as residential and commercial sectors, which should be prioritized in PM2. 5 control strategies. The total contributions of all precursors (nitrogen oxides, NOx; sulfur dioxides, SO2; ammonia, NH3; non-methane volatile organic compounds, NMVOCs; intermediate-volatility organic compounds, IVOCs; primary organic aerosol, POA) to PM2. 5 concentrations range between 31 and 48 %. Among these precursors, PM2. 5 concentrations are primarily sensitive to the emissions of NH3, NMVOC + IVOC, and POA. The sensitivities increase substantially for NH3 and NOx and decrease slightly for POA and NMVOC + IVOC with the increase in the emission reduction ratio, which illustrates the nonlinear relationships between precursor emissions and PM2. 5 concentrations. The contributions of primary inorganic PM2. 5 emissions to PM2. 5 concentrations are dominated by local emission sources, which account for over 75 % of the total primary inorganic PM2. 5 contributions. For precursors, however, emissions from other regions could play similar roles to local emission sources in the summer and over the northern part of BTH. The source contribution features for various types of heavy-pollution episodes are distinctly different from each other and from the monthly mean results, illustrating that control strategies should be differentiated based on the major contributing sources during different types of episodes.

Performance of Charcoal Cookstoves for Haiti, Part 2: Results from the Controlled Cooking Test

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lask, Kathleen; Jones, Jennifer; Booker, Kayje

2011-11-30

Five charcoal cookstoves were tested using a Controlled Cooking Test (CCT) developed from cooking practices in Haiti. Cookstoves were tested for total burn time, specific fuel consumption, and emissions of carbon monoxide (CO), carbon dioxide (CO 2), and the ratio of carbon monoxide to carbon dioxide (CO/CO 2). These results are presented in this report along with LBNL testers’ observations regarding the usability of the stoves.

Effects of agriculture upon the air quality and climate: research, policy, and regulations.

PubMed

Aneja, Viney P; Schlesinger, William H; Erisman, Jan Willem

2009-06-15

Scientific assessments of agricultural air quality, including estimates of emissions and potential sequestration of greenhouse gases, are an important emerging area of environmental science that offers significant challenges to policy and regulatory authorities. Improvements are needed in measurements, modeling, emission controls, and farm operation management. Controlling emissions of gases and particulate matter from agriculture is notoriously difficult as this sector affects the most basic need of humans, i.e., food. Current policies combine an inadequate science covering a very disparate range of activities in a complex industry with social and political overlays. Moreover, agricultural emissions derive from both area and point sources. In the United States, agricultural emissions play an important role in several atmospherically mediated processes of environmental and public health concerns. These atmospheric processes affect local and regional environmental quality, including odor, particulate matter (PM) exposure, eutrophication, acidification, exposure to toxics, climate, and pathogens. Agricultural emissions also contribute to the global problems caused by greenhouse gas emissions. Agricultural emissions are variable in space and time and in how they interact within the various processes and media affected. Most important in the U.S. are ammonia (where agriculture accounts for approximately 90% of total emissions), reduced sulfur (unquantified), PM25 (approximately 16%), PM110 (approximately 18%), methane (approximately 29%), nitrous oxide (approximately 72%), and odor and emissions of pathogens (both unquantified). Agriculture also consumes fossil fuels for fertilizer production and farm operations, thus emitting carbon dioxide (CO2), oxides of nitrogen (NO(x)), sulfur oxides (SO(x)), and particulates. Current research priorities include the quantification of point and nonpoint sources, the biosphere-atmosphere exchange of ammonia, reduced sulfur compounds, volatile organic compounds, greenhouse gases, odor and pathogens, the quantification of landscape processes, and the primary and secondary emissions of PM. Given the serious concerns raised regarding the amount and the impacts of agricultural air emissions, policies must be pursued and regulations must be enacted in orderto make real progress in reducing these emissions and their associated environmental impacts.

PROCEEDINGS ON SYNCHROTRON RADIATION: Transfer characterization of sulfur from coal-burning emission to plant leaves by PIXE and XANES

NASA Astrophysics Data System (ADS)

Bao, Liang-Man; Zhang, Gui-Lin; Zhang, Yuan-Xim; Li, Yan; Lin, Jun; Liu, Wei; Cao, Qing-Chen; Zhao, Yi-Dong; Ma, Chen-Yan; Han, Yong

2009-11-01

The impact of coal-burning emission on sulfur in camphor leaves was investigated using Proton Induced X-ray Emission (PIXE) and synchrotron radiation technique X-ray Absorption Near-Edge Structure (XANES) spectroscopy. The PIXE results show that the sulfur concentrations in the leaves collected at the polluted site are significantly higher than those in controls. The Sulfur XANES spectra show the presence of organic (disulfides, thiols, thioethers, sulfonates and sulfoxides) and inorganic sulfur (sulfates) in the leaves. The inorganic sulfur in the leaves of camphor tree polluted by coal combustion is 15% more than that of the control site. The results suggest that the long-term coal-burning pollution resulted in an enhanced content of the total sulfur and sulfate in the leaves, and the uptake of sulfur by leaves had exceeded the metabolic requirement of plants and the excess of sulfur was stored as SO2-4. It can monitor the sulfur pollution in atmosphere.

Improving the City-scale Emission Inventory of Anthropogenic Air Pollutants: A Case Study of Nanjing

NASA Astrophysics Data System (ADS)

Qiu, L.; Zhao, Y.; Xu, R.; Xie, F.; Wang, H.; Qin, H.; Wu, X.; Zhang, J.

2014-12-01

To evaluate the improvement of city-scale emission inventory, a high-resolution emission inventory of air pollutants for Nanjing is first developed combining detailed source information, and then justified through quantitative analysis with observations. The best available domestic emission factors and unit-/facility-based activity level data were compiled based on a thorough field survey on major emission sources. Totally 1089 individual emission sources were identified as point sources and all the emission-related parameters including burner type, combustion technology, fuel quality, and removal efficiency of pollution control devices, are carefully investigated and analyzed. Some new data such as detailed information of city fueling-gas stations, construction sites, monthly activity level, data from continuous emission monitoring systems and traffic flow information were combined to improve spatiotemporal distribution of this inventory. For SO2, NOX and CO, good spatial correlations were found between ground observation (9 state controlling air sampling sites in Nanjing) and city-scale emission inventory (R2=0.34, 0.38 and 0.74, respectively). For TSP, PM10 and PM2.5, however, poorer correlation was found due to relatively weaker accuracy in emission estimation and spatial distribution of road dust. The mixing ratios between specific pollutants including OC/EC, BC/CO and CO2/CO, are well correlated between those from ground observation and emission. Compared to MEIC (Multi-resolution Emission Inventory for China), there is a better spatial consistence between this city-scale emission inventory and NO2 measured by OMI (Ozone Monitoring Instrument). In particular, the city-scale emission inventory still correlated well with satellite observations (R2=0.28) while the regional emission inventory showed little correlation with satellite observations (R2=0.09) when grids containing power plants are excluded. It thus confirms the improvement of city-scale emission inventory on industrial and transportation sources other than big power plants. Through the inventory evaluation, the necessity to develop high-resolution emission inventory with comprehensive emission source information is revealed for atmospheric science studies and air quality improvement at local scale.

Diurnal variation of CO2, CH4, and N2O emission fluxes continuously monitored in-situ in three environmental habitats in a subtropical estuarine wetland.

PubMed

Yang, Wen-Bin; Yuan, Chung-Shin; Tong, Chuan; Yang, Pin; Yang, Lei; Huang, Bang-Qin

2017-06-15

Wetlands play a crucial role in modulating atmospheric concentrations of greenhouse gases (GHGs) such as carbon dioxide (CO 2 ), methane (CH 4 ), and nitrous oxide (N 2 O). The key factors controlling GHG emission from subtropical estuarine wetlands were investigated in this study, which continuously monitored the uptake/emission of GHGs (CO 2 , CH 4 , and N 2 O) by/from a subtropical estuarine wetland located in the Minjiang estuary in the coastal region of southeastern China. A self-designed floating chamber was used to collect air samples on-site at three environmental habitats (Phragmites australis marsh, mudflats, and river water). The CO 2 , CH 4 , and N 2 O concentrations were then measured using an automated nondispersive infrared analyzer. The magnitudes of the CO 2 and N 2 O emission fluxes at the three habitats were ordered as river water>P. australis>mudflats. P. australis emitted GHGs through photosynthesis and respiration processes. Emissions of CH 4 from P. australis and the mudflats were revealed to be slightly higher than those from the river water. The total GHG emission fluxes at the three environmental habitats were quite similar (4.68-4.78gm -2 h -1 ). However, when the total carbon dioxide equivalent fluxes (CO 2 -e) were considered, the river water was discovered to emit the most CO 2 -e compared with P. australis and the mudflats. Based on its potential to increase global warming, N 2 O was the main contributor to the total GHG emission, with that emitted from the river water being the most considerable. Tidal water carried onto the marsh had its own GHG content and thus has acted as a source or sink of GHGs. However, water quality had a large effect on GHG emissions from the river water whereas the tidal water height did not. Both high salinity and large amounts of sulfates in the wetlands explicitly inhibited the activity of CH 4 -producing bacteria, particularly at nighttime. Copyright © 2017 Elsevier Ltd. All rights reserved.

Decadal changes in emissions of volatile organic compounds (VOCs) from on-road vehicles with intensified automobile pollution control: Case study in a busy urban tunnel in south China.

PubMed

Zhang, Yanli; Yang, Weiqiang; Simpson, Isobel; Huang, Xinyu; Yu, Jianzhen; Huang, Zhonghui; Wang, Zhaoyi; Zhang, Zhou; Liu, Di; Huang, Zuzhao; Wang, Yujun; Pei, Chenglei; Shao, Min; Blake, Donald R; Zheng, Junyu; Huang, Zhijiong; Wang, Xinming

2018-02-01

In the efforts at controlling automobile emissions, it is important to know in what extent air pollutants from on-road vehicles could be truly reduced. In 2014 we conducted tests in a heavily trafficked tunnel in south China to characterize emissions of volatile organic compounds (VOC) from on-road vehicle fleet and compared our results with those obtained in the same tunnel in 2004. Alkanes, aromatics, and alkenes had average emission factors (EFs) of 338, 63, and 42 mg km -1 in 2014 against that of 194, 129, and 160 mg km -1 in 2004, respectively. In 2014, LPG-related propane, n-butane and i-butane were the top three non-methane hydrocarbons (NMHCs) with EFs of 184 ± 21, 53 ± 6 and 31 ± 3 mg km -1 ; the gasoline evaporation marker i-pentane had an average EF of 17 ± 3 mg km -1 ; ethylene and propene were the top two alkenes with average EFs of 16 ± 1 and 9.7 ± 0.9 mg km -1 , respectively; isoprene had no direct emission from vehicles; toluene showed the highest EF of 11 ± 2 mg km -1 among the aromatics; and acetylene had an average EF of 7 ± 1 mg km -1 . While EFs of total NMHCs decreased only 9% from 493 ± 120 mg km -1 in 2004 to 449 ± 40 mg km -1 in 2014, their total ozone formation potential (OFP) decreased by 57% from 2.50 × 10 3  mg km -1 in 2004 to 1.10 × 10 3  mg km -1 in 2014, and their total secondary organic aerosol formation potential (SOAFP) decreased by 50% from 50 mg km -1 in 2004 to 25 mg km -1 in 2014. The large drop in ozone and SOA formation potentials could be explained by reduced emissions of reactive alkenes and aromatics, due largely to fuel transition from gasoline/diesel to LPG for taxis/buses and upgraded vehicle emission standards. Copyright © 2017 Elsevier Ltd. All rights reserved.

Feedback control of the lower hybrid power deposition profile on Tore Supra

NASA Astrophysics Data System (ADS)

Barana, O.; Mazon, D.; Laborde, L.; Turco, F.

2007-07-01

The Tore Supra facility is well suited to study ITER relevant topics such as the real-time control of plasma current and the sustaining of steady-state discharges. This work describes a tool that was recently developed and implemented on Tore Supra to control in real time, by means of the direct knowledge of the suprathermal electron local emission profile, the width of the lower hybrid power deposition profile. This quantity can be considered to some extent equivalent to the width of the plasma current density profile in case of fully non-inductive discharges. This system takes advantage of an accurate hard x-ray diagnostics, of an efficient lower hybrid additional heating and of a reliable real-time communication network. The successful experiments carried out to test the system employed, as actuators, the parallel refractive index n// and the total power PLH. The control of the suprathermal electron local emission profile through n// was also integrated with the feedback control of the total plasma current IP with PLH and of the loop voltage Vloop with the central solenoid flux. These results demonstrate that the system is robust, reliable and able to counterbalance destabilizing events. This tool can be effectively used in the future in fully non-inductive discharges to improve the MHD stability and to maintain internal transport barriers or lower hybrid enhanced performance modes. The real-time control of the lower hybrid power deposition profile could also be used in conjunction with the electron-cyclotron radiofrequency heating for synergy studies.

Bacterial pathogen indicators regrowth and reduced sulphur compounds' emissions during storage of electro-dewatered biosolids.

PubMed

Navab-Daneshmand, Tala; Enayet, Samia; Gehr, Ronald; Frigon, Dominic

2014-10-01

Electro-dewatering (ED) increases biosolids dryness from 10-15 to 30-50%, which helps wastewater treatment facilities control disposal costs. Previous work showed that high temperatures due to Joule heating during ED inactivate total coliforms to meet USEPA Class A biosolids requirements. This allows biosolids land application if the requirements are still met after the storage period between production and application. In this study, we examined bacterial regrowth and odour emissions during the storage of ED biosolids. No regrowth of total coliforms was observed in ED biosolids over 7d under aerobic or anaerobic incubations. To mimic on-site contamination during storage or transport, ED samples were seeded with untreated sludge. Total coliform counts decreased to detection limits after 4d in inoculated samples. Olfactometric analysis of ED biosolids odours showed that odour concentrations were lower compared to the untreated and heat-treated control biosolids. Furthermore, under anaerobic conditions, odorous reduced sulphur compounds (methanethiol, dimethyl sulphide and dimethyl disulphide) were produced by untreated and heat-treated biosolids, but were not detected in the headspaces above ED samples. The data demonstrate that ED provides advantages not only as a dewatering technique, but also for producing biosolids with lower microbial counts and odour levels. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

... Service Valve 1 6.42 Connector 5.71 Open-Ended Line 11.27 Pressure Relief Valve 2.01 Meter 2.93 Population... Pneumatic Device Vents 2 18.20 Intermittent Bleed Pneumatic Device Vents 2 2.35 1 Valves include control...

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

... Service Valve 1 6.42 Connector 5.71 Open-Ended Line 11.27 Pressure Relief Valve 2.01 Meter 2.93 Population... Pneumatic Device Vents 2 18.20 Intermittent Bleed Pneumatic Device Vents 2 2.35 1 Valves include control...

40 CFR 52.1173 - Control strategy: Particulates.

Code of Federal Regulations, 2014 CFR

2014-07-01

... on the quantity of total dissolved solids in the quench water. (12) The State adopts and submits... establishes 2023 motor vehicle emissions budgets for the Detroit-Ann Arbor area of 4,360 tpy for primary PM2.5...), has been approved as submitted on July 5, 2011. The maintenance plan establishes 2023 motor vehicle...

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2010-02-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Mercury emission and speciation of coal-fired power plants in China

NASA Astrophysics Data System (ADS)

Wang, S.; Zhang, L.; Li, G.; Wu, Y.; Hao, J.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

2009-11-01

Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of selective catalyst reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

Air pollution control and decreasing new particle formation lead to strong climate warming

NASA Astrophysics Data System (ADS)

Makkonen, R.; Asmi, A.; Kerminen, V.-M.; Boy, M.; Arneth, A.; Hari, P.; Kulmala, M.

2012-02-01

The number concentration of cloud droplets determines several climatically relevant cloud properties. A major cause for the high uncertainty in the indirect aerosol forcing is the availability of cloud condensation nuclei (CCN), which in turn is highly sensitive to atmospheric new particle formation. Here we present the effect of new particle formation on anthropogenic aerosol forcing in present-day (year 2000) and future (year 2100) conditions. The present-day total aerosol forcing is increased from -1.0 W m-2 to -1.6 W m-2 when nucleation is introduced into the model. Nucleation doubles the change in aerosol forcing between years 2000 and 2100, from +0.6 W m-2 to +1.4 W m-2. Two climate feedbacks are studied, resulting in additional negative forcings of -0.1 W m-2 (+10% DMS emissions in year 2100) and -0.5 W m-2 (+50% BVOC emissions in year 2100). With the total aerosol forcing diminishing in response to air pollution control measures taking effect, warming from increased greenhouse gas concentrations can potentially increase at a very rapid rate.

Nitrate but not tea saponin feed additives decreased enteric methane emissions in nonlactating cows.

PubMed

Guyader, J; Eugène, M; Doreau, M; Morgavi, D P; Gérard, C; Loncke, C; Martin, C

2015-11-01

Tea saponin is considered a promising natural compound for reducing enteric methane emissions in ruminants. A trial was conducted to study the effect of this plant extract fed alone or in combination with nitrate on methane emissions, total tract digestive processes, and ruminal characteristics in cattle. The experiment was conducted as a 2 × 2 factorial design with 4 ruminally cannulated nonlactating dairy cows. Feed offer was restricted to 90% of voluntary intake and diets consisted of (DM basis): 1) control (CON; 50% hay and 50% pelleted concentrates), 2) CON with 0.5% tea saponin (TEA), 3) CON with 2.3% nitrate (NIT), and 4) CON with 0.5% tea saponin and 2.3% nitrate (TEA+NIT). Tea saponin and nitrate were included in pelleted concentrates. Diets contained similar amounts of CP (12.2%), starch (26.0%), and NDF (40.1%). Experimental periods lasted 5 wk including 2 wk of measurement (wk 4 and 5), during which intake was measured daily. In wk 4, daily methane emissions were quantified for 4 d using open circuit respiratory chambers. In wk 5, total tract digestibility, N balance, and urinary excretion of purine derivatives were determined from total feces and urine collected separately for 6 d. Ruminal fermentation products and protozoa concentration were analyzed from samples taken after morning feeding for 2 nonconsecutive days in wk 5. Tea saponin and nitrate supplementation decreased feed intake ( < 0.05), with an additive effect when fed in combination. Compared with CON, tea saponin did not modify methane emissions (g/kg DMI; > 0.05), whereas nitrate-containing diets (NIT and TEA+NIT) decreased methanogenesis by 28%, on average ( < 0.001). Total tract digestibility, N balance, and urinary excretion of purine derivatives were similar among diets. Ruminal fermentation products were not affected by tea saponin, whereas nitrate-containing diets increased acetate proportion and decreased butyrate proportion and ammonia concentration ( < 0.05). Under the experimental conditions tested, we confirmed the antimethanogenic effect of nitrate, whereas tea saponin alone included in pelleted concentrates failed to decrease enteric methane emissions in nonlactating dairy cows.

An Emission Inventory of Polycyclic Aromatic Hydrocarbons in China

NASA Astrophysics Data System (ADS)

Mu, Xilong; Zhu, Xianlei; Wang, Xuesong

2015-04-01

Polycyclic Aromatic Hydrocarbons (PAHs) are among the most dangerous compounds due to their high carcinogenic and mutagenic character. Emission inventory provides the primary data to account for the sources of ambient PAHs and server as a necessary database for effective PAHs pollution control. China is experiencing fast economic growth and large energy consumption, which might result in a large amount of PAHs anthropogenic emissions. Therefore, based on the previous studies and combined recently field emission measurements as well as socio-economic activity data, the development of a nationwide PAHs emission inventory is needed. In this work, the emission inventory of 16 PAHs listed as U.S. Environmental Protection Agency priority pollutants in China in the year 2012 is compiled. The emission amounts of PAHs were estimated as annual rates of emission-related activities multiplied by respective emission factors. The activities such as fuel consumption, including fossil fuel and biofuel, and socio-economic statistics were obtained from yearbook released by Chinese central government and/or provincial governments, as well as related industry reports. Emission factors were derived from the related literature. Recently reported emission factors from local measurements were used. The total emissions of PAHs were 120611 ton in 2012. In China, PAHs were emitted predominantly from domestic combustion of coal and biofuel, coking industry and motor vehicles, accounting for 72% of the total amount. PAHs emission profiles were significantly different between China and the other countries. The emission profile in China featured a relatively higher portion of high molecular weight species with carcinogenic potential due to large contributions of domestic combustion and coking industry. Domestic combustion of straw, coal and firewood emitted 19464 ton, 8831 ton, and 5062 ton of PAHs, respectively, which were much higher than those in other countries. Emission per capita showed geographical variations. In general, the southeastern provinces of China were characterized by higher emission per capita. The PAHs emissions were higher in the winter than those in the summer. In the following work, the above emission inventory will be used as an input to Chemical Transport Model to simulate the ambient PAHs concentrations in China, and the uncertainty of the inventory will be assessed based on the comparisons between simulated concentrations and available observations. Acknowledgement This work was financially supported by the Natural Science Foundation of China (Grant No. 41175102). Corresponding author: Xuesong Wang

Climate responses to anthropogenic emissions of short-lived climate pollutants

NASA Astrophysics Data System (ADS)

Baker, L. H.; Collins, W. J.; Olivié, D. J. L.; Cherian, R.; Hodnebrog, Ø.; Myhre, G.; Quaas, J.

2015-07-01

Policies to control air quality focus on mitigating emissions of aerosols and their precursors, and other short-lived climate pollutants (SLCPs). On a local scale, these policies will have beneficial impacts on health and crop yields, by reducing particulate matter (PM) and surface ozone concentrations; however, the climate impacts of reducing emissions of SLCPs are less straightforward to predict. In this paper we consider a set of idealized, extreme mitigation strategies, in which the total anthropogenic emissions of individual SLCP emissions species are removed. This provides an upper bound on the potential climate impacts of such air quality strategies. We focus on evaluating the climate responses to changes in anthropogenic emissions of aerosol precursor species: black carbon (BC), organic carbon (OC) and sulphur dioxide (SO2). We perform climate integrations with four fully coupled atmosphere-ocean global climate models (AOGCMs), and examine the effects on global and regional climate of removing the total land-based anthropogenic emissions of each of the three aerosol precursor species. We find that the SO2 emissions reductions lead to the strongest response, with all models showing an increase in surface temperature focussed in the Northern Hemisphere mid and (especially) high latitudes, and showing a corresponding increase in global mean precipitation. Changes in precipitation patterns are driven mostly by a northward shift in the ITCZ (Intertropical Convergence Zone), consistent with the hemispherically asymmetric warming pattern driven by the emissions changes. The BC and OC emissions reductions give a much weaker response, and there is some disagreement between models in the sign of the climate responses to these perturbations. These differences between models are due largely to natural variability in sea-ice extent, circulation patterns and cloud changes. This large natural variability component to the signal when the ocean circulation and sea-ice are free-running means that the BC and OC mitigation measures do not necessarily lead to a discernible climate response.

Climate responses to anthropogenic emissions of short-lived climate pollutants

NASA Astrophysics Data System (ADS)

Baker, L. H.; Collins, W. J.; Olivié, D. J. L.; Cherian, R.; Hodnebrog, Ø.; Myhre, G.; Quaas, J.; Samset, B. H.

2015-02-01

Policies to control air quality focus on mitigating emissions of aerosols and their precursors, and other short-lived climate pollutants (SLCPs). On a local scale, these policies will have beneficial impacts on health and crop yields, by reducing particulate matter (PM) and surface ozone concentrations; however, the climate impacts of reducing emissions of SLCPs are less straightforward to predict. In this paper we consider a set of idealised, extreme mitigation strategies, in which the total anthropogenic emissions of individual SLCP emissions species are removed. This provides an upper bound on the potential climate impacts of such air quality strategies. We focus on evaluating the climate responses to changes in anthropogenic emissions of aerosol precursor species: black carbon (BC), organic carbon (OC) and sulphur dioxide (SO2). We perform climate integrations with four fully coupled atmosphere-ocean global climate models (AOGCMs), and examine the effects on global and regional climate of removing the total land-based anthropogenic emissions of each of the three aerosol precursor species. We find that the SO2 emissions reductions lead to the strongest response, with all three models showing an increase in surface temperature focussed in the northern hemisphere high latitudes, and a corresponding increase in global mean precipitation and run-off. Changes in precipitation and run-off patterns are driven mostly by a northward shift in the ITCZ, consistent with the hemispherically asymmetric warming pattern driven by the emissions changes. The BC and OC emissions reductions give a much weaker forcing signal, and there is some disagreement between models in the sign of the climate responses to these perturbations. These differences between models are due largely to natural variability in sea-ice extent, circulation patterns and cloud changes. This large natural variability component to the signal when the ocean circulation and sea-ice are free-running means that the BC and OC mitigation measures do not necessarily lead to a discernible climate response.

A model for inventory of ammonia emissions from agriculture in the Netherlands

NASA Astrophysics Data System (ADS)

Velthof, G. L.; van Bruggen, C.; Groenestein, C. M.; de Haan, B. J.; Hoogeveen, M. W.; Huijsmans, J. F. M.

2012-01-01

Agriculture is the major source of ammonia (NH 3). Methodologies are needed to quantify national NH 3 emissions and to identify the most effective options to mitigate NH 3 emissions. Generally, NH 3 emissions from agriculture are quantified using a nitrogen (N) flow approach, in which the NH 3 emission is calculated from the N flows and NH 3 emission factors. Because of the direct dependency between NH 3 volatilization and Total Ammoniacal N (TAN; ammonium-N + N compounds readily broken down to ammonium) an approach based on TAN is preferred to calculate NH 3 emission instead of an approach based on total N. A TAN-based NH 3-inventory model was developed, called NEMA (National Emission Model for Ammonia). The total N excretion and the fraction of TAN in the excreted N are calculated from the feed composition and N digestibility of the components. TAN-based emission factors were derived or updated for housing systems, manure storage outside housing, manure application techniques, N fertilizer types, and grazing. The NEMA results show that the total NH 3 emission from agriculture in the Netherlands in 2009 was 88.8 Gg NH 3-N, of which 50% from housing, 37% from manure application, 9% from mineral N fertilizer, 3% from outside manure storage, and 1% from grazing. Cattle farming was the dominant source of NH 3 in the Netherlands (about 50% of the total NH 3 emission). The NH 3 emission expressed as percentage of the excreted N was 22% of the excreted N for poultry, 20% for pigs, 15% for cattle, and 12% for other livestock, which is mainly related to differences in emissions from housing systems. The calculated ammonia emission was most sensitive to changes in the fraction of TAN in the excreted manure and to the emission factor of manure application. From 2011, NEMA will be used as official methodology to calculate the national NH 3 emission from agriculture in the Netherlands.