40 CFR 86.1811-01 - Emission standards for light-duty vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1814-02 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1812-01 - Emission standards for light-duty trucks 1.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1815-01 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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 86.1815-01 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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 86.1814-01 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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 86.1813-01 - Emission standards for light-duty trucks 2.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1811-01 - Emission standards for light-duty vehicles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1811-01 - Emission standards for light-duty vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1814-01 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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 86.1814-02 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1812-01 - Emission standards for light-duty trucks 1.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1815-02 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1814-02 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1814-01 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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 86.1812-01 - Emission standards for light-duty trucks 1.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1813-01 - Emission standards for light-duty trucks 2.

Code of Federal Regulations, 2013 CFR

2013-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1815-02 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1814-02 - Emission standards for light-duty trucks 3.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1811-01 - Emission standards for light-duty vehicles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1815-02 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. This... (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 86.1815-01 - Emission standards for light-duty trucks 4.

Code of Federal Regulations, 2012 CFR

2012-07-01

... equivalents and references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a... (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...

Environmental Consequences of Invasive Species: Greenhouse Gas Emissions of Insecticide Use and the Role of Biological Control in Reducing Emissions

PubMed Central

Heimpel, George E.; Yang, Yi; Hill, Jason D.; Ragsdale, David W.

2013-01-01

Greenhouse gas emissions associated with pesticide applications against invasive species constitute an environmental cost of species invasions that has remained largely unrecognized. Here we calculate greenhouse gas emissions associated with the invasion of an agricultural pest from Asia to North America. The soybean aphid, Aphis glycines, was first discovered in North America in 2000, and has led to a substantial increase in insecticide use in soybeans. We estimate that the manufacture, transport, and application of insecticides against soybean aphid results in approximately 10.6 kg of carbon dioxide (CO2) equivalent greenhouse gasses being emitted per hectare of soybeans treated. Given the acreage sprayed, this has led to annual emissions of between 6 and 40 million kg of CO2 equivalent greenhouse gasses in the United States since the invasion of soybean aphid, depending on pest population size. Emissions would be higher were it not for the development of a threshold aphid density below which farmers are advised not to spray. Without a threshold, farmers tend to spray preemptively and the threshold allows farmers to take advantage of naturally occurring biological control of the soybean aphid, which can be substantial. We find that adoption of the soybean aphid economic threshold can lead to emission reductions of approximately 300 million kg of CO2 equivalent greenhouse gases per year in the United States. Previous studies have documented that biological control agents such as lady beetles are capable of suppressing aphid densities below this threshold in over half of the soybean acreage in the U.S. Given the acreages involved this suggests that biological control results in annual emission reductions of over 200 million kg of CO2 equivalents. These analyses show how interactions between invasive species and organisms that suppress them can interact to affect greenhouse gas emissions. PMID:23977273

Environmental consequences of invasive species: greenhouse gas emissions of insecticide use and the role of biological control in reducing emissions.

PubMed

Heimpel, George E; Yang, Yi; Hill, Jason D; Ragsdale, David W

2013-01-01

Greenhouse gas emissions associated with pesticide applications against invasive species constitute an environmental cost of species invasions that has remained largely unrecognized. Here we calculate greenhouse gas emissions associated with the invasion of an agricultural pest from Asia to North America. The soybean aphid, Aphis glycines, was first discovered in North America in 2000, and has led to a substantial increase in insecticide use in soybeans. We estimate that the manufacture, transport, and application of insecticides against soybean aphid results in approximately 10.6 kg of carbon dioxide (CO2) equivalent greenhouse gasses being emitted per hectare of soybeans treated. Given the acreage sprayed, this has led to annual emissions of between 6 and 40 million kg of CO2 equivalent greenhouse gasses in the United States since the invasion of soybean aphid, depending on pest population size. Emissions would be higher were it not for the development of a threshold aphid density below which farmers are advised not to spray. Without a threshold, farmers tend to spray preemptively and the threshold allows farmers to take advantage of naturally occurring biological control of the soybean aphid, which can be substantial. We find that adoption of the soybean aphid economic threshold can lead to emission reductions of approximately 300 million kg of CO2 equivalent greenhouse gases per year in the United States. Previous studies have documented that biological control agents such as lady beetles are capable of suppressing aphid densities below this threshold in over half of the soybean acreage in the U.S. Given the acreages involved this suggests that biological control results in annual emission reductions of over 200 million kg of CO2 equivalents. These analyses show how interactions between invasive species and organisms that suppress them can interact to affect greenhouse gas emissions.

40 CFR 86.1816-05 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a) Exhaust emission... (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 86.1816-05 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a) Exhaust emission... (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 86.1816-05 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a) Exhaust emission... (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 86.1816-05 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... references to non-methane hydrocarbons shall mean non-methane hydrocarbon equivalents. (a) Exhaust emission... (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 86.1816-05 - Emission standards for complete heavy-duty vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

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

Final Rule for Control of Emissions From New Marine Compression-Ignition Engines at or Above 2.5 Liters Per Cylinder

EPA Pesticide Factsheets

The near-term, Tier 1 standards in this rule are equivalent to the internationally negotiated emission limits for oxides of nitrogen (NOx). These standards will go into effect in 2004 and are based on readily available emission-control technology.

40 CFR 86.005-10 - Emission standards for 2005 and later model year Otto-cycle heavy-duty engines and vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... megajoule). (B) Oxides of Nitrogen plus Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines fueled... Nitrogen plus Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines fueled with methanol. 1.5 grams... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW...

40 CFR 86.005-10 - Emission standards for 2005 and later model year Otto-cycle heavy-duty engines and vehicles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines fueled with methanol. 1.0 grams per... megajoule). (ii) Oxides of Nitrogen plus Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW...

40 CFR 86.005-10 - Emission standards for 2005 and later model year Otto-cycle heavy-duty engines and vehicles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines fueled with methanol. 1.0 grams per... megajoule). (ii) Oxides of Nitrogen plus Non-methane Hydrocarbon Equivalent (NO X + NMHCE) for engines... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW...

40 CFR 63.1335 - General recordkeeping and reporting provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Precompliance Report. The Administrator may deem alternative controls to be equivalent to the controls required... (CONTINUED) National Emission Standards for Hazardous Air Pollutant Emissions: Group IV Polymers and Resins... malfunction and a program for corrective action for malfunctioning process and air pollution control equipment...

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.

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...

40 CFR 52.1488 - Visibility protection.

Code of Federal Regulations, 2011 CFR

2011-07-01

... substituting equivalent or superior control technology, provided such technology meets applicable emission... operator shall meet the following deadlines for design and construction of the emission control equipment... binding contract to design the SO2, opacity and NOX control systems for Unit 1 and Unit 2 by March 1, 2003...

40 CFR 52.1488 - Visibility protection.

Code of Federal Regulations, 2012 CFR

2012-07-01

... substituting equivalent or superior control technology, provided such technology meets applicable emission... operator shall meet the following deadlines for design and construction of the emission control equipment... binding contract to design the SO2, opacity and NOX control systems for Unit 1 and Unit 2 by March 1, 2003...

40 CFR 52.1488 - Visibility protection.

Code of Federal Regulations, 2013 CFR

2013-07-01

... substituting equivalent or superior control technology, provided such technology meets applicable emission... operator shall meet the following deadlines for design and construction of the emission control equipment... binding contract to design the SO2, opacity and NOX control systems for Unit 1 and Unit 2 by March 1, 2003...

40 CFR 52.1488 - Visibility protection.

Code of Federal Regulations, 2010 CFR

2010-07-01

... substituting equivalent or superior control technology, provided such technology meets applicable emission... operator shall meet the following deadlines for design and construction of the emission control equipment... binding contract to design the SO2, opacity and NOX control systems for Unit 1 and Unit 2 by March 1, 2003...

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...

40 CFR 86.094-3 - Abbreviations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Petroleum Gas NMHC—Nonmethane Hydrocarbons NMHCE—Non-Methane Hydrocarbon Equivalent PM—Particulate Matter...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission...

40 CFR 86.094-3 - Abbreviations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Petroleum Gas NMHC—Nonmethane Hydrocarbons NMHCE—Non-Methane Hydrocarbon Equivalent PM—Particulate Matter...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission...

40 CFR 86.094-3 - Abbreviations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Petroleum Gas NMHC—Nonmethane Hydrocarbons NMHCE—Non-Methane Hydrocarbon Equivalent PM—Particulate Matter...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission...

40 CFR 86.094-3 - Abbreviations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Petroleum Gas NMHC—Nonmethane Hydrocarbons NMHCE—Non-Methane Hydrocarbon Equivalent PM—Particulate Matter...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission...

40 CFR 86.094-3 - Abbreviations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Petroleum Gas NMHC—Nonmethane Hydrocarbons NMHCE—Non-Methane Hydrocarbon Equivalent PM—Particulate Matter...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission...

40 CFR 1037.615 - Hybrid vehicles and other advanced technologies.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and the equivalent non-hybrid systems as described in § 1037.550. Test the vehicles as specified in...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Special Compliance... include regenerative braking (or the equivalent) and energy storage systems, fuel cell vehicles, and...

40 CFR 94.9 - Compliance with emission standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Provisions for Emission Regulations for Compression-Ignition Marine Engines § 94.9 Compliance with emission standards. (a) The general...

40 CFR 94.9 - Compliance with emission standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Provisions for Emission Regulations for Compression-Ignition Marine Engines § 94.9 Compliance with emission standards. (a) The general...

40 CFR 94.9 - Compliance with emission standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Provisions for Emission Regulations for Compression-Ignition Marine Engines § 94.9 Compliance with emission standards. (a) The general...

40 CFR 94.9 - Compliance with emission standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Provisions for Emission Regulations for Compression-Ignition Marine Engines § 94.9 Compliance with emission standards. (a) The general...

40 CFR 94.9 - Compliance with emission standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES General Provisions for Emission Regulations for Compression-Ignition Marine Engines § 94.9 Compliance with emission standards. (a) The general...

40 CFR 86.094-25 - Maintenance.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Provisions for Emission... durability data must occur at the same mileage intervals (or equivalent intervals if engines, subsystems, or... category (i.e., emission-related or non-emission-related, critical or non-critical) of the subject...

40 CFR 92.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...

40 CFR 92.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...

40 CFR 92.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...

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 92.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...

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 92.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Auxiliary emission control device (AECD) means any element of design which senses temperature, locomotive... those devices, systems or elements of design which control or reduce the emission of substances from an... Equivalent means the sum of the carbon mass contributions of non-oxygenated hydrocarbons, alcohols and...

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...

40 CFR 1036.230 - Selecting engine families.

Code of Federal Regulations, 2014 CFR

2014-07-01

... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES Certifying Engine Families... sold into non-vocational tractor applications. You may assign the numbers and configurations of engines...). (d) Engine configurations within an engine family must use equivalent greenhouse gas emission...

40 CFR 1036.230 - Selecting engine families.

Code of Federal Regulations, 2012 CFR

2012-07-01

... CONTROLS CONTROL OF EMISSIONS FROM NEW AND IN-USE HEAVY-DUTY HIGHWAY ENGINES Certifying Engine Families... sold into non-vocational tractor applications. You may assign the numbers and configurations of engines...). (d) Engine configurations within an engine family must use equivalent greenhouse gas emission...

40 CFR Table 7 to Subpart Eeee of... - Initial Compliance With Work Practice Standards

Code of Federal Regulations, 2011 CFR

2011-07-01

... equivalent control that meets the requirements in Table 4 to this subpart, item 1.a i. After emptying and... out a leak detection and repair program or equivalent control according to one of the subparts listed... CATEGORIES National Emission Standards for Hazardous Air Pollutants: Organic Liquids Distribution (Non...

40 CFR Table 7 to Subpart Eeee of... - Initial Compliance With Work Practice Standards

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalent control that meets the requirements in Table 4 to this subpart, item 1.a i. After emptying and... out a leak detection and repair program or equivalent control according to one of the subparts listed... CATEGORIES National Emission Standards for Hazardous Air Pollutants: Organic Liquids Distribution (Non...

Final Rule for Control of Air Pollution from Aircraft and Aircraft Engines: Emission Standards and Test Procedures

EPA Pesticide Factsheets

EPA is amending the existing emission standards for oxides of nitrogen (NOx) for new commercial aircraft engines. These standards are equivalent to the NOx emission standards of the United Nations International Civil Aviation Organization (ICAO).

40 CFR 63.653 - Monitoring, recordkeeping, and implementation plan for emissions averaging.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) For each emission point included in an emissions average, the owner or operator shall perform testing, monitoring, recordkeeping, and reporting equivalent to that required for Group 1 emission points complying... internal floating roof, external roof, or a closed vent system with a control device, as appropriate to the...

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, 2014 CFR

2014-07-01

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

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...

40 CFR 1048.101 - What exhaust emission standards must my engines meet?

Code of Federal Regulations, 2013 CFR

2013-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... my engines meet? 1048.101 Section 1048.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES...

40 CFR 1048.101 - What exhaust emission standards must my engines meet?

Code of Federal Regulations, 2014 CFR

2014-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... my engines meet? 1048.101 Section 1048.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES...

40 CFR 1048.101 - What exhaust emission standards must my engines meet?

Code of Federal Regulations, 2011 CFR

2011-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... my engines meet? 1048.101 Section 1048.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES...

40 CFR 1048.101 - What exhaust emission standards must my engines meet?

Code of Federal Regulations, 2012 CFR

2012-07-01

... engineering analysis of information equivalent to such in-use data, such as data from research engines or... my engines meet? 1048.101 Section 1048.101 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES...

40 CFR 63.653 - Monitoring, recordkeeping, and implementation plan for emissions averaging.

Code of Federal Regulations, 2013 CFR

2013-07-01

... § 63.120 of subpart G; and (ii) For closed vent systems with control devices, conduct an initial design..., monitoring, recordkeeping, and reporting equivalent to that required for Group 1 emission points complying... control device. (2) The source shall implement the following procedures for each miscellaneous process...

40 CFR 1037.520 - Modeling CO2 emissions to show compliance.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Test and Modeling..., expressed in m2 and rounded to two decimal places. Where we allow you to group multiple configurations... bin based on the drag area bin of an equivalent high-roof tractor. If the high-roof tractor is in Bin...

40 CFR 1037.520 - Modeling CO2 emissions to show compliance.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Test and Modeling... to two decimal places. Where we allow you to group multiple configurations together, measure the drag... the drag area bin of an equivalent high-roof tractor. If the high-roof tractor is in Bin I or Bin II...

40 CFR 1037.520 - Modeling CO2 emissions to show compliance.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW HEAVY-DUTY MOTOR VEHICLES Test and Modeling... to two decimal places. Where we allow you to group multiple configurations together, measure the drag... the drag area bin of an equivalent high-roof tractor. If the high-roof tractor is in Bin I or Bin II...

40 CFR 63.111 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... greater than 1.0. Group 1 storage vessel means a storage vessel that meets the criteria for design storage... purposes of emissions averaging, these four technologies are considered equivalent. Reference control... equivalents. Car-seal means a seal that is placed on a device that is used to change the position of a valve...

40 CFR 63.111 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... greater than 1.0. Group 1 storage vessel means a storage vessel that meets the criteria for design storage... purposes of emissions averaging, these four technologies are considered equivalent. Reference control... equivalents. Car-seal means a seal that is placed on a device that is used to change the position of a valve...

40 CFR 63.111 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... greater than 1.0. Group 1 storage vessel means a storage vessel that meets the criteria for design storage... purposes of emissions averaging, these four technologies are considered equivalent. Reference control... equivalents. Car-seal means a seal that is placed on a device that is used to change the position of a valve...

40 CFR 63.111 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... greater than 1.0. Group 1 storage vessel means a storage vessel that meets the criteria for design storage... purposes of emissions averaging, these four technologies are considered equivalent. Reference control... equivalents. Car-seal means a seal that is placed on a device that is used to change the position of a valve...

40 CFR 63.111 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... greater than 1.0. Group 1 storage vessel means a storage vessel that meets the criteria for design storage... purposes of emissions averaging, these four technologies are considered equivalent. Reference control... equivalents. Car-seal means a seal that is placed on a device that is used to change the position of a valve...

40 CFR 90.404 - Test procedure overview.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Gaseous Exhaust... engine operating conditions to be conducted on an engine dynamometer or equivalent load and speed... also designed to determine the brake-specific emissions of non-methane hydrocarbons. The test consists...

40 CFR 90.404 - Test procedure overview.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Gaseous Exhaust Test... operating conditions to be conducted on an engine dynamometer or equivalent load and speed measurement... to determine the brake-specific emissions of non-methane hydrocarbons. The test consists of three...

40 CFR 90.404 - Test procedure overview.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Gaseous Exhaust... engine operating conditions to be conducted on an engine dynamometer or equivalent load and speed... also designed to determine the brake-specific emissions of non-methane hydrocarbons. The test consists...

40 CFR 90.404 - Test procedure overview.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Gaseous Exhaust... engine operating conditions to be conducted on an engine dynamometer or equivalent load and speed... also designed to determine the brake-specific emissions of non-methane hydrocarbons. The test consists...

40 CFR 90.404 - Test procedure overview.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Gaseous Exhaust... engine operating conditions to be conducted on an engine dynamometer or equivalent load and speed... also designed to determine the brake-specific emissions of non-methane hydrocarbons. The test consists...

40 CFR 600.002-85 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... differential (or equivalent) turns for each turn of the drive wheels. (29) “Auxiliary Emission Control Device... miles traveled by an automobile or group of automobiles per gallon of gasoline or diesel fuel consumed as computed in § 600.113 or § 600.207 or (ii) the equivalent petroleum-based fuel economy for an...

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 86.111-90 - Exhaust gas analytical system.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... of hydrocarbons, non-dispersive infrared analyzers (NDIR) for the determination of carbon monoxide... analyzers may be used if shown to yield equivalent results and if approved in advance by the Administrator...

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 86.1777-99 - Calculations; exhaust emissions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED... subpart, with the following additional requirement: (1) Organic material non-methane hydrocarbon equivalent mass for ethanol vehicles: OMNMHCEmass=NMHCmass + (13.8756/32.042) × (CH3OH)mass + (13.8756/46.064...

40 CFR 86.1777-99 - Calculations; exhaust emissions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED... subpart, with the following additional requirement: (1) Organic material non-methane hydrocarbon equivalent mass for ethanol vehicles: OMNMHCEmass=NMHCmass + (13.8756/32.042) × (CH3OH)mass + (13.8756/46.064...

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...

40 CFR 86.111-90 - Exhaust gas analytical system.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Emission... of hydrocarbons, non-dispersive infrared analyzers (NDIR) for the determination of carbon monoxide... analyzers may be used if shown to yield equivalent results and if approved in advance by the Administrator...

76 FR 65458 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-21

... control of power plant emissions, promulgation of the Transport Rule, also known as the Cross State Air Pollution Rule (CSAPR),\\2\\ was necessary to make recent reductions in power plant emissions (or equivalent... requirements of the CAA and required states to significantly reduce SO 2 and NO X emissions from power plants...

Vacuum Microelectronic Field Emission Array Devices for Microwave Amplification.

NASA Astrophysics Data System (ADS)

Mancusi, Joseph Edward

This dissertation presents the design, analysis, and measurement of vacuum microelectronic devices which use field emission to extract an electron current from arrays of silicon cones. The arrays of regularly-spaced silicon cones, the field emission cathodes or emitters, are fabricated with an integrated gate electrode which controls the electric field at the tip of the cone, and thus the electron current. An anode or collector electrode is placed above the array to collect the emission current. These arrays, which are fabricated in a standard silicon processing facility, are developed for use as high power microwave amplifiers. Field emission has been studied extensively since it was first characterized in 1928, however due to the large electric fields required practical field emission devices are difficult to make. With the development of the semiconductor industry came the development of fabrication equipment and techniques which allow for the manufacture of the precision micron-scale structures necessary for practical field emission devices. The active region of a field emission device is a vacuum, therefore the electron travel is ballistic. This analysis of field emission devices includes electric field and electron emission modeling, development of a device equivalent circuit, analysis of the parameters in the equivalent circuit, and device testing. Variations in device structure are taken into account using a statistical model based upon device measurements. Measurements of silicon field emitter arrays at DC and RF are presented and analyzed. In this dissertation, the equivalent circuit is developed from the analysis of the device structure. The circuit parameters are calculated from geometrical considerations and material properties, or are determined from device measurements. It is necessary to include the emitter resistance in the equivalent circuit model since relatively high resistivity silicon wafers are used. As is demonstrated, the circuit model accurately predicts the magnitude of the emission current at a number of typical bias current levels when the device is operating at frequencies within the range of 10 MHz to 1 GHz. At low frequencies and at high frequencies within this range, certain parameters are negligible, and simplifications may be made in the equivalent circuit model.

40 CFR 86.1818-12 - Greenhouse gas emission standards for light-duty vehicles, light-duty trucks, and medium-duty...

Code of Federal Regulations, 2014 CFR

2014-07-01

...-equivalent debits for a test group using an alternative N2O or CH4 standard; GWP = 25 if calculating CH4...) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES General Compliance Provisions for Control of Air Pollution From New and In-Use Light-Duty Vehicles, Light-Duty Trucks, and Complete Otto...

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...

78 FR 34966 - Approval and Promulgation of Air Quality Implementation Plans; Wisconsin; Removal of Gasoline...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-11

... substitute equivalent emissions reductions to compensate for any change to a SIP-approved program, as long as actual emissions in the air are not increased. ``Equivalent'' emissions reductions mean reductions which... show that compensating emissions reductions are equivalent, modeling or adequate justification must be...

40 CFR 63.5170 - How do I demonstrate compliance with the standards?

Code of Federal Regulations, 2011 CFR

2011-07-01

... for individual or groups of coil coating lines; or overall organic HAP control efficiency is at least... compliant coatings and control devices and maintaining an acceptable equivalent emission rate Average... facility. (6) Control efficiency calculation of HAP emitted. For each work station or group of work...

40 CFR 63.5170 - How do I demonstrate compliance with the standards?

Code of Federal Regulations, 2010 CFR

2010-07-01

... for individual or groups of coil coating lines; or overall organic HAP control efficiency is at least... compliant coatings and control devices and maintaining an acceptable equivalent emission rate Average... facility. (6) Control efficiency calculation of HAP emitted. For each work station or group of work...

40 CFR 86.094-2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... methane. Non-Methane 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... Loaded Vehicle Weight means the numerical average of vehicle curb weight and GVWR. Bi-directional control...

40 CFR 86.094-2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... methane. Non-Methane 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... Loaded Vehicle Weight means the numerical average of vehicle curb weight and GVWR. Bi-directional control...

40 CFR 86.094-2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... methane. Non-Methane 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... Loaded Vehicle Weight means the numerical average of vehicle curb weight and GVWR. Bi-directional control...

40 CFR 86.094-2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... methane. Non-Methane 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... Loaded Vehicle Weight means the numerical average of vehicle curb weight and GVWR. Bi-directional control...

40 CFR 86.094-2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... methane. Non-Methane 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... Loaded Vehicle Weight means the numerical average of vehicle curb weight and GVWR. Bi-directional control...

75 FR 74457 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-30

...EPA is promulgating a regulation to require monitoring and reporting of greenhouse gas emissions from petroleum and natural gas systems. This action adds this source category to the list of source categories already required to report greenhouse gas emissions. This action applies to sources with carbon dioxide equivalent emissions above certain threshold levels as described in this regulation. This action does not require control of greenhouse gases.

40 CFR 63.5170 - How do I demonstrate compliance with the standards?

Code of Federal Regulations, 2014 CFR

2014-07-01

... percent on a monthly basis for individual or groups of coil coating lines; or overall organic HAP control... combination of compliant coatings and control devices and maintaining an acceptable equivalent emission rate... facility. (6) Control efficiency calculation of HAP emitted. For each work station or group of work...

40 CFR 63.5170 - How do I demonstrate compliance with the standards?

Code of Federal Regulations, 2012 CFR

2012-07-01

... percent on a monthly basis for individual or groups of coil coating lines; or overall organic HAP control... combination of compliant coatings and control devices and maintaining an acceptable equivalent emission rate... facility. (6) Control efficiency calculation of HAP emitted. For each work station or group of work...

77 FR 66388 - Approval and Promulgation of Air Quality Implementation Plans; New Hampshire; Reasonably...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-05

... facilities in the state. Additionally, the state removed a section regarding an equivalent substitute control... a selective non-catalytic reducing (SNCR) control device to meet an emission limit of 0.975 lbs NO X... and Promulgation of Air Quality Implementation Plans; New Hampshire; Reasonably Available Control...

40 CFR 63.5170 - How do I demonstrate compliance with the standards?

Code of Federal Regulations, 2013 CFR

2013-07-01

... percent on a monthly basis for individual or groups of coil coating lines; or overall organic HAP control... combination of compliant coatings and control devices and maintaining an acceptable equivalent emission rate... facility. (6) Control efficiency calculation of HAP emitted. For each work station or group of work...

40 CFR 63.55 - Maximum achievable control technology (MACT) determinations for affected sources subject to case...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Maximum achievable control technology (MACT) determinations for affected sources subject to case-by-case determination of equivalent emission... Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air Act Sections...

40 CFR 63.55 - Maximum achievable control technology (MACT) determinations for affected sources subject to case...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 10 2012-07-01 2012-07-01 false Maximum achievable control technology (MACT) determinations for affected sources subject to case-by-case determination of equivalent emission... Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air Act Sections...

40 CFR 63.55 - Maximum achievable control technology (MACT) determinations for affected sources subject to case...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Maximum achievable control technology (MACT) determinations for affected sources subject to case-by-case determination of equivalent emission... Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air Act Sections...

40 CFR 63.55 - Maximum achievable control technology (MACT) determinations for affected sources subject to case...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Maximum achievable control technology (MACT) determinations for affected sources subject to case-by-case determination of equivalent emission... Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air Act Sections...

Thin film coatings for improved alpha/epi

NASA Technical Reports Server (NTRS)

Krisl, M. E.; Sachs, I. M.

1985-01-01

New thin film coatings were developed for fused silica, ceria doped glass, and Corning 0211 microsheet which provide increased emissivity and/or decreased solar absorption. Emissivity is enhanced by suppression of the reststrahlen reflectance and solar absorption is reduced by externally reflecting the ultraviolet portion of the solar spectrum. Optical properties of these coatings make them suitable for both solar cell cover and thermal control mirror applications. Measurements indicate equivalent environmental performance to conventional solar cell cover and thermal control mirror products.

40 CFR 1042.130 - Installation instructions for vessel manufacturers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... engine in a way that makes the engine's emission control information label hard to read during normal... equivalent format. For example, you may post instructions on a publicly available Web site for downloading or...

40 CFR 65.2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... stream components, not carbon equivalents. Car-seal means a seal that is placed on a device that is used..., flow inducing devices that transport gas or vapor from an emission point to a control device. A closed...), analyze, and provide a record of process or control system parameters. Continuous record means...

40 CFR 86.1821-01 - Evaporative/refueling family determination.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., construction and materials. (3) Fuel system. (4) Type of refueling emission control system—non-integrated or integrated with the evaporative control system. Further, if the system is non-integrated, whether or not any... equivalent component durability over the vehicle's useful life; and (3) Evidence that the groups will result...

40 CFR 86.1821-01 - Evaporative/refueling family determination.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., construction and materials. (3) Fuel system. (4) Type of refueling emission control system—non-integrated or integrated with the evaporative control system. Further, if the system is non-integrated, whether or not any... equivalent component durability over the vehicle's useful life; and (3) Evidence that the groups will result...

40 CFR 65.2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... stream components, not carbon equivalents. Car-seal means a seal that is placed on a device that is used..., flow inducing devices that transport gas or vapor from an emission point to a control device. A closed...), analyze, and provide a record of process or control system parameters. Continuous record means...

40 CFR 65.2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... stream components, not carbon equivalents. Car-seal means a seal that is placed on a device that is used..., flow inducing devices that transport gas or vapor from an emission point to a control device. A closed...), analyze, and provide a record of process or control system parameters. Continuous record means...

40 CFR 86.1821-01 - Evaporative/refueling family determination.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., construction and materials. (3) Fuel system. (4) Type of refueling emission control system—non-integrated or integrated with the evaporative control system. Further, if the system is non-integrated, whether or not any... equivalent component durability over the vehicle's useful life; and (3) Evidence that the groups will result...

40 CFR 86.1821-01 - Evaporative/refueling family determination.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., construction and materials. (3) Fuel system. (4) Type of refueling emission control system—non-integrated or integrated with the evaporative control system. Further, if the system is non-integrated, whether or not any... equivalent component durability over the vehicle's useful life; and (3) Evidence that the groups will result...

40 CFR 63.9631 - What are my monitoring requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... inspections, vibration detectors, or equivalent means. (b) Except as provided in paragraph (c) of this section... average opacity of emissions exiting each control device stack according to the requirements in § 63.9633... pollution control device other than a baghouse, wet scrubber, dry electrostatic precipitator, or wet...

40 CFR 63.9631 - What are my monitoring requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... inspections, vibration detectors, or equivalent means. (b) Except as provided in paragraph (c) of this section... average opacity of emissions exiting each control device stack according to the requirements in § 63.9633... pollution control device other than a baghouse, wet scrubber, dry electrostatic precipitator, or wet...

40 CFR 63.9631 - What are my monitoring requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... inspections, vibration detectors, or equivalent means. (b) Except as provided in paragraph (c) of this section... average opacity of emissions exiting each control device stack according to the requirements in § 63.9633... pollution control device other than a baghouse, wet scrubber, dry electrostatic precipitator, or wet...

40 CFR 1043.70 - General recordkeeping and reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... POLLUTION CONTROLS CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE... operators of non-Party vessels must keep these records as specified in the NOX Technical Code and... operator has fuel receipts (or equivalent records) for the preceding three years showing it operated using...

40 CFR 1043.70 - General recordkeeping and reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... POLLUTION CONTROLS CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE... operators of non-Party vessels must keep these records as specified in the NOX Technical Code and... operator has fuel receipts (or equivalent records) for the preceding three years showing it operated using...

40 CFR 1043.70 - General recordkeeping and reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... POLLUTION CONTROLS CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE... operators of non-Party vessels must keep these records as specified in the NOX Technical Code and... operator has fuel receipts (or equivalent records) for the preceding three years showing it operated using...

40 CFR 86.1804-01 - Acronyms and abbreviations.

Code of Federal Regulations, 2013 CFR

2013-07-01

...—Nonmethane Hydrocarbons. NMHCE—Non-Methane Hydrocarbon Equivalent. NMOG—Non-methane organic gases. NO—nitric... (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 Vehicles, Light-Duty Trucks...

40 CFR 86.1804-01 - Acronyms and abbreviations.

Code of Federal Regulations, 2010 CFR

2010-07-01

...—Nonmethane Hydrocarbons. NMHCE—Non-Methane Hydrocarbon Equivalent. NMOG—Non-methane organic gases. NO—nitric... (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 Vehicles, Light-Duty Trucks...

40 CFR 1043.70 - General recordkeeping and reporting requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... POLLUTION CONTROLS CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE... operators of non-Party vessels must keep these records as specified in the NOX Technical Code and... operator has fuel receipts (or equivalent records) for the preceding three years showing it operated using...

40 CFR 86.1804-01 - Acronyms and abbreviations.

Code of Federal Regulations, 2011 CFR

2011-07-01

...—Nonmethane Hydrocarbons. NMHCE—Non-Methane Hydrocarbon Equivalent. NMOG—Non-methane organic gases. NO—nitric... (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 Vehicles, Light-Duty Trucks...

40 CFR 1043.70 - General recordkeeping and reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... POLLUTION CONTROLS CONTROL OF NOX, SOX, AND PM EMISSIONS FROM MARINE ENGINES AND VESSELS SUBJECT TO THE... operators of non-Party vessels must keep these records as specified in the NOX Technical Code and... operator has fuel receipts (or equivalent records) for the preceding three years showing it operated using...

Assessing fugitive emissions of CH4 from high-pressure gas pipelines in the UK

NASA Astrophysics Data System (ADS)

Clancy, S.; Worrall, F.; Davies, R. J.; Almond, S.; Boothroyd, I.

2016-12-01

Concern over the greenhouse gas impact of the exploitation of unconventional natural gas from shale deposits has caused a spotlight to be shone on to the entire hydrocarbon industry. Numerous studies have developed life-cycle emissions inventories to assess the impact that hydraulic fracturing has upon greenhouse gas emissions. Incorporated within life-cycle assessments are transmission and distribution losses, including infrastructure such as pipelines and compressor stations that pressurise natural gas for transport along pipelines. Estimates of fugitive emissions from transmission, storage and distribution have been criticized for reliance on old data from inappropriate sources (1970s Russian gas pipelines). In this study, we investigate fugitive emissions of CH4 from the UK high pressure national transmission system. The study took two approaches. Firstly, CH4 concentration is detected by driving along roads bisecting high pressure gas pipelines and also along an equivalent distance along a route where no high pressure gas pipeline was nearby. Five pipelines and five equivalent control routes were driven and the test was that CH4 measurements, when adjusted for distance and wind speed, should be greater on any route with a pipe than any route without a pipe. Secondly, 5 km of a high pressure gas pipeline and 5 km of equivalent farmland, were walked and soil gas (above the pipeline where present) was analysed every 7 m using a tunable diode laser. When wind adjusted 92 km of high pressure pipeline and 72 km of control route were drive over a 10 day period. When wind and distance adjusted CH4 fluxes were significantly greater on routes with a pipeline than those without. The smallest leak detectable was 3% above ambient (1.03 relative concentration) with any leaks below 3% above ambient assumed ambient. The number of leaks detected along the pipelines correlate to the estimated length of pipe joints, inferring that there are constant fugitive CH4 emissions from these joints. When scaled up to the UK's National Transmission System pipeline length of 7600 km gives a fugitive CH4 flux of 62.6 kt CH4/yr with a CO2 equivalent of 1570 kt CO2eq/yr - this fugitive emission from high pressure pipelines is 0.14% of the annual gas supply.

A chemical reactor network for oxides of nitrogen emission prediction in gas turbine combustor

NASA Astrophysics Data System (ADS)

Hao, Nguyen Thanh

2014-06-01

This study presents the use of a new chemical reactor network (CRN) model and non-uniform injectors to predict the NOx emission pollutant in gas turbine combustor. The CRN uses information from Computational Fluid Dynamics (CFD) combustion analysis with two injectors of CH4-air mixture. The injectors of CH4-air mixture have different lean equivalence ratio, and they control fuel flow to stabilize combustion and adjust combustor's equivalence ratio. Non-uniform injector is applied to improve the burning process of the turbine combustor. The results of the new CRN for NOx prediction in the gas turbine combustor show very good agreement with the experimental data from Korea Electric Power Research Institute.

40 CFR 1045.130 - What installation instructions must I give to vessel manufacturers?

Code of Federal Regulations, 2010 CFR

2010-07-01

... engine's emission control information label hard to read during normal engine maintenance, you must place... equivalent format. For example, you may post instructions on a publicly available Web site for downloading or...

40 CFR 1054.130 - What installation instructions must I give to equipment manufacturers?

Code of Federal Regulations, 2010 CFR

2010-07-01

... makes the engine's emission control information label hard to read during normal engine maintenance, you... in an equivalent format. For example, you may post instructions on a publicly available Web site for...

Combustion characteristics and influential factors of isooctane active-thermal atmosphere combustion assisted by two-stage reaction of n-heptane

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

Lu, Xingcai; Ji, Libin; Ma, Junjun

2011-02-15

This paper presents an experimental study on the isooctane active-thermal atmosphere combustion (ATAC) which is assisted by two-stage reaction of n-heptane. The active-thermal atmosphere is created by low- and high-temperature reactions of n-heptane which is injected at intake port, and isooctane is directly injected into combustion chamber near the top dead center. The effects of isooctane injection timing, active-thermal atmosphere intensity, overall equivalence ratio, and premixed ratio on combustion characteristics and emissions are investigated. The experimental results reveal that, the isooctane ignition and combustion can be classified to thermal atmosphere combustion, active atmosphere combustion, and active-thermal atmosphere combustion respectively accordingmore » to the extent of n-heptane oxidation as well as effects of isooctane quenching and charge cooling. n-Heptane equivalence ratio, isooctane equivalence ratio and isooctane delivery advance angle are major control parameters. In one combustion cycle, the isooctane ignited and burned after those of n-heptane, and then this combustion phenomenon can also be named as dual-fuel sequential combustion (DFSC). The ignition timing of the overall combustion event is mainly determined by n-heptane equivalence ratio and can be controlled in flexibility by simultaneously adjusting isooctane equivalence ratio. The isooctane ignition regime, overall thermal efficiency, and NO{sub x} emissions show strong sensitivity to the fuel delivery advance angle between 20 CA BTDC and 25 CA BTDC. (author)« less

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.

The carbon footprint of Australian ambulance operations.

PubMed

Brown, Lawrence H; Canyon, Deon V; Buettner, Petra G; Crawford, J Mac; Judd, Jenni

2012-12-01

To determine the greenhouse gas emissions associated with the energy consumption of Australian ambulance operations, and to identify the predominant energy sources that contribute to those emissions. A two-phase study of operational and financial data from a convenience sample of Australian ambulance operations to inventory their energy consumption and greenhouse gas emissions for 1 year. State- and territory-based ambulance systems serving 58% of Australia's population and performing 59% of Australia's ambulance responses provided data for the study. Emissions for the participating systems totalled 67 390 metric tons of carbon dioxide equivalents. For ground ambulance operations, emissions averaged 22 kg of carbon dioxide equivalents per ambulance response, 30 kg of carbon dioxide equivalents per patient transport and 3 kg of carbon dioxide equivalents per capita. Vehicle fuels accounted for 58% of the emissions from ground ambulance operations, with the remainder primarily attributable to electricity consumption. Emissions from air ambulance transport were nearly 200 times those for ground ambulance transport. On a national level, emissions from Australian ambulance operations are estimated to be between 110 000 and 120 000 tons of carbon dioxide equivalents each year. Vehicle fuels are the primary source of emissions for ground ambulance operations. Emissions from air ambulance transport are substantially higher than those for ground ambulance transport. © 2012 The Authors. EMA © 2012 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

40 CFR 63.769 - Equipment leak standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... reduction in emissions of VHAP at least equivalent to that achieved by the control required in this subpart... non-facility personnel, it may be monitored after a pressure release the next time the monitoring... are exempt from the compressor control requirements of 40 CFR 61.242-3. (8) Flares used to comply with...

40 CFR 1048.130 - What installation instructions must I give to equipment manufacturers?

Code of Federal Regulations, 2010 CFR

2010-07-01

... engine in a way that makes the engine's emission control information label hard to read during normal...) Provide instructions in writing or in an equivalent format. For example, you may post instructions on a...

40 CFR 63.3370 - How do I demonstrate compliance with the emission standards?

Code of Federal Regulations, 2011 CFR

2011-07-01

... or group of web coating lines controlled by a common control device during the month. (vi) If... monthly HAP applied (Equation 6 of § 63.3370) is less than the calculated equivalent allowable organic HAP (Equation 13a or b of § 63.3370). (4) Use of a capture system and control device (i) Overall organic HAP...

Diesel bus emissions measured in a tunnel study.

PubMed

Jamriska, Milan; Morawska, Lidia; Thomas, Steven; He, Congrong

2004-12-15

The emission factors of a bus fleet consisting of approximately 300 diesel-powered buses were measured in a tunnel study under well-controlled conditions during a 2-d monitoring campaign in Brisbane. Particle number and mass concentration levels of submicrometer particles and PM2.5 were monitored by SMPS and DustTrak instruments at the tunnel's entrance and exit, respectively. Correlation between DustTrak and TEOM response to diesel emissions was assessed, and the DustTrak results were recalculated into TEOM equivalent data. The mean value of the number and mass emission factors was (3.11+/-2.41) x 10(14) particles km(-1) for submicrometer particles and 583+/-451 mg km(-1) for PM2.5 (DustTrak), respectively. TEOM PM2.5 equivalent emission factor was 267+/-207 mg km(-1). The results are in good agreement with the emission factors determined from steady-state dynamometer testing of 12 buses from the same Brisbane City bus fleet. The results indicate that when carefully designed, both approaches, the dynamometer and on-road studies, can provide comparable results, applicable for the assessment of the effect of traffic emissions on airborne particle pollution. A brief overview of emission factors determined from other on-road and dynamometer studies reported in the literature as well as with the regulatory values used for the vehicle emission inventory assessment is presented and compared with the results obtained in this study.

75 FR 22895 - Control of Emissions From New Marine Compression-Ignition Engines at or Above 30 Liters per Cylinder

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-30

...EPA is finalizing emission standards for new marine diesel engines with per-cylinder displacement at or above 30 liters (called Category 3 marine diesel engines) installed on U.S. vessels. These emission standards are equivalent to those adopted in the amendments to Annex VI to the International Convention for the Prevention of Pollution from Ships (MARPOL Annex VI). The emission standards apply in two stages--near-term standards for newly built engines will apply beginning in 2011; long-term standards requiring an 80 percent reduction in NOX emissions will begin in 2016. We are also finalizing a change to our diesel fuel program that will allow for the production and sale of 1,000 ppm sulfur fuel for use in Category 3 marine vessels. In addition, the new fuel requirements will generally forbid the production and sale of other fuels above 1,000 ppm sulfur for use in most U.S. waters, unless alternative devices, procedures, or compliance methods are used to achieve equivalent emissions reductions. We are adopting further provisions under the Act to Prevent Pollution from Ships, especially to apply the emission standards to engines covered by MARPOL Annex VI that are not covered by the Clean Air Act, and to require that these additional engines use the specified fuels (or equivalents). The final regulations also include technical amendments to our motor vehicle and nonroad engine regulations; many of these changes involve minor adjustments or corrections to our recently finalized rule for new nonroad spark-ignition engines, or adjustment to other regulatory provisions to align with this recent final rule.

PARTICULATE EMISSION CONTROL

EPA Science Inventory

Particle or particulate matter is defined as any finely divided solid or liquid material, other than uncombined water, emitted to the ambient air as measured by applicable reference methods, or an equivalent or alternative method, or by a test method specified in 40CFR50.

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...

Control of Fine Particulate (PM2.5) Emissions from Restaurant Operations.

PubMed

Whynot, Jill; Quinn, Gary; Perryman, Pamela; Votlucka, Peter

1999-09-01

This paper describes efforts to reduce particulate matter (PM) emissions from restaurant operations, including application of an existing control method to a new equipment type. Commercial charbroiling in the South Coast Air Basin results in emissions of approximately 10 tons/day of fine particulate matter ( PM 2.5) and 1.3 tons/day of volatile organic compounds (VOCs). Over a seven-year period, the South Coast Air Quality Management District worked with industry to develop test methods for measuring emissions from various cooking operations, evaluate control technologies, and develop a rule to reduce these emissions. Of the two basic types of charbroilers-chain-driven and underfired-underfired produce four times the emissions when equivalent amounts of product are cooked. Cost-effective control technology is currently available only for chain-driven charbroilers. The application of flameless catalytic oxidizers to chain-driven charbroilers was found to effectively reduce emissions by at least 83% and is cost-effective. The catalysts have been used worldwide at restaurants for several years. Research efforts are underway to identify control options for underfired charbroilers. Implementation of Rule 1138, Control of Emissions from Restaurant Operations, adopted November 14, 1997, will result in reductions of 0.5 tons/day of PM 2.5 and 0.2 tons/day of VOCs. Future rules will result in reductions from underfired charbroilers and possibly other restaurant equipment when cost-effective solutions are available.

Control of fine particulate (PM2.5) emissions from restaurant operations.

PubMed

Whynot, J; Quinn, G; Perryman, P; Votlucka, P

1999-09-01

This paper describes efforts to reduce particulate matter (PM) emissions from restaurant operations, including application of an existing control method to a new equipment type. Commercial charbroiling in the South Coast Air Basin results in emissions of approximately 10 tons/day of fine particulate matter (PM2.5) and 1.3 tons/day of volatile organic compounds (VOCs). Over a seven-year period, the South Coast Air Quality Management District worked with industry to develop test methods for measuring emissions from various cooking operations, evaluate control technologies, and develop a rule to reduce these emissions. Of the two basic types of charbroilers--chain-driven and underfired--underfired produce four times the emissions when equivalent amounts of product are cooked. Cost-effective control technology is currently available only for chain-driven charbroilers. The application of flameless catalytic oxidizers to chain-driven charbroilers was found to effectively reduce emissions by at least 83% and is cost-effective. The catalysts have been used worldwide at restaurants for several years. Research efforts are underway to identify control options for underfired charbroilers. Implementation of Rule 1138, Control of Emissions from Restaurant Operations, adopted November 14, 1997, will result in reductions of 0.5 tons/day of PM2.5 and 0.2 tons/day of VOCs. Future rules will result in reductions from underfired charbroilers and possibly other restaurant equipment when cost-effective solutions are available.

78 FR 22470 - Special Regulations; Areas of the National Park System; Yellowstone National Park; Winter Use

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-16

... for groups of non- commercially guided snowmobiles. All snowmobile operators taking part in a non... the functional equivalent of 2007 (or newer) EPA Tier 2 Model Year engine emission control technology... [email protected] (email). Please reference OMB Control Number 1024-AE15 in the subject line of your...

Effects of Passive Fuel-Air Mixing Control on Burner Emissions Via Lobed Fuel Injectors

NASA Technical Reports Server (NTRS)

Mitchell, M. G.; Smith, O. I.; Karagozian, A. R.

1999-01-01

The present experimental study examines the effects of differing levels of passive fuel-air premixing on flame structures and their associated NO(x) and CO emissions. Four alternative fuel injector geometries were explored, three of which have lobed shapes. These lobed injectors mix fuel and air and strain species inter-faces to differing extents due to streamwise vorticity generation, thus creating different local or core equivalence ratios within flow regions upstream of flame ignition and stabilization. Prior experimental studies of two of these lobed injector flowfields focused on non-reactive mixing characteristics and emissions measurements for the case where air speeds were matched above and below the fuel injector, effectively generating stronger streamwise vorticity than spanwise vorticity. The present studies examine the effects of airstream mismatch (and hence additional spanwise vorticity generation), effects of confinement of the crossflow to reduce the local equivalence ratio, and the effects of altering the geometry and position of the flameholders. NO(x) and CO emissions as well as planar laser-induced fluorescence imaging (PLIF) of seeded acetone are used to characterize injector performance and reactive flow evolution.

Passive SCR for lean gasoline NO X control: Engine-based strategies to minimize fuel penalty associated with catalytic NH 3 generation

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

Prikhodko, Vitaly Y.; Parks, James E.; Pihl, Josh A.

Lean gasoline engines offer greater fuel economy than common stoichiometric gasoline engines. However, excess oxygen prevents the use of the current three-way catalyst (TWC) to control nitrogen oxide (NO X) emissions in lean exhaust. A passive SCR concept, introduced by General Motors Global R&D, makes use of a TWC that is already onboard to generate NH 3 under slightly rich conditions, which is stored on the downstream SCR. The stored NH 3 is then used to reduce NO X emissions when the engine switches to lean operation. In this work, the effect of engine parameters, such as air-fuel equivalence ratiomore » and spark timing, on NH 3 generation over a commercial Pd-only TWC with no dedicated oxygen storage component was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine. NO X reduction, NH 3 formation, and reductant utilization processes were evaluated, and fuel efficiency was assessed and compared to the stoichiometric engine operation case. We found air-fuel equivalence ratio to be one of the most important parameters in controlling the NH 3 production; however, the rich operation necessary for NH 3 production results in a fuel consumption penalty. The fuel penalty can be minimized by adjusting spark timing to increase rich-phase engine out NO X emissions and, thereby, NH 3 levels. Additionally, higher engine out NO X during engine load increase to simulate acceleration resulted in additional fuel savings. Ultimately, a 10% fuel consumption benefit was achieved with the passive SCR approach by optimizing rich air-fuel equivalence ratio and spark timing while also utilizing acceleration load conditions.« less

Passive SCR for lean gasoline NO X control: Engine-based strategies to minimize fuel penalty associated with catalytic NH 3 generation

DOE PAGES

Prikhodko, Vitaly Y.; Parks, James E.; Pihl, Josh A.; ...

2016-02-18

Lean gasoline engines offer greater fuel economy than common stoichiometric gasoline engines. However, excess oxygen prevents the use of the current three-way catalyst (TWC) to control nitrogen oxide (NO X) emissions in lean exhaust. A passive SCR concept, introduced by General Motors Global R&D, makes use of a TWC that is already onboard to generate NH 3 under slightly rich conditions, which is stored on the downstream SCR. The stored NH 3 is then used to reduce NO X emissions when the engine switches to lean operation. In this work, the effect of engine parameters, such as air-fuel equivalence ratiomore » and spark timing, on NH 3 generation over a commercial Pd-only TWC with no dedicated oxygen storage component was evaluated on a 2.0-liter BMW lean burn gasoline direct injection engine. NO X reduction, NH 3 formation, and reductant utilization processes were evaluated, and fuel efficiency was assessed and compared to the stoichiometric engine operation case. We found air-fuel equivalence ratio to be one of the most important parameters in controlling the NH 3 production; however, the rich operation necessary for NH 3 production results in a fuel consumption penalty. The fuel penalty can be minimized by adjusting spark timing to increase rich-phase engine out NO X emissions and, thereby, NH 3 levels. Additionally, higher engine out NO X during engine load increase to simulate acceleration resulted in additional fuel savings. Ultimately, a 10% fuel consumption benefit was achieved with the passive SCR approach by optimizing rich air-fuel equivalence ratio and spark timing while also utilizing acceleration load conditions.« less

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

Bhatt, Arpit; Zhang, Yimin; Davis, Ryan

The implementation of the US Renewable Fuel Standard is expected to increase the construction and operation of new biofuel facilities. Allowing this industry to grow without adversely affecting air quality is an important sustainability goal sought by multiple stakeholders. However, little is known about how the emission controls potentially required to comply with air quality regulations might impact biorefinery cost and deployment strategies such as siting and sizing. In this study, we use a baseline design for a lignocellulosic hydrocarbon biofuel production process to assess how the integration of emission controls impacts the minimum fuel selling price (MFSP) of themore » biofuel produced. We evaluate the change in MFSP for two cases as compared to the baseline design by incorporating (i) emission controls that ensure compliance with applicable federal air regulations and (ii) advanced control options that could be used to achieve potential best available control technology (BACT) emission limits. Our results indicate that compliance with federal air regulations can be achieved with minimal impact on biofuel cost (~$0.02 per gasoline gallon equivalent (GGE) higher than the baseline price of $5.10 GGE -1). However, if air emissions must be further reduced to meet potential BACT emission limits, the cost could increase nontrivially. For example, the MFSP could increase to $5.50 GGE -1 by adopting advanced emission controls to meet potential boiler BACT limits. Finally, given tradeoffs among emission control costs, permitting requirements, and economies of scale, these results could help inform decisions about biorefinery siting and sizing and mitigate risks associated with air permitting.« less

40 CFR 63.744 - Standards: Cleaning operations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 11 2014-07-01 2014-07-01 false Standards: Cleaning operations. 63.744...

40 CFR 63.744 - Standards: Cleaning operations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Standards: Cleaning operations. 63.744...

40 CFR 63.744 - Standards: Cleaning operations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 11 2012-07-01 2012-07-01 false Standards: Cleaning operations. 63.744...

40 CFR 63.744 - Standards: Cleaning operations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Standards: Cleaning operations. 63.744...

40 CFR 63.744 - Standards: Cleaning operations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... system with equivalent emission control. (e) Exempt cleaning operations. The following cleaning...) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards: Cleaning operations. 63.744...

Emission line galaxies and active galactic nuclei in WINGS clusters

NASA Astrophysics Data System (ADS)

Marziani, P.; D'Onofrio, M.; Bettoni, D.; Poggianti, B. M.; Moretti, A.; Fasano, G.; Fritz, J.; Cava, A.; Varela, J.; Omizzolo, A.

2017-03-01

We present the analysis of the emission line galaxies members of 46 low-redshift (0.04 < z < 0.07) clusters observed by WINGS (WIde-field Nearby Galaxy cluster Survey). Emission line galaxies were identified following criteria that are meant to minimize biases against non-star-forming galaxies and classified employing diagnostic diagrams. We examined the emission line properties and frequencies of star-forming galaxies, transition objects, and active galactic nuclei (AGNs: LINERs and Seyferts), unclassified galaxies with emission lines, and quiescent galaxies with no detectable line emission. A deficit of emission line galaxies in the cluster environment is indicated by both a lower frequency, and a systematically lower Balmer emission line equivalent width and luminosity with respect to control samples; this implies a lower amount of ionized gas per unit mass and a lower star formation rate if the source is classified as Hii region. A sizable population of transition objects and of low-luminosity LINERs (≈ 10-20% of all emission line galaxies) are detected among WINGS cluster galaxies. These sources are a factor of ≈1.5 more frequent, or at least as frequent, as in control samples with respect to Hii sources. Transition objects and LINERs in clusters are most affected in terms ofline equivalent width by the environment and appear predominantly consistent with so-called retired galaxies. Shock heating can be a possible gas excitation mechanism that is able to account for observed line ratios. Specific to the cluster environment, we suggest interaction between atomic and molecular gas and the intracluster medium as a possible physical cause of line-emitting shocks. The data whose description is provided in Table B.1, and emission line catalog of the WINGS database are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/599/A83

Hydrogen enrichment for low-emission jet combustion

NASA Technical Reports Server (NTRS)

Clayton, R. M.

1978-01-01

Simultaneous gaseous pollutant emission indexes (g pollutant/kg fuel) for a research combustor with inlet air at 120,900 N/sq m (11.9 atm) pressure and 727 K (849 F) temperature are as low as 1.0 for NOx and CO and 0.5 for unburned HC. Emissions data are presented for hydrogen/jet fuel (JP-5) mixes and for jet fuel only for premixed equivalence ratios from lean blowout to 0.65. Minimized emissions were achieved at an equivalence ratio of 0.38 using 10-12 mass percent hydrogen in the total fuel to depress the lean blowout limit. They were not achievable with jet fuel alone because of the onset of lean blowout at an equivalence ratio too high to reduce the NOx emission sufficiently.

40 CFR 91.405 - Recorded information.

Code of Federal Regulations, 2014 CFR

2014-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... each mode, if applicable. (8) Exhaust sample line temperature, if applicable. (e) Test data; post-test...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Gaseous Exhaust Test Procedures § 91.405 Recorded...

40 CFR 91.405 - Recorded information.

Code of Federal Regulations, 2012 CFR

2012-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... each mode, if applicable. (8) Exhaust sample line temperature, if applicable. (e) Test data; post-test...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Gaseous Exhaust Test Procedures § 91.405 Recorded...

40 CFR 91.405 - Recorded information.

Code of Federal Regulations, 2011 CFR

2011-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... each mode, if applicable. (8) Exhaust sample line temperature, if applicable. (e) Test data; post-test...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Gaseous Exhaust Test Procedures § 91.405 Recorded...

40 CFR 91.405 - Recorded information.

Code of Federal Regulations, 2013 CFR

2013-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... each mode, if applicable. (8) Exhaust sample line temperature, if applicable. (e) Test data; post-test...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Gaseous Exhaust Test Procedures § 91.405 Recorded...

40 CFR 91.405 - Recorded information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... addition to a pre- and post-test measurement. (4) Recorder chart or equivalent. Identify for each test... each mode, if applicable. (8) Exhaust sample line temperature, if applicable. (e) Test data; post-test...) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Gaseous Exhaust Test Procedures § 91.405 Recorded...

40 CFR 65.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... approach; (2) Decreased frequency for non-continuous parameter monitoring or physical inspections; (3... stream components, not carbon equivalents. Car-seal means a seal that is placed on a device that is used..., flow inducing devices that transport gas or vapor from an emission point to a control device. A closed...

40 CFR 60.2110 - What operating limits must I meet and by when?

Code of Federal Regulations, 2014 CFR

2014-07-01

... for Commercial and Industrial Solid Waste Incineration Units Emission Limitations and Operating Limits... zero to a level equivalent to at least two times your allowable emission limit. If your PM CPMS is an... of reading PM concentration from zero to a level equivalent to two times your allowable emission...

Evidence That Isoprene Emission Is Not Limited by Cytosolic Metabolites. Exogenous Malate Does Not Invert the Reverse Sensitivity of Isoprene Emission to High [CO2].

PubMed

Rasulov, Bahtijor; Talts, Eero; Bichele, Irina; Niinemets, Ülo

2018-02-01

Isoprene is synthesized via the chloroplastic 2- C -methyl-d-erythritol 4-phosphate/1-deoxy-d-xylulose 5-phosphate pathway (MEP/DOXP), and its synthesis is directly related to photosynthesis, except under high CO 2 concentration, when the rate of photosynthesis increases but isoprene emission decreases. Suppression of MEP/DOXP pathway activity by high CO 2 has been explained either by limited supply of the cytosolic substrate precursor, phospho enol pyruvate (PEP), into chloroplast as the result of enhanced activity of cytosolic PEP carboxylase or by limited supply of energetic and reductive equivalents. We tested the PEP-limitation hypotheses by feeding leaves with the PEP carboxylase competitive inhibitors malate and diethyl oxalacetate (DOA) in the strong isoprene emitter hybrid aspen ( Populus tremula × Populus tremuloides ). Malate feeding resulted in the inhibition of net assimilation, photosynthetic electron transport, and isoprene emission rates, but DOA feeding did not affect any of these processes except at very high application concentrations. Both malate and DOA did not alter the sensitivity of isoprene emission to high CO 2 concentration. Malate inhibition of isoprene emission was associated with enhanced chloroplastic reductive status that suppressed light reactions of photosynthesis, ultimately leading to reduced isoprene substrate dimethylallyl diphosphate pool size. Additional experiments with altered oxygen concentrations in conditions of feedback-limited and non-feedback-limited photosynthesis further indicated that changes in isoprene emission rate in control and malate-inhibited leaves were associated with changes in the share of ATP and reductive equivalent supply for isoprene synthesis. The results of this study collectively indicate that malate importantly controls the chloroplast reductive status and, thereby, affects isoprene emission, but they do not support the hypothesis that cytosolic metabolite availability alters the response of isoprene emission to changes in atmospheric composition. © 2018 American Society of Plant Biologists. All Rights Reserved.

A cost effective method of meeting emission requirements from a 50 MMscfd glycol dehydrator

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

Gearhart, L.E.

1998-12-31

The removal of volatile organic compounds (VOC) and benzene, toluene, ethylbenzene, xylene (BTEX) from glycol dehydration systems does not require costly equipment or elaborate controls. This paper will describe the design and installation of a 10 equivalent try glycol dehydration unit for field gas dehydration. The absorber design minimizes the absorption of VOC and BTEX by requiring 1.0 to 1.5 gallons of glycol per pound of water removed. Glycol unit VOC emissions are effectively controlled without installing vent gas condensers which require disposal of the waste condensate. The emission control system on this unit is simple to operate, meets emissionmore » standards and the dehydrator design achieves pipeline sales gas specifications at a reasonable cost. The system reduces the VOC and BTEX by adding a stripper on the glycol going to the reboiler. A 50 MMscfd dehydrator was installed in December 1995 and the results of an emission test done in April 1997 are presented in this paper.« less

Economic implications of incorporating emission controls to mitigate air pollutants emitted from a modeled hydrocarbon-fuel biorefinery in the United States

DOE PAGES

Bhatt, Arpit; Zhang, Yimin; Davis, Ryan; ...

2016-07-15

The implementation of the US Renewable Fuel Standard is expected to increase the construction and operation of new biofuel facilities. Allowing this industry to grow without adversely affecting air quality is an important sustainability goal sought by multiple stakeholders. However, little is known about how the emission controls potentially required to comply with air quality regulations might impact biorefinery cost and deployment strategies such as siting and sizing. In this study, we use a baseline design for a lignocellulosic hydrocarbon biofuel production process to assess how the integration of emission controls impacts the minimum fuel selling price (MFSP) of themore » biofuel produced. We evaluate the change in MFSP for two cases as compared to the baseline design by incorporating (i) emission controls that ensure compliance with applicable federal air regulations and (ii) advanced control options that could be used to achieve potential best available control technology (BACT) emission limits. Our results indicate that compliance with federal air regulations can be achieved with minimal impact on biofuel cost (~$0.02 per gasoline gallon equivalent (GGE) higher than the baseline price of $5.10 GGE -1). However, if air emissions must be further reduced to meet potential BACT emission limits, the cost could increase nontrivially. For example, the MFSP could increase to $5.50 GGE -1 by adopting advanced emission controls to meet potential boiler BACT limits. Finally, given tradeoffs among emission control costs, permitting requirements, and economies of scale, these results could help inform decisions about biorefinery siting and sizing and mitigate risks associated with air permitting.« less

Pollutant emissions from flat-flame burners at high pressures

NASA Technical Reports Server (NTRS)

Maahs, H. G.; Miller, I. M.

1980-01-01

Maximum flame temperatures and pollutant emission measurements for NOx, CO, and UHC (unburned hydrocarbons) are reported for premixed methane air flat flames at constant total mass flow rate over the pressure range from 1.9 to 30 atm and for equivalence ratios from 0.84 to 1.12. For any given pressure, maxima typically occur in both the temperature and NOx emissions curves slightly to the lean side of stoichiometric conditions. The UHC emissions show minima at roughly the same equivalence ratios. The CO emissions, however, increase continually with increasing equivalence ratio. Flame temperature and NOx emissions decrease with increasing pressure, while the opposite is true for the CO and UHC emissions. The NOx data correlate reasonably well as a function of flame temperature only. Four flameholders, differing only slightly, were used. In general, the temperature and emissions data from these four flameholders are similar, but some differences also exist. These differences appear to be related to minor variations in the condition of the flameholder surfaces.

Effect of fuel-air-ratio nonuniformity on emissions of nitrogen oxides

NASA Technical Reports Server (NTRS)

Lyons, V. J.

1981-01-01

The inlet fuel-air ratio nonuniformity is studied to deterine how nitrogen oxide (NOx) emissions are affected. An increase in NOx emissions with increased fuel-air ratio nonuniformity for average equivalence ratios less than 0.7 and a decrease in NOx emissions for average equivalence ratios near stoichiometric is predicted. The degree of uniformityy of fuel-air ratio profiles that is necessary to achieve NOx emissions goals for actual engines that use lean, premixed, prevaporized combustion systems is determined.

40 CFR 70.2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... section 183(f) of the Act; (11) Any standard or other requirement of the program to control air pollution... emissions which could not reasonably pass through a stack, chimney, vent, or other functionally-equivalent... means any stationary source (or any group of stationary sources that are located on one or more...

40 CFR 63.325 - Determination of equivalent emission control technology.

Code of Federal Regulations, 2011 CFR

2011-07-01

... other than the specific system(s) examined; and (7) Information on the cross-media impacts (to water and..., and submit to the Administrator the following information to show that the alternative achieves...) and their ancillary equipment during each portion of the normal dry cleaning cycle; (2) Information...

40 CFR 63.325 - Determination of equivalent emission control technology.

Code of Federal Regulations, 2012 CFR

2012-07-01

... other than the specific system(s) examined; and (7) Information on the cross-media impacts (to water and..., and submit to the Administrator the following information to show that the alternative achieves...) and their ancillary equipment during each portion of the normal dry cleaning cycle; (2) Information...

40 CFR 63.325 - Determination of equivalent emission control technology.

Code of Federal Regulations, 2013 CFR

2013-07-01

... other than the specific system(s) examined; and (7) Information on the cross-media impacts (to water and..., and submit to the Administrator the following information to show that the alternative achieves...) and their ancillary equipment during each portion of the normal dry cleaning cycle; (2) Information...

40 CFR 63.325 - Determination of equivalent emission control technology.

Code of Federal Regulations, 2014 CFR

2014-07-01

... other than the specific system(s) examined; and (7) Information on the cross-media impacts (to water and..., and submit to the Administrator the following information to show that the alternative achieves...) and their ancillary equipment during each portion of the normal dry cleaning cycle; (2) Information...

40 CFR 90.423 - Exhaust gas analytical system; CVS grab sample.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19 KILOWATTS... detector (HFID) for the measurement of hydrocarbons, non-dispersive infrared analyzers (NDIR) for the... converted to nitric oxide before analysis. Other types of analyzers may be used if shown to yield equivalent...

40 CFR 90.423 - Exhaust gas analytical system; CVS grab sample.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19... detector (HFID) for the measurement of hydrocarbons, non-dispersive infrared analyzers (NDIR) for the... converted to nitric oxide before analysis. Other types of analyzers may be used if shown to yield equivalent...

40 CFR 90.423 - Exhaust gas analytical system; CVS grab sample.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NONROAD SPARK-IGNITION ENGINES AT OR BELOW 19... detector (HFID) for the measurement of hydrocarbons, non-dispersive infrared analyzers (NDIR) for the... converted to nitric oxide before analysis. Other types of analyzers may be used if shown to yield equivalent...

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

Fuel/air nonuniformity - Effect on nitric oxide emissions

NASA Technical Reports Server (NTRS)

Lyons, V. J.

1981-01-01

An analytical and experimental study was performed to determine the effect of inlet fuel/air profile nonuniformity on NO(x) emissions. The theoretical NO(x) levels were verified in a flame-tube rig at inlet air temperatures of 600, 700, and 800 K, 0.3 MPa rig pressure, 25 m/sec reference velocity, overall equivalence ratio of 0.6 and residence time near 0.002 sec. The theory predicts an increase in NO(x) emissions for increased fuel/air nonuniformity for average equivalence ratios less than 0.7, while for average equivalence ratios near stoichiometric, increasing the nonuniformity will decrease NO(x) emissions. The results can be used to predict the degree of uniformity of fuel/air profiles necessary to achieve NO(x) emissions goals for actual engines that use lean premixed, prevaporized combustion systems.

Methane and CO2 emissions from China's hydroelectric reservoirs: a new quantitative synthesis.

PubMed

Li, Siyue; Zhang, Quanfa; Bush, Richard T; Sullivan, Leigh A

2015-04-01

Controversy surrounds the green credentials of hydroelectricity because of the potentially large emission of greenhouse gases (GHG) from associated reservoirs. However, limited and patchy data particularly for China is constraining the current global assessment of GHG releases from hydroelectric reservoirs. This study provides the first evaluation of the CO2 and CH4 emissions from China's hydroelectric reservoirs by considering the reservoir water surface and drawdown areas, and downstream sources (including spillways and turbines, as well as river downstream). The total emission of 29.6 Tg CO2/year and 0.47 Tg CH4/year from hydroelectric reservoirs in China, expressed as CO2 equivalents (eq), corresponds to 45.6 Tg CO2eq/year, which is 2-fold higher than the current GHG emission (ca. 23 Tg CO2eq/year) from global temperate hydropower reservoirs. China's average emission of 70 g CO2eq/kWh from hydropower amounts to 7% of the emissions from coal-fired plant alternatives. China's hydroelectric reservoirs thus currently mitigate GHG emission when compared to the main alternative source of electricity with potentially far great reductions in GHG emissions and benefits possible through relatively minor changes to reservoir management and design. On average, the sum of drawdown and downstream emission including river reaches below dams and turbines, which is overlooked by most studies, represents the equivalent of 42% of the CO2 and 92% of CH4 that emit from hydroelectric reservoirs in China. Main drivers on GHG emission rates are summarized and highlight that water depth and stratification control CH4 flux, and CO2 flux shows significant negative relationships with pH, DO, and Chl-a. Based on our finding, a substantial revision of the global carbon emissions from hydroelectric reservoirs is warranted.

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.

Particulate emissions calculations from fall tillage operations using point and remote sensors.

PubMed

Moore, Kori D; Wojcik, Michael D; Martin, Randal S; Marchant, Christian C; Bingham, Gail E; Pfeiffer, Richard L; Prueger, John H; Hatfield, Jerry L

2013-07-01

Soil preparation for agricultural crops produces aerosols that may significantly contribute to seasonal atmospheric particulate matter (PM). Efforts to reduce PM emissions from tillage through a variety of conservation management practices (CMPs) have been made, but the reductions from many of these practices have not been measured in the field. A study was conducted in California's San Joaquin Valley to quantify emissions reductions from fall tillage CMP. Emissions were measured from conventional tillage methods and from a "combined operations" CMP, which combines several implements to reduce tractor passes. Measurements were made of soil moisture, bulk density, meteorological profiles, filter-based total suspended PM (TSP), concentrations of PM with an equivalent aerodynamic diameter ≤10 μm (PM) and PM with an equivalent aerodynamic diameter ≤2.5 μm (PM), and aerosol size distribution. A mass-calibrated, scanning, three-wavelength light detection and ranging (LIDAR) procedure estimated PM through a series of algorithms. Emissions were calculated via inverse modeling with mass concentration measurements and applying a mass balance to LIDAR data. Inverse modeling emission estimates were higher, often with statistically significant differences. Derived PM emissions for conventional operations generally agree with literature values. Sampling irregularities with a few filter-based samples prevented calculation of a complete set of emissions through inverse modeling; however, the LIDAR-based emissions dataset was complete. The CMP control effectiveness was calculated based on LIDAR-derived emissions to be 29 ± 2%, 60 ± 1%, and 25 ± 1% for PM, PM, and TSP size fractions, respectively. Implementation of this CMP provides an effective method for the reduction of PM emissions. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

78 FR 31315 - Kraft Pulp Mills NSPS Review

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-23

... furnaces to levels equivalent to the new source PM limits in the NESHAP for chemical recovery combustion... will enable a broader understanding of condensable PM emissions from pulp and paper combustion sources... for 0.5 seconds (no ppmdv limit). 2. Use non-combustion control device with a limit of 5 ppmdv. 3. It...

The application of a thermal efficiency maximizing control strategy for ignition timing and equivalence ratio on a natural gas-fueled Hercules G1600

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

Franklin, M.L.; Kittelson, D.B.; Leuer, R.H.

1996-10-01

A two-dimensional optimization process, which simultaneously adjusts the spark timing and equivalence ratio of a lean-burn, natural gas, Hercules G1600 engine, has been demonstrated. First, the three-dimensional surface of thermal efficiency was mapped versus spark timing and equivalence ratio at a single speed and load combination. Then the ability of the control system to find and hold the combination of timing and equivalence ratio that gives the highest thermal efficiency was explored. NO{sub x}, CO, and HC maps were also constructed from the experimental data to determine the tradeoffs between efficiency and emissions. The optimization process adds small synchronous disturbancesmore » to the spark timing and air flow while the fuel injected per cycle is held constant for four cycles. The engine speed response to these disturbances is used to determine the corrections for spark timing and equivalence ratio. The control process, in effect, uses the engine itself as the primary sensor. The control system can adapt to changes in fuel composition, operating conditions, engine wear, or other factors that may not be easily measured. Although this strategy was previously demonstrated in a Volkswagen 1.7 liter light duty engine (Frankling et al., 1994b), until now it has not been demonstrated in a heavy-duty engine. This paper covers the application of the approach to a Hercules G1600 engine.« less

Tripartite equilibrium strategy for a carbon tax setting problem in air passenger transport.

PubMed

Xu, Jiuping; Qiu, Rui; Tao, Zhimiao; Xie, Heping

2018-03-01

Carbon emissions in air passenger transport have become increasing serious with the rapidly development of aviation industry. Combined with a tripartite equilibrium strategy, this paper proposes a multi-level multi-objective model for an air passenger transport carbon tax setting problem (CTSP) among an international organization, an airline and passengers with the fuzzy uncertainty. The proposed model is simplified to an equivalent crisp model by a weighted sum procedure and a Karush-Kuhn-Tucker (KKT) transformation method. To solve the equivalent crisp model, a fuzzy logic controlled genetic algorithm with entropy-Bolitzmann selection (FLC-GA with EBS) is designed as an integrated solution method. Then, a numerical example is provided to demonstrate the practicality and efficiency of the optimization method. Results show that the cap tax mechanism is an important part of air passenger trans'port carbon emission mitigation and thus, it should be effectively applied to air passenger transport. These results also indicate that the proposed method can provide efficient ways of mitigating carbon emissions for air passenger transport, and therefore assist decision makers in formulating relevant strategies under multiple scenarios.

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

Dowdy, M.; Burke, A.; Schneider, H.

Fuel economy, exhaust emissions, multifuel capability, advanced materials and cost/manufacturability for both conventional and advanced alternative power systems were assessed. To insure valid comparisons of vehicles with alternative power systems, the concept of an Otto-Engine-Equivalent (OEE) vehicle was utilized. Each engine type was sized to provide equivalent vehicle performance. Sensitivity to different performance criteria was evaluated. Fuel economy projections are made for each engine type considering both the legislated emission standards and possible future emissions requirements.

C III] Emission in Star-forming Galaxies Near and Far

NASA Astrophysics Data System (ADS)

Rigby, J. R.; Bayliss, M. B.; Gladders, M. D.; Sharon, K.; Wuyts, E.; Dahle, H.; Johnson, T.; Peña-Guerrero, M.

2015-11-01

We measure [C iii] 1907, C iii] 1909 Å emission lines in 11 gravitationally lensed star-forming galaxies at z ˜ 1.6-3, finding much lower equivalent widths than previously reported for fainter lensed galaxies. While it is not yet clear what causes some galaxies to be strong C iii] emitters, C iii] emission is not a universal property of distant star-forming galaxies. We also examine C iii] emission in 46 star-forming galaxies in the local universe, using archival spectra from GHRS, FOS, and STIS on HST and IUE. Twenty percent of these local galaxies show strong C iii] emission, with equivalent widths < -5 Å. Three nearby galaxies show C iii] emission equivalent widths as large as the most extreme emitters yet observed in the distant universe; all three are Wolf-Rayet galaxies. At all redshifts, strong C iii] emission may pick out low-metallicity galaxies experiencing intense bursts of star formation. Such local C iii] emitters may shed light on the conditions of star formation in certain extreme high-redshift galaxies.

C III] Emission in Star-Forming Galaxies Near and Far

NASA Technical Reports Server (NTRS)

Rigby, J, R.; Bayliss, M. B.; Gladders, M. D.; Sharon, K.; Wuyts, E.; Dahle, H.; Johnson, T.; Pena-Guerrero, M.

2015-01-01

We measure C III Lambda Lambda 1907, 1909 Angstrom emission lines in eleven gravitationally-lensed star-forming galaxies at zeta at approximately 1.6-3, finding much lower equivalent widths than previously reported for fainter lensed galaxies (Stark et al. 2014). While it is not yet clear what causes some galaxies to be strong C III] emitters, C III] emission is not a universal property of distant star-forming galaxies. We also examine C III] emission in 46 star-forming galaxies in the local universe, using archival spectra from GHRS, FOS, and STIS on HST, and IUE. Twenty percent of these local galaxies show strong C III] emission, with equivalent widths less than -5 Angstrom. Three nearby galaxies show C III] emission equivalent widths as large as the most extreme emitters yet observed in the distant universe; all three are Wolf-Rayet galaxies. At all redshifts, strong C III] emission may pick out low-metallicity galaxies experiencing intense bursts of star formation. Such local C III] emitters may shed light on the conditions of star formation in certain extreme high-redshift galaxies.

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.

Performance and Exhaust Emissions in a Natural-Gas Fueled Dual-Fuel Engine

NASA Astrophysics Data System (ADS)

Shioji, Masahiro; Ishiyama, Takuji; Ikegami, Makoto; Mitani, Shinichi; Shibata, Hiroaki

In order to establish the optimum fueling in a natural gas fueled dual fuel engine, experiments were done for some operational parameters on the engine performances and the exhaust emissions. The results show that the pilot fuel quantity should be increased and its injection timing should be advanced to suppress unburned hydrocarbon emission in the middle and low output range, while the quantity should be reduced and the timing retarded to avoid onset of knock at high loads. Unburned hydrocarbon emission and thermal efficiency are improved by avoiding too lean natural gas mixture by restricting intake charge air. However, the improvement is limited because the ignition of pilot fuel deteriorates with excessive throttling. It is concluded that an adequate combination of throttle control and equivalence ratio ensures low hydrocarbon emission and the thermal efficiency comparable to diesel operation.

40 CFR Table 18 to Subpart Uuu of... - Requirements for Performance Tests for Organic HAP Emissions From Catalytic Reforming Units

Code of Federal Regulations, 2010 CFR

2010-07-01

... part 60, appendix A), as applicable c. Measure TOC concentration (for percent reduction standard) Method 25 (40 part 60, appendix A) to measure nonmethane TOC concentration (in carbon equivalents) at inlet and outlet of the control device. If the nonmethane TOC outlet concentration is expected to be...

40 CFR 75.53 - Monitoring plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Energy and used in the National Allowance Data Base (or equivalent facility ID number assigned by EPA, if...; (C) Type of boiler (or boilers for a group of units using a common stack); (D) Type of fuel(s) fired... more than one fuel, the fuel classification of the boiler; (E) Type(s) of emission controls for SO2...

40 CFR 75.53 - Monitoring plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Energy and used in the National Allowance Data Base (or equivalent facility ID number assigned by EPA, if...; (C) Type of boiler (or boilers for a group of units using a common stack); (D) Type of fuel(s) fired... more than one fuel, the fuel classification of the boiler; (E) Type(s) of emission controls for SO2...

40 CFR 63.6125 - What are my monitor installation, operation, and maintenance requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... emission control device, you must monitor on a continuous basis your catalyst inlet temperature in order to... combustion turbine which fires landfill gas or digester gas equivalent to 10 percent or more of the gross... the major source with a non-resettable hour meter to measure the number of hours that distillate oil...

40 CFR 63.6125 - What are my monitor installation, operation, and maintenance requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... emission control device, you must monitor on a continuous basis your catalyst inlet temperature in order to... combustion turbine which fires landfill gas or digester gas equivalent to 10 percent or more of the gross... the major source with a non-resettable hour meter to measure the number of hours that distillate oil...

Lean, premixed, prevaporized fuel combustor conceptual design study

NASA Technical Reports Server (NTRS)

Fiorentino, A. J.; Greene, W.; Kim, J.

1979-01-01

Four combustor concepts, designed for the energy efficient engine, utilize variable geometry or other flow modulation techniques to control the equivalence ratio of the initial burning zone. Lean conditions are maintained at high power to control oxides of nitrogen while near stoichometric conditions are maintained at low power for low CO and THC emissions. Each concept was analyzed and ranked for its potential in meeting the goals of the program. Although the primary goal of the program is a low level of nitric oxide emissions at stratospheric cruise conditions, both the ground level EPA emission standards and combustor performance and operational requirements typical of advanced subsonic aircraft engines are retained as goals as well. Based on the analytical projections made, two of the concepts offer the potential of achieving the emission goals; however, the projected operational characteristics and reliability of any concept to perform satisfactorily over an entire aircraft flight envelope would require extensive experimental substantiation before engine adaptation can be considered.

Historical evaluation of vehicle emission control in Guangzhou based on a multi-year emission inventory

NASA Astrophysics Data System (ADS)

Zhang, Shaojun; Wu, Ye; Liu, Huan; Wu, Xiaomeng; Zhou, Yu; Yao, Zhiliang; Fu, Lixin; He, Kebin; Hao, Jiming

2013-09-01

The Guangzhou government adopted many vehicle emission control policies and strategies during the five-year preparation (2005-2009) to host the 2010 Asian Games. This study established a multi-year emission inventory for vehicles in Guangzhou during 2005-2009 and estimated the uncertainty in total vehicle emissions by taking the assumed uncertainties in fleet-average emission factors and annual mileage into account. In 2009, the estimated total vehicle emissions in Guangzhou were 313 000 (242 000-387 000) tons of CO, 60 900 (54 000-70 200) tons of THC, 65 600 (56 800-74 100) tons of NOx and 2740 (2100-3400) tons of PM10. Vehicle emissions within the urban area of Guangzhou were estimated to be responsible for ˜40% of total gaseous pollutants and ˜25% of total PM10 in the entire city. Although vehicle use intensity increased rapidly in Guangzhou during 2005-2009, vehicle emissions were estimated to have been reduced by 12% for CO, 21% for THC and 20% for PM10 relative to those in 2005. NOx emissions were estimated to have remained almost constant during this period. Compared to the "without control" scenario, 19% (15%-23%) of CO, 20% (18%-23%) of THC, 9% (8%-10%) of NOx and 16% (12%-20%) of PM10 were estimated to have been mitigated from a combination of the implementation of Euro III standards for light-duty vehicles (LDVs) and heavy-duty diesel vehicles and improvement of fuel quality. This study also evaluated several enhanced vehicle emission control actions taken recently. For example, the enhanced I/M program for LDVs was estimated to reduce 11% (9%-14%) of CO, 9% (8%-10%) of THC and 2% (2%-3%) of NOx relative to total vehicle emissions in 2009. Total emission reductions by temporary traffic controls for the Asian Games were estimated equivalent to 9% (7%-11%) of CO, 9% (8%-10%) of THC, 5% (5%-6%) of NOx and 10% (8%-13%) of PM10 estimated total vehicle emissions in 2009. Those controls are essential to further vehicle emission mitigation in Guangzhou required by the new National Ambient Air Quality Standards.

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.

40 CFR 88.105-94 - Clean-fuel fleet emission standards for heavy-duty engines.

Code of Federal Regulations, 2010 CFR

2010-07-01

... exceed 3.8 grams per brake horsepower-hour. (2) Combined emissions of oxides of nitrogen and nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 3.5 grams per brake horsepower-hour when... nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 2.5 grams per brake...

40 CFR 88.105-94 - Clean-fuel fleet emission standards for heavy-duty engines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... exceed 3.8 grams per brake horsepower-hour. (2) Combined emissions of oxides of nitrogen and nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 3.5 grams per brake horsepower-hour when... nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 2.5 grams per brake...

40 CFR 88.105-94 - Clean-fuel fleet emission standards for heavy-duty engines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... exceed 3.8 grams per brake horsepower-hour. (2) Combined emissions of oxides of nitrogen and nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 3.5 grams per brake horsepower-hour when... nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 2.5 grams per brake...

40 CFR 88.105-94 - Clean-fuel fleet emission standards for heavy-duty engines.

Code of Federal Regulations, 2014 CFR

2014-07-01

... exceed 3.8 grams per brake horsepower-hour. (2) Combined emissions of oxides of nitrogen and nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 3.5 grams per brake horsepower-hour when... nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 2.5 grams per brake...

40 CFR 88.105-94 - Clean-fuel fleet emission standards for heavy-duty engines.

Code of Federal Regulations, 2012 CFR

2012-07-01

... exceed 3.8 grams per brake horsepower-hour. (2) Combined emissions of oxides of nitrogen and nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 3.5 grams per brake horsepower-hour when... nonmethane hydrocarbons (or nonmethane hydrocarbon equivalent) shall not exceed 2.5 grams per brake...

A rational procedure for estimation of greenhouse-gas emissions from municipal wastewater treatment plants.

PubMed

Monteith, Hugh D; Sahely, Halla R; MacLean, Heather L; Bagley, David M

2005-01-01

Municipal wastewater treatment may lead to the emission of greenhouse gases. The current Intergovenmental Panel on Climate Change (Geneva, Switzerland) approach attributes only methane emissions to wastewater treatment, but this approach may overestimate greenhouse gas emissions from the highly aerobic processes primarily used in North America. To better estimate greenhouse gas emissions, a procedure is developed that can be used either with plant-specific data or more general regional data. The procedure was evaluated using full-scale data from 16 Canadian wastewater treatment facilities and then applied to all 10 Canadian provinces. The principal greenhouse gas emitted from municipal wastewater treatment plants was estimated to be carbon dioxide (CO2), with very little methane expected. The emission rates ranged from 0.005 kg CO2-equivalent/m3 treated for primary treatment facilities to 0.26 kg CO2-equivalent/m3 for conventional activated sludge, with anaerobic sludge digestion to over 0.8 kg CO2-equivalent/m3 for extended aeration with aerobic digestion. Increasing the effectiveness of biogas generation and use will decrease the greenhouse gas emissions that may be assigned to the wastewater treatment plant.

Measurements of atmospheric hydrocarbons and biogenic emission fluxes in the Amazon boundary layer

NASA Technical Reports Server (NTRS)

Zimmerman, P. R.; Greenberg, J. P.; Westberg, C. E.

1988-01-01

Tropospheric mixing ratios of methane, C2-C10 hydrocarbons, and carbon monoxide were measured over the Amazon tropical forest near Manaus, Amazonas, Brazil, in July and August 1985. The measurements, consisting mostly of altitude profiles of these gases, were all made within the atmospheric boundary layer up to an altitude of 1000 m above ground level. Data characterize the diurnal hydrocarbon composition of the boundary layer. Biogenic emissions of isoprene control hydroxyl radical concentrations over the forest. Biogenic emission fluxes of isoprene and terpenes are estimated to be 25,000 micrograms/sq m per day and 5600 micrograms/sq m per day, respectively. This isoprene emission is equivalent to 2 percent of the net primary productivity of the tropical forest. Atmospheric oxidation of biogenic isoprene and terpenes emissions from the Amazon forest may account for daily increases of 8-13 ppb for carbon monoxide in the planetary boundary layer.

Framing Climate Goals in Terms of Cumulative CO2-Forcing-Equivalent Emissions

NASA Astrophysics Data System (ADS)

Jenkins, S.; Millar, R. J.; Leach, N.; Allen, M. R.

2018-03-01

The relationship between cumulative CO2 emissions and CO2-induced warming is determined by the Transient Climate Response to Emissions (TCRE), but total anthropogenic warming also depends on non-CO2 forcing, complicating the interpretation of emissions budgets based on CO2 alone. An alternative is to frame emissions budgets in terms of CO2-forcing-equivalent (CO2-fe) emissions—the CO2 emissions that would yield a given total anthropogenic radiative forcing pathway. Unlike conventional "CO2-equivalent" emissions, these are directly related to warming by the TCRE and need to fall to zero to stabilize warming: hence, CO2-fe emissions generalize the concept of a cumulative carbon budget to multigas scenarios. Cumulative CO2-fe emissions from 1870 to 2015 inclusive are found to be 2,900 ± 600 GtCO2-fe, increasing at a rate of 67 ± 9.5 GtCO2-fe/yr. A TCRE range of 0.8-2.5°C per 1,000 GtC implies a total budget for 0.6°C of additional warming above the present decade of 880-2,750 GtCO2-fe, with 1,290 GtCO2-fe implied by the Coupled Model Intercomparison Project Phase 5 median response, corresponding to 19 years' CO2-fe emissions at the current rate.

Critical research and advanced technology (CRT) support project

NASA Technical Reports Server (NTRS)

Furman, E. R.; Anderson, D. N.; Hodge, P. E.; Lowell, C. E.; Nainiger, J. J.; Schultz, D. F.

1983-01-01

A critical technology base for utility and industrial gas turbines by planning the use of coal-derived fuels was studied. Development tasks were included in the following areas: (1) Combustion - investigate the combustion of coal-derived fuels and methods to minimize the conversion of fuel-bound nitrogen to NOx; (2) materials - understand and minimize hot corrosion; (3) system studies - integrate and focus the technological efforts. A literature survey of coal-derived fuels was completed and a NOx emissions model was developed. Flametube tests of a two-stage (rich-lean) combustor defined optimum equivalence ratios for minimizing NOx emissions. Sector combustor tests demonstrated variable air control to optimize equivalence ratios over a wide load range and steam cooling of the primary zone liner. The catalytic combustion of coal-derived fuels was demonstrated. The combustion of coal-derived gases is very promising. A hot-corrosion life prediction model was formulated and verified with laboratory testing of doped fuels. Fuel additives to control sulfur corrosion were studied. The intermittent application of barium proved effective. Advanced thermal barrier coatings were developed and tested. Coating failure modes were identified and new material formulations and fabrication parameters were specified. System studies in support of the thermal barrier coating development were accomplished.

Automotive technology status and projections. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Dowdy, M.; Burke, A.; Schneider, H.; Edmiston, W.; Klose, G. J.; Heft, R.

1978-01-01

Fuel economy, exhaust emissions, multifuel capability, advanced materials and cost/manufacturability for both conventional and advanced alternative power systems were assessed. To insure valid comparisons of vehicles with alternative power systems, the concept of an Otto-Engine-Equivalent (OEE) vehicle was utilized. Each engine type was sized to provide equivalent vehicle performance. Sensitivity to different performance criteria was evaluated. Fuel economy projections are made for each engine type considering both the legislated emission standards and possible future emissions requirements.

Effect of primary-zone equivalence ratio and hydrogen addition on exhaust emission in a hydrocarbon-fueled combustor

NASA Technical Reports Server (NTRS)

Norgren, C. T.; Ingebo, R. D.

1974-01-01

The effects of reducing the primary-zone equivalence ratio on the exhaust emission levels of oxides of nitrogen, carbon monoxide, and unburned hydrocarbons in experimental hydrocarbon-fueled combustor segments at simulated supersonic cruise and idle conditions were investigated. In addition, the effects of the injection of hydrogen fuel (up to 4 percent of the total weight of fuel) on the stability of the hydrocarbon flame and exhaust emissions were studied and compared with results obtained without hydrogen addition.

Experiential study on temperature and emission performance of micro burner during porous media combustion

NASA Astrophysics Data System (ADS)

Janvekar, Ayub Ahmed; Abdullah, M. Z.; Ahmad, Z. A.; Abas, A.; Ismail, A. K.; Hussien, A. A.; Kataraki, P. S.; Ishak, M. H. H.; Mazlan, M.; Zubair, A. F.

2018-05-01

Addition of porous materials in reaction zone give rise to significant improvements in combustion performance. In this work, a dual layered micro porous media burner was tested for stable flame and emissions. Reaction and preheat layer was made up of discrete (zirconia) and foam (porcelain) type of materials respectively. Three different thickness of reaction zone was tested, each with 10, 20 and 30mm. Interestingly, only 20mm thick layer can able to show better thermal efficiency of 72% as compared to 10 and 30mm. Best equivalence ratio came out to be 0.7 for surface and 0.6 for submerged flame conditions. Moreover, emission was continuously monitored to detect presence of NOx and CO, which were under controlled limits.

Environmental and economic evaluation of bioenergy in Ontario, Canada

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

Yimin Zhang; Shiva Habibi; Heather L. MacLean

2007-08-15

We examined life cycle environmental and economic implications of two near-term scenarios for converting cellulosic biomass to energy, generating electricity from cofiring biomass in existing coal power plants, and producing ethanol from biomass in stand-alone facilities in Ontario, Canada. The study inventories near-term biomass supply in the province, quantifies environmental metrics associated with the use of agricultural residues for producing electricity and ethanol, determines the incremental costs of switching from fossil fuels to biomass, and compares the cost-effectiveness of greenhouse gas (GHG) and air pollutant emissions abatement achieved through the use of the bioenergy. Implementing a biomass cofiring rate of 10% in existing coal-fired power plants would reduce annual GHG emissions by 2.3 million metric tons (t) of CO{sub 2} equivalent (7% of the province's coal power plant emissions). The substitution of gasoline with ethanol/gasoline blends would reduce annual provincial light-duty vehicle fleet emissions between 1.3 and 2.5 million t of CO{sub 2} equivalent (3.5-7% of fleet emissions). If biomass sources other than agricultural residues were used, additional emissions reductions could be realized. At current crude oil prices (more » $70/barrel) and levels of technology development of the bioenergy alternatives, the biomass electricity cofiring scenario analyzed is more cost-effective for mitigating GHG emissions ($$22/t of CO{sub 2} equivalent for a 10% cofiring rate) than the stand-alone ethanol production scenario ($$92/t of CO{sub 2} equivalent). 67 refs., 5 figs., 7 tabs.« less

An Atlas of Computed Equivalent Widths of Quasar Broad Emission Lines

NASA Astrophysics Data System (ADS)

Korista, Kirk; Baldwin, Jack; Ferland, Gary; Verner, Dima

We present graphically the results of several thousand photoionization calculations of broad emission-line clouds in quasars, spanning 7 orders of magnitude in hydrogen ionizing flux and particle density. The equivalent widths of 42 quasar emission lines are presented as contours in the particle density-ionizing flux plane for a typical incident continuum shape, solar chemical abundances, and cloud column density of N(H) = 1023 cm-2. Results are similarly given for a small subset of emission lines for two other column densities (1022 and 1024 cm-2), five other incident continuum shapes, and a gas metallicity of 5 Z⊙. These graphs should prove useful in the analysis of quasar emission-line data and in the detailed modeling of quasar broad emission-line regions. The digital results of these emission-line grids and many more are available over the Internet.

Method and apparatus for controlling fuel/air mixture in a lean burn engine

DOEpatents

Kubesh, John Thomas; Dodge, Lee Gene; Podnar, Daniel James

1998-04-07

The system for controlling the fuel/air mixture supplied to a lean burn engine when operating on natural gas, gasoline, hydrogen, alcohol, propane, butane, diesel or any other fuel as desired. As specific humidity of air supplied to the lean burn engine increases, the oxygen concentration of exhaust gas discharged by the engine for a given equivalence ratio will decrease. Closed loop fuel control systems typically attempt to maintain a constant exhaust gas oxygen concentration. Therefore, the decrease in the exhaust gas oxygen concentration resulting from increased specific humidity will often be improperly attributed to an excessive supply of fuel and the control system will incorrectly reduce the amount of fuel supplied to the engine. Also, the minimum fuel/air equivalence ratio for a lean burn engine to avoid misfiring will increase as specific humidity increases. A relative humidity sensor to allow the control system to provide a more enriched fuel/air mixture at high specific humidity levels. The level of specific humidity may be used to compensate an output signal from a universal exhaust gas oxygen sensor for changing oxygen concentrations at a desired equivalence ratio due to variation in specific humidity specific humidity. As a result, the control system will maintain the desired efficiency, low exhaust emissions and power level for the associated lean burn engine regardless of the specific humidity level of intake air supplied to the lean burn engine.

40 CFR 61.273 - Alternative means of emission limitation.

Code of Federal Regulations, 2012 CFR

2012-07-01

... for Benzene Emissions From Benzene Storage Vessels § 61.273 Alternative means of emission limitation... benzene emissions at least equivalent to the reduction in emissions achieved by any requirement in § 61... full-size or scale-model storage vessels that accurately collect and measure all benzene emissions from...

40 CFR 61.273 - Alternative means of emission limitation.

Code of Federal Regulations, 2014 CFR

2014-07-01

... for Benzene Emissions From Benzene Storage Vessels § 61.273 Alternative means of emission limitation... benzene emissions at least equivalent to the reduction in emissions achieved by any requirement in § 61... full-size or scale-model storage vessels that accurately collect and measure all benzene emissions from...

40 CFR 61.273 - Alternative means of emission limitation.

Code of Federal Regulations, 2013 CFR

2013-07-01

... for Benzene Emissions From Benzene Storage Vessels § 61.273 Alternative means of emission limitation... benzene emissions at least equivalent to the reduction in emissions achieved by any requirement in § 61... full-size or scale-model storage vessels that accurately collect and measure all benzene emissions from...

40 CFR 61.273 - Alternative means of emission limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... for Benzene Emissions From Benzene Storage Vessels § 61.273 Alternative means of emission limitation... benzene emissions at least equivalent to the reduction in emissions achieved by any requirement in § 61... full-size or scale-model storage vessels that accurately collect and measure all benzene emissions from...

40 CFR 61.273 - Alternative means of emission limitation.

Code of Federal Regulations, 2011 CFR

2011-07-01

... for Benzene Emissions From Benzene Storage Vessels § 61.273 Alternative means of emission limitation... benzene emissions at least equivalent to the reduction in emissions achieved by any requirement in § 61... full-size or scale-model storage vessels that accurately collect and measure all benzene emissions from...

Comparative Study of Hybrid Powertrains on Fuel Saving, Emissions, and Component Energy Loss in HD Trucks

DOE PAGES

Gao, Zhiming; Finney, Charles; Daw, Charles; ...

2014-09-30

We compared parallel and series hybrid powertrains on fuel economy, component energy loss, and emissions control in Class 8 trucks over both city and highway driving. A comprehensive set of component models describing battery energy, engine fuel efficiency, emissions control, and power demand interactions for heavy duty (HD) hybrids has been integrated with parallel and series hybrid Class 8 trucks in order to identify the technical barriers of these hybrid powertrain technologies. The results show that series hybrid is absolutely negative for fuel economy benefit of long-haul trucks due to an efficiency penalty associated with the dual-step conversions of energymore » (i.e. mechanical to electric to mechanical). The current parallel hybrid technology combined with 50% auxiliary load reduction could elevate 5-7% fuel economy of long-haul trucks, but a profound improvement of long-haul truck fuel economy requires additional innovative technologies for reducing aerodynamic drag and rolling resistance losses. The simulated emissions control indicates that hybrid trucks reduce more CO and HC emissions than conventional trucks. The simulated results further indicate that the catalyzed DPF played an important role in CO oxidations. Limited NH 3 emissions could be slipped from the Urea SCR, but the average NH 3 emissions are below 20 ppm. Meanwhile our estimations show 1.5-1.9% of equivalent fuel-cost penalty due to urea consumption in the simulated SCR cases.« less

75 FR 53883 - Action To Ensure Authority To Issue Permits Under the Prevention of Significant Deterioration...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-02

... long-lived and directly emitted GHGs--carbon dioxide (CO 2 ), methane (CH 4 ), nitrous oxide (N 2 O... carbon dioxide equivalent (CO 2 e) but only if the project also significantly increase emissions of at... emissions must be calculated on both a mass basis and, as alluded to above, a carbon dioxide equivalent (CO...

Investigation of a tripropylene-glycol monomethyl ether and diesel blend for soot-free combustion in an optical direct-injection diesel engine

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

Dumitrescu, Cosmin E.; Mueller, Charles J.; Kurtz, Eric

Natural luminosity and chemiluminescence imaging diagnostics were employed to investigate if a 50/50 blend by volume of tripropylene-glycol monomethyl ether (TPGME) and ultra-low sulfur #2 diesel certification fuel (CF) could enable leaner-lifted flame combustion (LLFC), a non-sooting mode of mixing-controlled combustion associated with equivalence ratios below approximately 2. The experiments were performed in a singlecylinder heavy-duty optical compression-ignition engine at three injection pressures and three dilution levels. Results indicate that TPGME addition effectively eliminated engine-out smoke emissions by curtailing soot production and/or increasing soot oxidation during and after the end of fuel injection. TPGME greatly reduced soot luminosity when compared with neat CF, but did not enable LLFC because the equivalence ratios at the lift-off length,more » $$\\phi$$(H), never reached the non-sooting limit. Nevertheless, this study showed that TPGME addition has the potential to enable LLFC under different experimental conditions that would further decrease $$\\phi$$(H) to ~ 2 and below. Concerning other engine-out emissions, injection pressure influenced the effects of TPGME addition on NO x emissions. Finally, HC and CO emissions were higher compared to baseline fuel likely due to the lower net heat of combustion of TPGME and the need to limit fuel-injection duration for valid optical measurements.« less

Investigation of a tripropylene-glycol monomethyl ether and diesel blend for soot-free combustion in an optical direct-injection diesel engine

DOE PAGES

Dumitrescu, Cosmin E.; Mueller, Charles J.; Kurtz, Eric

2015-12-31

Natural luminosity and chemiluminescence imaging diagnostics were employed to investigate if a 50/50 blend by volume of tripropylene-glycol monomethyl ether (TPGME) and ultra-low sulfur #2 diesel certification fuel (CF) could enable leaner-lifted flame combustion (LLFC), a non-sooting mode of mixing-controlled combustion associated with equivalence ratios below approximately 2. The experiments were performed in a singlecylinder heavy-duty optical compression-ignition engine at three injection pressures and three dilution levels. Results indicate that TPGME addition effectively eliminated engine-out smoke emissions by curtailing soot production and/or increasing soot oxidation during and after the end of fuel injection. TPGME greatly reduced soot luminosity when compared with neat CF, but did not enable LLFC because the equivalence ratios at the lift-off length,more » $$\\phi$$(H), never reached the non-sooting limit. Nevertheless, this study showed that TPGME addition has the potential to enable LLFC under different experimental conditions that would further decrease $$\\phi$$(H) to ~ 2 and below. Concerning other engine-out emissions, injection pressure influenced the effects of TPGME addition on NO x emissions. Finally, HC and CO emissions were higher compared to baseline fuel likely due to the lower net heat of combustion of TPGME and the need to limit fuel-injection duration for valid optical measurements.« less

Numerical investigation of exhaust gas emissions for a dual fuel engine configuration using diesel and pongamia oil.

PubMed

Mohamed Ibrahim, N H; Udayakumar, M

2016-12-01

The investigation presented in this paper focuses on determination of gaseous exhaust emissions by computational simulation during combustion in compression ignition engine with pongamia oil substitution. Combustion is modeled using Equilibrium Constants Method (ECM) with MATLAB program to calculate the mole fraction of 10 combustion products when pongamia oil is burnt along with diesel at variable equivalence ratio and blend ratio. It had been observed that pongamia oil substitution causes decrease in the CO emission and increase in the NO x emission as the blend ratio as well as equivalence ratio increases. Copyright © 2015 Elsevier Inc. All rights reserved.

Ammonia emission factors from broiler litter in barns, in storage, and after land application.

PubMed

Moore, Philip A; Miles, Dana; Burns, Robert; Pote, Dan; Berg, Kess; Choi, In Hag

2011-01-01

We measured NH₃ emissions from litter in broiler houses, during storage, and after land application and conducted a mass balance of N in poultry houses. Four state-of-the-art tunnel-ventilated broiler houses in northwest Arkansas were equipped with NH₃ sensors, anemometers, and data loggers to continuously record NH₃ concentrations and ventilation for 1 yr. Gaseous fluxes of NH₃, N₂O, CH₄, and CO₂ from litter were measured. Nitrogen (N) inputs and outputs were quantified. Ammonia emissions during storage and after land application were measured. Ammonia emissions during the flock averaged approximately 15.2 kg per day-house (equivalent to 28.3 g NH₃per bird marketed). Emissions between flocks equaled 9.09 g NH₃ per bird. Hence, in-house NH₃ emissions were 37.5 g NH₃ per bird, or 14.5 g kg(-1) bird marketed (50-d-old birds). The mass balance study showed N inputs for the year to the four houses totaled 71,340 kg N, with inputs from bedding, chicks, and feed equal to 303, 602, and 70,435 kg, respectively (equivalent to 0.60, 1.19, and 139.56 g N per bird). Nitrogen outputs totaled 70,396 kg N. Annual N output from birds marketed, NH₃ emissions, litter or cake, mortality, and NO₂ emissions was 39,485, 15,571, 14,464, 635, and 241 kg N, respectively (equivalent to 78.2, 30.8, 28.7, 1.3, and 0.5 g N per bird). The percent N recovery for the N mass balance study was 98.8%. Ammonia emissions from stacked litter during a 16-d storage period were 172 g Mg(-1) litter, which is equivalent to 0.18 g NH₃ per bird. Ammonia losses from poultry litter broadcast to pastures were 34 kg N ha (equivalent to 15% of total N applied or 7.91 g NH₃ per bird). When the litter was incorporated into the pasture using a new knifing technique, NH₃ losses were virtually zero. The total NH₃ emission factor for broilers measured in this study, which includes losses in-house, during storage, and after land application, was 45.6 g NH₃ per bird marketed. by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Current and Projected Carbon Dynamics in US Agricultural Systems

NASA Astrophysics Data System (ADS)

Ogle, S. M.; Paustian, K.; Zhang, Y.; Kent, J.; Gurung, R.; Klotz, R.

2016-12-01

Agricultural lands occur across a variety of landscapes in the United States, and carbon dynamics are largely controlled by management decisions along with edaphic characteristics, climate and other environmental drivers. Due to the influence of management, there is potential to sequester carbon in soils with adoption of conservation practices, such as setting aside degraded land from production, limiting tillage disturbance, enhancing crop production with higher yielding varieties, planting cover crops, and restoring wetlands where they have been drained for crop production. In 2010, the level of sequestration in mineral soils across US croplands was 48 million metric tonnes CO2 equivalent, which is down from the high during the past 25 years of 90 million metric tonnes CO2 equivalent. In contrast, drained wetlands that are used for crop production were emitting 22.1 million metric tonnes CO2 equivalent in 2010. In the short term, restoring drained wetlands would decrease CO2emissions to the atmosphere, and even with the additional CH4 emissions from restored wetlands, there would an overall reduction in greenhouse gas emissions from these lands. In turn, this would make a significant contribution to the USDA Climate Smart Agriculture Plan for reducing greenhouse gas emissions by 120 million metric tonnes CO2 equivalent in support of the Paris Agreement. The potential to sequester carbon in the future will also be impacted by climate change, in addition to the management decisions of land managers. We simulated future carbon dynamics through 2060 based on climate change projections for RCP 2.5, 4.5 and 8.5 scenarios, with and without CO2 fertilization effects. We are using the results as input to a general equilibrium model for the agricultural economic sector to better understand the economic consequences of climate change and the potential for greenhouse gas mitigation. By evaluating the influence of climate change and economic welfare, our study is providing a basis to understand the potential long-term contribution of carbon sequestration in support of a Climate Smart Agriculture Program in the United States.

Control of Fossil-Fuel Particulate Black Carbon and Organic Matter, the Most Effective Method of Slowing Global Warming

NASA Astrophysics Data System (ADS)

Jacobson, M. Z.

2001-12-01

Under the 1997 Kyoto Protocol, no control of black carbon (BC) was considered. Here, it is found, through simulations in which seven new particles feedbacks to climate are identified, that any emission reduction of fossil-fuel (f.f.) particulate BC plus associated organic matter (OM) will slow global warming more than will any emission reduction of CO2 or CH4 for a definite time period. When all f.f. BC+OM and anthropogenic CO2 and CH4 emissions are eliminated together, that period is 20-90 years. It is also found that historical net global warming can be attributed roughly to greenhouse-gas plus f.f. BC+OM warming minus anthropogenic sulfate cooling. Eliminating all f.f. BC+OM could eliminate more than 40 percent of such net warming within three years if no other changes occurred. Reducing CO2 emissions by a third would have the same effect, but after 50-200 years. Finally, diesel cars warm climate more than do equivalent gasoline cars; thus, fuel- and carbon-tax laws that favor diesel promote global warming.

40 CFR 61.353 - Alternative means of emission limitation.

Code of Federal Regulations, 2010 CFR

2010-07-01

... for Benzene Waste Operations § 61.353 Alternative means of emission limitation. (a) If, in the Administrator's judgment, an alternative means of emission limitation will achieve a reduction in benzene emissions at least equivalent to the reduction in benzene emissions from the source achieved by the...

Global time trends in PAH emissions from motor vehicles

PubMed Central

Shen, Huizhong; Tao, Shu; Wang, Rong; Wang, Bin; Shen, Guofeng; Li, Wei; Su, Shenshen; Huang, Ye; Wang, Xilong; Liu, Wenxin; Li, Bengang; Sun, Kang

2013-01-01

Emission from motor vehicles is the most important source of polycyclic aromatic hydrocarbons (PAHs) in urban areas. Emission factors of individual PAHs for motor vehicles reported in the literature varied 4 to 5 orders of magnitude, leading to high uncertainty in emission inventory. In this study, key factors affecting emission factors of PAHs (EFPAH) for motor vehicles were evaluated quantitatively based on thousands of EFPAH measured in 16 countries for over 50 years. The result was used to develop a global emission inventory of PAHs from motor vehicles. It was found that country and vehicle model year are the most important factors affecting EFPAH, which can be quantified using a monovariate regression model with per capita gross domestic production (purchasing power parity) as a sole independent variable. On average, 29% of variation in log-transformed EFPAH could be explained by the model, which was equivalent to 90% reduction in overall uncertainty on arithmetic scale. The model was used to predict EFPAH and subsequently PAH emissions from motor vehicles for various countries in the world during a period from 1971 to 2030. It was estimated that the global emission reached its peak value of approximate 101 Gg in 1978 and decreased afterwards due to emission control in developed countries. The annual emission picked up again since 1990 owing to accelerated energy consumption in China and other developing countries. With more and more rigid control measures taken in the developing world, global emission of PAHs is currently passing its second peak. It was predicted that the emission would decrease from 77 Gg in 2010 to 42 Gg in 2030. PMID:24198716

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.

The Relationship Between Stellar Populations and Lyα Emission in Lyman Break Galaxies

NASA Astrophysics Data System (ADS)

Kornei, Katherine; Shapley, A. E.; Erb, D. K.; Steidel, C. C.; Reddy, N. A.; Pettini, M.; Bogosavljevic, M.

2010-01-01

We present the results of a photometric and spectroscopic survey of 321 Lyman break galaxies (LBGs) at z ˜ 3 to investigate systematically the relationship between Lyα emission and stellar populations. Lyα equivalent widths (EWs) were calculated from rest-frame UV spectroscopy and optical/near-infrared/Spitzer photometry was used in population synthesis modeling to derive the key properties of age, dust extinction, star formation rate (SFR), and stellar mass. We directly compare the stellar populations of LBGs with and without strong Lyα emission, where we designate the former group (EW ≥ 20 angstroms) as Lyα-emitters (LAEs) and the latter group (EW < 20 angstroms) as non-LAEs. This controlled method of comparing objects from the same UV luminosity distribution represents an improvement over previous studies in which the stellar populations of LBGs and narrowband-selected LAEs were contrasted, where the latter were often intrinsically fainter in broadband filters by an order of magnitude simply due to different selection criteria. Using a variety of statistical tests, we find that Lyα equivalent width and age, SFR, and dust extinction, respectively, are significantly correlated in the sense that objects with strong Lyα emission also tend to be older, lower in star formation rate, and less dusty than objects with weak Lyα emission, or the line in absorption. We accordingly conclude that, within the LBG sample, objects with strong Lyα emission represent a later stage of galaxy evolution in which supernovae-induced outflows have reduced the dust covering fraction. We also examined the hypothesis that the attenuation of Lyα photons is lower than that of the continuum, as proposed by some, but found no evidence to support this picture.

Recycling of wood for particle board production: accounting of greenhouse gases and global warming contributions.

PubMed

Merrild, Hanna; Christensen, Thomas H

2009-11-01

The greenhouse gas (GHG) emissions related to the recycling of wood waste have been assessed with the purpose to provide useful data that can be used in accounting of greenhouse gas emissions. Here we present data related to the activities in a material recovery facility (MRF) where wood waste is shredded and foreign objects are removed in order to produce wood chips for use in the production of particleboard. The data are presented in accordance with the UOD (upstream, operational, downstream) framework presented in Gentil et al. (Waste Management & Research, 27, 2009). The GHG accounting shows that the emissions related to upstream activities (5 to 41 kg CO(2)-equivalents tonne( -1) wood waste) and to activities at the MRF (approximately 5 kg CO(2)-equivalents tonne(-1) wood waste) are negligible compared to the downstream processing (-560 to -120 kg CO(2)equivalents tonne(-1) wood waste). The magnitude of the savings in GHG emissions downstream are mainly related to savings in energy consumption for drying of fresh wood for particleboard production. However, the GHG account highly depends on the choices made in the modelling of the downstream system. The inclusion of saved electricity from avoided chipping of virgin wood does not change the results radically (-665 to -125 kg CO(2)-equivalents tonne(- 1) wood waste). However, if in addition it is assumed that the GHG emissions from combustion of wood has no global warming potential (GWP) and that the energy produced from excess wood due to recycling substitutes energy from fossil fuels, here assumed to be coal, potentially large downstream GHG emissions savings can be achieved by recycling of waste wood (-1.9 to -1.3 tonnes CO(2)-equivalents tonne(- 1) wood waste). As the data ranges are broad, it is necessary to carefully evaluate the feasibility of the data in the specific system which the GHG accounting is to be applied to.

Subpart H: National Emission Standards for Emissions of Radionuclides Other Than Radon From Department of Energy Facilities

EPA Pesticide Factsheets

Subpart H sets a limit on the emission of radionuclides that ensures no member of the public receives an effective dose equivalent of more than 10 mrem/year emissions from Department of Energy (DOE) facilities.

40 CFR 86.1804-01 - Acronyms and abbreviations.

Code of Federal Regulations, 2012 CFR

2012-07-01

...—Nonmethane Hydrocarbons. NMHCE—Non-Methane Hydrocarbon Equivalent. NMOG—Non-methane organic gases. NO—nitric....—Degree(s). DNPH—2,4-dinitrophenylhydrazine. EDV—Emission Data Vehicle. EP—End point. ETW—Equivalent test...—dispensed fuel temperature. THC—Total Hydrocarbons. THCE—Total Hydrocarbon Equivalent. TLEV—Transitional Low...

40 CFR 86.1804-01 - Acronyms and abbreviations.

Code of Federal Regulations, 2014 CFR

2014-07-01

...—Nonmethane Hydrocarbons. NMHCE—Non-Methane Hydrocarbon Equivalent. NMOG—Non-methane organic gases. NO—nitric....—Degree(s). DNPH—2,4-dinitrophenylhydrazine. EDV—Emission Data Vehicle. EP—End point. ETW—Equivalent test...—dispensed fuel temperature. THC—Total Hydrocarbons. THCE—Total Hydrocarbon Equivalent. TLEV—Transitional Low...

Tier 2 Intermediate Useful Life (50,000 Miles) and 4000 Mile Supplemental Federal Test Procedure (SFTP) Exhaust Emission Results for a NOx Adsorber and Diesel Particle Filter Equipped Light-Duty Diesel Vehicle

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

Tatur, M.; Tyrer, H.; Tomazic, D.

2005-01-01

Due to its high efficiency and superior durability the diesel engine is again becoming a prime candidate for future light-duty vehicle applications within the United States. While in Europe the overall diesel share exceeds 40%, the current diesel share in the U.S. is 1%. Despite the current situation and the very stringent Tier 2 emission standards, efforts are being made to introduce the diesel engine back into the U.S. market. In order to succeed, these vehicles have to comply with emissions standards over a 120,000 miles distance while maintaining their excellent fuel economy. The availability of technologies such as high-pressure,more » common-rail fuel systems, low-sulfur diesel fuel, NO{sub x} adsorber catalysts (NAC), and diesel particle filters (DPFs) allow the development of powertrain systems that have the potential to comply with the light-duty Tier 2 emission requirements. In support of this, the U.S. Department of Energy (DOE) has engaged in several test projects under the Advanced Petroleum Based Fuels - Diesel Emission Controls (APBF-DEC) activity. The primary technology being addressed by these projects are the sulfur tolerance and durability of the NAC/DPF system. The project investigated the performance of the emission control system and system desulphurization effects on regulated and unregulated emissions. Emissions measurements were conducted over the Federal Test Procedure (FTP), Supplemental Federal Test Procedure (SFTP), and the Highway Fuel Economy Test (HFET). Testing was conducted after the accumulation of 150 hours of engine operation calculated to be the equivalent of approximately 8,200 miles. For these evaluations three out of six of the FTP test cycles were within the 50,000-mile Tier 2 bin 5 emission standards (0.05 g/mi NO{sub x} and 0.01 g/mi PM). Emissions over the SC03 portion of the SFTP were within the 4,000-mile SFTP standards. The emission of NO{sub x}+NMHC exceeded the 4,000-mile standard over the US06 portion of the SFTP. Testing was also conducted after the accumulation of 1,000 hours of engine operation calculated to be the equivalent of approximately 50,000 miles. Recalibrated driveability maps resulted in more repeatable NOs{sub x} emissions from cycle to cycle. The NO{sub x} level was below the Tier 2 emission limits for 50,000 and 120,000 miles. NMHC emissions were found at a level outside the limit for 120,000 miles.« less

Global Air Quality and Climate Impacts of Mitigating Short-lived Climate Pollution in China

NASA Astrophysics Data System (ADS)

Harper, K.; Unger, N.; Heyes, C.; Kiesewetter, G.; Klimont, Z.; Schoepp, W.; Wagner, F.

2014-12-01

China is a major emitter of harmful air pollutants, including the short-lived climate pollutants (SLCPs) and their precursors. Implementation of pollution control technologies provides a mechanism for simultaneously protecting human and ecosystem health and achieving near-term climate co-benefits; however, predicting the outcomes of technical and policy interventions is challenging because the SLCPs participate in both climate warming and cooling and share many common emission sources. Here, we present the results of a combined regional integrated assessment and global climate modeling study aimed at quantifying the near-term climate and air quality co-benefits of selective control of Chinese air pollution emissions. Results from IIASA's Greenhouse Gas - Air Pollution Interactions and Synergies (GAINS) integrated assessment model indicate that methane emission reductions make up > 75% of possible CO2-equivalent emission reductions of the SLCPs and their precursors in China in 2030. A multi-pollutant emission reduction scenario incorporating the 2030 Chinese pollution control measures with the highest potential for future climate impact is applied to the NASA ModelE2 - Yale Interactive Terrestrial Biosphere (NASA ModelE2-YIBs) global carbon - chemistry - climate model to assess the regional and long-range impacts of Chinese SLCP mitigation measures. Using model simulations that incorporate dynamic methane emissions and photosynthesis-dependent isoprene emissions, we quantify the impacts of Chinese reductions of the short-lived air pollutants on radiative forcing and on surface ozone and particulate air pollution. Present-day modeled methane mole fractions are evaluated against SCIAMACHY methane columns and NOAA ESRL/GMD surface flask measurements.

The impact of municipal solid waste treatment methods on greenhouse gas emissions in Lahore, Pakistan

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

Batool, Syeda Adila; Chuadhry, Muhammad Nawaz

2009-01-15

The contribution of existing municipal solid waste management to emission of greenhouse gases and the alternative scenarios to reduce emissions were analyzed for Data Ganj Bukhsh Town (DGBT) in Lahore, Pakistan using the life cycle assessment methodology. DGBT has a population of 1,624,169 people living in 232,024 dwellings. Total waste generated is 500,000 tons per year with an average per capita rate of 0.84 kg per day. Alternative scenarios were developed and evaluated according to the environmental, economic, and social atmosphere of the study area. Solid waste management options considered include the collection and transportation of waste, collection of recyclablesmore » with single and mixed material bank container systems (SMBCS, MMBCS), material recovery facilities (MRF), composting, biogasification and landfilling. A life cycle inventory (LCI) of the six scenarios along with the baseline scenario was completed; this helped to quantify the CO{sub 2} equivalents, emitted and avoided, for energy consumption, production, fuel consumption, and methane (CH{sub 4}) emissions. LCI results showed that the contribution of the baseline scenario to the global warming potential as CO{sub 2} equivalents was a maximum of 838,116 tons. The sixth scenario had a maximum reduction of GHG emissions in terms of CO{sub 2} equivalents of -33,773 tons, but the most workable scenario for the current situation in the study area is scenario 5. It saves 25% in CO{sub 2} equivalents compared to the baseline scenario.« less

Environmental and economic evaluation of bioenergy in Ontario, Canada.

PubMed

Zhang, Yimin; Habibi, Shiva; MacLean, Heather L

2007-08-01

We examined life cycle environmental and economic implications of two near-term scenarios for converting cellulosic biomass to energy, generating electricity from cofiring biomass in existing coal power plants, and producing ethanol from biomass in stand-alone facilities in Ontario, Canada. The study inventories near-term biomass supply in the province, quantifies environmental metrics associated with the use of agricultural residues for producing electricity and ethanol, determines the incremental costs of switching from fossil fuels to biomass, and compares the cost-effectiveness of greenhouse gas (GHG) and air pollutant emissions abatement achieved through the use of the bioenergy. Implementing a biomass cofiring rate of 10% in existing coal-fired power plants would reduce annual GHG emissions by 2.3 million metric tons (t) of CO2 equivalent (7% of the province's coal power plant emissions). The substitution of gasoline with ethanol/gasoline blends would reduce annual provincial lightduty vehicle fleet emissions between 1.3 and 2.5 million t of CO2 equivalent (3.5-7% of fleet emissions). If biomass sources other than agricultural residues were used, additional emissions reductions could be realized. At current crude oil prices ($70/barrel) and levels of technology development of the bioenergy alternatives, the biomass electricity cofiring scenario analyzed is more cost-effective for mitigating GHG emissions ($22/t of CO2 equivalent for a 10% cofiring rate) than the stand-alone ethanol production scenario ($92/t of CO2 equivalent). The economics of biomass cofiring benefits from existing capital, whereas the cellulosic ethanol scenario does not. Notwithstanding this result, there are several factors that increase the attractiveness of ethanol. These include uncertainty in crude oil prices, potential for marked improvements in cellulosic ethanol technology and economics, the province's commitment to 5% ethanol content in gasoline, the possibility of ethanol production benefiting from existing capital, and there being few alternatives for moderate-to-large-scale GHG emissions reductions in the transportation sector.

Quantifying greenhouse gas emissions from coal fires using airborne and ground-based methods

USGS Publications Warehouse

Engle, M.A.; Radke, L.F.; Heffern, E.L.; O'Keefe, J.M.K.; Smeltzer, C.D.; Hower, J.C.; Hower, J.M.; Prakash, A.; Kolker, A.; Eatwell, R.J.; ter, Schure A.; Queen, G.; Aggen, K.L.; Stracher, G.B.; Henke, K.R.; Olea, R.A.; Roman-Colon, Y.

2011-01-01

Coal fires occur in all coal-bearing regions of the world and number, conservatively, in the thousands. These fires emit a variety of compounds including greenhouse gases. However, the magnitude of the contribution of combustion gases from coal fires to the environment is highly uncertain, because adequate data and methods for assessing emissions are lacking. This study demonstrates the ability to estimate CO2 and CH4 emissions for the Welch Ranch coal fire, Powder River Basin, Wyoming, USA, using two independent methods: (a) heat flux calculated from aerial thermal infrared imaging (3.7-4.4td-1 of CO2 equivalent emissions) and (b) direct, ground-based measurements (7.3-9.5td-1 of CO2 equivalent emissions). Both approaches offer the potential for conducting inventories of coal fires to assess their gas emissions and to evaluate and prioritize fires for mitigation. ?? 2011.

Quantifying greenhouse gas emissions from coal fires using airborne and ground-based methods

USGS Publications Warehouse

Engle, Mark A.; Radke, Lawrence F.; Heffern, Edward L.; O'Keefe, Jennifer M.K.; Smeltzer, Charles; Hower, James C.; Hower, Judith M.; Prakash, Anupma; Kolker, Allan; Eatwell, Robert J.; ter Schure, Arnout; Queen, Gerald; Aggen, Kerry L.; Stracher, Glenn B.; Henke, Kevin R.; Olea, Ricardo A.; Román-Colón, Yomayara

2011-01-01

Coal fires occur in all coal-bearing regions of the world and number, conservatively, in the thousands. These fires emit a variety of compounds including greenhouse gases. However, the magnitude of the contribution of combustion gases from coal fires to the environment is highly uncertain, because adequate data and methods for assessing emissions are lacking. This study demonstrates the ability to estimate CO2 and CH4 emissions for the Welch Ranch coal fire, Powder River Basin, Wyoming, USA, using two independent methods: (a) heat flux calculated from aerial thermal infrared imaging (3.7–4.4 t d−1 of CO2 equivalent emissions) and (b) direct, ground-based measurements (7.3–9.5 t d−1 of CO2 equivalent emissions). Both approaches offer the potential for conducting inventories of coal fires to assess their gas emissions and to evaluate and prioritize fires for mitigation.

On-road and laboratory emissions of NO, NO2, NH3, N2O and CH4 from late-model EU light utility vehicles: Comparison of diesel and CNG.

PubMed

Vojtíšek-Lom, Michal; Beránek, Vít; Klír, Vojtěch; Jindra, Petr; Pechout, Martin; Voříšek, Tomáš

2018-03-01

Exhaust emissions of eight Euro 6 light duty vehicles - two station wagons and six vans - half powered by diesel fuel and half by compressed natural gas (CNG) were examined using both chassis dynamometer and on-road testing. A portable on-board FTIR analyzer was used to measure concentrations of reactive nitrogen compounds - NO, NO 2 and ammonia, of CO, formaldehyde, acetaldehyde and greenhouse gases CO 2 , methane and N 2 O. Exhaust flow was inferred from engine control unit data. Total emissions per cycle were compared and found to be in good agreement with laboratory measurements of NO X , CO and CO 2 during dynamometer tests. On diesel engines, mean NO X emissions were 136-1070mg/km in the laboratory and 537-615mg/km on the road, in many cases nearly an order of magnitude higher compared to the numerical value of the Euro 6 limit. Mean N 2 O emissions were 3-19mg/km and were equivalent to several g/km CO 2 . The measurements suggest that NO X and N 2 O emissions from late-model European light utility vehicles with diesel engines are non-negligible and should be continuously assessed and scrutinized. High variances in NO X emissions among the tested diesel vehicles suggest that large number of vehicles should be tested to offer at least some insights about distribution of fleet emissions among vehicles. CNG engines exhibited relatively low emissions of NO X (12-186mg/km) and NH 3 (10-24mg/km), while mean emissions of methane were 18-45mg/km, under 1g/km CO 2 equivalent, and N 2 O, CO, formaldehyde and acetaldehyde were negligible. The combination of a relatively clean-burning fuel, modern engine technology and a three-way catalyst has resulted in relatively low emissions under the wide variety of operating conditions encountered during the tests. The on-board FTIR has proven to be a useful instrument capable of covering, with the exception of total hydrocarbons, essentially all gaseous pollutants of interest. Copyright © 2017 Elsevier B.V. All rights reserved.

Net emissions of CH4 and CO2 in Alaska: Implications for the region's greenhouse gas budget

USGS Publications Warehouse

Zhuang, Q.; Melillo, J.M.; McGuire, A.D.; Kicklighter, D.W.; Prinn, R.G.; Steudler, P.A.; Felzer, B.S.; Hu, S.

2007-01-01

We used a biogeochemistry model, the Terrestrial Ecosystem Model (TEM), to study the net methane (CH4) fluxes between Alaskan ecosystems and the atmosphere. We estimated that the current net emissions of CH4 (emissions minus consumption) from Alaskan soils are ???3 Tg CH 4/yr. Wet tundra ecosystems are responsible for 75% of the region's net emissions, while dry tundra and upland boreal forests are responsible for 50% and 45% of total consumption over the region, respectively. In response to climate change over the 21st century, our simulations indicated that CH 4 emissions from wet soils would be enhanced more than consumption by dry soils of tundra and boreal forests. As a consequence, we projected that net CH4 emissions will almost double by the end of the century in response to high-latitude warming and associated climate changes. When we placed these CH4 emissions in the context of the projected carbon budget (carbon dioxide [CO2] and CH4) for Alaska at the end of the 21st century, we estimated that Alaska will be a net source of greenhouse gases to the atmosphere of 69 Tg CO2 equivalents/yr, that is, a balance between net methane emissions of 131 Tg CO2 equivalents/yr and carbon sequestration of 17 Tg C/yr (62 Tg CO2 equivalents/yr). ?? 2007 by the Ecological Society of America.

2004 Methane and Nitrous Oxide Emissions from Manure Management in South Africa

PubMed Central

Moeletsi, Mokhele Edmond; Tongwane, Mphethe Isaac

2015-01-01

Simple Summary Livestock manure management is one of the main sources of greenhouse gas (GHG) emissions in South Africa producing mainly methane and nitrous oxide. The emissions from this sub-category are dependent on how manure is stored. Liquid-stored manure predominantly produces methane while dry-based manure enhances mainly production of nitrous oxide. Intergovernmental Panel on Climate Change (IPCC) guidelines were utilized at different tier levels in estimating GHG emissions from manure management. The results show that methane emissions are relatively higher than nitrous oxide emissions with 3104 Gg and 2272 Gg respectively in carbon dioxide global warming equivalent. Abstract Manure management in livestock makes a significant contribution towards greenhouse gas emissions in the Agriculture; Forestry and Other Land Use category in South Africa. Methane and nitrous oxide emissions are prevalent in contrasting manure management systems; promoting anaerobic and aerobic conditions respectively. In this paper; both Tier 1 and modified Tier 2 approaches of the IPCC guidelines are utilized to estimate the emissions from South African livestock manure management. Activity data (animal population, animal weights, manure management systems, etc.) were sourced from various resources for estimation of both emissions factors and emissions of methane and nitrous oxide. The results show relatively high methane emissions factors from manure management for mature female dairy cattle (40.98 kg/year/animal), sows (25.23 kg/year/animal) and boars (25.23 kg/year/animal). Hence, contributions for pig farming and dairy cattle are the highest at 54.50 Gg and 32.01 Gg respectively, with total emissions of 134.97 Gg (3104 Gg CO2 Equivalent). Total nitrous oxide emissions are estimated at 7.10 Gg (2272 Gg CO2 Equivalent) and the three main contributors are commercial beef cattle; poultry and small-scale beef farming at 1.80 Gg; 1.72 Gg and 1.69 Gg respectively. Mitigation options from manure management must be taken with care due to divergent conducive requirements of methane and nitrous oxide emissions requirements. PMID:26479229

The effects of nitrogen fertilization on N2O emissions from a rubber plantation

NASA Astrophysics Data System (ADS)

Zhou, Wen-Jun; Ji, Hong-Li; Zhu, Jing; Zhang, Yi-Ping; Sha, Li-Qing; Liu, Yun-Tong; Zhang, Xiang; Zhao, Wei; Dong, Yu-Xin; Bai, Xiao-Long; Lin, You-Xin; Zhang, Jun-Hui; Zheng, Xun-Hua

2016-06-01

To gain the effects of N fertilizer applications on N2O emissions and local climate change in fertilized rubber (Hevea brasiliensis) plantations in the tropics, we measured N2O fluxes from fertilized (75 kg N ha-1 yr-1) and unfertilized rubber plantations at Xishuangbanna in southwest China over a 2-year period. The N2O emissions from the fertilized and unfertilized plots were 4.0 and 2.5 kg N ha-1 yr-1, respectively, and the N2O emission factor was 1.96%. Soil moisture, soil temperature, and the area weighted mean ammoniacal nitrogen (NH4+-N) content controlled the variations in N2O flux from the fertilized and unfertilized rubber plantations. NH4+-N did not influence temporal changes in N2O emissions from the trench, slope, or terrace plots, but controlled spatial variations in N2O emissions among the treatments. On a unit area basis, the 100-year carbon dioxide equivalence of the fertilized rubber plantation N2O offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local tropical rainforest, respectively. When entire land area in Xishuangbanna is considered, N2O emissions from fertilized rubber plantations offset 17.1% of the tropical rainforest’s carbon sink. The results show that if tropical rainforests are converted to fertilized rubber plantations, regional N2O emissions may enhance local climate warming.

Reducing the Carbon Footprint of Commercial Refrigeration Systems Using Life Cycle Climate Performance Analysis: From System Design to Refrigerant Options

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

Fricke, Brian A; Abdelaziz, Omar; Vineyard, Edward Allan

In this paper, Life Cycle Climate Performance (LCCP) analysis is used to estimate lifetime direct and indirect carbon dioxide equivalent gas emissions of various refrigerant options and commercial refrigeration system designs, including the multiplex DX system with various hydrofluorocarbon (HFC) refrigerants, the HFC/R744 cascade system incorporating a medium-temperature R744 secondary loop, and the transcritical R744 booster system. The results of the LCCP analysis are presented, including the direct and indirect carbon dioxide equivalent emissions for each refrigeration system and refrigerant option. Based on the results of the LCCP analysis, recommendations are given for the selection of low GWP replacement refrigerantsmore » for use in existing commercial refrigeration systems, as well as for the selection of commercial refrigeration system designs with low carbon dioxide equivalent emissions, suitable for new installations.« less

Emissions and Total Energy Consumption of a Multicylinder Piston Engine Running on Gasoline and a Hydrogen-gasoline Mixture

NASA Technical Reports Server (NTRS)

Cassidy, J. F.

1977-01-01

A multicylinder reciprocating engine was used to extend the efficient lean operating range of gasoline by adding hydrogen. Both bottled hydrogen and hydrogen produced by a research methanol steam reformer were used. These results were compared with results for all gasoline. A high-compression-ratio, displacement production engine was used. Apparent flame speed was used to describe the differences in emissions and performance. Therefore, engine emissions and performance, including apparent flame speed and energy lost to the cooling system and the exhaust gas, were measured over a range of equivalence ratios for each fuel. All emission levels decreased at the leaner conditions. Adding hydrogen significantly increased flame speed over all equivalence ratios.

Global time trends in PAH emissions from motor vehicles

NASA Astrophysics Data System (ADS)

Shen, Huizhong; Tao, Shu; Wang, Rong; Wang, Bin; Shen, Guofeng; Li, Wei; Su, Shenshen; Huang, Ye; Wang, Xilong; Liu, Wenxin; Li, Bengang; Sun, Kang

2011-04-01

Emission from motor vehicles is the most important source of polycyclic aromatic hydrocarbons (PAHs) in urban areas. Emission factors of individual PAHs for motor vehicles reported in the literature varied 4 to 5 orders of magnitude, leading to high uncertainty in emission inventory. In this study, key factors affecting emission factors of PAHs (EF PAH) for motor vehicles were evaluated quantitatively based on thousands of EF PAH measured in 16 countries for over 50 years. The result was used to develop a global emission inventory of PAHs from motor vehicles. It was found that country and vehicle model year are the most important factors affecting EF PAH, which can be quantified using a monovariate regression model with per capita gross domestic production (purchasing power parity) as a sole independent variable. On average, 29% of variation in log-transformed EF PAH could be explained by the model, which was equivalent to 90% reduction in overall uncertainty on arithmetic scale. The model was used to predict EF PAH and subsequently PAH emissions from motor vehicles for various countries in the world during a period from 1971 to 2030. It was estimated that the global emission reached its peak value of approximate 101 Gg in 1978 and decreased afterwards due to emission control in developed countries. The annual emission picked up again since 1990 owing to accelerated energy consumption in China and other developing countries. With more and more rigid control measures taken in the developing world, global emission of PAHs is currently passing its second peak. It was predicted that the emission would decrease from 77 Gg in 2010 to 42 Gg in 2030.

Emission Inventory of Halogenated greenhouse gases in China during 1980-2050

NASA Astrophysics Data System (ADS)

Fang, X.; Velders, G. J. M.; Ravishankara, A. R.; Molina, M.; Su, S.; Zhang, J.; Zhou, X.; Hu, J.; Prinn, R. G.

2015-12-01

China is currently the largest producer and consumer of ozone-depleting substances (ODSs) which are regulated by the Montreal Protocol (MP). Many ODSs are also powerful greenhouse gases (GHGs). The Multilateral Fund has subsidized ~1 billion US dollars for the ODS phase out in China, and thus the return on this investment is of great interest. This study gives a comprehensive emission inventory in China from 1980 to 2013 of halocarbons including ODSs and their alternatives, the hydrofluorocarbons (HFCs) that are also greenhouse gases. We then project these emissions up to 2050 according to the MP and several policy options. Total emissions of ODS and HFCs were estimated to be ~500 CO2-eq Tg/yr in 2013 which are equivalent to ~5% of total GHG emissions in China including fossil fuel CO2 emissions. Our estimate shows that China has succeeded in substantially reducing CFC-11-equivalent emissions (to protect the ozone layer), and CO2-equivalent emissions (to protect climate) of ODSs since the mid-1990s when their phase out started in China in compliance with the MP. Furthermore, the avoided CO2-eq emissions due to compliance with the MP are even greater compared to the reduced emissions, for example net cumulative avoided emissions during 19 year period between 1995-2013 are comparable to the current one year CO2 emissions from fossil fuels in China. We find that HFC CO2-eq emissions increased rapidly in last decade, which make up ~2% in 2005 to ~20% of total halocarbon CO2-eq emissions in 2013. Under a baseline scenario in which HFCs are used as alternatives in the ongoing phase out of HCFCs in China, emissions of HFCs are predicted to be important components of both China's and global future GHG emissions. However, potential exists for minimizing China's HFC emissions under mitigation scenarios. Our conclusions about China's past and future ODS and HFC emission trajectories are likely to apply to other developing countries, with important implications for mitigating global GHG emissions.

Recycling of metals: accounting of greenhouse gases and global warming contributions.

PubMed

Damgaard, Anders; Larsen, Anna W; Christensen, Thomas H

2009-11-01

Greenhouse gas (GHG) emissions related to recycling of metals in post-consumer waste are assessed from a waste management perspective; here the material recovery facility (MRF), for the sorting of the recovered metal. The GHG accounting includes indirect upstream emissions, direct activities at the MRF as well as indirect downstream activities in terms of reprocessing of the metal scrap and savings in terms of avoided production of virgin metal. The global warming factor (GWF) shows that upstream activities and the MRF causes negligible GHG emissions (12.8 to 52.6 kg CO(2)-equivalents tonne(-1) recovered metal) compared to the reprocessing of the metal itself (360-1260 kg CO(2)-equivalents tonne(-1) of recovered aluminium and 400- 1020 kg CO(2)-equivalents tonne(- 1) of recovered steel).The reprocessing is however counterbalanced by large savings of avoided virgin production of steel and aluminium. The net downstream savings were found to be 5040-19 340 kg CO(2)-equivalents tonne(-1) of treated aluminium and 560-2360 kg CO(2)-equivalents tonne(-1) of treated steel. Due to the huge differences in reported data it is hard to compare general data on the recovery of metal scrap as they are very dependent on the technology and data choices. Furthermore, the energy used in both the recovery process as well as the avoided primary production is crucial. The range of avoided impact shows that recovery of metals will always be beneficial over primary production, due to the high energy savings, and that the GHG emissions associated with the sorting of metals are negligible.

On the Lack of Correlation Between Mg II 2796, 2803 Angstrom and Lyman alpha Emission in Lensed Star-Forming Galaxies

NASA Technical Reports Server (NTRS)

Rigby, Jane Rebecca; Bayliss, M. B.; Gladders, M. D.; Sharon, K.; Wuyts, E.; Dahle, H.

2014-01-01

We examine the Mg II 2796, 2803 Angstrom, Lyman alpha, and nebular line emission in five bright star-forming galaxies at 1.66 less than z less than 1.91 that have been gravitationally lensed by foreground galaxy clusters. All five galaxies show prominent Mg II emission and absorption in a P Cygni profile. We find no correlation between the equivalent widths of Mg II and Lyman alpha emission. The Mg II emission has a broader range of velocities than do the nebular emission line profiles; the Mg II emission is redshifted with respect to systemic by 100 to 200 km s(exp-1). When present, Lyman alpha is even more redshifted. The reddest components of Mg II and Lyman alpha emission have tails to 500-600 km s(exp-1), implying a strong outflow. The lack of correlation in the Mg II and Lyman alpha equivalent widths, the differing velocity profiles, and the high ratios of Mg II to nebular line fluxes together suggest that the bulk of Mg II emission does not ultimately arise as nebular line emission, but may instead be reprocessed stellar continuum emission.

Root-Associated Methane Oxidation and Methanogenesis: Key Determinants of Wetland Methane Emissions

NASA Technical Reports Server (NTRS)

King, G. M.

1997-01-01

During the award period, we have assessed the extent and controls of methane oxidation in north temperate wetlands. It is evident that wetlands have been a major global source of atmospheric methane in the past, and are so at present. It is also evident that microbial methane oxidation consumes a variable fraction of total wetland methane production, perhaps 10%-90%. Methane oxidation is thus a potentially important control of wetland methane emission. Our efforts have been designed to determine the extent of the process, its controls, and possible relationships to changes that might be expected in wetlands as a consequence of anthropogenic or climate-related disturbances. Current work, has emphasized controls of methane oxidation associated with rooted aquatic plants. As for the sediment-water interface, we have observed that oxygen availability is a primary limiting factor. Our conclusion is based on several different lines of evidence obtained from in vitro and in situ analyses. First, we have measured the kinetics of methane oxidation by intact plant roots harboring methane-oxidizing bacteria, as well as the kinetics of the methanotrophs themselves. Values for the half-saturation constant (apparent K(sub m)) are approximately 5 microns. These values are roughly equivalent to, or much less than porewater methane concentrations, indicating that uptake is likely saturated with respect to methane, and that some other parameter must limit activity. Methane concentrations in the lacunar spaces at the base of plant stems are also comparable to the half-saturation constants (when expressed as equivalent dissolved concentrations), providing further support for limitation of uptake by parameters other than methane.

Energy and air emission effects of water supply.

PubMed

Stokes, Jennifer R; Horvath, Arpad

2009-04-15

Life-cycle air emission effects of supplying water are explored using a hybrid life-cycle assessment For the typically sized U.S. utility analyzed, recycled water is preferable to desalination and comparable to importation. Seawater desalination has an energy and air emission footprint that is 1.5-2.4 times larger than that of imported water. However, some desalination modes fare better; brackish groundwater is 53-66% as environmentally intensive as seawater desalination. The annual water needs (326 m3) of a typical Californian that is met with imported water requires 5.8 GJ of energy and creates 360 kg of CO2 equivalent emissions. With seawater desalination, energy use would increase to 14 GJ and 800 kg of CO2 equivalent emissions. Meeting the water demand of California with desalination would consume 52% of the state's electricity. Supply options were reassessed using alternative electricity mixes, including the average mix of the United States and several renewable sources. Desalination using solar thermal energy has lower greenhouse gas emissions than that of imported and recycled water (using California's electricity mix), but using the U.S. mix increases the environmental footprint by 1.5 times. A comparison with a more energy-intensive international scenario shows that CO2 equivalent emissions for desalination in Dubai are 1.6 times larger than in California. The methods, decision support tool (WEST), and results of this study should persuade decision makers to make informed water policy choices by including energy consumption and material use effects in the decision-making process.

N2O emissions in tropical rainforest and rubber plantation, the indicator from landuse changing in Xishuangbanna, Southwest China

NASA Astrophysics Data System (ADS)

Zhou, W. J.; Zhu, J.; Ji, H. L.; Zhang, Y.; Zhang, J.; Zheng, X.

2016-12-01

To understand the effects of landuse on N2O emissions and local climate change in the tropics, we measured N2O fluxes from a primary tropical rainforest (TRF, with treatments of litter removal and control) and a fertilized rubber plantation (RP, with treatments of fertilization (75 kg N ha-1 yr-1) and unfertilization) at Xishuangbanna, southwest China since 2012. The results have shown: 1) Fertilized RP N2O emission is bimodel, one peak after dry season fertilizer, another after rainy season fertilizer. Otherwise, the unfertilized RP and TRF have the similar seasonal dynamic with one peak in the middle of rainy season. 2) due to the fertilizer influence, the poaitive correlation between soil temperature/soil moisture and N2O was more significantly in unfertilized RP than fertilized RP respectively litter input changed the dominated controller of N2O emission in TRF: litter carbon input and soil DOC content for control treatment and, soil temperature and soil NO3- -N for litter removal treatment. 3) lab incubation indicated denitrification and nitrification as the main source for N2O emission in TRF and RP, respectively. 4) The N2O emissions from the fertilized and unfertilized plots in RP were 4.0 and 2.5 kg N ha-1 yr-1, respectively, from control and litter removal plots in TRF were 0.48 and 0.32 kg N ha-1 yr-1,respectively. 5) 100-year carbon dioxide equivalence of N2O from fertilized RP offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local TRF, respectively. Upscaling it to the whole Xishuangbanna, N2O emissions from fertilized RP offset 17.1% of the tropical rainforest's carbon sink. When tropical rainforests are converted to fertilized rubber plantations, the N2O emission seasonal dynamic and mechanisms changed, the global warming effect is enhanced.

N2O emissions in tropical rainforest and rubber plantation, the indicator from landuse changing in Xishuangbanna, Southwest China

NASA Astrophysics Data System (ADS)

Zhou, Wenjun; Zhu, Jing; Ji, Hong-li; Zhang, Yi-Ping; Sha, Li-Qing; Gao, Jin-Bo; Zhang, Jun-Hui; Zheng, Xunhua

2017-04-01

To understand the effects of landuse on N2O emissions and local climate change in the tropics, we measured N2O fluxes from a primary tropical rainforest (TRF, with treatments of litter removal and control) and a fertilized rubber plantation (RP, with treatments of fertilization (75 kg N ha-1 yr-1) and unfertilization) at Xishuangbanna, southwest China since 2012. The results have shown: 1) Fertilized RP N2O emission is bimodel, one peak after dry season fertilizer, another after rainy season fertilizer. Otherwise, the unfertilized RP and TRF have the similar seasonal dynamic with one peak in the middle of rainy season. 2) due to the fertilizer influence, the poaitive correlation between soil temperature/soil moisture and N2O was more significantly in unfertilized RP than fertilized RP respectively litter input changed the dominated controller of N2O emission in TRF: litter carbon input and soil DOC content for control treatment and, soil temperature and soil NO3- -N for litter removal treatment. 3) lab incubation indicated denitrification and nitrification as the main source for N2O emission in TRF and RP, respectively. 4) The N2O emissions from the fertilized and unfertilized plots in RP were 4.0 and 2.5 kg N ha-1 yr-1, respectively, from control and litter removal plots in TRF were 0.48 and 0.32 kg N ha-1 yr-1,respectively. 5) 100-year carbon dioxide equivalence of N2O from fertilized RP offsets 5.8% and 31.5% of carbon sink of the rubber plantation and local TRF, respectively. Upscaling it to the whole Xishuangbanna, N2O emissions from fertilized RP offset 17.1% of the tropical rainforest's carbon sink. When tropical rainforests are converted to fertilized rubber plantations, the N2O emission seasonal dynamic and mechanisms changed, the global warming effect is enhanced.

Subpart B: National Emission Standards for Radon Emissions From Underground Uranium Mines

EPA Pesticide Factsheets

Subpart B sets a limit on the emission of radon-222 that ensures that no member of the public in any year receives an effective dose equivalent of more than 10 mrem/year from an underground uranium mine.

40 CFR 88.102-94 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... standard. Non-methane Hydrocarbon Equivalent means the sum of the carbon mass emissions of non-oxygenated non-methane hydrocarbons plus the carbon mass emissions of alcohols, aldehydes, or other organic..., expressed as gasoline-fueled vehicle non-methane hydrocarbons. In the case of exhaust emissions, the...

40 CFR 88.102-94 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... standard. Non-methane Hydrocarbon Equivalent means the sum of the carbon mass emissions of non-oxygenated non-methane hydrocarbons plus the carbon mass emissions of alcohols, aldehydes, or other organic..., expressed as gasoline-fueled vehicle non-methane hydrocarbons. In the case of exhaust emissions, the...

40 CFR 88.102-94 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... standard. Non-methane Hydrocarbon Equivalent means the sum of the carbon mass emissions of non-oxygenated non-methane hydrocarbons plus the carbon mass emissions of alcohols, aldehydes, or other organic..., expressed as gasoline-fueled vehicle non-methane hydrocarbons. In the case of exhaust emissions, the...

40 CFR 88.102-94 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... standard. Non-methane Hydrocarbon Equivalent means the sum of the carbon mass emissions of non-oxygenated non-methane hydrocarbons plus the carbon mass emissions of alcohols, aldehydes, or other organic..., expressed as gasoline-fueled vehicle non-methane hydrocarbons. In the case of exhaust emissions, the...

Greenhouse Gas Emissions from Reservoir Water Surfaces: A ...

EPA Pesticide Factsheets

Collectively, reservoirs are an important anthropogenic source of greenhouse gases (GHGs) to the atmosphere. Attempts to model reservoir GHG fluxes, however, have been limited by inconsistencies in methodological approaches and data availability. An increase in the number of published reservoir GHG flux estimates during the last 15 years warrants a comprehensive analysis of the magnitude and potential controls on these fluxes. Here we synthesize worldwide reservoir CH4, CO2, and N2O emission data and estimate that GHG emissions from reservoirs account for 80.2 Tmol CO2 equivalents yr-1, thus constituting approximately 5% of anthropogenic radiative forcing. The majority (93%) of these emissions are from CH4, and mainly in the form of bubbles. While age and latitude have historically been linked to reservoir GHG emissions, we found that factors related to reservoir nutrient status and rainfall were better predictors. In particular, nutrient-rich eutrophic reservoirs were found to have an order of magnitude higher per-area CH4 fluxes, on average, than their nutrient-poor oligotrophic counterparts. Therefore, management measures to reduce reservoir eutrophication may result in an important co-benefit, the reduction of GHG emissions to the atmosphere. Greenhouse gas emissions (GHG)

Calculation of greenhouse gas emissions of jatropha oil and jatropha biodiesel as alternative fuels for electricity production in Côte d'Ivoire

NASA Astrophysics Data System (ADS)

Atta, Pascal Atta; N'guessan, Yao; Morin, Celine; Voirol, Anne Jaecker; Descombes, Georges

2017-02-01

The electricity in Côte d'Ivoire is mainly produced from fossil energy sources. This causes damages on environment due to greenhouse gas emissions (GHG). The aim of this paper is to calculate the greenhouse gas (GHG) emissions of jatropha oil and jatropha biodiesel as alternative fuels for electricity production in Côte d'Ivoire by using Life Cycle Assessment (LCA) methodology. The functional unit in this LCA is defined as 1 kWh of electricity produced by the combustion of jatropha oil or jatropha biodiesel in the engine of a generator. Two scenarios, called short chain and long chain, were examined in this LCA. The results show that 0.132 kg CO2 equivalent is emitted for the scenario 1 with jatropha oil as an alternative fuel against 0.6376 kg CO2 equivalent for the scenario 2 with jatropha biodiesel as an alternative fuel. An 87 % reduction of kg CO2 equivalent is observed in scenario 1 and a 37 % reduction of kg CO2 equivalent is observed in the scenario 2, when compared with a Diesel fuel.

Impact of Active Climate Control Seats on Energy Use, Fuel Use, and CO2 Emissions

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

Kreutzer, Cory J; Rugh, John P; Titov, Eugene V

A project was developed through collaboration between Gentherm and NREL to determine the impact of climate control seats for light-duty vehicles in the United States. The project used a combination of experimentation and analysis, with experimental results providing critical input to the analysis process. First, outdoor stationary vehicle testing was performed at NREL's facility in Golden, CO using multiple occupants. Two pre-production Ford Focus electric vehicles were used for testing; one containing a standard inactive seat and the second vehicle containing a Gentherm climate control seat. Multiple maximum cool-down and steady-state cooling tests were performed in late summer conditions. Themore » two vehicles were used to determine the increase in cabin temperature when using the climate control seat in comparison to the baseline vehicle cabin temperature with a standard seat at the equivalent occupant whole-body sensation. The experiments estimated that on average, the climate control seats allowed for a 2.61 degrees Celsius increase in vehicle cabin temperature at equivalent occupant body sensation compared to the baseline vehicle. The increased cabin air temperature along with their measured energy usage were then used as inputs to the national analysis process. The national analysis process was constructed from full vehicle cabin, HVAC, and propulsion models previously developed by NREL. In addition, three representative vehicle platforms, vehicle usage patterns, and vehicle registration weighted environmental data were integrated into the analysis process. Both the baseline vehicle and the vehicle with climate control seats were simulated, using the experimentally determined cabin temperature offset of 2.61degrees Celsius and added seat energy as inputs to the climate control seat vehicle model. The U.S. composite annual fuel use savings for the climate control seats over the baseline A/C system was determined to be 5.1 gallons of gasoline per year per vehicle, corresponding to 4.0 grams of CO2/mile savings. Finally, the potential impact of 100 percent adoption of climate control seats on U.S. light-duty fleet A/C fuel use was calculated to be 1.3 billion gallons of gasoline annually with a corresponding CO2 emissions reduction of 12.7 million tons. Direct comparison of the impact of the CCS to the ventilated seat off-cycle credit was not possible because the NREL analysis calculated a combined car/truck savings and the baseline A/C CO2 emissions were higher than EPA. To enable comparison, the CCS national A/C CO2 emissions were split into car/truck components and the ventilated seat credit was scaled up. The split CO2 emissions savings due to the CCS were 3.5 g/mi for a car and 4.4 g/mi for a truck. The CCS saved an additional 2.0 g/mi and 2.5 g/mi over the adjusted ventilated seat credit for a car and truck, respectively.« less

Isoprene emission and photosynthesis during heatwaves and drought in black locust

NASA Astrophysics Data System (ADS)

Bamberger, Ines; Ruehr, Nadine K.; Schmitt, Michael; Gast, Andreas; Wohlfahrt, Georg; Arneth, Almut

2017-08-01

Extreme weather conditions like heatwaves and drought can substantially affect tree physiology and the emissions of isoprene. To date, however, there is only limited understanding of isoprene emission patterns during prolonged heat stress and next to no data on emission patterns during coupled heat-drought stress or during post-stress recovery. We studied gas exchange and isoprene emissions of black locust trees under episodic heat stress and in combination with drought. Heatwaves were simulated in a controlled greenhouse facility by exposing trees to outside temperatures +10 °C, and trees in the heat-drought treatment were supplied with half of the irrigation water given to heat and control trees. Leaf gas exchange of isoprene, CO2 and H2O was quantified using self-constructed, automatically operating chambers, which were permanently installed on leaves (n = 3 per treatment). Heat and combined heat-drought stress resulted in a sharp decline of net photosynthesis (Anet) and stomatal conductance. Simultaneously, isoprene emissions increased 6- to 8-fold in the heat and heat-drought treatment, which resulted in a carbon loss that was equivalent to 12 and 20 % of assimilated carbon at the time of measurement. Once temperature stress was released at the end of two 15-day-long heatwaves, stomatal conductance remained reduced, while isoprene emissions and Anet recovered quickly to values of the control trees. Further, we found that isoprene emissions covaried with Anet during nonstress conditions, while during the heatwaves, isoprene emissions were not related to Anet but to light and temperature. Under standard air temperature and light conditions (here 30 °C and photosynthetically active radiation of 500 µmol m-2 s-1), isoprene emissions of the heat trees were by 45 % and the heat-drought trees were by 27 % lower than in control trees. Moreover, temperature response curves showed that not only the isoprene emission factor changed during both heat and heat-drought stress, but also the shape of the response. Because introducing a simple treatment-specific correction factor could not reproduce stress-induced isoprene emissions, different parameterizations of light and temperature functions are needed to describe tree isoprene emissions under heat and combined heat-drought stress. In order to increase the accuracy of predictions of isoprene emissions in response to climate extremes, such individual stress parameterizations should be introduced to current BVOC models.

Laser Absorption Measurements of Equivalence Ratios Studied Along With Their Coupling to Pressure Fluctuations in Lean Premixed Prevaporized (LPP) Combustion

NASA Technical Reports Server (NTRS)

Nguyen, Quang-Viet

2001-01-01

Concerns about damaging the Earth's ozone layer as a result of high levels of nitrogen oxides (known collectively as NOx) from high-altitude, high-speed aircraft have prompted the study of lean premixed prevaporized (LPP) combustion in aircraft engines. LPP combustion reduces NOx emissions principally by reducing the peak flame temperatures inside an engine. Recent advances in LPP technologies have realized exceptional reductions in pollutant emissions (single-digit ppm NOx for example). However, LPP combustion also presents major challenges: combustion instability and dynamic coupling effects between fluctuations in heat-release rate, dynamic pressure, and fuel pressure. These challenges are formidable and can literally shake an engine apart if uncontrolled. To better understand this phenomenon so that it can be controlled, we obtained real-time laser absorption measurements of the fuel vapor concentration (and equivalence ratio) simultaneously with the dynamic pressure, flame luminosity, and time-averaged gaseous emissions measurements in a research-type jet-A-fueled LPP combustor. The measurements were obtained in NASA Glenn Research Center's CE-5B optically accessible flame tube facility. The CE-5B facility provides inlet air temperatures and pressures similar to the actual operating conditions of real aircraft engines. The laser absorption measurements were performed using an infrared 3.39 micron HeNe laser in conjunction with a visible HeNe laser for liquid droplet scattering compensation.

Emissions, energy return and economics from utilizing forest residues for thermal energy compared to onsite pile burning

Treesearch

Greg Jones; Dan Loeffler; Edward Butler; Woodam Chung; Susan Hummel

2010-01-01

The emissions from delivering and burning forest treatment residue biomass in a boiler for thermal energy were compared with onsite disposal by pile-burning and using fossil fuels for the equivalent energy. Using biomass for thermal energy reduced carbon dioxide emissions on average by 39 percent and particulate matter emissions by 89 percent for boilers with emission...

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.

Chemiluminescence-based multivariate sensing of local equivalence ratios in premixed atmospheric methane-air flames

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

Tripathi, Markandey M.; Krishnan, Sundar R.; Srinivasan, Kalyan K.

Chemiluminescence emissions from OH*, CH*, C2, and CO2 formed within the reaction zone of premixed flames depend upon the fuel-air equivalence ratio in the burning mixture. In the present paper, a new partial least square regression (PLS-R) based multivariate sensing methodology is investigated and compared with an OH*/CH* intensity ratio-based calibration model for sensing equivalence ratio in atmospheric methane-air premixed flames. Five replications of spectral data at nine different equivalence ratios ranging from 0.73 to 1.48 were used in the calibration of both models. During model development, the PLS-R model was initially validated with the calibration data set using themore » leave-one-out cross validation technique. Since the PLS-R model used the entire raw spectral intensities, it did not need the nonlinear background subtraction of CO2 emission that is required for typical OH*/CH* intensity ratio calibrations. An unbiased spectral data set (not used in the PLS-R model development), for 28 different equivalence ratio conditions ranging from 0.71 to 1.67, was used to predict equivalence ratios using the PLS-R and the intensity ratio calibration models. It was found that the equivalence ratios predicted with the PLS-R based multivariate calibration model matched the experimentally measured equivalence ratios within 7%; whereas, the OH*/CH* intensity ratio calibration grossly underpredicted equivalence ratios in comparison to measured equivalence ratios, especially under rich conditions ( > 1.2). The practical implications of the chemiluminescence-based multivariate equivalence ratio sensing methodology are also discussed.« less

Simulated Fuel Economy and Emissions Performance during City and Interstate Driving for a Heavy-Duty Hybrid Truck

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

Daw, C. Stuart; Gao, Zhiming; Smith, David E.

2013-04-08

We compare simulated fuel economy and emissions for both conventional and hybrid class 8 heavy-duty diesel trucks operating over multiple urban and highway driving cycles. Both light and heavy freight loads were considered, and all simulations included full aftertreatment for NOx and particulate emissions controls. The aftertreatment components included a diesel oxidation catalyst (DOC), urea-selective catalytic NOx reduction (SCR), and a catalyzed diesel particulate filter (DPF). Our simulated hybrid powertrain was configured with a pre-transmission parallel drive, with a single electric motor between the clutch and gearbox. A conventional HD truck with equivalent diesel engine and aftertreatment was also simulatedmore » for comparison. Our results indicate that hybridization can significantly increase HD fuel economy and improve emissions control in city driving. However, there is less potential hybridization benefit for HD highway driving. A major factor behind the reduced hybridization benefit for highway driving is that there are fewer opportunities to utilize regenerative breaking. Our aftertreatment simulations indicate that opportunities for passive DPF regeneration are much greater for both hybrid and conventional trucks during highway driving due to higher sustained exhaust temperatures. When passive DPF regeneration is extensively utilized, the fuel penalty for particulate control is virtually eliminated, except for the 0.4%-0.9% fuel penalty associated with the slightly higher exhaust backpressure.« less

Subpart I: National Emission Standards for Radionuclide Emissions From Federal Facilities Other Than Nuclear Regulatory Commission Licensees and Not Covered by Subpart H

EPA Pesticide Factsheets

Subpart I limits radionuclide emissions to the ambient air from federal facilities that are not regulated elsewhere. The annual effective dose equivalent (ede) to any individual must not exceed 10 millirem (mrem).

Effect of aeration interval on oxygen consumption and GHG emission during pig manure composting.

PubMed

Zeng, Jianfei; Yin, Hongjie; Shen, Xiuli; Liu, Ning; Ge, Jinyi; Han, Lujia; Huang, Guangqun

2018-02-01

To verify the optimal aeration interval for oxygen supply and consumption and investigate the effect of aeration interval on GHG emission, reactor-scale composting was conducted with different aeration intervals (0, 10, 30 and 50 min). Although O 2 was sufficiently supplied during aeration period, it could be consumed to <10 vol% only when the aeration interval was 50 min, indicating that an aeration interval more than 50 min would be inadvisable. Compared to continuous aeration, reductions of the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent by 22.26-61.36%, 8.24-49.80% and 12.36-53.20%, respectively, was achieved through intermittent aeration. Specifically, both the total CH 4 and N 2 O emissions as well as the total GHG emission equivalent were inversely proportional to the duration of aeration interval (R 2  > 0.902), suggesting that lengthening the duration of aeration interval to some extent could effectively reduce GHG emission. Copyright © 2017 Elsevier Ltd. All rights reserved.

The broad-band X-ray spectral variability of Mrk 841

NASA Technical Reports Server (NTRS)

George, I. M.; Nandra, K.; Fabian, A. C.; Turner, T. J.; Done, C.; Day, C. S. R.

1993-01-01

A detailed spectral analysis of five X-ray observations of Mrk 841 with the EXOSAT, Ginga, and ROSAT satellites is reported. Variability is apparent in both the soft (0.1-1.0 keV) and medium (1-20 keV) energy bands. Above, 1 keV, the spectra are adequately modeled by a power law with a strong emission line of equivalent width 450 eV. The large equivalent width of the emission line indicates a strongly enhanced reflection component of the source compared with other Seyferts observed with Ginga. The implications of the results of the analysis for physical models of the emission regions in this and other X-ray bright Seyferts are briefly examined.

Objective Characterization of Snow Microstructure for Microwave Emission Modeling

NASA Technical Reports Server (NTRS)

Durand, Michael; Kim, Edward J.; Molotch, Noah P.; Margulis, Steven A.; Courville, Zoe; Malzler, Christian

2012-01-01

Passive microwave (PM) measurements are sensitive to the presence and quantity of snow, a fact that has long been used to monitor snowcover from space. In order to estimate total snow water equivalent (SWE) within PM footprints (on the order of approx 100 sq km), it is prerequisite to understand snow microwave emission at the point scale and how microwave radiation integrates spatially; the former is the topic of this paper. Snow microstructure is one of the fundamental controls on the propagation of microwave radiation through snow. Our goal in this study is to evaluate the prospects for driving the Microwave Emission Model of Layered Snowpacks with objective measurements of snow specific surface area to reproduce measured brightness temperatures when forced with objective measurements of snow specific surface area (S). This eliminates the need to treat the grain size as a free-fit parameter.

Accounting for climate and air quality damages in future U.S. electricity generation scenarios.

PubMed

Brown, Kristen E; Henze, Daven K; Milford, Jana B

2013-04-02

The EPA-MARKAL model of the U.S. electricity sector is used to examine how imposing emissions fees based on estimated health and environmental damages might change electricity generation. Fees are imposed on life-cycle emissions of SO(2), nitrogen oxides (NO(x)), particulate matter, and greenhouse gases (GHG) from 2015 through 2055. Changes in electricity production, fuel type, emissions controls, and emissions produced under various fees are examined. A shift in fuels used for electricity production results from $30/ton CO(2)-equivalent GHG fees or from criteria pollutant fees set at the higher-end of the range of published damage estimates, but not from criteria pollutant fees based on low or midrange damage estimates. With midrange criteria pollutant fees assessed, SO(2) and NOx emissions are lower than the business as usual case (by 52% and 10%, respectively), with larger differences in the western U.S. than in the eastern U.S. GHG emissions are not significantly impacted by midrange criteria pollutant fees alone; conversely, with only GHG fees, NO(x) emissions are reduced by up to 11%, yet SO(2) emissions are slightly higher than in the business as usual case. Therefore, fees on both GHG and criteria pollutants may be needed to achieve significant reductions in both sets of pollutants.

[Emission inventory of greenhouse gases from agricultural residues combustion: a case study of Jiangsu Province].

PubMed

Liu, Li-hua; Jiang, Jing-yan; Zong, Liang-gang

2011-05-01

Burning of agricultural crop residues was a major source greenhouse gases. In this study, the proportion of crop straws (rice, wheat, maize, oil rape, cotton and soja) in Jiangsu used as household fuel and direct open burning in different periods (1990-1995, 1996-2000, 2001-2005 and 2006-2008) was estimated through questionnaire. The emission factors of CO2, CO, CH4 and NO20 from the above six types of crop straws were calculated by the simulated burning experiment. Thus the emission inventory of greenhouse gases from crop straws burning was established according to above the burning percentages and emission factors, ratios of dry residues to production and crop productions of different periods in Jiangsu province. Results indicated that emission factors of CO2, CO, CH4 and N2O depended on crop straw type. The emission factors of CO2 and CH4 were higher for oil rape straw than the other straws, while the maize and the rice straw had the higher N2O and CO emission factor. Emission inventory of greenhouse gases from agricultural residues burning in Jiangsu province showed, the annual average global warming potential (GWP) of six tested crop straws were estimated to be 9.18 (rice straw), 4.35 (wheat straw), 2.55 (maize straw), 1.63 (oil rape straw), 0.55 (cotton straw) and 0. 39 (soja straw) Tg CO2 equivalent, respectively. Among the four study periods, the annual average GWP had no obvious difference between the 1990-1995 and 2006-2008 periods, while the maximal annual average GWP (23.83 Tg CO2 equivalent) happened in the 1996-2000 period, and the minimum (20.30 Tg CO2 equivalent) in 1996-2000 period.

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.

Current and Future Greenhouse Gas Emissions from Global Crop Intensification and Expansion

NASA Astrophysics Data System (ADS)

Carlson, K. M.; Gerber, J. S.; Mueller, N. D.; O'Connell, C.; West, P. C.

2014-12-01

Food systems currently contribute up to one-third of total anthropogenic greenhouse gas emissions, and these emissions are expected to rise as demand for agricultural products increases. Thus, improving the greenhouse gas emissions efficiency of agriculture - the tons or kilocalories of production per ton of CO2 equivalent emissions - will be critical to support a resilient future global system. Here, we model and evaluate global, 2000-era, spatially explicit relationships between a suite of greenhouse gas emissions from various agronomic practices (i.e., fertilizer application, peatland draining, and rice cultivation) and crop yields. Then, we predict potential emissions from future crop production increases achieved through intensification and extensification, including CO2 emissions from croplands replacing non-urban land cover. We find that 2000-era yield-scaled agronomic emissions are highly heterogeneous across crops types, crop management practices, and regions. Rice agriculture produces more total CO2-equivalent emissions than any other crop. Moreover, inundated rice in just a few countries contributes the vast majority of these rice emissions. Crops such as sunflower and cotton have low efficiency on a caloric basis. Our results suggest that intensification tends to be a more efficient pathway to boost greenhouse gas emissions efficiency than expansion. We conclude by discussing potential crop- and region-specific agricultural development pathways that may boost the greenhouse gas emissions efficiency of agriculture.

Hydrofluorocarbon (HFC) Emissions in China: An Inventory for 2005-2013 and Projections to 2050.

PubMed

Fang, Xuekun; Velders, Guus J M; Ravishankara, A R; Molina, Mario J; Hu, Jianxin; Prinn, Ronald G

2016-02-16

Many hydrofluorocarbons (HFCs) that are widely used as substitutes for ozone-depleting substances (now regulated under the Montreal Protocol) are very potent greenhouse gases (GHGs). China's past and future HFC emissions are of great interest because China has emerged as a major producer and consumer of HFCs. Here, we present for the first time a comprehensive inventory estimate of China's HFC emissions during 2005-2013. Results show a rapid increase in HFC production, consumption, and emissions in China during the period and that the emissions of HFC with a relatively high global warming potential (GWP) grew faster than those with a relatively low GWP. The proportions of China's historical HFC CO2-equivalent emissions to China's CO2 emissions or global HFC CO2-equivalent emissions increased rapidly during 2005-2013. Using the "business-as-usual" (BAU) scenario, in which HFCs are used to replace a significant fraction of hydrochlorofluorocarbons (HCFCs) in China (to date, there are no regulations on HFC uses in China), emissions of HFCs are projected to be significant components of China's and global future GHG emissions. However, potentials do exist for minimizing China's HFC emissions (for example, if regulations on HFC uses are established in China). Our findings on China's historical and projected HFC emission trajectories could also apply to other developing countries, with important implications for mitigating global GHG emissions.

40 CFR 61.102 - Standard.

Code of Federal Regulations, 2011 CFR

2011-07-01

....102 Standard. (a) Emissions of radionuclides, including iodine, to the ambient air from a facility... receive in any year an effective dose equivalent of 10 mrem/yr. (b) Emissions of iodine to the ambient air...

40 CFR 61.102 - Standard.

Code of Federal Regulations, 2010 CFR

2010-07-01

....102 Standard. (a) Emissions of radionuclides, including iodine, to the ambient air from a facility... receive in any year an effective dose equivalent of 10 mrem/yr. (b) Emissions of iodine to the ambient air...

Using backup generators for meeting peak electricity demand: a sensitivity analysis on emission controls, location, and health endpoints.

PubMed

Gilmore, Elisabeth A; Adams, Peter J; Lave, Lester B

2010-05-01

Generators installed for backup power during blackouts could help satisfy peak electricity demand; however, many are diesel generators with nonnegligible air emissions that may damage air quality and human health. The full (private and social) cost of using diesel generators with and without emission control retrofits for fine particulate matter (PM2.5) and nitrogen oxides (NOx) were compared with a new natural gas turbine peaking plant. Lower private costs were found for the backup generators because the capital costs are mostly ascribed to reliability. To estimate the social costs from air quality, the changes in ambient concentrations of ozone (O3) and PM2.5 were modeled using the Particulate Matter Comprehensive Air Quality Model with extensions (PMCAMx) chemical transport model. These air quality changes were translated to their equivalent human health effects using concentration-response functions and then into dollars using estimates of "willingness-to-pay" to avoid ill health. As a case study, 1000 MW of backup generation operating for 12 hr/day for 6 days in each of four eastern U.S. cities (Atlanta, Chicago, Dallas, and New York) was modeled. In all cities, modeled PM2.5 concentrations increased (up to 5 microg/m3) due mainly to primary emissions. Smaller increases and decreases were observed for secondary PM2.5 with more variation between cities. Increases in NOx, emissions resulted in significant nitrate formation (up to 1 microg/m3) in Atlanta and Chicago. The NOx emissions also caused O3 decreases in the urban centers and increases in the surrounding areas. For PM2.5, a social cost of approximately $2/kWh was calculated for uncontrolled diesel generators in highly populated cities but was under 10 cent/kWh with PM2.5 and NOx controls. On a full cost basis, it was found that properly controlled diesel generators are cost-effective for meeting peak electricity demand. The authors recommend NOx and PM2.5 controls.

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.

The impact of municipal solid waste management on greenhouse gas emissions in the United States.

PubMed

Weitz, Keith A; Thorneloe, Susan A; Nishtala, Subba R; Yarkosky, Sherry; Zannes, Maria

2002-09-01

Technological advancements, environmental regulations, and emphasis on resource conservation and recovery have greatly reduced the environmental impacts of municipal solid waste (MSW) management, including emissions of greenhouse gases (GHGs). This study was conducted using a life-cycle methodology to track changes in GHG emissions during the past 25 years from the management of MSW in the United States. For the baseline year of 1974, MSW management consisted of limited recycling, combustion without energy recovery, and landfilling without gas collection or control. This was compared with data for 1980, 1990, and 1997, accounting for changes in MSW quantity, composition, management practices, and technology. Over time, the United States has moved toward increased recycling, composting, combustion (with energy recovery) and landfilling with gas recovery, control, and utilization. These changes were accounted for with historical data on MSW composition, quantities, management practices, and technological changes. Included in the analysis were the benefits of materials recycling and energy recovery to the extent that these displace virgin raw materials and fossil fuel electricity production, respectively. Carbon sinks associated with MSW management also were addressed. The results indicate that the MSW management actions taken by U.S. communities have significantly reduced potential GHG emissions despite an almost 2-fold increase in waste generation. GHG emissions from MSW management were estimated to be 36 million metric tons carbon equivalents (MMTCE) in 1974 and 8 MMTCE in 1997. If MSW were being managed today as it was in 1974, GHG emissions would be approximately 60 MMTCE.

Cyclo-octafluorobutane (PFC-318) in the global atmosphere

NASA Astrophysics Data System (ADS)

Muhle, J.; Vollmer, M. K.; Fraser, P. J.; Rhee, T. S.; Ivy, D. J.; Arnold, T.; Harth, C. M.; Salameh, P.; O'Doherty, S.; Young, D.; Steele, P.; Krummel, P. B.; Leist, M.; Schmidbauer, N.; Lunder, C.; Kim, J.; Kim, K.; Reimann, S.; Simmonds, P.; Prinn, R. G.; Weiss, R. F.

2010-12-01

PFC-318 (c-C4F8, cyclo-octafluorobutane) is a long-lived (3200 years) perfluorocarbon (PFC) greenhouse gas with a high 100-year Global Warming Potential (GWP100 = 10,300) and a wide range of industrial uses. We extend previous atmospheric measurements of PFC-318 in the Cape Grim Air Archive (Oram, 1999) with our new in situ measurements from remote and urban AGAGE (Advanced Global Atmospheric Gases Experiment) and affiliated stations. Our longest in situ record is from the Jungfraujoch observatory in the Swiss Alps, and our data set is augmented by measurements of flasks from the King Sejong and Troll coastal Antarctic stations and several locations in the Northern Hemisphere. In mid-2009 we find ˜1.25 ppt (parts-per-trillion, dry mol fraction) in the Northern Hemisphere and ˜1.20 ppt in the Southern Hemisphere, with rise rates of ˜0.03 ppt/yr and an interhemispheric ratio of ˜1.04. We obtain PFC-318 emissions for 2008-2010 of ˜1 Gg/yr using a simple box model, and preliminary measurements of older archived air at SIO indicate similar emissions since at the least the late 1990s. In contrast, the EDGAR v4 emissions database estimates much lower PFC-318 emissions of 0.02 Gg/yr for 2005. Using GWP100 we calculate ˜10 million tons of CO2-equivalent PFC-318 emissions/yr for 2008-2010, about double the CO2-equivalent PFC-218 annual emissions, or 0.4 times the CO2-equivalent PFC-116 annual emissions, reported for 2008-2009 by Mühle et al. (2010). Thus PFC-318 is the third most important PFC in terms of CO2-equivalent emissions. We find mostly baseline conditions at remote AGAGE stations and urban sites in the USA, Europe, and Australia, in contrast to frequent above baseline conditions at Gosan station, Jeju Island, South Korea, indicating significant emission sources in East Asia as found by Saito et al. (2010). Oram, D.E., Trends of long-lived anthropogenic halocarbons in the Southern Hemisphere and model calculation of global emissions, Ph.D. thesis, University of East Anglia, Norwich, U.K., 1999. Mühle et al., Perfluorocarbons in the global atmosphere: tetrafluoromethane, hexafluoroethane, and octafluoropropane, Atmos. Chem. Phys., 10(11), 5145-5164, doi:10.5194/acp-10-5145-2010, 2010. Saito et al., Large Emissions of Perfluorocarbons in East Asia Deduced from Continuous Atmospheric Measurements, Environ. Sci. Technol., 44(11), 4089-4095, doi:10.1021/es1001488, 2010.

Control of fossil-fuel particulate black carbon and organic matter, possibly the most effective method of slowing global warming

NASA Astrophysics Data System (ADS)

Jacobson, Mark Z.

2002-10-01

Under the 1997 Kyoto Protocol, no control of black carbon (BC) was considered. Here, it is found, through simulations in which 12 identifiable effects of aerosol particles on climate are treated, that any emission reduction of fossil-fuel (f.f.) particulate BC plus associated organic matter (OM) may slow global warming more than may any emission reduction of CO2 or CH4 for a specific period. When all f.f. BC + OM and anthropogenic CO2 and CH4 emissions are eliminated together, the period is 25-100 years. It is also estimated that historical net global warming can be attributed roughly to greenhouse gas plus f.f. BC + OM warming minus substantial cooling by other particles. Eliminating all f.f. BC + OM could eliminate 20-45% of net warming (8-18% of total warming before cooling is subtracted out) within 3-5 years if no other change occurred. Reducing CO2 emissions by a third would have the same effect, but after 50-200 years. Finally, diesel cars emitting continuously under the most recent U.S. and E.U. particulate standards (0.08 g/mi; 0.05 g/km) may warm climate per distance driven over the next 100+ years more than equivalent gasoline cars. Thus, fuel and carbon tax laws that favor diesel appear to promote global warming. Toughening vehicle particulate emission standards by a factor of 8 (0.01 g/mi; 0.006 g/km) does not change this conclusion, although it shortens the period over which diesel cars warm to 13-54 years. Although control of BC + OM can slow warming, control of greenhouse gases is necessary to stop warming. Reducing BC + OM will not only slow global warming but also improve human health.

Controls on methane concentrations and fluxes in streams draining human-dominated landscapes

USGS Publications Warehouse

Crawford, John T.; Stanley, Emily H.

2016-01-01

Streams and rivers are active processors of carbon, leading to significant emissions of CO2 and possibly CH4 to the atmosphere. Patterns and controls of CH4 in fluvial ecosystems remain relatively poorly understood. Furthermore, little is known regarding how major human impacts to fluvial ecosystems may be transforming their role as CH4 producers and emitters. Here, we examine the consequences of two distinct ecosystem changes as a result of human land use: increased nutrient loading (primarily as nitrate), and increased sediment loading and deposition of fine particles in the benthic zone. We did not find support for the hypothesis that enhanced nitrate loading down-regulates methane production via thermodynamic or toxic effects. We did find strong evidence that increased sedimentation and enhanced organic matter content of the benthos lead to greater methane production (diffusive + ebullitive flux) relative to pristine fluvial systems in northern Wisconsin (upper Midwest, USA). Overall, streams in a human-dominated landscape of southern Wisconsin were major regional sources of CH4 to the atmosphere, equivalent to ~20% of dairy cattle emissions, or ~50% of a landfill’s annual emissions. We suggest that restoration of the benthic environment (reduced fine deposits) could lead to reduced CH4 emissions, while decreasing nutrient loading is likely to have limited impacts to this ecosystem process.

40 CFR Appendix A-3 to Part 60 - Test Methods 4 through 5I

Code of Federal Regulations, 2011 CFR

2011-07-01

... isokinetic sampling rates prior to a pollutant emission measurement run. The approximation method described... with a pollutant emission measurement run. When it is, calculation of percent isokinetic, pollutant emission rate, etc., for the run shall be based upon the results of the reference method or its equivalent...

Air quality impacts from prescribed forest fires under different management practices.

PubMed

Tian, Di; Wang, Yuhang; Bergin, Michelle; Hu, Yongtao; Liu, Yongqiang; Russell, Armistead G

2008-04-15

Large amounts of air pollutants are emitted during prescribed forest fires. Such emissions and corresponding air quality impacts can be modulated by different forest management practices. The impacts of changing burning seasons and frequencies and of controlling emissions during smoldering on regional air quality in Georgia are quantified using source-oriented air quality modeling, with modified emissions from prescribed fires reflecting effects of each practice. Equivalent fires in the spring and winter are found to have a greater impact on PM2.5 than those in summer, though ozone impacts are larger from spring and summer fires. If prescribed fires are less frequent more biofuel is burnt in each fire, leading to larger emissions and air quality impacts per fire. For example, emissions from a fire with a 5-year fire return interval (FRI) are 72% larger than those from a fire of the same acreage with a 2-year FRI. However, corresponding long-term regional impacts are reduced with the longer FRI since the annual burned area is reduced. Total emissions for fires in Georgia with a 5-year FRI are 32% less than those with a 2-year FRI. Smoldering emissions can lead to approximately 1.0 or 1.9 microg/m3 of PM2.5 in the Atlanta PM2.5 nonattainment area during March 2002.

Lean mixture engine testing and evaluation program. [for automobile engine pollution and fuel performances

NASA Technical Reports Server (NTRS)

Dowdy, M. W.; Hoehn, F. W.; Griffin, D. C.

1975-01-01

Experimental results for fuel consumption and emissions are presented for a 350 CID (5.7 liter) Chevrolet V-8 engine modified for lean operation with gasoline. The lean burn engine achieved peak thermal efficiency at an equivalence ratio of 0.75 and a spark advance of 60 deg BTDC. At this condition the lean burn engine demonstrated a 10% reduction in brake specific fuel consumption compared with the stock engine; however, NOx and hydrocarbon emissions were higher. With the use of spark retard and/or slightly lower equivalence ratios, the NOx emissions performance of the stock engine was matched while showing a 6% reduction in brake specific fuel consumption. Hydrocarbon emissions exceeded the stock values in all cases. Diagnostic data indicate that lean performance in the engine configuration tested is limited by ignition delay, cycle-to-cycle pressure variations, and cylinder-to-cylinder distribution.

EMI survey for maritime satellite, L-band, shipboard terminal

NASA Technical Reports Server (NTRS)

Taylor, R. E.; Brandel, D. L.; Hill, J. S.

1975-01-01

The paper presents results of an onboard EMI survey of an L-band shipboard terminal for operation with two geostationary maritime satellites. Significant EMC results include: (1) antenna noise temperature measurements indicate a maximum of 70 K steady background component at 1.6 GHz at sea for elevation angles of 5 degrees and higher; (2) field intensity measurements from 1-10 GHz show that a L-band terminal can operate simultaneously with onboard S-band and X-band navigation radar; (3) radar transmitter case emissions, below deck, in-band from 1535-1660 MHz, at 1 m distance from the cabinet, are equivalent, or greater than above-deck emissions in the same frequency range; and (4) conducted-emission tests of a ship's power lines to both radars show both narrow band and broad band emissions are 15 dB to 50 dB higher than equivalent U.S. commercial power lines from 150 kHz to 32 MHz.

Greenhouse gas emissions of different waste treatment options for sector-specific commercial and industrial waste in Germany.

PubMed

Helftewes, Markus; Flamme, Sabine; Nelles, Michael

2012-04-01

This article investigates greenhouse gas (GHG) emissions from commercial and industrial (C&I) waste treatment considering five sector-specific waste compositions and four different treatment scenarios in Germany. Results show that the highest share of CO₂-equivalent emissions can be avoided in each of the analysed industrial sectors if solid recovered fuel (SRF) is produced for co-incineration in cement kilns. Across all industries, emissions of approximately 680 kg CO₂-eq. Mg⁻¹ C&I waste can be avoided on average under this scenario. The combustion of C&I waste in waste incineration plants without any previous mechanical treatment generates the lowest potential to avoid GHG emissions with a value of approximately 50 kg CO₂-eq. Mg⁻¹ C&I waste on average in all industries. If recyclables are sorted, this can save emissions of approximately 280 kg CO₂-eq. Mg⁻¹ C&I waste while the treatment in SRF power plants amounts to savings of approximately 210 kg CO₂-eq. Mg⁻¹ C&I waste. A comparison of the treatment scenarios of the waste from these five sectors shows that waste treatment of the craft sector leads to the lowest CO₂-equivalent reduction rates of all scenarios. In contrast, the treatment of waste from catering sector leads to the highest CO₂-equivalent reduction rates except for direct incineration in waste incineration plants. The sensitivity analysis of the different scenarios for this paper shows that the efficiency and the substitution factor of energy have a relevant influence on the result. Changes in the substitution factor of 10% can result in changes in emissions of approximately 55 to 75 kg CO₂-eq. Mg⁻¹ in waste incineration plants and approximately 90 kg CO₂-eq. Mg⁻¹ in the case of cement kilns.

A positron emission tomography study of nigro-striatal dopaminergic mechanisms underlying attention: implications for ADHD and its treatment

PubMed Central

Fryer, Tim D.; Hong, Young T.; Smith, Rob; Brichard, Laurent; Acosta-Cabronero, Julio; Chamberlain, Samuel R.; Tait, Roger; Izquierdo, David; Regenthal, Ralf; Dowson, Jonathan; Suckling, John; Baron, Jean-Claude; Aigbirhio, Franklin I.; Robbins, Trevor W.; Sahakian, Barbara J.; Müller, Ulrich

2013-01-01

Through the combined use of 18F-fallypride positron emission tomography and magnetic resonance imaging this study examined the neural mechanisms underlying the attentional deficits associated with attention deficit/hyperactivity disorder and their potential reversal with a single therapeutic dose of methylphenidate. Sixteen adult patients with attention deficit/hyperactivity disorder and 16 matched healthy control subjects were positron emission tomography and magnetic resonance imaging scanned and tested on a computerized sustained attention task after oral methylphenidate (0.5 mg/kg) and placebo administration in a within-subject, double-blind, cross-over design. Although patients with attention deficit/hyperactivity disorder as a group showed significant attentional deficits and reduced grey matter volume in fronto-striato-cerebellar and limbic networks, they had equivalent D2/D3 receptor availability and equivalent increases in endogenous dopamine after methylphenidate treatment to that observed in healthy control subjects. However, poor attentional performers drawn from both the attention deficit/hyperactivity disorder and the control groups had significantly reduced left caudate dopamine activity. Methylphenidate significantly increased dopamine levels in all nigro-striatal regions, thereby normalizing dopamine levels in the left caudate in low performers. Behaviourally, methylphenidate improved sustained attention in a baseline performance-dependent manner, irrespective of diagnosis. This finding was accompanied by an equally performance-dependent effect of the drug on dopamine release in the midbrain, whereby low performers showed reduced dopamine release in this region. Collectively, these findings support a dimensional model of attentional deficits and underlying nigro-striatal dopaminergic mechanisms of attention deficit/hyperactivity disorder that extends into the healthy population. Moreover, they confer midbrain dopamine autoreceptors a hitherto neglected role in the therapeutic effects of oral methylphenidate in attention deficit/hyperactivity disorder. The absence of significant case–control differences in D2/D3 receptor availability (despite the observed relationships between dopamine activity and attention) suggests that dopamine dysregulation per se is unlikely to be the primary cause underlying attention deficit/hyperactivity disorder pathology in adults. This conclusion is reinforced by evidence of neuroanatomical changes in the same set of patients with attention deficit/hyperactivity disorder. PMID:24163364

Bayesian Redshift Classification of Emission-line Galaxies with Photometric Equivalent Widths

NASA Astrophysics Data System (ADS)

Leung, Andrew S.; Acquaviva, Viviana; Gawiser, Eric; Ciardullo, Robin; Komatsu, Eiichiro; Malz, A. I.; Zeimann, Gregory R.; Bridge, Joanna S.; Drory, Niv; Feldmeier, John J.; Finkelstein, Steven L.; Gebhardt, Karl; Gronwall, Caryl; Hagen, Alex; Hill, Gary J.; Schneider, Donald P.

2017-07-01

We present a Bayesian approach to the redshift classification of emission-line galaxies when only a single emission line is detected spectroscopically. We consider the case of surveys for high-redshift Lyα-emitting galaxies (LAEs), which have traditionally been classified via an inferred rest-frame equivalent width (EW {W}{Lyα }) greater than 20 Å. Our Bayesian method relies on known prior probabilities in measured emission-line luminosity functions and EW distributions for the galaxy populations, and returns the probability that an object in question is an LAE given the characteristics observed. This approach will be directly relevant for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), which seeks to classify ˜106 emission-line galaxies into LAEs and low-redshift [{{O}} {{II}}] emitters. For a simulated HETDEX catalog with realistic measurement noise, our Bayesian method recovers 86% of LAEs missed by the traditional {W}{Lyα } > 20 Å cutoff over 2 < z < 3, outperforming the EW cut in both contamination and incompleteness. This is due to the method’s ability to trade off between the two types of binary classification error by adjusting the stringency of the probability requirement for classifying an observed object as an LAE. In our simulations of HETDEX, this method reduces the uncertainty in cosmological distance measurements by 14% with respect to the EW cut, equivalent to recovering 29% more cosmological information. Rather than using binary object labels, this method enables the use of classification probabilities in large-scale structure analyses. It can be applied to narrowband emission-line surveys as well as upcoming large spectroscopic surveys including Euclid and WFIRST.

Life-cycle assessment of electricity generation systems and applications for climate change policy analysis

NASA Astrophysics Data System (ADS)

Meier, Paul Joseph

This research uses Life-Cycle Assessment (LCA) to better understand the energy and environmental performance for two electricity generation systems, a 620 MW combined-cycle natural gas plant, and an 8kW building-integrated photovoltaic system. The results of the LCA are used to provide an effective and accurate means for evaluating greenhouse gas emission reduction strategies for U.S. electricity generation. The modern combined-cycle plant considered in this thesis is nominally 48% thermally efficient, but it is only 43% energy efficient when evaluated across its entire life-cycle, due primarily to energy losses during the natural gas fuel cycle. The emission rate for the combined-cycle natural gas plant life-cycle (469 tonnes CO2-equivalent per GWeh), was 23% higher than the emission rate from plant operation alone (382 tonnes CO2-equivalent per GWeh). Uncertainty in the rate of fuel-cycle methane releases results in a potential range of emission rates between 457 to 534 tonnes CO 2-equivalent per GWeh for the studied plant. The photovoltaic system modules have a sunlight to DC electricity conversion efficiency of 5.7%. However, the system's sunlight to AC electricity conversion efficiency is 4.3%, when accounting for life-cycle energy inputs, as well as losses due to system wiring, AC inversion, and module degradation. The LCA illustrates that the PV system has a low, but not zero, life-cycle greenhouse gas emission rate of 39 Tonnes CO2-equivalent per GWeh. A ternary method of evaluation is used to evaluate three greenhouse gas mitigation alternatives: (1) fuel-switching from coal to natural gas for Kyoto-based compliance, (2) fuel-switching from coal to nuclear/renewable for Kyoto based compliance, and (3) fuel-switching to meet the White House House's Global Climate Change Initiative. In a moderate growth scenario, fuel-switching from coal to natural gas fails to meet a Kyoto-based emission target, while fuel-switching to nuclear/renewable meets the emission objective by reducing coal generated electricity 32% below 2000 levels. The Global Climate Change Initiative allows annual greenhouse gas emissions to increase to levels that are 54% higher than the proposed U.S. commitment under the Kyoto Protocol.

A spatially resolved fuel-based inventory of Utah and Colorado oil and natural gas emissions

NASA Astrophysics Data System (ADS)

Gorchov Negron, A.; McDonald, B. C.; De Gouw, J. A.; Frost, G. J.

2015-12-01

A fuel-based approach is presented for estimating emissions from US oil and natural gas production that utilizes state-level fuel surveys of oil and gas engine activity, well-level production data, and emission factors for oil and gas equipment. Emissions of carbon dioxide (CO2) and nitrogen oxides (NOx) are mapped on a 4 km x 4 km horizontal grid for 2013-14 in Utah and Colorado. Emission sources include combustion from exploration (e.g., drilling), production (e.g., heaters, dehydrators, and compressor engines), and natural gas processing plants, which comprise a large fraction of the local combustion activity in oil and gas basins. Fuel-based emission factors of NOx are from the U.S. Environmental Protection Agency, and applied to spatially-resolved maps of CO2 emissions. Preliminary NOx emissions from this study are estimated for the Uintah Basin, Utah, to be ~5300 metric tons of NO2-equivalent in 2013. Our result compares well with an observations-based top-down emissions estimate of NOx derived from a previous study, ~4200 metric tons of NO2-equivalent. By contrast, the 2011 National Emissions Inventory estimates oil and gas emissions of NOx to be ~3 times higher than our study in the Uintah Basin. We intend to expand our fuel-based approach to map combustion-related emissions in other U.S. oil and natural gas basins and compare with additional observational datasets.

Bias of averages in life-cycle footprinting of infrastructure: truck and bus case studies.

PubMed

Taptich, Michael N; Horvath, Arpad

2014-11-18

The life-cycle output (e.g., level of service) of infrastructure systems heavily influences their normalized environmental footprint. Many studies and tools calculate emission factors based on average productivity; however, the performance of these systems varies over time and space. We evaluate the appropriate use of emission factors based on average levels of service by comparing them to those reflecting a distribution of system outputs. For the provision of truck and bus services where fuel economy is assumed constant over levels of service, emission factor estimation biases, described by Jensen's inequality, always result in larger-than-expected environmental impacts (3%-400%) and depend strongly on the variability and skew of truck payloads and bus ridership. Well-to-wheel greenhouse gas emission factors for diesel trucks in California range from 87 to 1,500 g of CO2 equivalents per ton-km, depending on the size and type of trucks and the services performed. Along a bus route in San Francisco, well-to-wheel emission factors ranged between 53 and 940 g of CO2 equivalents per passenger-km. The use of biased emission factors can have profound effects on various policy decisions. If average emission rates must be used, reflecting a distribution of productivity can reduce emission factor biases.

40 CFR 63.5798 - What if I want to use, or I manufacture, an application technology (new or existing) whose...

Code of Federal Regulations, 2010 CFR

2010-07-01

...: Reinforced Plastic Composites Production Calculating Organic Hap Emissions Factors for Open Molding and... description of the resin or gel coat application technology and supporting organic HAP emissions test data obtained using EPA test methods or their equivalent. The emission test data should be obtained using a...

40 CFR 63.5798 - What if I want to use, or I manufacture, an application technology (new or existing) whose...

Code of Federal Regulations, 2011 CFR

2011-07-01

...: Reinforced Plastic Composites Production Calculating Organic Hap Emissions Factors for Open Molding and... description of the resin or gel coat application technology and supporting organic HAP emissions test data obtained using EPA test methods or their equivalent. The emission test data should be obtained using a...

40 CFR 63.5798 - What if I want to use, or I manufacture, an application technology (new or existing) whose...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Pollutants: Reinforced Plastic Composites Production Calculating Organic Hap Emissions Factors for Open... organic HAP emissions test data obtained using EPA test methods or their equivalent. The emission test data should be obtained using a range of resin or gel coat HAP contents to demonstrate the...

40 CFR 63.5798 - What if I want to use, or I manufacture, an application technology (new or existing) whose...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Pollutants: Reinforced Plastic Composites Production Calculating Organic Hap Emissions Factors for Open... organic HAP emissions test data obtained using EPA test methods or their equivalent. The emission test data should be obtained using a range of resin or gel coat HAP contents to demonstrate the...

40 CFR 63.5798 - What if I want to use, or I manufacture, an application technology (new or existing) whose...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Pollutants: Reinforced Plastic Composites Production Calculating Organic Hap Emissions Factors for Open... organic HAP emissions test data obtained using EPA test methods or their equivalent. The emission test data should be obtained using a range of resin or gel coat HAP contents to demonstrate the...

Evaluation of FIDC system. [fuel vapor injector/ogniter and lean limit controller for automobile engines

NASA Technical Reports Server (NTRS)

Hall, R. A.; Dowdy, M. W.; Price, T. W.

1978-01-01

A fuel vapor injector/igniter system was evaluated for its effect on automobile engine performance, fuel economy, and exhaust emissions. Improved fuel economy and emissions, found during the single cylinder tests were not realized with a multicylinder engine. Multicylinder engine tests were conducted to compare the system with both a stock and modified stock configuration. A comparison of cylinder-to-cylinder equivalence ratio distribution was also obtained from the multicylinder engine tests. The multicylinder engine was installed in a vehicle was tested on a chassis dynamometer to compare the system with stock and modified stock configurations. The fuel vapor injector/igniter system (FIDC) configuration demonstrated approximately five percent improved fuel economy over the stock configuration, but the modified stock configuration demonstrated approximately twelve percent improved fuel economy. The hydrocarbon emissions were approximately two-hundred-thirty percent higher with the FIDC system than with the stock configuration. Both the FIDC system and the modified stock configuration adversely affected driveability. The FIDC system demonstrated a modest fuel savings, but with the penalty of increased emissions, and loss of driveability.

Investigation of methyl decanoate combustion in an optical direct-injection diesel engine

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

Cheng, A. S.; Dumitrescu, Cosmin E.; Mueller, Charles J.

In this study, an optically accessible heavy-duty diesel engine was used to investigate the impact of methyl decanoate (MD) on combustion and emissions. A specific goal of the study was to determine if MD could enable soot-free leaner-lifted flame combustion (LLFC) – a mode of mixing-controlled combustion associated with fuel-air equivalence ratios below approximately two. An ultra-low sulfur diesel certification fuel (CF) was used as the baseline fuel, and experiments were conducted at two fuel-injection pressures with three levels of charge-gas dilution. In addition to conventional pressure-based and engine-out emissions measurements, exhaust laser-induced incandescence, in-cylinder natural luminosity (NL), and in-cylindermore » chemiluminescence (CL) diagnostics were used to provide detailed insight into combustion processes.« less

Investigation of methyl decanoate combustion in an optical direct-injection diesel engine

DOE PAGES

Cheng, A. S.; Dumitrescu, Cosmin E.; Mueller, Charles J.

2014-11-24

In this study, an optically accessible heavy-duty diesel engine was used to investigate the impact of methyl decanoate (MD) on combustion and emissions. A specific goal of the study was to determine if MD could enable soot-free leaner-lifted flame combustion (LLFC) – a mode of mixing-controlled combustion associated with fuel-air equivalence ratios below approximately two. An ultra-low sulfur diesel certification fuel (CF) was used as the baseline fuel, and experiments were conducted at two fuel-injection pressures with three levels of charge-gas dilution. In addition to conventional pressure-based and engine-out emissions measurements, exhaust laser-induced incandescence, in-cylinder natural luminosity (NL), and in-cylindermore » chemiluminescence (CL) diagnostics were used to provide detailed insight into combustion processes.« less

Is obesity associated with global warming?

PubMed

Squalli, J

2014-12-01

Obesity is a national epidemic that imposes direct medical and indirect economic costs on society. Recent scholarly inquiries contend that obesity also contributes to global warming. The paper investigates the relationship between greenhouse gas emissions and obesity. Cross-sectional state-level data for the year 2010. Multiple regression analysis using least squares with bootstrapped standard errors and quantile regression. States with higher rates of obesity are associated with higher CO2 and CH4 emissions (p < 0.05) and marginally associated with higher N2O emissions (p < 0.10), net of other factors. Reverting to the obesity rates of the year 2000 across the entire United States could decrease greenhouse gas emissions by about two percent, representing more than 136 million metric tons of CO2 equivalent. Future studies should establish clear causality between obesity and emissions by using longitudinal data while controlling for other relevant factors. They should also consider identifying means to net out the potential effects of carbon sinks, conversion of CH4 to energy, cross-state diversion, disposal, and transfer of municipal solid waste, and potentially lower energy consumption from increased sedentariness. Copyright © 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Comparing primary energy attributed to renewable energy with primary energy equivalent to determine carbon abatement in a national context.

PubMed

Gallachóir, Brian P O; O'Leary, Fergal; Bazilian, Morgan; Howley, Martin; McKeogh, Eamon J

2006-01-01

The current conventional approach to determining the primary energy associated with non-combustible renewable energy (RE) sources such as wind energy and hydro power is to equate the electricity generated from these sources with the primary energy supply. This paper compares this with an approach that was formerly used by the IEA, in which the primary energy equivalent attributed to renewable energy was equated with the fossil fuel energy it displaces. Difficulties with implementing this approach in a meaningful way for international comparisons lead to most international organisations abandoning the primary energy equivalent methodology. It has recently re-emerged in prominence however, as efforts grow to develop baseline procedures for quantifying the greenhouse gas (GHG) emissions avoided by renewable energy within the context of the Kyoto Protocol credit trading mechanisms. This paper discusses the primary energy equivalent approach and in particular the distinctions between displacing fossil fuel energy in existing plant or in new plant. The approach is then extended provide insight into future primary energy displacement by renewable energy and to quantify the amount of CO2 emissions avoided by renewable energy. The usefulness of this approach in quantifying the benefits of renewable energy is also discussed in an energy policy context, with regard to increasing security of energy supply as well as reducing energy-related GHG (and other) emissions. The approach is applied in a national context and Ireland is case study country selected for this research. The choice of Ireland is interesting in two respects. The first relates to the high proportion of electricity only fossil fuel plants in Ireland resulting in a significant variation between primary energy and primary energy equivalent. The second concerns Ireland's poor performance to date in limiting GHG emissions in line with its Kyoto target and points to the need for techniques to quantify the potential contribution of renewable energy in achieving the target set.

Relative impact of short-term emissions controls on gas and particle-phase oxidative potential during the 2015 China Victory Day Parade in Beijing, China

NASA Astrophysics Data System (ADS)

Huang, Wei; Fang, Dongqing; Shang, Jing; Li, Zhengqiang; Zhang, Yang; Huo, Peng; Liu, Zhaoying; Schauer, James J.; Zhang, Yuanxun

2018-06-01

A field observation focusing on reactive oxygen species (ROS) was conducted before, during, and after the 2015 China Victory Day Parade to understand the influence of short-term emissions controls on atmospheric oxidative activity. The hourly average concentrations of PM2.5, SO2, NO, NO2, CO, O3, as well as gas and particle-phase ROS, were measured using a series of online instruments. PM2.5 concentrations during control days were significantly lower than non-control days, which directly lead to the "Parade Blue", yet reductions of most gaseous pollutants except SO2 were not so obvious as PM. Similarly, the control measures also led to a great loss of particle-phase ROS throughout the control period, while the reduction of ROS in gas phase was not obvious until the more stringent measures implemented since September 1. Furthermore, only weak positive correlations were observed among ROS and some other measured species, indicating ROS concentrations were affected by a number of comprehensive factors that single marker could not capture. Meanwhile, meteorological condition and regional transportation were also shown to be the minor factors affecting atmospheric oxidizing capacity. The results of this observation mainly revealed the control measures were conducive to reducing particle-related ROS. However, the reduction of gas-phase ROS activity was less effective given the menu of controls employed for the 2015 China Victory Day Parade. Therefore, short-term emissions controls only aimed to PM reduction and visibility improvement will produce the blue sky but will not equivalently reduce the gas-phase ROS. Supplemental control measures will be needed to further reduce gas-phase ROS concentrations.

CAFE Standards (released in AEO2010)

EIA Publications

2010-01-01

Pursuant to the Presidents announcement of a National Fuel Efficiency Policy, the National Highway Traffic Safety Administration (NHTSA) and the EPA have promulgated nationally coordinated standards for tailpipe Carbon Dioxide (CO2)-equivalent emissions and fuel economy for light-duty vehicles (LDVs), which includes both passenger cars and light-duty trucks. In the joint rulemaking, the Environmental Protection Agency is enacting CO2-equivalent emissions standards under the Clean Air Act (CAA), and NHTSA is enacting companion Corporate Average Fuel Economy standards under the Energy Policy and Conservation Act, as amended by the Energy Independence and Security Act of 2007.

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.

The challenge to NOx emission control for heavy-duty diesel vehicles in China

NASA Astrophysics Data System (ADS)

Wu, Y.; Zhang, S. J.; Li, M. L.; Ge, Y. S.; Shu, J. W.; Zhou, Y.; Xu, Y. Y.; Hu, J. N.; Liu, H.; Fu, L. X.; He, K. B.; Hao, J. M.

2012-07-01

China's new "Twelfth Five-Year Plan" set a target for total NOx emission reduction of 10% for the period of 2011-2015. Heavy-duty diesel vehicles (HDDVs) have been considered a major contributor to NOx emissions in China. Beijing initiated a comprehensive vehicle test program in 2008. This program included a sub-task for measuring on-road emission profiles of hundreds of HDDVs using portable emission measurement systems (PEMS). The major finding is that neither the on-road distance-specific (g km -1) nor brake-specific (g kW h-1) NOx emission factors for diesel buses and heavy-duty diesel trucks improved in most cases as emission standards became more stringent. For example, the average NOx emission factors for Euro II, Euro III and Euro IV buses are 11.3±3.3 g km-1, 12.5± 1.3 g km-1, and 11.8±2.0 g km-1, respectively. No statistically significant difference in NOx emission factors was observed between Euro II and III buses. Even for Euro IV buses equipped with SCR systems, the NOx emission factors are similar to Euro III buses. The data regarding real-time engine performance of Euro IV buses suggest the engine certification cycles did not reflect their real-world operating conditions. These new on-road test results indicate that previous estimates of total NOx emissions for HDDV fleet may be significantly underestimated. The new estimate in total NOx emissions for the Beijing HDDV fleet in 2009 is 37.0 Gg, an increase of 45% compared to the previous study. Further, we estimate that the total NOx emissions for the national HDDV fleet in 2009 are approximately 4.0 Tg, higher by 1.0 Tg (equivalent to 18% of total NOx emissions for vehicle fleet in 2009) than that estimated in the official report. This would also result in 4% increase in estimation of national anthropogenic NOx emissions. More effective control measures (such as promotion of CNG buses and a new in-use compliance testing program) are urged to secure the goal of total NOxmitigation for the HDDV fleet in the future.

The challenge to NOx emission control for heavy-duty diesel vehicles in China

NASA Astrophysics Data System (ADS)

Wu, Y.; Zhang, S. J.; Li, M. L.; Ge, Y. S.; Shu, J. W.; Zhou, Y.; Xu, Y. Y.; Hu, J. N.; Liu, H.; Fu, L. X.; He, K. B.; Hao, J. M.

2012-10-01

China's new "Twelfth Five-Year Plan" set a target for total NOx emission reduction of 10% for the period of 2011-2015. Heavy-duty diesel vehicles (HDDVs) have been considered a major contributor to NOx emissions in China. Beijing initiated a comprehensive vehicle test program in 2008. This program included a sub-task for measuring on-road emission profiles of hundreds of HDDVs using portable emission measurement systems (PEMS). The major finding is that neither the on-road distance-specific (g km-1) nor brake-specific (g kWh-1) NOx emission factors for diesel buses and heavy-duty diesel trucks improved in most cases as emission standards became more stringent. For example, the average NOx emission factors for Euro II, Euro III and Euro IV buses are 11.3 ± 3.3 g km-1, 12.5 ± 1.3 g km-1, and 11.8 ± 2.0 g km-1, respectively. No statistically significant difference in NOx emission factors was observed between Euro II and III buses. Even for Euro IV buses equipped with SCR systems, the NOx emission factors are similar to Euro III buses. The data regarding real-time engine performance of Euro IV buses suggest the engine certification cycles did not reflect their real-world operating conditions. These new on-road test results indicate that previous estimates of total NOx emissions for HDDV fleet may be significantly underestimated. The new estimate in total NOx emissions for the Beijing HDDV fleet in 2009 is 37.0 Gg, an increase of 45% compared to the previous study. Further, we estimate that the total NOx emissions for the national HDDV fleet in 2009 are approximately 4.0 Tg, higher by 1.0 Tg (equivalent to 18% of total NOx emissions for vehicle fleet in 2009) than that estimated in the official report. This would also result in 4% increase in estimation of national anthropogenic NOx emissions. More effective control measures (such as promotion of CNG buses and a new in-use compliance testing program) are urged to secure the goal of total NOx mitigation for the HDDV fleet 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.

Measurement of greenhouse gas emissions from agricultural sites using open-path optical remote sensing method.

PubMed

Ro, Kyoung S; Johnson, Melvin H; Varma, Ravi M; Hashmonay, Ram A; Hunt, Patrick

2009-08-01

Improved characterization of distributed emission sources of greenhouse gases such as methane from concentrated animal feeding operations require more accurate methods. One promising method is recently used by the USEPA. It employs a vertical radial plume mapping (VRPM) algorithm using optical remote sensing techniques. We evaluated this method to estimate emission rates from simulated distributed methane sources. A scanning open-path tunable diode laser was used to collect path-integrated concentrations (PICs) along different optical paths on a vertical plane downwind of controlled methane releases. Each cycle consists of 3 ground-level PICs and 2 above ground PICs. Three- to 10-cycle moving averages were used to reconstruct mass equivalent concentration plum maps on the vertical plane. The VRPM algorithm estimated emission rates of methane along with meteorological and PIC data collected concomitantly under different atmospheric stability conditions. The derived emission rates compared well with actual released rates irrespective of atmospheric stability conditions. The maximum error was 22 percent when 3-cycle moving average PICs were used; however, it decreased to 11% when 10-cycle moving average PICs were used. Our validation results suggest that this new VRPM method may be used for improved estimations of greenhouse gas emission from a variety of agricultural sources.

Farm-scale testing of soybean peroxidase and calcium peroxide for surficial swine manure treatment and mitigation of odorous VOCs, ammonia and hydrogen sulfide emissions

NASA Astrophysics Data System (ADS)

Maurer, Devin L.; Koziel, Jacek A.; Bruning, Kelsey; Parker, David B.

2017-10-01

The swine industry, regulatory agencies, and the public are interested in farm-tested methods for controlling gaseous emissions from swine barns. In earlier lab- and pilot-scale studies, a renewable catalyst consisting of soybean peroxidase (SBP) mixed with calcium peroxide (CaO2) was found to be effective in mitigating gaseous emissions from swine manure. Thus, a farm-scale experiment was conducted at the university's 178-pig, shallow-pit, mechanically-ventilated swine barn to evaluate SBP/CaO2 as a surficial manure pit additive under field conditions. The SBP was applied once at the beginning of the 42-day experiment at an application rate of 2.28 kg m-2 with 4.2% CaO2 added by weight. Gas samples were collected from the primary barn exhaust fans. As compared to the control, significant reductions in gaseous emissions were observed for ammonia (NH3, 21.7%), hydrogen sulfide (H2S, 79.7%), n-butyric acid (37.2%), valeric acid (47.7%), isovaleric acid (39.3%), indole (31.2%), and skatole (43.5%). Emissions of dimethyl disulfide/methanethiol (DMDS/MT) increased by 30.6%. Emissions of p-cresol were reduced by 14.4% but were not statistically significant. There were no significant changes to the greenhouse gas (GHG) emissions of methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O). The total (material + labor) treatment cost was 2.62 per marketed pig, equivalent to 1.5% of the pig market price. The cost of CaO2 catalyst was ∼60% of materials cost. The cost of soybean hulls (SBP source) was 0.60 per marketed pig, i.e., only 40% of materials cost.

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or superior emissions reductions to existing clean fuel or hybrid electric technologies. (4) The Federal share...) Batteries; (v) Alcohol-based fuels; (vi) Hybrid electric; (vii) Fuel cells; (viii) Clean diesel, to the...

40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy and carbon-related exhaust emission...

Code of Federal Regulations, 2011 CFR

2011-07-01

... exhaust emission values from the tests performed using gasoline or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy and carbon-related exhaust emission values from the tests performed using alcohol or natural gas test fuel. (b) If only one equivalent petroleum-based fuel economy...

Performance and Emission Characteristics of Diesel Engine Fueled with Ethanol-Diesel Blends in Different Altitude Regions

PubMed Central

Lei, Jilin; Bi, Yuhua; Shen, Lizhong

2011-01-01

In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel engine fueled with pure diesel (as prototype) and ethanol-diesel blends (E10, E15, E20 and E30) under different atmospheric pressures (81 kPa, 90 kPa and 100 kPa). The experimental results indicate that the equivalent brake-specific fuel consumption (BSFC) of ethanol-diesel blends are better than that of diesel under different atmospheric pressures and that the equivalent BSFC gets great improvement with the rise of atmospheric pressure when the atmospheric pressure is lower than 90 kPa. At 81 kPa, both HC and CO emissions rise greatly with the increasing engine speeds and loads and addition of ethanol, while at 90 kPa and 100 kPa their effects on HC and CO emissions are slightest. The changes of atmospheric pressure and mix proportion of ethanol have no obvious effect on NOx emissions. Smoke emissions decrease obviously with the increasing percentage of ethanol in blends, especially atmospheric pressure below 90 kPa. PMID:21234367

Performance and emission characteristics of diesel engine fueled with ethanol-diesel blends in different altitude regions.

PubMed

Lei, Jilin; Bi, Yuhua; Shen, Lizhong

2011-01-01

In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel engine fueled with pure diesel (as prototype) and ethanol-diesel blends (E10, E15, E20 and E30) under different atmospheric pressures (81 kPa, 90 kPa and 100 kPa). The experimental results indicate that the equivalent brake-specific fuel consumption (BSFC) of ethanol-diesel blends are better than that of diesel under different atmospheric pressures and that the equivalent BSFC gets great improvement with the rise of atmospheric pressure when the atmospheric pressure is lower than 90 kPa. At 81 kPa, both HC and CO emissions rise greatly with the increasing engine speeds and loads and addition of ethanol, while at 90 kPa and 100 kPa their effects on HC and CO emissions are slightest. The changes of atmospheric pressure and mix proportion of ethanol have no obvious effect on NO(x) emissions. Smoke emissions decrease obviously with the increasing percentage of ethanol in blends, especially atmospheric pressure below 90 kPa.

Extending cost–benefit analysis for the sustainability impact of inter-urban Intelligent Transport Systems

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

Kolosz, Ben, E-mail: kolosz27@gmail.com; Grant-Muller, Susan, E-mail: S.M.Grant-Muller@its.leeds.ac.uk

The paper reports research involving three cost–benefit analyses performed on different ITS schemes (Active Traffic Management, Intelligent Speed Adaptation and the Automated Highway System) on one of the UK's busiest highways — the M42. The environmental scope of the assets involved is widened to take into account the possibility of new technology linked by ICT and located within multiple spatial regions. The areas focused on in the study were data centre energy emissions, the embedded emissions of the road-side infrastructure, vehicle tailpipe emissions, additional hardware required by the vehicles (if applicable) and safety, and all aspects of sustainability. Dual discountingmore » is applied which aims to provide a separate discount rate for environmental elements. For ATM, despite the energy costs of the data centre, the initial implementation costs and mitigation costs of its embedded emissions, a high cost–benefit ratio of 5.89 is achieved, although the scheme becomes less effective later on its lifecycle due to rising costs of energy. ISA and AHS generate a negative result, mainly due to the cost of getting the vehicle on the road. In order to negate these costs, the pricing of the vehicle should be scaled depending upon the technology that is outfitted. Retrofitting on vehicles without the technology should be paid for by the driver. ATM will offset greenhouse gas emissions by 99 kt of CO{sub 2} equivalency over a 25 year lifespan. This reduction has taken into account the expected improvement in vehicle technology. AHS is anticipated to save 280 kt of CO{sub 2} equivalency over 15 years of operational usage. However, this offset is largely dependent on assumptions such as the level of market penetration. - Highlights: • Three cost–benefit analyses are applied to inter-urban intelligent transport. • For ATM, a high cost–benefit ratio of 5.89 is achieved. • ATM offsets greenhouse gas emissions by 99 kt of CO{sub 2} equivalency over 25 years. • ISA and AHS generate a negative result due to vehicle implementation costs. • AHS is anticipated to save 280 kt of CO{sub 2} equivalency over 15 years.« less

Abatement of Xenon and Iodine Emissions from Medical Isotope Production Facilities

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

Doll, Charles G.; Sorensen, Christina M.; Bowyer, Ted W.

2014-04-01

The capability of the International Monitoring System (IMS) to detect xenon from underground nuclear explosions is dependent on the radioactive xenon background. Adding to the background, medical isotope production (MIP) by fission releases several important xenon isotopes including xenon-133 and iodine-133 that decays to xenon-133. The amount of xenon released from these facilities may be equivalent to or exceed that released from an underground nuclear explosion. Thus the release of gaseous fission products within days of irradiation makes it difficult to distinguish MIP emissions from a nuclear explosion. In addition, recent shortages in molybdenum-99 have created interest and investment opportunitiesmore » to design and build new MIP facilities in the United States and throughout the world. Due to the potential increase in the number of MIP facilities, a discussion of abatement technologies provides insight into how the problem of emission control from MIP facilities can be tackled. A review of practices is provided to delineate methods useful for abatement of medical isotopes.« less

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.

Lean burn natural gas fueled S.I. engine and exhaust emissions

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

Varde, K.S.; Patro, N.; Drouillard, K.

1995-12-31

An experimental study was undertaken to study exhaust emission from a lean-burn natural gas spark ignition engine. The possibility that such an engine may help to reduce exhaust emissions substantially by taking advantage of natural gas fuel properties, such as its antiknock properties and extended lean flammability limit compared to gasoline, was the main motivation behind the investigation. A four cylinder, automotive type spark ignition engine was used in the investigation. The engine was converted to operate on natural gas by replacing its fuel system with a gaseous carburetion system. A 3-way metal metrix catalytic converter was used in themore » engine exhaust system to reduce emission levels. The engine operated satisfactorily at an equivalence ratio as lean as 0.6, at all speeds and loads. As a result NOx emissions were significantly reduced. However, hydrocarbon emissions were high, particularly at very lean conditions and light loads. Most of these hydrocarbons were made up of methane with small concentrations of ethane and propane. Coefficient of variations in hydrocarbons were generally high at very lean operating conditions and light loads, but decreased with increasing equivalence ratio and engine speed. Methane concentrations in the engine exhaust decreased with increasing load and equivalence ratio. At lean air-to-fuel ratios and light loads oxidation of methane in the catalyst was substantially limited and no NOx reduction was achieved. In addition, the proportion of nitric oxide in oxides of nitrogen increased with increasing amount of NOx in the engine exhaust. A major problem encountered in the study was the inability of the fuel system to maintain near constant air-to-fuel ratios at steady operating conditions.« less

No evidence for Lyman α emission in spectroscopy of z > 7 candidate galaxies

NASA Astrophysics Data System (ADS)

Caruana, Joseph; Bunker, Andrew J.; Wilkins, Stephen M.; Stanway, Elizabeth R.; Lacy, Mark; Jarvis, Matt J.; Lorenzoni, Silvio; Hickey, Samantha

2012-12-01

We present Gemini/Gemini Near Infrared Spectrograph (GNIRS) spectroscopic observations of four z-band (z ≈ 7) dropout galaxies and Very Large Telescope (VLT)/XSHOOTER observations of one z-band dropout and three Y-band (z ≈ 8-9) dropout galaxies in the Hubble Ultra Deep Field, which were selected with Wide Field Camera 3 imaging on the Hubble Space Telescope. We find no evidence of Lyman α emission with a typical 5σ sensitivity of 5 × 10-18 erg cm-2 s-1, and use the upper limits on Lyman α flux and the broad-band magnitudes to constrain the rest-frame equivalent widths for this line emission. Accounting for incomplete spectral coverage, we survey 3.0 z-band dropouts and 2.9 Y-band dropouts to a Lyman α rest-frame equivalent width limit >120 Å (for an unresolved emission line); for an equivalent width limit of 50 Å the effective numbers of drop-outs surveyed fall to 1.2 z-band drop-outs and 1.5 Y-band drop-outs. A simple model where the fraction of high rest-frame equivalent width emitters follows the trend seen at z = 3-6.5 is inconsistent with our non-detections at z = 7-9 at the ≈1σ level for spectrally unresolved lines, which may indicate that a significant neutral H I fraction in the intergalactic medium suppresses the Lyman α line in z-drop and Y-drop galaxies at z > 7. Based on observations collected at the European Organization for Astronomical Research in the Southern Hemisphere, Chile, as part of programme 086.A-0968(B).

The injury and cumulative effects on human skin by UV exposure from artificial fluorescence emission.

PubMed

Tian, Yan; Liu, Wei; Niu, TianHui; Dai, CaiHong; Li, Xiaoxin; Cui, Caijuan; Zhao, Xinyan; E, Yaping; Lu, Hui

2014-01-01

The injury and cumulative effects of UV emission from fluorescence lamp were studied. UV intensity from fluorescence lamp was measured, and human skin samples (hips, 10 volunteers) were exposed to low-dose UV irradiation (three times per week for 13 consecutive weeks). Three groups were examined: control group without UV radiation; low-dose group with a cumulative dose of 50 J cm(-2) which was equivalent to irradiation of the face during indoor work for 1.5 years; and high-dose group with 1000 J cm(-2) cumulative dose equivalent to irradiation of the face during outdoor activities for 1 year. Specific indicators were measured before and after UVA irradiation. The findings showed that extending the low-dose UVA exposure decreased the skin moisture content and increased the transepidermal water loss as well as induced skin color changes (decreased L* value, increased M index). Furthermore, irradiated skin showed an increased thickness of cuticle and epidermis, skin edema, light color and unclear staining collagen fibers in the dermis, and elastic fiber fragmentation. In addition, MMP-1, p53 and SIRT1 expression was also increased. Long-term exposure of low-dose UVA radiation enhanced skin photoaging. The safety of the fluorescent lamp needs our attention. © 2014 The American Society of Photobiology.

Comparing otoacoustic emissions evoked by chirp transients with constant absorbed sound power and constant incident pressure magnitude.

PubMed

Keefe, Douglas H; Feeney, M Patrick; Hunter, Lisa L; Fitzpatrick, Denis F

2017-01-01

Human ear-canal properties of transient acoustic stimuli are contrasted that utilize measured ear-canal pressures in conjunction with measured acoustic pressure reflectance and admittance. These data are referenced to the tip of a probe snugly inserted into the ear canal. Promising procedures to calibrate across frequency include stimuli with controlled levels of incident pressure magnitude, absorbed sound power, and forward pressure magnitude. An equivalent pressure at the eardrum is calculated from these measured data using a transmission-line model of ear-canal acoustics parameterized by acoustically estimated ear-canal area at the probe tip and length between the probe tip and eardrum. Chirp stimuli with constant incident pressure magnitude and constant absorbed sound power across frequency were generated to elicit transient-evoked otoacoustic emissions (TEOAEs), which were measured in normal-hearing adult ears from 0.7 to 8 kHz. TEOAE stimuli had similar peak-to-peak equivalent sound pressure levels across calibration conditions. Frequency-domain TEOAEs were compared using signal level, signal-to-noise ratio (SNR), coherence synchrony modulus (CSM), group delay, and group spread. Time-domain TEOAEs were compared using SNR, CSM, instantaneous frequency and instantaneous bandwidth. Stimuli with constant incident pressure magnitude or constant absorbed sound power across frequency produce generally similar TEOAEs up to 8 kHz.

Experimental study of the effects of flameholder geometry on emissions and performance of lean premixed combustors

NASA Technical Reports Server (NTRS)

Roffe, G.; Venkataramani, K. S.

1978-01-01

Emissions of NOx, CO, and unburned hydrocarbons (UHC) are reported for a lean premixed propane-air system at inlet conditions of 800K and 1MPa using twelve flameholder designs. The flameholders tested represent six design concepts with two values of blockage for each concept. Data were obtained at reference velocities of 35 m/s, 25 m/s and 20 m/s at combustor stations 10 cm and 30 cm downstream of the flameholders. Flameholder pressure drop was found to be a principal determinant of emissions performance. Designs producing larger pressure drops also produced less NOx, CO, and UHC emissions. The lean stability limit equivalence ratio was found to be approximately 0.35 for all designs. Flashback velocities (axial components in the flameholder passages) varied between 30 m/s and 40 m/s. A perforated plate flameholder was operated with a velocity as low as 23 m/s through the perforations at equivalence ratio 0.7 without producing flashback.

Increased photon emission from the head while imagining light in the dark is correlated with changes in electroencephalographic power: support for Bókkon's biophoton hypothesis.

PubMed

Dotta, B T; Saroka, K S; Persinger, M A

2012-04-04

Bókkon's hypothesis that photons released from chemical processes within the brain produce biophysical pictures during visual imagery has been supported experimentally. In the present study measurements by a photomultiplier tube also demonstrated significant increases in ultraweak photon emissions (UPEs) or biophotons equivalent to about 5×10(-11)W/m(2) from the right sides of volunteer's heads when they imagined light in a very dark environment compared to when they did not. Simultaneous variations in regional quantitative electroencephalographic spectral power (μV(2)/Hz) and total energy in the range of ∼10(-12)J from concurrent biophoton emissions were strongly correlated (r=0.95). The calculated energy was equivalent to that associated with action potentials from about 10(7) cerebral cortical neurons. We suggest these results support Bókkon's hypothesis that specific visual imagery is strongly correlated with ultraweak photon emission coupled to brain activity. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Effect of exhaust gas recirculation on emissions from a flame-tube combustor using Liquid Jet A fuel

NASA Technical Reports Server (NTRS)

Marek, C. J.; Tacina, R. R.

1976-01-01

The effects of uncooled exhaust gas recirculation as an inert diluent on emissions of oxides of nitrogen (NO + NO2) and on combustion efficiency were investigated. Ratios of recirculated combustion products to inlet airflow were varied from 10 to 80 percent by using an inlet air ejector nozzle. Liquid Jet A fuel was used. The flame-tube combustor was 10.2 cm in diameter. It was operated with and without a flameholder present. The combustor pressure was maintained constant at 0.5 MPa. The equivalence ratio was varied from 0.3 to 1.0. The inlet air temperature was varied from 590 to 800 K, and the reference velocity from 10 to 30 m/sec. Increasing the percent recirculation from 10 to 25 had the following effects: (1) the peak NOx emission was decreased by 37 percent, from 8 to 5 g NO2/kg fuel, at an inlet air temperature of 590 K and a reference velocity of 15 m/sec; (2) the combustion efficiency was increased, particularly at the higher equivalence ratios; and (3) for a high combustion efficiency of greater than 99.5 percent, the range of operation of the combustor was nearly doubled in terms of equivalence ratio. Increasing the recirculation from 25 to 50 percent did not change the emissions significantly.

40 CFR 60.2110 - What operating limits must I meet and by when?

Code of Federal Regulations, 2013 CFR

2013-07-01

... for Commercial and Industrial Solid Waste Incineration Units Emission Limitations and Operating Limits... capable of reading PM concentrations from zero to a level equivalent to at least two times your allowable... of the instrument must be capable of reading PM concentration from zero to a level equivalent to two...

NOx Emissions Performance and Correlation Equations for a Multipoint LDI Injector

NASA Technical Reports Server (NTRS)

He, Zhuohui J.; Chang, Clarence T.; Follen, Caitlin E.

2014-01-01

Lean Direct Injection (LDI) is a combustor concept that reduces nitrogen oxides (NOx) emissions. This paper looks at a 3-zone multipoint LDI concept developed by Parker Hannifin Corporation. The concept was tested in a flame-tube test facility at NASA Glenn Research Center. Due to test facility limitations, such as inlet air temperature and pressure, the flame-tube test was not able to cover the full set of engine operation conditions. Three NOx correlation equations were developed based on assessing NOx emissions dependencies on inlet air pressure (P3), inlet air temperature (T3), and fuel air equivalence ratio (phi) to estimate the NOx emissions at the unreachable high engine power conditions. As the results, the NOx emissions are found to be a strong function of combustion inlet air temperature and fuel air equivalence ratio but a weaker function of inlet air pressure. With these three equations, the NOx emissions performance of this injector concept is calculated as a 66 percent reduction relative to the ICAO CAEP-6 standard using a 55:1 pressure-ratio engine cycle. Uncertainty in the NOx emissions estimation increases as the extrapolation range departs from the experimental conditions. Since maximum inlet air pressure tested was less than 50 percent of the full power engine inlet air pressure, a future experiment at higher inlet air pressure conditions is needed to confirm the NOx emissions dependency on inlet air pressure.

NOx Emissions Performance and Correlation Equations for a Multipoint LDI Injector

NASA Technical Reports Server (NTRS)

He, Zhuohui Joe; Chang, Clarence T.; Follen, Caitlin E.

2015-01-01

Lean Direct Injection (LDI) is a combustor concept that reduces nitrogen oxides (NOx) emissions.This paper looks at a 3-zone multipoint LDI concept developed by Parker Hannifin Corporation. The concept was tested in a flame-tube test facility at NASA Glenn Research Center. Due to test facility limitations, such as inlet air temperature and pressure, the flame-tube test was not able to cover the full set of engine operation conditions. Three NOx correlation equations were developed based on assessing NOx emissions dependencies on inlet air pressure (P3), inlet air temperature (T3), and fuel air equivalence ratio(theta) to estimate the NOx emissions at the unreachable high engine power conditions. As the results, the NOx emissions are found to be a strong function of combustion inlet air temperature and fuel air equivalence ratio but a weaker function of inlet air pressure. With these three equations, the NOx emissions performance of this injector concept is calculated as a 66 reduction relative to the ICAO CAEP-6 standard using a 55:1 pressure-ratio engine cycle. Uncertainty in the NOx emissions estimation increases as the extrapolation range departs from the experimental conditions. Since maximum inlet air pressure tested was less than 50 of the full power engine inlet air pressure, a future experiment at higher inlet air pressure conditions is needed to confirm the NOx emissions dependency on inlet air pressure.

NOx Emissions Performance and Correlation Equations for a Multipoint LDI Injector

NASA Technical Reports Server (NTRS)

He, Zhuohui J.; Chang, Clarence T.; Follen, Caitlin E.

2015-01-01

Lean Direct Injection (LDI) is a combustor concept that reduces nitrogen oxides (NOx) emissions. This paper looks at a 3-zone multipoint LDI concept developed by Parker Hannifin Corporation. The concept was tested in a flame-tube test facility at NASA Glenn Research Center. Due to test facility limitations, such as inlet air temperature and pressure, the flame-tube test was not able to cover the full set of engine operation conditions. Three NOx correlation equations were developed based on assessing NOx emissions dependencies on inlet air pressure (P3), inlet air temperature (T3), and fuel air equivalence ratio (?) to estimate the NOx emissions at the unreachable high engine power conditions. As the results, the NOx emissions are found to be a strong function of combustion inlet air temperature and fuel air equivalence ratio but a weaker function of inlet air pressure. With these three equations, the NOx emissions performance of this injector concept is calculated as a 66% reduction relative to the ICAO CAEP-6 standard using a 55:1 pressure-ratio engine cycle. Uncertainty in the NOx emissions estimation increases as the extrapolation range departs from the experimental conditions. Since maximum inlet air pressure tested was less than 50% of the full power engine inlet air pressure, a future experiment at higher inlet air pressure conditions is needed to confirm the NOx emissions dependency on inlet air pressure.

NOx Emissions Performance and Correlation Equations for a Multipoint LDI Injector

NASA Technical Reports Server (NTRS)

He, Zhuohui J.; Chang, Clarence T.; Follen, Caitlin E.

2014-01-01

Lean Direct Injection (LDI) is a combustor concept that reduces nitrogen oxides (NOx) emissions. This paper looks at a 3-zone multipoint LDI concept developed by Parker Hannifin Corporation. The concept was tested in a flame-tube test facility at NASA Glenn Research Center. Due to test facility limitations, such as inlet air temperature and pressure, the flame-tube test was not able to cover the full set of engine operation conditions. Three NOx correlation equations were developed based on assessing NOx emissions dependencies on inlet air pressure (P3), inlet air temperature (T3), and fuel air equivalence ratio (?) to estimate the NOx emissions at the unreachable high engine power conditions. As the results, the NOx emissions are found to be a strong function of combustion inlet air temperature and fuel air equivalence ratio but a weaker function of inlet air pressure. With these three equations, the NOx emissions performance of this injector concept is calculated as a 66 percent reduction relative to the ICAO CAEP-6 standard using a 55:1 pressure-ratio engine cycle. Uncertainty in the NOx emissions estimation increases as the extrapolation range departs from the experimental conditions. Since maximum inlet air pressure tested was less than 50 percent of the full power engine inlet air pressure, a future experiment at higher inlet air pressure conditions is needed to confirm the NOx emissions dependency on inlet air pressure.

The Relationship between Stellar Populations and Lyα Emission in Lyman Break Galaxies

NASA Astrophysics Data System (ADS)

Kornei, Katherine A.; Shapley, Alice E.; Erb, Dawn K.; Steidel, Charles C.; Reddy, Naveen A.; Pettini, Max; Bogosavljević, Milan

2010-03-01

We present the results of a photometric and spectroscopic survey of 321 Lyman break galaxies (LBGs) at z~ 3 to investigate systematically the relationship between Lyα emission and stellar populations. Lyα equivalent widths (W Lyα) were calculated from rest-frame UV spectroscopy and optical/near-infrared/Spitzer photometry was used in population synthesis modeling to derive the key properties of age, dust extinction, star formation rate (SFR), and stellar mass. We directly compare the stellar populations of LBGs with and without strong Lyα emission, where we designate the former group (W Lyα>= 20 Å) as Lyα emitters (LAEs) and the latter group (W Lyα< 20 Å) as non-LAEs. This controlled method of comparing objects from the same UV luminosity distribution represents an improvement over previous studies in which the stellar populations of LBGs and narrowband-selected LAEs were contrasted, where the latter were often intrinsically fainter in broadband filters by an order of magnitude simply due to different selection criteria. Using a variety of statistical tests, we find that Lyα equivalent width and age, SFR, and dust extinction, respectively, are significantly correlated in the sense that objects with strong Lyα emission also tend to be older, lower in SFR, and less dusty than objects with weak Lyα emission, or the line in absorption. We accordingly conclude that, within the LBG sample, objects with strong Lyα emission represent a later stage of galaxy evolution in which supernovae-induced outflows have reduced the dust covering fraction. We also examined the hypothesis that the attenuation of Lyα photons is lower than that of the continuum, as proposed by some, but found no evidence to support this picture. Based, in part, on data obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA, and was made possible by the generous financial support of the W.M. Keck Foundation.

40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

Code of Federal Regulations, 2013 CFR

2013-07-01

... values from the tests performed using gasoline or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and carbon-related exhaust emission values from the tests performed using alcohol or natural gas test fuel. (b) If only one equivalent petroleum-based fuel economy value...

40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

Code of Federal Regulations, 2014 CFR

2014-07-01

... values from the tests performed using gasoline or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and carbon-related exhaust emission values from the tests performed using alcohol or natural gas test fuel. (b) If only one equivalent petroleum-based fuel economy value...

40 CFR 600.206-12 - Calculation and use of FTP-based and HFET-based fuel economy, CO2 emissions, and carbon-related...

Code of Federal Regulations, 2012 CFR

2012-07-01

... values from the tests performed using gasoline or diesel test fuel. (ii) Calculate the city, highway, and combined fuel economy, CO2 emissions, and carbon-related exhaust emission values from the tests performed using alcohol or natural gas test fuel. (b) If only one equivalent petroleum-based fuel economy value...

Nitrogen trifluoride global emissions estimated from updated atmospheric measurements

PubMed Central

Arnold, Tim; Harth, Christina M.; Mühle, Jens; Manning, Alistair J.; Salameh, Peter K.; Kim, Jooil; Ivy, Diane J.; Steele, L. Paul; Petrenko, Vasilii V.; Severinghaus, Jeffrey P.; Baggenstos, Daniel; Weiss, Ray F.

2013-01-01

Nitrogen trifluoride (NF3) has potential to make a growing contribution to the Earth’s radiative budget; however, our understanding of its atmospheric burden and emission rates has been limited. Based on a revision of our previous calibration and using an expanded set of atmospheric measurements together with an atmospheric model and inverse method, we estimate that the global emissions of NF3 in 2011 were 1.18 ± 0.21 Gg⋅y−1, or ∼20 Tg CO2-eq⋅y−1 (carbon dioxide equivalent emissions based on a 100-y global warming potential of 16,600 for NF3). The 2011 global mean tropospheric dry air mole fraction was 0.86 ± 0.04 parts per trillion, resulting from an average emissions growth rate of 0.09 Gg⋅y−2 over the prior decade. In terms of CO2 equivalents, current NF3 emissions represent between 17% and 36% of the emissions of other long-lived fluorinated compounds from electronics manufacture. We also estimate that the emissions benefit of using NF3 over hexafluoroethane (C2F6) in electronics manufacture is significant—emissions of between 53 and 220 Tg CO2-eq⋅y−1 were avoided during 2011. Despite these savings, total NF3 emissions, currently ∼10% of production, are still significantly larger than expected assuming global implementation of ideal industrial practices. As such, there is a continuing need for improvements in NF3 emissions reduction strategies to keep pace with its increasing use and to slow its rising contribution to anthropogenic climate forcing. PMID:23341630

[Spectral emissivity of thin films].

PubMed

Zhong, D

2001-02-01

In this paper, the contribution of multiple reflections in thin film to the spectral emissivity of thin films of low absorption is discussed. The expression of emissivity of thin films derived here is related to the thin film thickness d and the optical constants n(lambda) and k(lambda). It is shown that in the special case d-->infinity the emissivity of thin films is equivalent to that of the bulk material. Realistic numerical and more precise general numerical results for the dependence of the emissivity on d, n(lambda) and k(lambda) are given.

Potential contributions of food consumption patterns to climate change.

PubMed

Carlsson-Kanyama, Annika; González, Alejandro D

2009-05-01

Anthropogenic warming is caused mainly by emissions of greenhouse gases (GHGs), such as carbon dioxide, methane, and nitrous oxide, with agriculture as a main contributor for the latter 2 gases. Other parts of the food system contribute carbon dioxide emissions that emanate from the use of fossil fuels in transportation, processing, retailing, storage, and preparation. Food items differ substantially when GHG emissions are calculated from farm to table. A recent study of approximately 20 items sold in Sweden showed a span of 0.4 to 30 kg CO(2) equivalents/kg edible product. For protein-rich food, such as legumes, meat, fish, cheese, and eggs, the difference is a factor of 30 with the lowest emissions per kilogram for legumes, poultry, and eggs and the highest for beef, cheese, and pork. Large emissions for ruminants are explained mainly by methane emissions from enteric fermentation. For vegetables and fruits, emissions usually are

Effects of the herbicides prosulfuron and metolachlor on fluxes of CO2, N2O, and CH4 in a fertilized Colorado grassland soil

USGS Publications Warehouse

Kinney, C.A.; Mosier, A.R.; Ferrer, I.; Furlong, E.T.; Mandernack, K.W.

2004-01-01

The effect that pesticides have on trace gas production and consumption in agricultural soils is often overlooked. Independent field and laboratory experiments were used to measure the effects that the commonly used herbicides prosulfuron and metolachlor have on trace gas fluxes (CO2, N2O, and CH4) from fertilized soil of the Colorado shortgrass steppe. Separate sample plots (1 m2) on tilled and no-till soil at the sites included the following treatments: 1) a control without fertilizer or herbicide, 2) a fertilized (NH4NO3 equivalent to 244 kg ha-1) control without herbicide, 3) and fertilized plots amended with an herbicide (prosulfuron equivalent to 0.46 kg ha-1 57% by weight active ingredient or metolachlor equivalent to 5.7 L ha-1, 82.4% by weight active ingredient). During an initial study of one year duration, measurement of gas exchange revealed that prosulfuron-amendment stimulated N2O emissions and CH4 consumption by as much as 1600% and 1300% during a single measurement, respectively. During a second set of flux measurements beginning in August 2001, more frequent weekly measurements were made during a twelve week period. From this second study an increased N2O efflux and CH4 uptake occurred after a 7-week lag period that persisted for about 5 weeks. These changes in gas flux amounted to an overall increase of 41% and 30% for N2O emission and CH4 consumption, respectively. The co-occurrence of stimulated N2O and CH4 fluxes suggests a similar cause that is related to prosulfuron degradation. Evidence suggested that prosulfuron degradation stimulated microbial activity responsible for trace gas flux. Ultimately, prosulfuron-amendment led to an ???50% reduction in the global warming potential from N2O and CH4 fluxes at this field site, which is equivalent to a reduction of the global warming potential of 0.18 mols CO2 m-2 d-1 from these gases. Metolachlor application did not significantly affect the trace gas fluxes measured. These results demonstrate the potential impact that pesticides have on trace gas fluxes from agricultural soils, which could mean that the effects of other agricultural practices have been over or under estimated. Copyright 2004 by the American Geophysical Union.

Residential proximity to industrial combustion facilities and risk of non-Hodgkin lymphoma: a case–control study

PubMed Central

2013-01-01

Background Residence near municipal solid waste incinerators, a major historical source of dioxin emissions, has been associated with increased risk of non-Hodgkin lymphoma (NHL) in European studies. The aim of our study was to evaluate residence near industrial combustion facilities and estimates of dioxin emissions in relation to NHL risk in the United States. Methods We conducted a population-based case–control study of NHL (1998–2000) in four National Cancer Institute-Surveillance Epidemiology and End Results centers (Detroit, Iowa, Los Angeles, Seattle). Residential histories 15 years before diagnosis (similar date for controls) were linked to an Environmental Protection Agency database of dioxin-emitting facilities for 969 cases and 749 controls. We evaluated proximity (3 and 5 km) to 10 facility types that accounted for >85% of U.S. emissions and a distance-weighted average emission index (AEI [ng toxic equivalency quotient (TEQ)/year]). Results Proximity to any dioxin-emitting facility was not associated with NHL risk (3 km OR = 1.0, 95% CI 0.8-1.3). Risk was elevated for residence near cement kilns (5 km OR = 1.7, 95% CI 0.8-3.3; 3 km OR = 3.8, 95% CI 1.1-14.0) and reduced for residence near municipal solid waste incinerators (5 km OR = 0.5, 95% CI 0.3-0.9; 3 km OR = 0.3, 95% CI 0.1-1.4). The AEI was not associated with risk of NHL overall. Risk for marginal zone lymphoma was increased for the highest versus lowest quartile (5 km OR = 2.6, 95% CI 1.0-6.8; 3 km OR = 3.0, 95% CI 1.1-8.3). Conclusions Overall, we found no association with residential exposure to dioxins and NHL risk. However, findings for high emissions and marginal zone lymphoma and for specific facility types and all NHL provide some evidence of an association and deserve future study. PMID:23433489

The Market Triumph of Ecotourism: An Economic Investigation of the Private and Social Benefits of Competing Land Uses in the Peruvian Amazon

PubMed Central

Kirkby, Christopher A.; Giudice-Granados, Renzo; Day, Brett; Turner, Kerry; Velarde-Andrade, Luz Marina; Dueñas-Dueñas, Agusto; Lara-Rivas, Juan Carlos; Yu, Douglas W.

2010-01-01

Annual revenue flow to developing countries for ecotourism (or nature-based tourism) could be as large as US$ 210×1012, providing an enormous financial incentive against habitat loss and exploitation. However, is ecotourism the most privately and/or socially valuable use of rainforest land? The question is rarely answered because the relevant data, estimates of profits and fixed costs, are rarely available. We present a social cost-benefit analysis of land use in an ecotourism cluster in the Tambopata region of Amazonian Peru. The net present value of ecotourism-controlled land is given by the producer surplus (profits plus fixed costs of ecotourism lodges): US$ 1,158 ha−1, which is higher than all currently practiced alternatives, including unsustainable logging, ranching, and agriculture. To our knowledge, this is the first sector-wide study of profitability and producer surplus in a developing-country ecotourism sector and the first to compare against equivalent measures for a spectrum of alternative uses. We also find that ecotourism-controlled land sequesters between 5.3 to 8.7 million tons of above-ground carbon, which is equivalent to between 3000–5000 years of carbon emissions from the domestic component of air and surface travel between the gateway city of Cusco and the lodges, at 2005 emission rates. Ecotourism in Tambopata has successfully monetized the hedonic value of wild nature in Amazonian Peru, and justifies the maintenance of intact rainforest over all alternative uses on narrow economic grounds alone. PMID:20927377

The market triumph of ecotourism: an economic investigation of the private and social benefits of competing land uses in the Peruvian Amazon.

PubMed

Kirkby, Christopher A; Giudice-Granados, Renzo; Day, Brett; Turner, Kerry; Velarde-Andrade, Luz Marina; Dueñas-Dueñas, Agusto; Lara-Rivas, Juan Carlos; Yu, Douglas W

2010-09-29

Annual revenue flow to developing countries for ecotourism (or nature-based tourism) could be as large as US$ 210×10(12), providing an enormous financial incentive against habitat loss and exploitation. However, is ecotourism the most privately and/or socially valuable use of rainforest land? The question is rarely answered because the relevant data, estimates of profits and fixed costs, are rarely available. We present a social cost-benefit analysis of land use in an ecotourism cluster in the Tambopata region of Amazonian Peru. The net present value of ecotourism-controlled land is given by the producer surplus (profits plus fixed costs of ecotourism lodges): US$ 1,158 ha(-1), which is higher than all currently practiced alternatives, including unsustainable logging, ranching, and agriculture. To our knowledge, this is the first sector-wide study of profitability and producer surplus in a developing-country ecotourism sector and the first to compare against equivalent measures for a spectrum of alternative uses. We also find that ecotourism-controlled land sequesters between 5.3 to 8.7 million tons of above-ground carbon, which is equivalent to between 3000-5000 years of carbon emissions from the domestic component of air and surface travel between the gateway city of Cusco and the lodges, at 2005 emission rates. Ecotourism in Tambopata has successfully monetized the hedonic value of wild nature in Amazonian Peru, and justifies the maintenance of intact rainforest over all alternative uses on narrow economic grounds alone.

[Synergistic emission reduction of chief air pollutants and greenhouse gases-based on scenario simulations of energy consumptions in Beijing].

PubMed

Xie, Yuan-bo; Li, Wei

2013-05-01

It is one of the common targets and important tasks for energy management and environmental control of Beijing to improve urban air quality while reducing the emissions of greenhouse gases (GHG). Here, based on the interim and long term developmental planning and energy structure of the city, three energy consumption scenarios in low, moderate and high restrictions were designed by taking the potential energy saving policies and environmental targets into account. The long-range energy alternatives planning (LEAP) model was employed to predict and evaluate reduction effects of the chief air pollutants and GHG during 2010 to 2020 under the three given scenarios. The results showed that if urban energy consumption system was optimized or adjusted by exercising energy saving and emission reduction and pollution control measures, the predicted energy uses will be reduced by 10 to 30 million tons of coal equivalents by 2020. Under the two energy scenarios with moderate and high restrictions, the anticipated emissions of SO2, NOx, PM10, PM2.5, VOC and GHG will be respectively reduced to 71 to 100.2, 159.2 to 218.7, 89.8 to 133.8, 51.4 to 96.0, 56.4 to 74.8 and 148 200 to 164 700 thousand tons. Correspondingly, when compared with the low-restriction scenario, the reducing rate will be 53% to 67% , 50% to 64% , 33% to 55% , 25% to 60% , 41% to 55% and 26% to 34% respectively. Furthermore, based on a study of synergistic emission reduction of the air pollutants and GHG, it was proposed that the adjustment and control of energy consumptions shall be intensively developed in the three sectors of industry, transportation and services. In this way the synergistic reduction of the emissions of chief air pollutants and GHG will be achieved; meanwhile the pressures of energy demands may be deliberately relieved.

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.

NITROUS OXIDE EMISSIONS FROM SOUTHERN HIGH PLAINS BEEF CATTLE FEEDYARDS: MEASUREMENT AND MODELING

USDA-ARS?s Scientific Manuscript database

Predictive models for nitrous oxide emission are crucial for assessing the greenhouse gas footprint of beef cattle production. The Texas Panhandle produces approximately 42% of finished beef in the U.S. and cattle production is estimated to contribute 8 Tg carbon dioxide equivalents from nitrous oxi...

47 CFR 5.61 - Procedure for obtaining a special temporary authorization.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Office of Engineering and Technology Web site https://gullfoss2.fcc.gov/prod/oet/cf/els/index.cfm...) Frequency(ies) desired. (9) Maximum effective radiated power (ERP) or equivalent isotrophically radiated power (EIRP). (10) Emission designator (see § 2.201 of this chapter) or describe emission (bandwidth...

Step 2: Enter Baseline Energy Consumption Data | Climate Action Planning

Science.gov Websites

Scope 1: Emissions (Direct Combustion) T CO2e = Tonnes of Carbon Dioxide Equivalent* Gas (T CO2e) Oil (T CO2e) Coal (T CO2e) Fleet (T CO2e) Total (T CO2e) *Metric tons of CO2 equivalent or 2.204 lbs of CO2

40 CFR Table 5 to Subpart Mmmm of... - Model Rule-Toxic Equivalency Factors

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Model Rule-Toxic Equivalency Factors 5 Table 5 to Subpart MMMM of Part 60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Existing Sewage Sludge...

40 CFR Table 5 to Subpart Mmmm of... - Model Rule-Toxic Equivalency Factors

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Model Rule-Toxic Equivalency Factors 5 Table 5 to Subpart MMMM of Part 60 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Emission Guidelines and Compliance Times for Existing Sewage Sludge...

Mitigation potential of soil carbon management overestimated by neglecting N2O emissions

NASA Astrophysics Data System (ADS)

Lugato, Emanuele; Leip, Adrian; Jones, Arwyn

2018-03-01

International initiatives such as the `4 per 1000' are promoting enhanced carbon (C) sequestration in agricultural soils as a way to mitigate greenhouse gas emissions1. However, changes in soil organic C turnover feed back into the nitrogen (N) cycle2, meaning that variation in soil nitrous oxide (N2O) emissions may offset or enhance C sequestration actions3. Here we use a biogeochemistry model on approximately 8,000 soil sampling locations in the European Union4 to quantify the net CO2 equivalent (CO2e) fluxes associated with representative C-mitigating agricultural practices. Practices based on integrated crop residue retention and lower soil disturbance are found to not increase N2O emissions as long as C accumulation continues (until around 2040), thereafter leading to a moderate C sequestration offset mostly below 47% by 2100. The introduction of N-fixing cover crops allowed higher C accumulation over the initial 20 years, but this gain was progressively offset by higher N2O emissions over time. By 2060, around half of the sites became a net source of greenhouse gases. We conclude that significant CO2 mitigation can be achieved in the initial 20-30 years of any C management scheme, but after that N inputs should be controlled through appropriate management.

Development of a dedicated ethanol ultra-low emission vehicle (ULEV): Final report

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

Dodge, L.; Bourn, G.; Callahan, T.

The objective of this project was to develop a commercially competitive vehicle powered by ethanol (or an ethanol blend) that can meet California`s ultra-low emission vehicle (ULEV) standards and equivalent corporate average fuel economy (CAFE) energy efficiency for a light-duty passenger car application. The definition of commercially competitive is independent of fuel cost, but does include technical requirements for competitive power, performance, refueling times, vehicle range, driveability, fuel handling safety, and overall emissions performance. This report summarizes the fourth and final phase of this project, and also the overall project. The focus of this report is the technology used tomore » develop a dedicated ethanol-fueled ULEV, and the emissions results documenting ULV performance. Some of the details for the control system and hardware changes are presented in two appendices that are SAE papers. The demonstrator vehicle has a number of advanced technological features, but it is currently configured with standard original equipment manufacturer (OEM) under-engine catalysts. Close-coupled catalysts would improve emissions results further, but no close-coupled catalysts were available for this testing. Recently, close-coupled catalysts were obtained, but installation and testing will be performed in the future. This report also briefly summarizes work in several other related areas that supported the demonstrator vehicle work.« less

U.S. Light-duty Vehicle Air Conditioning Fuel Use and the Impact of Four Solar/Thermal Control Technologies

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

Rugh, John P; Kekelia, Bidzina; Kreutzer, Cory J

The U.S. uses 7.6 billion gallons of fuel per year for vehicle air conditioning (A/C), equivalent to 5.7 percent of the total national light-duty vehicle (LDV) fuel use. This equates to 30 gallons/year per vehicle, or 23.5 grams (g) of carbon dioxide (CO2) per mile, for an average U.S. vehicle. A/C is a significant contribution to national fuel use; therefore, technologies that reduce A/C loads may reduce operational costs, A/C fuel use, and CO2 emissions. Since A/C is not operated during standard EPA fuel economy testing protocols, EPA provides off-cycle credits to encourage OEMs to implement advanced A/C technologies thatmore » reduce fuel use in the real world. NREL researchers assessed thermal/solar off-cycle credits available in the U.S. Environmental Protection Agency's (EPA's) Final Rule for Model Year 2017 and Later Light-Duty Vehicle Greenhouse Gas Emissions and Corporate Average Fuel Economy. Credits include glazings, solar reflective paint, and passive and active cabin ventilation. Implementing solar control glass reduced CO2 emissions by 2.0 g/mi, and solar reflective paint resulted in a reduction of 0.8 g/mi. Active and passive ventilation strategies only reduced emissions by 0.1 and 0.2 g/mi, respectively. The national-level analysis process is powerful and general; it can be used to determine the impact of a wide range of new vehicle thermal technologies on fuel use, EV range, and CO2 emissions.« less

Estimated HCFC-22 emissions for 1990-2050 in China and the increasing contribution to global emissions

NASA Astrophysics Data System (ADS)

Li, Zhifang; Bie, Pengju; Wang, Ziyuan; Zhang, Zhaoyang; Jiang, Hanyu; Xu, Weiguang; Zhang, Jianbo; Hu, Jianxin

2016-05-01

Chlorodifluoromethane (CHClF2, HCFC-22) is a widely used refrigerant and foaming agent that is not only an ozone-depleting substance (ozone depletion potential (ODP), 0.04) but also a greenhouse gas (global warming potential (GWP), 1780). A comprehensive historical emission inventory for 1990-2014 was produced using a bottom-up method, and a projection through to 2050 was made for China. The results demonstrated that historical emissions increased sharply from 0.2 Gg/yr in 1990 to 127.2 Gg/yr in 2014. Room air-conditioners (RACs), industrial and commercial refrigeration (ICR), and extruded polystyrene (XPS) were three primary emission sources, and accounted for an average of 95.4% of the total emissions over the period studied. The percentage of global HCFC-22 emissions originating from China significantly increased from 0.1% in 1990 to 31.6% in 2012, with an average growth rate of 1.4% per year. Under the Montreal Protocol phasing-out (MPPO) scenario, future emissions were expected to reach a peak of 133.5 Gg/yr in 2016 and then continuously decline to 10.2 Gg/yr in 2050. The accumulative reduction for 2015-2050 would be 5533.8 Gg (equivalent to 221.4 CFC-11-eq Gg and 9850.1 CO2-eq Tg), which is approximately equivalent to the total CO2 emission for China in 2012 (9900 Tg) (Olivier et al., 2013), compared with the no Montreal Protocol scenario (NMP). Under the MPPO scenario, two cases were analyzed to explore the future emission ranges in China. A comparison between the two cases implied that the choice of emission reduction policy will have a considerable impact on HCFC-22 emissions.

Leachate treatment in landfills is a significant N2O source.

PubMed

Wang, Xiaojun; Jia, Mingsheng; Zhang, Chengliang; Chen, Shaohua; Cai, Zucong

2017-10-15

The importance of methane (CH 4 ) emissions from landfills has been extensively documented, while the nitrous oxide (N 2 O) emissions from landfills are considered negligible. In this study, three landfills were selected to measure CH 4 and N 2 O emissions using the static chamber method. Dongbu (DB) and Dongfu (DF) landfills, both located in Xiamen city, Fujian Province, were classified as sanitary. The former started to receive solid waste from Xiamen city in 2009, and the latter was closed in 2009. Nanjing (NJ) landfill, located in Nanjing county, Fujian Province, was classified as managed. Results showed that for the landfill reservoirs, CH 4 emissions were significant, while N 2 O emissions occurred mainly in operating areas (on average, 16.3 and 19.0mgN 2 Om -2 h -1 for DB and NJ landfills, respectively) and made a negligible contribution to the total greenhouse gas emissions in term of CO 2 equivalent. However, significant N 2 O emissions were observed in the leachate treatment systems of sanitary landfills and contributed 72.8% and 45.6% of total emissions in term of CO 2 equivalent in DB and DF landfills, respectively. The N 2 O emission factor (EF) of the leachate treatment systems was in the range of 8.9-11.9% of the removed nitrogen. The total N 2 O emissions from the leachate treatment systems of landfills in Xiamen city were estimated to be as high as 8.55gN 2 O-Ncapita -1 yr -1 . These results indicated that N 2 O emissions from leachate treatment systems of sanitary landfills were not negligible and should be included in national and/or local inventories of greenhouse gas emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of feeding strategies and cropping systems on greenhouse gas emission from Wisconsin certified organic dairy farms.

PubMed

Liang, D; Sun, F; Wattiaux, M A; Cabrera, V E; Hedtcke, J L; Silva, E M

2017-07-01

Organic agriculture continues to expand in the United States, both in total hectares and market share. However, management practices used by dairy organic producers, and their resulting environmental impacts, vary across farms. This study used a partial life cycle assessment approach to estimate the effect of different feeding strategies and associated crop production on greenhouse gas emissions (GHG) from Wisconsin certified organic dairy farms. Field and livestock-driven emissions were calculated using 2 data sets. One was a 20-yr data set from the Wisconsin Integrated Cropping System Trial documenting management inputs, crop and pasture yields, and soil characteristics, used to estimate field-level emissions from land associated with feed production (row crop and pasture), including N 2 O and soil carbon sequestration. The other was a data set summarizing organic farm management in Wisconsin, which was used to estimate replacement heifer emission (CO 2 equivalents), enteric methane (CH 4 ), and manure management (N 2 O and CH 4 ). Three combinations of corn grain (CG) and soybean (SB) as concentrate (all corn = 100% CG; baseline = 75% CG + 25% SB; half corn = 50% CG + 50% SB) were assigned to each of 4 representative management strategies as determined by survey data. Overall, GHG emissions associated with crop production was 1,297 ± 136 kg of CO 2 equivalents/t of ECM without accounting for soil carbon changes (ΔSC), and GHG emission with ΔSC was 1,457 ± 111 kg of CO 2 equivalents/t of ECM, with greater reliance on pasture resulting in less ΔSC. Higher levels of milk production were a major driver associated with reduction in GHG emission per metric tonne of ECM. Emissions per metric tonne of ECM increased with increasing proportion of SB in the ration; however, including SB in the crop rotation decreased N 2 O emission per metric tonne of ECM from cropland due to lower applications of organically approved N fertility inputs. More SB at the expense of CG in the ration reduced enteric CH 4 emission per metric tonne of ECM (because of greater dietary fat content) but increased N 2 O emission per metric tonne of ECM from manure (because of greater N content). An increased reliance on pasture for feed at the expense of grain resulted in decreased in milk production, subsequently leading to substantially higher emissions per metric tonne of ECM. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Detailed non-LTE calculations of the iron emission from NGC 1068

NASA Technical Reports Server (NTRS)

Band, David L.; Klein, Richard I.; Castor, John I.; Nash, J. K.

1989-01-01

The X-ray iron line emission from NGC 1068 observed by the Ginga satellite is modeled using the new multiline, multilevel, non-LTE radiative transport code ALTAIR and a detailed atomic model for Ne-like through stripped iron. The parameter space of the obscured type 1 Seyfert nucleus model for this object is studied. The equivalent width is greater than previously predicted. It is found that detailed radiative transfer can have a significant effect on the observed line flux both for the K alpha line and for the L-shell emission. The ionization of the iron increases with temperature. Therefore the K alpha equivalent width and energy is a function not only of the ionization parameter, but also of the column depth and temperature. For a likely model of NGC 1068 it is found that the iron abundance is about twice solar, but that modifications of this model may permit a smaller abundance.

Directional emission from dye-functionalized plasmonic DNA superlattice microcavities

PubMed Central

Park, Daniel J.; Ku, Jessie C.; Sun, Lin; Lethiec, Clotilde M.; Stern, Nathaniel P.; Schatz, George C.; Mirkin, Chad A.

2017-01-01

Three-dimensional plasmonic superlattice microcavities, made from programmable atom equivalents comprising gold nanoparticles functionalized with DNA, are used as a testbed to study directional light emission. DNA-guided nanoparticle colloidal crystallization allows for the formation of micrometer-scale single-crystal body-centered cubic gold nanoparticle superlattices, with dye molecules coupled to the DNA strands that link the particles together, in the form of a rhombic dodecahedron. Encapsulation in silica allows one to create robust architectures with the plasmonically active particles and dye molecules fixed in space. At the micrometer scale, the anisotropic rhombic dodecahedron crystal habit couples with photonic modes to give directional light emission. At the nanoscale, the interaction between the dye dipoles and surface plasmons can be finely tuned by coupling the dye molecules to specific sites of the DNA particle-linker strands, thereby modulating dye–nanoparticle distance (three different positions are studied). The ability to control dye position with subnanometer precision allows one to systematically tune plasmon–excition interaction strength and decay lifetime, the results of which have been supported by electrodynamics calculations that span length scales from nanometers to micrometers. The unique ability to control surface plasmon/exciton interactions within such superlattice microcavities will catalyze studies involving quantum optics, plasmon laser physics, strong coupling, and nonlinear phenomena. PMID:28053232

Effect of irrigation, nitrogen application, and a nitrification inhibitor on nitrous oxide, carbon dioxide and methane emissions from an olive (Olea europaea L.) orchard.

PubMed

Maris, S C; Teira-Esmatges, M R; Arbonés, A; Rufat, J

2015-12-15

Drip irrigation combined with nitrogen (N) fertigation is applied in order to save water and improve nutrient efficiency. Nitrification inhibitors reduce greenhouse gas emissions. A field study was conducted to compare the emissions of nitrous oxide (N2O), carbon dioxide (CO2) and methane (CH4) associated with the application of N fertiliser through fertigation (0 and 50kgNha(-1)), and 50kgNha(-1)+nitrification inhibitor in a high tree density Arbequina olive orchard. Spanish Arbequina is the most suited variety for super intensive olive groves. This system allows reducing production costs and increases crop yield. Moreover its oil has excellent sensorial features. Subsurface drip irrigation markedly reduced N2O and N2O+N2 emissions compared with surface drip irrigation. Fertiliser application significantly increased N2O+N2, but not N2O emissions. Denitrification was the main source of N2O. The N2O losses (calculated as emission factor) ranging from -0.03 to 0.14% of the N applied, were lower than the IPCC (2007) values. The N2O+N2 losses were the largest, equivalent to 1.80% of the N applied, from the 50kgNha(-1)+drip irrigation treatment which resulted in water filled pore space >60% most of the time (high moisture). Nitrogen fertilisation significantly reduced CO2 emissions in 2011, but only for the subsurface drip irrigation strategies in 2012. The olive orchard acted as a net CH4 sink for all the treatments. Applying a nitrification inhibitor (DMPP), the cumulative N2O and N2O+N2 emissions were significantly reduced with respect to the control. The DMPP also inhibited CO2 emissions and significantly increased CH4 oxidation. Considering global warming potential, greenhouse gas intensity, cumulative N2O emissions and oil production, it can be concluded that applying DMPP with 50kgNha(-1)+drip irrigation treatment was the best option combining productivity with keeping greenhouse gas emissions under control. Copyright © 2015 Elsevier B.V. All rights reserved.

Reduced prefrontal and increased subcortical brain functioning assessed using positron emission tomography in predatory and affective murderers.

PubMed

Raine, A; Meloy, J R; Bihrle, S; Stoddard, J; LaCasse, L; Buchsbaum, M S

1998-01-01

There appear to be no brain imaging studies investigating which brain mechanisms subserve affective, impulsive violence versus planned, predatory violence. It was hypothesized that affectively violent offenders would have lower prefrontal activity, higher subcortical activity, and reduced prefrontal/subcortical ratios relative to controls, while predatory violent offenders would show relatively normal brain functioning. Glucose metabolism was assessed using positron emission tomography in 41 comparisons, 15 predatory murderers, and nine affective murderers in left and right hemisphere prefrontal (medial and lateral) and subcortical (amygdala, midbrain, hippocampus, and thalamus) regions. Affective murderers relative to comparisons had lower left and right prefrontal functioning, higher right hemisphere subcortical functioning, and lower right hemisphere prefrontal/subcortical ratios. In contrast, predatory murderers had prefrontal functioning that was more equivalent to comparisons, while also having excessively high right subcortical activity. Results support the hypothesis that emotional, unplanned impulsive murderers are less able to regulate and control aggressive impulses generated from subcortical structures due to deficient prefrontal regulation. It is hypothesized that excessive subcortical activity predisposes to aggressive behaviour, but that while predatory murderers have sufficiently good prefrontal functioning to regulate these aggressive impulses, the affective murderers lack such prefrontal control over emotion regulation.

Reinforcement-learning-based output-feedback control of nonstrict nonlinear discrete-time systems with application to engine emission control.

PubMed

Shih, Peter; Kaul, Brian C; Jagannathan, Sarangapani; Drallmeier, James A

2009-10-01

A novel reinforcement-learning-based output adaptive neural network (NN) controller, which is also referred to as the adaptive-critic NN controller, is developed to deliver the desired tracking performance for a class of nonlinear discrete-time systems expressed in nonstrict feedback form in the presence of bounded and unknown disturbances. The adaptive-critic NN controller consists of an observer, a critic, and two action NNs. The observer estimates the states and output, and the two action NNs provide virtual and actual control inputs to the nonlinear discrete-time system. The critic approximates a certain strategic utility function, and the action NNs minimize the strategic utility function and control inputs. All NN weights adapt online toward minimization of a performance index, utilizing the gradient-descent-based rule, in contrast with iteration-based adaptive-critic schemes. Lyapunov functions are used to show the stability of the closed-loop tracking error, weights, and observer estimates. Separation and certainty equivalence principles, persistency of excitation condition, and linearity in the unknown parameter assumption are not needed. Experimental results on a spark ignition (SI) engine operating lean at an equivalence ratio of 0.75 show a significant (25%) reduction in cyclic dispersion in heat release with control, while the average fuel input changes by less than 1% compared with the uncontrolled case. Consequently, oxides of nitrogen (NO(x)) drop by 30%, and unburned hydrocarbons drop by 16% with control. Overall, NO(x)'s are reduced by over 80% compared with stoichiometric levels.

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

NONE

The Voluntary Reporting of Greenhouse Gases Program, required by Section 1605(b) of the Energy Policy Act of 1992, records the results of voluntary measures to reduce, avoid, or sequester greenhouse gas emissions. In 1998, 156 US companies and other organizations reported to the Energy information Administration that, during 1997, they had achieved greenhouse gas emission reductions and carbon sequestration equivalent to 166 million tons of carbon dioxide, or about 2.5% of total US emissions for the year. For the 1,229 emission reduction projects reported, reductions usually were measured by comparing an estimate of actual emissions with an estimate of whatmore » emissions would have been had the project not been implemented.« less

Experimental investigation of aerodynamics, combustion, and emissions characteristics within the primary zone of a gas turbine combustor

NASA Astrophysics Data System (ADS)

Elkady, Ahmed M.

2006-04-01

The present work investigates pollutant emissions production, mainly nitric oxides and carbon monoxide, within the primary zone of a highly swirling combustion and methods with which to reduce their formation. A baseline study was executed at different equivalence ratios and different inlet air temperatures. The study was then extended to investigate the effects of utilizing transverse air jets on pollutant emission characteristics at different jet locations, jet mass ratio, and overall equivalence ratio as well as to investigate the jets' overall interactions with the recirculation zone. A Fourier Transform Infrared (FTIR) spectrometer was employed to measure emissions concentrations generated during combustion of Jet-A fuel in a swirl-cup assembly. Laser Doppler Velocimetry (LDV) was employed to investigate the mean flow aerodynamics within the combustor. Particle Image Velocimetry (PIV) was utilized to capture the instantaneous aerodynamic behavior of the non-reacting primary zone. Results illustrate that NOx production is a function of both the recirculation zone and the flame length. At low overall equivalence ratios, the recirculation zone is found to be the main producer of NOx. At near stoichiometric conditions, the post recirculation zone appears to be responsible for the majority of NOx produced. Results reveal the possibility of injecting air into the recirculation zone without altering flame stability to improve emission characteristics. Depending on the jet location and strength, nitric oxides as well as carbon monoxide can be reduced simultaneously. Placing the primary air jet just downstream of the fuel rich recirculation zone can lead to a significant reduction in both nitric oxides and carbon monoxide. In the case of fuel lean recirculation zone, reduction of nitric oxides can occur by placing the jets below the location of maximum radius of the recirculation zone.

Numerical modeling of NO formation in laminar Bunsen flames -- A flamelet approach

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

Chou, C.P.; Chen, J.Y.; Yam, C.G.

1998-08-01

Based on the flamelet concept, a numerical model has been developed for fast predictions of NO{sub x} and CO emissions from laminar flames. The model is applied to studying NO formation in the secondary nonpremixed flame zone of fuel-rich methane Bunsen flames. By solving the steady-state flamelet equations with the detailed GR12.1 methane-air mechanism, a flamelet library is generated containing thermochemical information for a range of scalar dissipation rates at the ambient pressure condition. Modeling of NO formation is made by solving its conservation equation with chemical source term evaluated based on flamelet library using the extended Zeldovich mechanism andmore » NO reburning reactions. The optically-thin radiation heat transfer model is used to explore the potential effect of heat loss on thermal NO formation. The numerical scheme solves the two-dimensional Navier-Stokes equations as well as three additional equations: the mixture fraction, the NO mass fraction, and the enthalpy deficit due to radiative heat loss. With an established flamelet library, typical computing times are about 5 hours per calculation on a DEC-3000 300LX workstation. The predicted mixing field, radial temperature profiles, and NO distributions compare favorably with recent experimental data obtained by Nguyen et al. The dependence of NO{sub x} emission on equivalence ratio is studied numerically and the predictions are found to agree reasonably well with the measurements by Muss. The computed results show a decreasing trend of NO{sub x} emission with the equivalence ratio but an increasing trend in the CO emission index. By examining this trade-off between NO{sub x} and CO, an optimal equivalence ratio of 1.4 is found to yield the lowest combined emission.« less

Economic and policy implications of the cumulative carbon budget

NASA Astrophysics Data System (ADS)

Allen, M. R.; Otto, F. E. L.; Otto, A.; Hepburn, C.

2014-12-01

The importance of cumulative carbon emissions in determining long-term risks of climate change presents considerable challenges to policy makers. The traditional notion of "total CO2-equivalent emissions", which forms the backbone of agreements such as the Kyoto Protocol and the European Emissions Trading System, is fundamentally flawed. Measures to reduce short-lived climate pollutants benefit the current generation, while measures to reduce long-lived climate pollutants benefit future generations, so there is no sense in which they can ever be considered equivalent. Debates over the correct metric used to compute CO2-equivalence are thus entirely moot: both long-lived and short-lived emissions will need to be addressed if all generations are to be protected from dangerous climate change. As far as long-lived climate pollutants are concerned, the latest IPCC report highlights the overwhelming importance of carbon capture and storage in determining the cost of meeting the goal of limiting anthropogenic warming to two degrees. We will show that this importance arises directly from the cumulative carbon budget and the role of CCS as the technology of last resort before economic activity needs to be restricted to meet ambitious climate targets. It highlights the need to increase the rate of CCS deployment by orders of magnitude if the option of avoiding two degrees is to be retained. The difficulty of achieving this speed of deployment through conventional incentives and carbon-pricing mechanisms suggests a need for a much more direct mandatory approach. Despite their theoretical economic inefficiency, the success of recent regulatory measures in achieving greenhouse gas emissions reductions in jurisdictions such as the United States suggests an extension of the regulatory approach could be a more effective and politically acceptable means of achieving adequately rapid CCS deployment than conventional carbon taxes or cap-and-trade systems.

High-Resolution Spectroscopy of [Ne II] Emission from AA Tau and GM Aur

NASA Astrophysics Data System (ADS)

Najita, Joan R.; Doppmann, Greg W.; Bitner, Martin A.; Richter, Matthew J.; Lacy, John H.; Jaffe, Daniel T.; Carr, John S.; Meijerink, Rowin; Blake, Geoffrey A.; Herczeg, Gregory J.; Glassgold, Alfred E.

2009-05-01

We present high-resolution (R = 80,000) spectroscopy of [Ne II] emission from two young stars, GM Aur and AA Tau, which have moderate to high inclinations. The emission from both sources appears centered near the stellar velocity and is broader than the [Ne II] emission measured previously for the face-on disk system TW Hya. These properties are consistent with a disk origin for the [Ne II] emission we detect, with disk rotation (rather than photoevaporation or turbulence in a hot disk atmosphere) playing the dominant role in the origin of the line width. In the non-face-on systems, the [Ne II] emission is narrower than the CO fundamental emission from the same sources. If the widths of both diagnostics are dominated by Keplerian rotation, this suggests that the [Ne II] emission arises from larger disk radii on average than does the CO emission. The equivalent width of the [Ne II] emission we detect is less than that of the spectrally unresolved [Ne II] feature in the Spitzer spectra of the same sources. Variability in the [Ne II] emission or the mid-infrared continuum, a spatially extended [Ne II] component, or a very (spectrally) broad [Ne II] component might account for the difference in the equivalent widths. Based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the Science and Technology Facilities Council (United Kingdom), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Ministrio da Cincia e Tecnologia (Brazil), and SECYT (Argentina).

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials.

PubMed

Subaiya, Saleena; Hogg, Euan; Roberts, Ian

2011-02-03

All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. CRASH-1: ISRCTN74459797CRASH-2: ISRCTN86750102.

Comparison of physically- and economically-based CO2-equivalences for methane

NASA Astrophysics Data System (ADS)

Boucher, O.

2012-01-01

There is a controversy on the role methane (and other short-lived species) should play in climate mitigation policies and no consensus on what an optimal methane CO2-equivalence should be. We revisit this question by discussing the relative merits of physically-based (i.e. Global Warming Potential or GWP and Global Temperature change Potential or GTP) and socio-economically-based climate metrics. To this effect we use a simplified Global Damage Potential (GDP) that was introduced by earlier authors and investigate the uncertainties in the methane CO2-equivalence that arise from physical and socio-economic factors. The median value of the methane GDP comes out very close to the widely used methane 100-year GWP because of various compensating effects. However there is a large spread in possible methane CO2-equivalences (1-99% interval: 10.0-42.5; 5-95% interval: 12.5-38.0) that is essentially due to the choice in some socio-economic parameters (i.e. the damage cost function and the discount rate). The methane 100-year GTP falls outside these ranges. It is legitimate to increase the methane CO2-equivalence in the future as global warming unfolds. While changes in biogeochemical cycles and radiative efficiencies cause some small changes to physically-based metrics, a systematic increase in the methane CO2-equivalence can only be achieved by some ad-hoc shortening of the time horizon. In contrast using a convex damage cost function provides a natural increase in the methane CO2-equivalence for the socio-economically-based metrics. We also show that a methane CO2-equivalence based on a pulse emission is sufficient to inform multi-year climate policies and emissions reductions as long as there is some degree of visibility on CO2 prices and CO2-equivalences.

Sensitivity of Inverse Estimation of 2004 Elemental Carbon Emissions Inventory in the United States to the Choice of Observational Networks

EPA Science Inventory

Choice of observational networks used for inverse re-estimation of elemental (or black) carbon (EC) emissions in the United States impacts results. We convert the Thermal Optical Transmittance (TOT) EC measurements to the Thermal Optical Reflectance (TOR) equivalent to make full...

40 CFR 1042.101 - Exhaust emission standards for Category 1 engines and Category 2 engines.

Code of Federal Regulations, 2013 CFR

2013-07-01

... information equivalent to such in-use data, such as data from research engines or similar engine models that... Category 1 engines and Category 2 engines. 1042.101 Section 1042.101 Protection of Environment... MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.101...

40 CFR 1042.101 - Exhaust emission standards for Category 1 engines and Category 2 engines.

Code of Federal Regulations, 2012 CFR

2012-07-01

... information equivalent to such in-use data, such as data from research engines or similar engine models that... Category 1 engines and Category 2 engines. 1042.101 Section 1042.101 Protection of Environment... MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.101...

40 CFR 1042.101 - Exhaust emission standards for Category 1 engines and Category 2 engines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... information equivalent to such in-use data, such as data from research engines or similar engine models that... Category 1 engines and Category 2 engines. 1042.101 Section 1042.101 Protection of Environment... MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.101...

40 CFR 86.410-90 - Emission standards for 1990 and later model year motorcycles.

Code of Federal Regulations, 2010 CFR

2010-07-01

... petroleum gas-fueled motorcycles): (i) Hydrocarbons. 5.0 grams per vehicle kilometer. (ii) Carbon monoxide. 12 grams per vehicle kilometer. (2) Exhaust emissions from 1990 and later model year methanol-fueled motorcycles shall not exceed: (i) Total hydrocarbon equivalent. 5.0 grams per vehicle kilometer. (ii) Carbon...

40 CFR 86.410-90 - Emission standards for 1990 and later model year motorcycles.

Code of Federal Regulations, 2013 CFR

2013-07-01

... petroleum gas-fueled motorcycles): (i) Hydrocarbons. 5.0 grams per vehicle kilometer. (ii) Carbon monoxide. 12 grams per vehicle kilometer. (2) Exhaust emissions from 1990 and later model year methanol-fueled motorcycles shall not exceed: (i) Total hydrocarbon equivalent. 5.0 grams per vehicle kilometer. (ii) Carbon...

40 CFR 86.410-90 - Emission standards for 1990 and later model year motorcycles.

Code of Federal Regulations, 2012 CFR

2012-07-01

... petroleum gas-fueled motorcycles): (i) Hydrocarbons. 5.0 grams per vehicle kilometer. (ii) Carbon monoxide. 12 grams per vehicle kilometer. (2) Exhaust emissions from 1990 and later model year methanol-fueled motorcycles shall not exceed: (i) Total hydrocarbon equivalent. 5.0 grams per vehicle kilometer. (ii) Carbon...

40 CFR 86.410-90 - Emission standards for 1990 and later model year motorcycles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... petroleum gas-fueled motorcycles): (i) Hydrocarbons. 5.0 grams per vehicle kilometer. (ii) Carbon monoxide. 12 grams per vehicle kilometer. (2) Exhaust emissions from 1990 and later model year methanol-fueled motorcycles shall not exceed: (i) Total hydrocarbon equivalent. 5.0 grams per vehicle kilometer. (ii) Carbon...

40 CFR 86.410-90 - Emission standards for 1990 and later model year motorcycles.

Code of Federal Regulations, 2011 CFR

2011-07-01

... petroleum gas-fueled motorcycles): (i) Hydrocarbons. 5.0 grams per vehicle kilometer. (ii) Carbon monoxide. 12 grams per vehicle kilometer. (2) Exhaust emissions from 1990 and later model year methanol-fueled motorcycles shall not exceed: (i) Total hydrocarbon equivalent. 5.0 grams per vehicle kilometer. (ii) Carbon...

40 CFR Appendix IV to Part 92 - Guidelines for Determining Equivalency Between Emission Measurement Systems

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emission Measurement Systems This appendix describes a series of correlation criteria that EPA considers to... results from each system. (b) Correlation criteria for particulate measurements. (1) The correlation... system (i.e., avgalt/avgspc) should be between 0.97 and 1.05. (c) Correlation criteria for other...

40 CFR Appendix IV to Part 92 - Guidelines for Determining Equivalency Between Emission Measurement Systems

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emission Measurement Systems This appendix describes a series of correlation criteria that EPA considers to... results from each system. (b) Correlation criteria for particulate measurements. (1) The correlation... system (i.e., avgalt/avgspc) should be between 0.97 and 1.05. (c) Correlation criteria for other...

Modeling and Simulation of a Free-Piston Engine with Electrical Generator Using HCCI Combustion

NASA Astrophysics Data System (ADS)

Alrbai, Mohammad

Free-piston engines have the potential to challenge the conventional crankshaft engines by their design simplicity and higher operational efficiency. Many studies have been performed to overcome the limitations of the free-piston devices especially the stability and control issues. The investigations within the presented dissertation aim to satisfy many objectives by employing the approach of chemical kinetics to present the combustion process in the free-piston engine. This approach in addition to its advanced accuracy over the empirical methods, it has many other features like the ability to analyze the engine emissions. The effect of the heat release rate (HRR) on the engine performance is considered as the main objective. Understanding the relation between the HRR and the piston dynamics helps in enhancing the system efficiency and identifying the parameters that affect the overall performance. The dissertation covers some other objectives that belongs to the combustion phasing. Exhaust gas recirculation (EGR), equivalence ratio and the intake temperature represent the main combustion parameters, which have been discussed in this dissertation. To obtain the stability in system performance, the model requires a proper controller to simulate the operation and manage the different system parameters; for this purpose, different controlling techniques have been employed. In addition, the dissertation considers some other topics like engine emissions, fuels and fuels mechanisms. The model of the study describes the processes within a single cylinder, two stroke engine, which includes springs to support higher frequencies, reduce cyclic variations and sustain the engine compression ratio. An electrical generator presents the engine load; the generator supports different load profiles and play the key role in controlling the system. The 1st law of thermodynamics and Newton's 2nd law are applied to couple the piston dynamics with the engine thermodynamics. The model governing equations represent a single zone perfectly stirred reactor (PSR) which contain a perfect mixing ideal gas mixture. The chemical kinetics approach is applied using Cantera/ MATLABRTM toolbox, which presents the combustion process. In this research, a homogenous charge compression ignition (HCCI) at different operational conditions is used. HCCI engines have high efficiencies and low emissions and can work within a wide range of fuels. The results have been presented in a multi-cycle simulation and a parametric study forms. In the case of the multi-cycle simulation, a 100 cycles of the engine operation have been simulated. The overall work that is delivered to the electrical generator presents 47% of the total fuel energy. The model indicates an average frequency of 125 Hz along the operational cycles. In order to eliminate the cyclic variations and ensure a continuous operation, a proportional derivative (PD) controller has been employed. The controller adjusts the generator load in order to minimize the difference between the bottom dead center (BDC) locations along the operation cycles. The PD controller shows weakness in achieving the full steady state operation, for this purpose; a proportional integral (PI) controller has been implemented. The PI controller seeks to achieve a specific compression ratio. The results show that; the PI controller indicates unique behavior after 15 cycles of operation where the model ended to fluctuate between two compression ratios only. The complex relation between the thermodynamics and the dynamics of the engine is the greatest challenge in examining the effectiveness of the PI controller. In the parametric investigations, EGR examinations show that NOx emission is reduced to less than the half, as 30 % of EGR is used; this occurs due to the EGR thermal and dilution effects, which cause significant drop in the peak bulk temperature and CO emissions as well. Under the applied conditions, EGR has the ability to raise the work output ratio by increasing the engine compression ratio. The examination of the EGR temperature on the engine performance indicates that cooled EGR charges have the advantage over the hot EGR mixtures on enhancing the work output ratio. At the same time, EGR temperature affects the NOx formation by speeding its instantaneous reactions rate. The dissertation includes a study of the effect of the intake temperature and the equivalence ratio (φ) as well. The increasing in the intake temperature reduce the time needed for ignition, but leads to a reduction in the work output ratio at the same time. Such results can help in studying high knock resistance fuels where ignition delay is a matter. In the case of the equivalence ratio, lean mixtures show efficiencies that exceed 50% compared to those at the stoichiometric conditions. In the case of the ultra-lean (φ<0.5) combustion, the results show that the NOx emission is with the minimal levels as well as the CO and the unburned hydrocarbons (UHC) emissions. Sensitivity analysis to the chemical kinetic mechanism for the fuel combustion has been presented also in the dissertation. Many mechanisms for different fuels have been investigated, for example; a modified mechanism for Methane that includes 36 species and 222 reactions has been compared with the full GRI 3.0 mechanism (53 species and 325 reactions). The results of this comparison indicate that the modified mechanism has the potential to replace the full one in some cases like in demonstrating the engine operation, but not in the engine emissions analysis.

Carbon dioxide emission implications if hydrofluorocarbons are regulated: a refrigeration case study.

PubMed

Blowers, Paul; Lownsbury, James M

2010-03-01

The U.S. is strongly considering regulating hydrofluorocarbons (HFCs) due to their global climate change forcing effects. A drop-in replacement hydrofluoroether has been evaluated using a gate-to-grave life cycle assessment of greenhouse gas emissions for the trade-offs between direct and indirect carbon dioxide equivalent emissions compared to a current HFC and a historically used refrigerant. The results indicate current regulations being considered may increase global climate change.

Observation of microwave absorption and emission from incoherent electron tunneling through a normal-metal-insulator-superconductor junction.

PubMed

Masuda, Shumpei; Tan, Kuan Y; Partanen, Matti; Lake, Russell E; Govenius, Joonas; Silveri, Matti; Grabert, Hermann; Möttönen, Mikko

2018-03-02

We experimentally study nanoscale normal-metal-insulator-superconductor junctions coupled to a superconducting microwave resonator. We observe that bias-voltage-controllable single-electron tunneling through the junctions gives rise to a direct conversion between the electrostatic energy and that of microwave photons. The measured power spectral density of the microwave radiation emitted by the resonator exceeds at high bias voltages that of an equivalent single-mode radiation source at 2.5 K although the phonon and electron reservoirs are at subkelvin temperatures. Measurements of the generated power quantitatively agree with a theoretical model in a wide range of bias voltages. Thus, we have developed a microwave source which is compatible with low-temperature electronics and offers convenient in-situ electrical control of the incoherent photon emission rate with a predetermined frequency, without relying on intrinsic voltage fluctuations of heated normal-metal components or suffering from unwanted losses in room temperature cables. Importantly, our observation of negative generated power at relatively low bias voltages provides a novel type of verification of the working principles of the recently discovered quantum-circuit refrigerator.

Environmental accounting--a decision support tool in WWTP operation and management.

PubMed

Clauson-Kaas, J; Poulsen, T S; Jacobsen, B N; Guildal, T; Wenzel, H

2001-01-01

The various emissions to water, air and soil from the municipal wastewater treatment plant of Avedore Wastewater Service Company are accounted for and quantified in terms of the environmental impacts to which they contribute: global warming, acidification, eutrophication, space demand for controlled deposition of residues, as well as persistent toxicity, human toxicity and eco-toxicity. The impacts are expressed on the same scale, namely as fraction of the total per capita loads in a national scenario 1990, also called the person equivalent or PE1990. This provides a compact and informative overview of the environmental impacts and allows for a holistic prioritisation in the operation and management of the plant. The accounting shows that the resulting emissions per person in the catchment area of the plant correspond to 0.5-5.0% of the average Danish PE1990 for the impacts in question.

Comparison of physically- and economically-based CO2-equivalences for methane

NASA Astrophysics Data System (ADS)

Boucher, O.

2012-05-01

There is a controversy on the role methane (and other short-lived species) should play in climate mitigation policies, and there is no consensus on what an optimal methane CO2-equivalence should be. We revisit this question by discussing some aspects of physically-based (i.e. global- warming potential or GWP and global temperature change potential or GTP) and socio-economically-based climate metrics. To this effect we use a simplified global damage potential (GDP) that was introduced by earlier authors and investigate the uncertainties in the methane CO2-equivalence that arise from physical and socio-economic factors. The median value of the methane GDP comes out very close to the widely used methane 100-yr GWP because of various compensating effects. However, there is a large spread in possible methane CO2-equivalences from this metric (1-99% interval: 10.0-42.5; 5-95% interval: 12.5-38.0) that is essentially due to the choice in some socio-economic parameters (i.e. the damage cost function and the discount rate). The main factor differentiating the methane 100-yr GTP from the methane 100-yr GWP and the GDP is the fact that the former metric is an end-point metric, whereas the latter are cumulative metrics. There is some rationale for an increase in the methane CO2-equivalence in the future as global warming unfolds, as implied by a convex damage function in the case of the GDP metric. We also show that a methane CO2-equivalence based on a pulse emission is sufficient to inform multi-year climate policies and emissions reductions, as long as there is enough visibility on CO2 prices and CO2-equivalences for the stakeholders.

Quantifying Terrestrial Ecosystem Carbon Stocks for Future GHG Mitigation, Sustainable Land-Use Planning and Adaptation to Climate Change in Quebec, Canada.

NASA Astrophysics Data System (ADS)

Garneau, M.; van Bellen, S.

2016-12-01

Based on various databases, carbon stocks of terrestrial ecosystems in the boreal and arctic biomes of Quebec were quantified as part of an evaluation of their capacity to mitigate anthropogenic greenhouse gas (GHG) emissions and estimate their vulnerability with respect to recent climate change and land use changes. The results of this project are contributing to the establishment of the Strategy for Climate Change Adaptation as well as the 2013-2020 Climate Change Action Plan of the Quebec Ministry of Environment, which aim to adapt the Quebec society to the effects of climate change and the reduction of GHG emissions. The total carbon stock of the soils of the forest and peatland ecosystems of Quebec was quantified at 18.00 Gt C or 66.0 Gt CO2-equivalent, of which 95% corresponds to the boreal and arctic regions. The mean carbon mass per unit area (kg C m-2) of peatlands is about nine times higher than that of forests, with values of 100,0 kg C m-2 for peatlands and 10,9 kg C m-2 for forest stands. In 2013, total anthropogenic emissions in Quebec were quantified at 82.6 Mt CO2-equivalent (Environment Canada, 2015), or 1.25‰ of the total Quebec ecosystem carbon stock. The total stock thus represents the equivalent of about 800 years of anthropogenic emissions at the current rate, divided between 478 years for peatlands and 321 years for forest soils. Future GHG mitigation policies and sustainable land-use planning should be supported by scientific data on terrestrial ecosystems carbon stocks. An increase in investments in peatland, wetland and forest conservation, management and rehabilitation may contribute to limit greenhouse gas emissions. It is therefore essential, that, following the objectives of multiple international organisations, the management of terrestrial carbon stocks becomes part of the national engagement to reduce GHG emissions.

Spatial variations in immediate greenhouse gases and aerosol emissions and resulting radiative forcing from wildfires in interior Alaska

USGS Publications Warehouse

Huang, Shengli; Liu, Heping; Dahal, Devendra; Jin, Suming; Li, Shuang; Liu, Shu-Guang

2016-01-01

Boreal fires can cool the climate; however, this conclusion came from individual fires and may not represent the whole story. We hypothesize that the climatic impact of boreal fires depends on local landscape heterogeneity such as burn severity, prefire vegetation type, and soil properties. To test this hypothesis, spatially explicit emission of greenhouse gases (GHGs) and aerosols and their resulting radiative forcing are required as an important and necessary component towards a full assessment. In this study, we integrated remote sensing (Landsat and MODIS) and models (carbon consumption model, emission factors model, and radiative forcing model) to calculate the carbon consumption, GHGs and aerosol emissions, and their radiative forcing of 2001–2010 fires at 30 m resolution in the Yukon River Basin of Alaska. Total carbon consumption showed significant spatial variation, with a mean of 2,615 g C m−2 and a standard deviation of 2,589 g C m−2. The carbon consumption led to different amounts of GHGs and aerosol emissions, ranging from 593.26 Tg (CO2) to 0.16 Tg (N2O). When converted to equivalent CO2 based on global warming potential metric, the maximum 20 years equivalent CO2 was black carbon (713.77 Tg), and the lowest 20 years equivalent CO2 was organic carbon (−583.13 Tg). The resulting radiative forcing also showed significant spatial variation: CO2, CH4, and N2O can cause a 20-year mean radiative forcing of 7.41 W m−2 with a standard deviation of 2.87 W m−2. This emission forcing heterogeneity indicates that different boreal fires have different climatic impacts. When considering the spatial variation of other forcings, such as surface shortwave forcing, we may conclude that some boreal fires, especially boreal deciduous fires, can warm the climate.

Comparing otoacoustic emissions evoked by chirp transients with constant absorbed sound power and constant incident pressure magnitude

PubMed Central

Keefe, Douglas H.; Feeney, M. Patrick; Hunter, Lisa L.; Fitzpatrick, Denis F.

2017-01-01

Human ear-canal properties of transient acoustic stimuli are contrasted that utilize measured ear-canal pressures in conjunction with measured acoustic pressure reflectance and admittance. These data are referenced to the tip of a probe snugly inserted into the ear canal. Promising procedures to calibrate across frequency include stimuli with controlled levels of incident pressure magnitude, absorbed sound power, and forward pressure magnitude. An equivalent pressure at the eardrum is calculated from these measured data using a transmission-line model of ear-canal acoustics parameterized by acoustically estimated ear-canal area at the probe tip and length between the probe tip and eardrum. Chirp stimuli with constant incident pressure magnitude and constant absorbed sound power across frequency were generated to elicit transient-evoked otoacoustic emissions (TEOAEs), which were measured in normal-hearing adult ears from 0.7 to 8 kHz. TEOAE stimuli had similar peak-to-peak equivalent sound pressure levels across calibration conditions. Frequency-domain TEOAEs were compared using signal level, signal-to-noise ratio (SNR), coherence synchrony modulus (CSM), group delay, and group spread. Time-domain TEOAEs were compared using SNR, CSM, instantaneous frequency and instantaneous bandwidth. Stimuli with constant incident pressure magnitude or constant absorbed sound power across frequency produce generally similar TEOAEs up to 8 kHz. PMID:28147608

Discharge processes and an electrical model of atmospheric pressure plasma jets in argon

NASA Astrophysics Data System (ADS)

Fang, Zhi; Shao, Tao; Yang, Jing; Zhang, Cheng

2016-01-01

In this paper, an atmospheric pressure plasma discharge in argon was generated using a needle-to-ring electrode configuration driven by a sinusoidal excitation voltage. The electric discharge processes and discharge characteristics were investigated by inspecting the voltage-current waveforms, Lissajous curves and lighting emission images. The change in discharge mode with applied voltage amplitude was studied and characterised, and three modes of corona discharge, dielectric barrier discharge (DBD) and jet discharge were identified, which appeared in turn with increasing applied voltage and can be distinguished clearly from the measured voltage-current waveforms, light-emission images and the changing gradient of discharge power with applied voltage. Based on the experimental results and discharge mechanism analysis, an equivalent electrical model and the corresponding equivalent circuit for characterising the whole discharge processes accurately was proposed, and the three discharge stages were characterised separately. A voltage-controlled current source (VCCS) associated with a resistance and a capacitance were used to represent the DBD stage, and the plasma plume and corona discharge were modelled by a variable capacitor in series with a variable resistor. Other factors that can influence the discharge, such as lead and stray capacitance values of the circuit, were also considered in the proposed model. Contribution to the Topical Issue "Recent Breakthroughs in Microplasma Science and Technology", edited by Kurt Becker, Jose Lopez, David Staack, Klaus-Dieter Weltmann and Wei Dong Zhu.

Evaluation of fuel-borne sodium effects on a DOC-DPF-SCR heavy-duty engine emission control system: Simulation of full-useful life

DOE PAGES

Lance, Michael J.; Wereszczak, Andrew A; Toops, Todd J.; ...

2016-10-17

Here we report that for renewable fuels to displace petroleum, they must be compatible with emissions control devices. Pure biodiesel contains up to 5 ppm Na + K and 5 ppm Ca + Mg metals, which have the potential to degrade diesel emissions control systems. This study aims to address these concerns, identify deactivation mechanisms, and determine if a lower limit is needed. Accelerated aging of a production exhaust system was conducted on an engine test stand over 1001 h using 20% biodiesel blended into ultra-low sulfur diesel (B20) doped with 14 ppm Na. This Na level is equivalent tomore » exposure to Na at the uppermost expected B100 value in a B20 blend for the system full-useful life. During the study, NOx emissions exceeded the engine certification limit of 0.33 g/bhp-hr before the 435,000-mile requirement. Replacing aged diesel oxidation catalyst (DOC), diesel particulate filter (DPF), and selective catalytic reduction (SCR) devices with new degreened parts showed that each device contributed equally to the NOx increase. Following this systems-based evaluation, a detailed investigation of the individual components was completed. Na was determined to have minimal impact on DOC activity. For this system, it is estimated that B20-Na resulted in 50% more ash into the DPF. However, the Na did not diffuse into the cordierite DPF nor degrade its mechanical properties. The SCR degradation was found to be caused by a small amount of precious group metals (PGM) contamination that increased NH3 oxidation, and lowered NOx reduction. Therefore, we determined that the primary effect of Na in this study is through increased ash in the DPF rather than deactivation of the catalytic activity.« less

Evaluation of fuel-borne sodium effects on a DOC-DPF-SCR heavy-duty engine emission control system: Simulation of full-useful life

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

Lance, Michael J.; Wereszczak, Andrew A; Toops, Todd J.

Here we report that for renewable fuels to displace petroleum, they must be compatible with emissions control devices. Pure biodiesel contains up to 5 ppm Na + K and 5 ppm Ca + Mg metals, which have the potential to degrade diesel emissions control systems. This study aims to address these concerns, identify deactivation mechanisms, and determine if a lower limit is needed. Accelerated aging of a production exhaust system was conducted on an engine test stand over 1001 h using 20% biodiesel blended into ultra-low sulfur diesel (B20) doped with 14 ppm Na. This Na level is equivalent tomore » exposure to Na at the uppermost expected B100 value in a B20 blend for the system full-useful life. During the study, NOx emissions exceeded the engine certification limit of 0.33 g/bhp-hr before the 435,000-mile requirement. Replacing aged diesel oxidation catalyst (DOC), diesel particulate filter (DPF), and selective catalytic reduction (SCR) devices with new degreened parts showed that each device contributed equally to the NOx increase. Following this systems-based evaluation, a detailed investigation of the individual components was completed. Na was determined to have minimal impact on DOC activity. For this system, it is estimated that B20-Na resulted in 50% more ash into the DPF. However, the Na did not diffuse into the cordierite DPF nor degrade its mechanical properties. The SCR degradation was found to be caused by a small amount of precious group metals (PGM) contamination that increased NH3 oxidation, and lowered NOx reduction. Therefore, we determined that the primary effect of Na in this study is through increased ash in the DPF rather than deactivation of the catalytic activity.« less

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.

Development and application of a methodology for a clean development mechanism to avoid methane emissions in closed landfills.

PubMed

Janke, Leandro; Lima, André O S; Millet, Maurice; Radetski, Claudemir M

2013-01-01

In Brazil, Solid Waste Disposal Sites have operated without consideration of environmental criteria, these areas being characterized by methane (CH4) emissions during the anaerobic degradation of organic matter. The United Nations organization has made efforts to control this situation, through the United Nations Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol, where projects that seek to reduce the emissions of greenhouse gases (GHG) can be financially rewarded through Certified Emission Reductions (CERs) if they respect the requirements established by the Clean Development Mechanism (CDM), such as the use of methodologies approved by the CDM Executive Board (CDM-EB). Thus, a methodology was developed according to the CDM standards related to the aeration, excavation and composting of closed Municipal Solid Waste (MSW) landfills, which was submitted to CDM-EB for assessment and, after its approval, applied to a real case study in Maringá City (Brazil) with a view to avoiding negative environmental impacts due the production of methane and leachates even after its closure. This paper describes the establishment of this CDM-EB-approved methodology to determine baseline emissions, project emissions and the resultant emission reductions with the application of appropriate aeration, excavation and composting practices at closed MSW landfills. A further result obtained through the application of the methodology in the landfill case study was that it would be possible to achieve an ex-ante emission reduction of 74,013 tCO2 equivalent if the proposed CDM project activity were implemented.

Energy Intensity and Greenhouse Gas Emissions from Tight Oil Production in the Bakken Formation

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

Brandt, Adam R.; Yeskoo, Tim; McNally, Michael S.

The Bakken formation has contributed to the recent rapid increase in U.S. oil production, reaching a peak production of >1.2 × 106 barrels per day in early 2015. In this study, we estimate the energy intensity and greenhouse gas (GHG) emissions from 7271 Bakken wells drilled from 2006 to 2013. We model energy use and emissions using the Oil Production Greenhouse Gas Emissions Estimator (OPGEE) model, supplemented with an open-source drilling and fracturing model, GHGfrack. Overall well-to-refinery-gate (WTR) consumption of natural gas, diesel, and electricity represent 1.3%, 0.2%, and 0.005% of produced crude energy content, respectively. Fugitive emissions are modeledmore » for a “typical” Bakken well using previously published results of atmospheric measurements. Flaring is a key driver of emissions: wells that flared in 2013 had a mean flaring rate that was ≈500 standard cubic feet per barrel or ≈14% of the energy content of the produced crude oil. Resulting production-weighted mean GHG emissions in 2013 were 10.2 g of CO2 equivalent GHGs per megajoule (henceforth, gCO2eq/MJ) of crude. Between-well variability gives a 5–95% range of 2–28 gCO2eq/MJ. If flaring is completely controlled, Bakken crude compares favorably to conventional U.S. crude oil, with 2013 emissions of 3.5 gCO2eq/MJ for nonflaring wells, compared to the U.S. mean of ≈8 gCO2eq/MJ.« less

Control of diesel soot and NOx emissions with a particulate trap and EGR.

PubMed

Liu, Rui-xiang; Gao, Xi-yan; Yang, De-sheng; Xu, Xiao-guang

2005-01-01

The exhaust gas recirculation (EGR), coupled with a high-collection efficiency particulate trap to simultaneously control smoke and NOx emissions from diesel engines were studied. This ceramic trap developed previously provided the soot cleaning efficiency of 99%, the regeneration efficiency reaches 80% and the ratio of success reaches 97%, which make EGR used in diesel possible. At the presence of EGR, opening of the regeneration control valve of the trap was over again optimized to compensate for the decrease of the oxygen concentration in the exhaust gas resulted from EGR. The results indicated the cleaning efficiency and regeneration performance of the trap were maintained at the same level except that the back pressure increased faster. A new EGR system was developed, which is based on a wide range oxygen (UEGO) sensor. Experiments were carried out under steady state conditions while maintaining the engine speed at 1600 r/min, setting the engine loads at 0%, 25%, 50%, 75% and 100% respectively. Throughout each test the EGR rate was kept at nine different settings and data were taken with the gas analyzer and UEGO sensor. Then, the EGR rate and engine load maps, which showed the tendencies of NOx, CO and HC emissions from diesel engine, were made using the measured data. Using the maps, the author set up the EGR regulation, the relationship between the optimal amounts of EGR flow and the equivalence ratio, sigma, where sigma = 14.5/AFR.

Impact of greenhouse gas metrics on the quantification of agricultural emissions and farm-scale mitigation strategies: a New Zealand case study

NASA Astrophysics Data System (ADS)

Reisinger, Andy; Ledgard, Stewart

2013-06-01

Agriculture emits a range of greenhouse gases. Greenhouse gas metrics allow emissions of different gases to be reported in a common unit called CO2-equivalent. This enables comparisons of the efficiency of different farms and production systems and of alternative mitigation strategies across all gases. The standard metric is the 100 year global warming potential (GWP), but alternative metrics have been proposed and could result in very different CO2-equivalent emissions, particularly for CH4. While significant effort has been made to reduce uncertainties in emissions estimates of individual gases, little effort has been spent on evaluating the implications of alternative metrics on overall agricultural emissions profiles and mitigation strategies. Here we assess, for a selection of New Zealand dairy farms, the effect of two alternative metrics (100 yr GWP and global temperature change potentials, GTP) on farm-scale emissions and apparent efficiency and cost effectiveness of alternative mitigation strategies. We find that alternative metrics significantly change the balance between CH4 and N2O; in some cases, alternative metrics even determine whether a specific management option would reduce or increase net farm-level emissions or emissions intensity. However, the relative ranking of different farms by profitability or emissions intensity, and the ranking of the most cost-effective mitigation options for each farm, are relatively unaffected by the metric. We conclude that alternative metrics would change the perceived significance of individual gases from agriculture and the overall cost to farmers if a price were applied to agricultural emissions, but the economically most effective response strategies are unaffected by the choice of metric.

The estimated impact of California’s urban water conservation mandate on electricity consumption and greenhouse gas emissions

NASA Astrophysics Data System (ADS)

Spang, Edward S.; Holguin, Andrew J.; Loge, Frank J.

2018-01-01

In April 2015, the Governor of California mandated a 25% statewide reduction in water consumption (relative to 2013 levels) by urban water suppliers. The more than 400 public water agencies affected by the regulation were also required to report monthly progress towards the conservation goal to the State Water Resources Control Board. This paper uses the reported data to assess how the water utilities have responded to this mandate and to estimate the electricity savings and greenhouse gas (GHG) emissions reductions associated with reduced operation of urban water infrastructure systems. The results show that California succeeded in saving 524 000 million gallons (MG) of water (a 24.5% decrease relative to the 2013 baseline) over the mandate period, which translates into 1830 GWh total electricity savings, and a GHG emissions reduction of 521 000 metric tonnes of carbon dioxide equivalents (MT CO2e). For comparison, the total electricity savings linked to water conservation are approximately 11% greater than the savings achieved by the investor-owned electricity utilities’ efficiency programs for roughly the same time period, and the GHG savings represent the equivalent of taking about 111 000 cars off the road for a year. These indirect, large-scale electricity and GHG savings were achieved at costs that were competitive with existing programs that target electricity and GHG savings directly and independently. Finally, given the breadth of the results produced, we built a companion website, called ‘H2Open’ (https://cwee.shinyapps.io/greengov/), to this research effort that allows users to view and explore the data and results across scales, from individual water utilities to the statewide summary.

Generation and characterization of diesel engine combustion emissions from petroleum diesel and soybean biodiesel fuels and application for inhalation exposure studies.

PubMed

Mutlu, Esra; Nash, David G; King, Charly; Krantz, Todd Q; Preston, William T; Kooter, Ingeborg M; Higuchi, Mark; DeMarini, David; Linak, William P; Gilmour, M Ian

2015-01-01

Biodiesel made from the transesterification of plant- and animal-derived oils is an important alternative fuel source for diesel engines. Although numerous studies have reported health effects associated with petroleum diesel emissions, information on biodiesel emissions are more limited. To this end, a program at the U.S. EPA assessed health effects of biodiesel emissions in rodent inhalation models. Commercially obtained soybean biodiesel (B100) and a 20% blend with petroleum diesel (B20) were compared to pure petroleum diesel (B0). Rats and mice were exposed independently for 4 h/day, 5 days/week for up to 6 weeks. Exposures were controlled by dilution air to obtain low (50 µg/m(3)), medium (150 µg/m(3)) and high (500 µg/m(3)) diesel particulate mass (PM) concentrations, and compared to filtered air. This article provides details on facilities, fuels, operating conditions, emission factors and physico-chemical characteristics of the emissions used for inhalation exposures and in vitro studies. Initial engine exhaust PM concentrations for the B100 fuel (19.7 ± 0.7 mg/m(3)) were 30% lower than those of the B0 fuel (28.0 ± 1.5 mg/m(3)). When emissions were diluted with air to control equivalent PM mass concentrations, B0 exposures had higher CO and slightly lower NO concentrations than B100. Organic/elemental carbon ratios and oxygenated methyl esters and organic acids were higher for the B100 than B0. Both the B0 and B100 fuels produced unimodal-accumulation mode particle-size distributions, with B0 producing lower concentrations of slightly larger particles. Subsequent papers in this series will describe the effects of these atmospheres on cardiopulmonary responses and in vitro genotoxicity studies.

40 CFR 63.626 - Performance tests and compliance provisions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

40 CFR 63.626 - Performance tests and compliance provisions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

40 CFR 63.626 - Performance tests and compliance provisions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... affected facility. P = equivalent P2O5 feed rate, metric ton/hr (ton/hr). K = conversion factor, 1000 mg/g... P2O5 stored, metric tons (tons). K = conversion factor, 1000 mg/g (453,600 mg/lb). (ii) Method 13A or... Where: E = emission rate of total fluorides, g/metric ton (lb/ton) of equivalent P2O5 feed. Csi...

Forest biomass diversion in the Sierra Nevada: Energy, economics and emissions

Treesearch

Bruce Springsteen; Thomas Christofk; Robert A. York; Tad Mason; Stephen Baker; Emily Lincoln; Bruce Hartsough; Takuyuki Yoshioka

2015-01-01

As an alternative to open pile burning, use of forest wastes from fuel hazard reduction projects at Blodgett Forest Research Station for electricity production was shown to produce energy and emission benefits: energy (diesel fuel) expended for processing and transport was 2.5% of the biomass fuel (energy equivalent); based on measurements from a large pile...

40 CFR 63.1205 - What are the standards for hazardous waste burning lightweight aggregate kilns that are effective...

Code of Federal Regulations, 2013 CFR

2013-07-01

... as propane; (6) Hydrochloric acid and chlorine gas in excess of 600 parts per million by volume, combined emissions, expressed as hydrochloric acid equivalents, dry basis and corrected to 7 percent oxygen...) Hydrochloric acid and chlorine gas in excess of 600 parts per million by volume, combined emissions, expressed...

40 CFR 63.1205 - What are the standards for hazardous waste burning lightweight aggregate kilns that are effective...

Code of Federal Regulations, 2014 CFR

2014-07-01

... as propane; (6) Hydrochloric acid and chlorine gas in excess of 600 parts per million by volume, combined emissions, expressed as hydrochloric acid equivalents, dry basis and corrected to 7 percent oxygen...) Hydrochloric acid and chlorine gas in excess of 600 parts per million by volume, combined emissions, expressed...

40 CFR 63.7740 - What are my monitoring requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... pressure baghouse equipped with a stack that is applied to meet any PM or total metal HAP emissions..., that is applied to meet any PM or total metal HAP emissions limitation in this subpart, you must... detectors, or equivalent means. (d) For each wet scrubber subject to the operating limits in § 63.7690(b)(2...

Historical and projected emissions of HCFC-22 and HFC-410A from China's room air conditioning sector

NASA Astrophysics Data System (ADS)

Wang, Ziyuan; Fang, Xuekun; Li, Li; Bie, Pengju; Li, Zhifang; Hu, Jianxin; Zhang, Boya; Zhang, Jianbo

2016-05-01

Recent decades witnessed the increase in production and uses of HCFC-22 (chlorodifluoromethane, CHClF2) and its alternative, HFC-410A (a blend of difluoromethane and pentafluoroethane), in China in response to the booming of room air conditioners (RACs) for both domestic use and exports. HCFC-22 is an ozone-depleting substance under the Montreal Protocol, while both HCFC-22 and HFC-410A are greenhouse gases (GHGs). This study provides a most comprehensive consumption and emission inventory of refrigerants emissions (HCFC-22 and HFC-410A) from RAC sector during 1995-2014, for the first time. Our estimates show that HCFC-22 emissions increased from 0.7 Gg/yr in 1995 to 48.2 Gg/yr in 2014. The accumulative emissions contributed to global total HCFCs emissions by 4.4% (3.3%-6.1%) CFC-11-equivalent (CFC-11-eq) and 5.4% (4.1%-7.5%) CO2-equivalent (CO2-eq) during 1995-2012. If left uncontrolled, accumulative emissions of HFC-410A will be12.4 (7.1-20.2) CO2-eq Pg during 2015-2050, which can offset the global climate benefits achieved by the Montreal Protocol. The HFC-410A emissions from China's RAC sector are estimated to be of importance to both global HFCs emissions and China's GHG emissions. Further, we probed the emission mitigation performances of the current 2014 North American Proposal scenario and a modified more ambitious scenario. The emissions of two mitigation scenarios are only 28% and 22% of the emissions without mitigation actions, respectively. This study is the first effort to map the transition of eliminated substance HCFC-22 and its alternative HFC-410A in RAC sector. Therefore, alternative chemicals should be scrutinized with cautions before they are promoted and applied.

Exploiting Co-Benefits of Increased Rice Production and Reduced Greenhouse Gas Emission through Optimized Crop and Soil Management.

PubMed

An, Ning; Fan, Mingsheng; Zhang, Fusuo; Christie, Peter; Yang, Jianchang; Huang, Jianliang; Guo, Shiwei; Shi, Xiaojun; Tang, Qiyuan; Peng, Jianwei; Zhong, Xuhua; Sun, Yixiang; Lv, Shihua; Jiang, Rongfeng; Dobermann, Achim

2015-01-01

Meeting the future food security challenge without further sacrificing environmental integrity requires transformative changes in managing the key biophysical determinants of increasing agronomic productivity and reducing the environmental footprint. Here, we focus on Chinese rice production and quantitatively address this concern by conducting 403 on-farm trials across diverse rice farming systems. Inherent soil productivity, management practices and rice farming type resulted in confounded and interactive effects on yield, yield gaps and greenhouse gas (GHG) emissions (N2O, CH4 and CO2-equivalent) with both trade-offs and compensating effects. Advances in nitrogen, water and crop management (Best Management Practices-BMPs) helped closing existing yield gaps and resulted in a substantial reduction in CO2-equivalent emission of rice farming despite a tradeoff of increase N2O emission. However, inherent soil properties limited rice yields to a larger extent than previously known. Cultivating inherently better soil also led to lower GHG intensity (GHG emissions per unit yield). Neither adopting BMPs only nor improving soils with low or moderate productivity alone can adequately address the challenge of substantially increasing rice production while reducing the environmental footprint. A combination of both represents the most efficient strategy to harness the combined-benefits of enhanced production and mitigating climate change. Extrapolating from our farm data, this strategy could increase rice production in China by 18%, which would meet the demand for direct human consumption of rice by 2030. It would also reduce fertilizer nitrogen consumption by 22% and decrease CO2-equivalent emissions during the rice growing period by 7% compared with current farming practice continues. Benefits vary by rice-based cropping systems. Single rice systems have the largest food provision benefits due to its wider yield gap and total cultivated area, whereas double-rice system (especially late rice) contributes primarily to reducing GHG emissions. The study therefore provides farm-based evidence for feasible, practical approaches towards achieving realistic food security and environmental quality targets at a national scale.

Exploiting Co-Benefits of Increased Rice Production and Reduced Greenhouse Gas Emission through Optimized Crop and Soil Management

PubMed Central

An, Ning; Fan, Mingsheng; Zhang, Fusuo; Christie, Peter; Yang, Jianchang; Huang, Jianliang; Guo, Shiwei; Shi, Xiaojun; Tang, Qiyuan; Peng, Jianwei; Zhong, Xuhua; Sun, Yixiang; Lv, Shihua; Jiang, Rongfeng; Dobermann, Achim

2015-01-01

Meeting the future food security challenge without further sacrificing environmental integrity requires transformative changes in managing the key biophysical determinants of increasing agronomic productivity and reducing the environmental footprint. Here, we focus on Chinese rice production and quantitatively address this concern by conducting 403 on-farm trials across diverse rice farming systems. Inherent soil productivity, management practices and rice farming type resulted in confounded and interactive effects on yield, yield gaps and greenhouse gas (GHG) emissions (N2O, CH4 and CO2-equivalent) with both trade-offs and compensating effects. Advances in nitrogen, water and crop management (Best Management Practices—BMPs) helped closing existing yield gaps and resulted in a substantial reduction in CO2-equivalent emission of rice farming despite a tradeoff of increase N2O emission. However, inherent soil properties limited rice yields to a larger extent than previously known. Cultivating inherently better soil also led to lower GHG intensity (GHG emissions per unit yield). Neither adopting BMPs only nor improving soils with low or moderate productivity alone can adequately address the challenge of substantially increasing rice production while reducing the environmental footprint. A combination of both represents the most efficient strategy to harness the combined-benefits of enhanced production and mitigating climate change. Extrapolating from our farm data, this strategy could increase rice production in China by 18%, which would meet the demand for direct human consumption of rice by 2030. It would also reduce fertilizer nitrogen consumption by 22% and decrease CO2-equivalent emissions during the rice growing period by 7% compared with current farming practice continues. Benefits vary by rice-based cropping systems. Single rice systems have the largest food provision benefits due to its wider yield gap and total cultivated area, whereas double-rice system (especially late rice) contributes primarily to reducing GHG emissions. The study therefore provides farm-based evidence for feasible, practical approaches towards achieving realistic food security and environmental quality targets at a national scale. PMID:26452155

Experimental Investigation of a Multiplex Fuel Injector Module With Discrete Jet Swirlers for Low Emission Combustors

NASA Technical Reports Server (NTRS)

Tacina, Robert; Mao, Chien-Pei; Wey, Changlie

2004-01-01

A low-NOx emissions combustor concept has been demonstrated in flame-tube tests. A lean-direct injection (LDI) concept was used where the fuel is injected directly into the flame zone and the overall equivalence ratio of the mixture is lean. The LDI concept described in this report is a multiplex fuel injector module containing multipoint fuel injection tips and multi-burning zones. The injector module comprises 25 equally spaced injection tips within a 76 by 76 mm area that fits into the flame-tube duct. The air swirlers were made from a concave plate on the axis of the fuel injector using drilled holes at an angle to the axis of the fuel injector. The NOx levels were quite low and are greater than 70 percent lower than the 1996 ICAO standard. At an inlet temperature of 810 K, inlet pressure of 2760 kPa, pressure drop of 4 percent and a flame temperature of 1900 K with JP8 fuel, the NOx emission index was 9. The 25-point injector module exhibited the most uniform radial distribution of fuel-air mixture and NOx emissions in the flame tube when compared to other multipoint injection devices. A correlation is developed relating the NOx emissions to inlet temperature, inlet pressure, equivalence ratio and pressure drop.

40 CFR 63.41 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... existing equipment will be equivalent to that level of control currently achieved by other well-controlled similar sources (i.e., equivalent to the level of control that would be provided by a current BACT, LAER... control equipment will be equivalent to the percent control efficiency provided by the control equipment...

40 CFR 63.41 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... existing equipment will be equivalent to that level of control currently achieved by other well-controlled similar sources (i.e., equivalent to the level of control that would be provided by a current BACT, LAER... control equipment will be equivalent to the percent control efficiency provided by the control equipment...

40 CFR 63.41 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... existing equipment will be equivalent to that level of control currently achieved by other well-controlled similar sources (i.e., equivalent to the level of control that would be provided by a current BACT, LAER... control equipment will be equivalent to the percent control efficiency provided by the control equipment...

40 CFR 63.41 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... existing equipment will be equivalent to that level of control currently achieved by other well-controlled similar sources (i.e., equivalent to the level of control that would be provided by a current BACT, LAER... control equipment will be equivalent to the percent control efficiency provided by the control equipment...

40 CFR 63.41 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... existing equipment will be equivalent to that level of control currently achieved by other well-controlled similar sources (i.e., equivalent to the level of control that would be provided by a current BACT, LAER... control equipment will be equivalent to the percent control efficiency provided by the control equipment...

Coupling the snow thermodynamic model SNOWPACK with the microwave emission model of layered snowpacks for subarctic and arctic snow water equivalent retrievals

NASA Astrophysics Data System (ADS)

Langlois, A.; Royer, A.; Derksen, C.; Montpetit, B.; Dupont, F.; GoïTa, K.

2012-12-01

Satellite-passive microwave remote sensing has been extensively used to estimate snow water equivalent (SWE) in northern regions. Although passive microwave sensors operate independent of solar illumination and the lower frequencies are independent of atmospheric conditions, the coarse spatial resolution introduces uncertainties to SWE retrievals due to the surface heterogeneity within individual pixels. In this article, we investigate the coupling of a thermodynamic multilayered snow model with a passive microwave emission model. Results show that the snow model itself provides poor SWE simulations when compared to field measurements from two major field campaigns. Coupling the snow and microwave emission models with successive iterations to correct the influence of snow grain size and density significantly improves SWE simulations. This method was further validated using an additional independent data set, which also showed significant improvement using the two-step iteration method compared to standalone simulations with the snow model.

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.

40 CFR 62.15205 - What minimum amount of monitoring data must I collect with my continuous emission monitoring...

Code of Federal Regulations, 2014 CFR

2014-07-01

... averages for sulfur dioxide, nitrogen oxides (Class I municipal waste combustion units only), and carbon monoxide are in parts per million by dry volume at 7 percent oxygen (or the equivalent carbon dioxide level). Use the 1-hour averages of oxygen (or carbon dioxide) data from your continuous emission monitoring...

40 CFR 62.15205 - What minimum amount of monitoring data must I collect with my continuous emission monitoring...

Code of Federal Regulations, 2013 CFR

2013-07-01

... averages for sulfur dioxide, nitrogen oxides (Class I municipal waste combustion units only), and carbon monoxide are in parts per million by dry volume at 7 percent oxygen (or the equivalent carbon dioxide level). Use the 1-hour averages of oxygen (or carbon dioxide) data from your continuous emission monitoring...

40 CFR 62.15205 - What minimum amount of monitoring data must I collect with my continuous emission monitoring...

Code of Federal Regulations, 2012 CFR

2012-07-01

... averages for sulfur dioxide, nitrogen oxides (Class I municipal waste combustion units only), and carbon monoxide are in parts per million by dry volume at 7 percent oxygen (or the equivalent carbon dioxide level). Use the 1-hour averages of oxygen (or carbon dioxide) data from your continuous emission monitoring...

Mapping rice ecosystem dynamics and greenhouse gas emissions using multiscale imagery and biogeochemical models

NASA Astrophysics Data System (ADS)

Salas, W.; Torbick, N.

2017-12-01

Rice greenhouse gas (GHG) emissions in production hot spots have been mapped using multiscale satellite imagery and a processed-based biogeochemical model. The multiscale Synthetic Aperture Radar (SAR) and optical imagery were co-processed and fed into a machine leanring framework to map paddy attributes that are tuned using field observations and surveys. Geospatial maps of rice extent, crop calendar, hydroperiod, and cropping intensity were then used to parameterize the DeNitrification-DeComposition (DNDC) model to estimate emissions. Results, in the Red River Detla for example, show total methane emissions at 345.4 million kgCH4-C equivalent to 11.5 million tonnes CO2e (carbon dioxide equivalent). We further assessed the role of Alternative Wetting and Drying and the impact on GHG and yield across production hot spots with uncertainty estimates. The approach described in this research provides a framework for using SAR to derive maps of rice and landscape characteristics to drive process models like DNDC. These types of tools and approaches will support the next generation of Monitoring, Reporting, and Verification (MRV) to combat climate change and support ecosystem service markets.

A SUZAKU OBSERVATION OF Mkn 590 REVEALS A VANISHING SOFT EXCESS

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

Rivers, Elizabeth; Markowitz, Alex; Rothschild, Richard

2012-11-01

We have analyzed a long-look Suzaku observation of the Seyfert 1.2 Mkn 590. We aimed to measure the Compton reflection strength, Fe K complex properties, and soft excess emission as had been observed previously in this source. The Compton reflection strength was measured to be in the range 0.2-1.0 depending on the model used. A moderately strong Fe K{alpha} emission line was detected with an equivalent width of {approx}120 {+-} 25 eV and an Fe K{beta} line was identified with an equivalent width of {approx}30 {+-} 20 eV, although we could not rule out contribution from ionized Fe emission atmore » this energy. Surprisingly, we found no evidence for soft excess emission. Comparing our results with a 2004 observation from XMM-Newton we found that either the soft excess has decreased by a factor of 20-30 in 7 years or the photon index has steepened by 0.10 (with no soft excess present) while the continuum flux in the range 2-10 keV has varied only minimally (10%). This result could support recent claims that the soft excess is independent of the X-ray continuum.« less

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.

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.

Static magnetic field (SMF) sensing of the P(723)/P(689) photosynthetic complex.

PubMed

Bhattacharya, Abhishek; Chakraborty, Madhurima; Raja, Sufi O; Ghosh, Avijit; Dasgupta, Maitrayee; Dasgupta, Anjan Kr

2014-12-01

Moderate intensity SMF have been shown to act as a controller of the protic potential in the coherent milieu of the thylakoid membranes. SMF of the order of 60-500 mT induces memory-like effect in photosystem I (PSI, P723) emission with a correlated oscillation of photosystem II (PSII, P689) fluorescence emission at a temperature of 77 K. The observed magnetic perturbation that affects the thylakoid photon capture circuitry was also found to be associated with the bio-energetic machinery of the thylakoid membranes. At normal pH, SMF causes an enhancement of PSI fluorescence emission intensity (P723/P689 > 1), followed by a slow relaxation on the removal of SMF. The enhancement of the PSI fluorescence intensity also occurs under no-field condition, if either the pH of the medium is lowered, or protonophores, such as carbonyl cyanide chlorophenylhydrazine or nigericin are added (P723/P689≥ 2). If SMF was applied under such a low pH condition or in the presence of protonophore, a reverse effect, particularly, a reduction of the enhanced PSI emission was observed. Because SMF is essentially equivalent to a spin perturbation, the observed effects can be explained in terms of spin re-organization, illustrating a memory effect via membrane re-alignment and assembly. The mimicry of conventional uncouplers by SMF is also notable; the essential difference being the reversibility and manoeuvrability of the latter (SMF). Finally, the effect implies numerous possibilities of externally regulating the photon capture and proton circulation in the thylakoid membranes using controlled SMF.

Flame tube parametric studies for control of fuel bound nitrogen using rich-lean two-stage combustion

NASA Technical Reports Server (NTRS)

Schultz, D. F.; Wolfbrandt, G.

1980-01-01

An experimental parametric study of rich-lean two-stage combustion in a flame tube is described and approaches for minimizing the conversion of fuel-bound nitrogen to nitrogen oxides in a premixed, homogeneous combustion system are evaluated. Air at 672 K and 0.48 MPa was premixed with fuel blends of propane, toluene, and pyridine at primary equivalence ratios ranging from 0.5 to 2.0 and secondary equivalence ratios of 0.5 to 0.7. Distillates of SRC-II, a coal syncrude, were also tested. The blended fuels were proportioned to vary fuel hydrogen composition from 9.0 to 18.3 weight percent and fuel nitrogen composition from zero to 1.5 weight percent. Rich-lean combustion proved effective in reducing fuel nitrogen to NO sub x conversion; conversion rates up to 10 times lower than those normally produced by single-stage combustion were achieved. The optimum primary equivalence ratio, where the least NO sub x was produced and combustion efficiency was acceptable, shifted between 1.4 and 1.7 with changes in fuel nitrogen content and fuel hydrogen content. Increasing levels of fuel nitrogen content lowered the conversion rate, but not enough to avoid higher NO sub x emissions as fuel nitrogen increased.

About the RAD Program

EPA Pesticide Factsheets

EPA serves as a technical clearinghouse on responsible appliance disposal program development and implementation; calculates annual and cumulative program benefits in terms of ODS and GHG emission savings and equivalents, etc.

Mass transfer inside a flux hood for the sampling of gaseous emissions from liquid surfaces - Experimental assessment and emission rate rescaling

NASA Astrophysics Data System (ADS)

Prata, Ademir A.; Lucernoni, Federico; Santos, Jane M.; Capelli, Laura; Sironi, Selena; Le-Minh, Nhat; Stuetz, Richard M.

2018-04-01

This study assesses the mass transfer of compounds inside the US EPA flux hood, one of the enclosure devices most commonly employed for the direct measurement of atmospheric emissions from liquid surfaces in wastewater treatment plants (WWTPs). Experiments comprised the evaporation of water and the volatilisation of a range of volatile organic compounds (VOCs). Special attention was given to the evaluation of the mass transfer coefficients in the microenvironment created by the flux hood and the effects of concentration build up in the hood's headspace. The VOCs emission rates and the water evaporation rates generally increased with the sweep air flow rate, as did the mass transfer coefficients for all compounds. The emission of compounds whose volatilisation is significantly influenced by the gas phase was greatly affected by concentration build up, whereas this effect was not significant for liquid phase-controlled compounds. The gas-film mass transfer coefficient (kG) estimated inside the US EPA flux hood was of the same order as the respective kG reported in the literature for wind tunnel-type devices, but the emission rates measured by the flux hood can be expected to be lower, due to the concentration build-up. Compared against an emission model for the passive surfaces in WWTPs, the mass transfer of acetic acid (representing a gas phase-dominated compound) inside the US EPA flux hood was equivalent to conditions of wind speeds at 10 m height (U10) of 0.27, 0.51 and 0.99 m s-1, respectively, for sweep air flow rates of 2, 5 and 10 L min-1. On the other hand, for higher wind speeds, the emission rates of gas phase-controlled compounds obtained with the flux hood can be considerably underestimated: for instance, at U10 = 5 m s-1, the emission rates of acetic acid inside the flux hood would be approximately 23, 12 and 6 times lower than the emission rates in the field, for sweep air flow rates of 2, 5 and 10 L min-1, respectively. A procedure is presented in order to scale the emission rates of these compounds measured with the flux hood to field conditions of higher winds.

Scanning probe microscopy and field emission schemes for studying electron emission from polycrystalline diamond

NASA Astrophysics Data System (ADS)

Chubenko, Oksana; Baturin, Stanislav S.; Baryshev, Sergey V.

2016-09-01

The letter introduces a diagram that rationalizes tunneling atomic force microscopy (TUNA) observations of electron emission from polycrystalline diamonds as described in the recent publications [Chatterjee et al., Appl. Phys. Lett. 104, 171907 (2014); Harniman et al., Carbon 94, 386 (2015)]. The direct observations of electron emission from the grain boundary sites by TUNA could indeed be the evidence of electrons originating from grain boundaries under external electric fields. At the same time, from the diagram, it follows that TUNA and field emission schemes are complimentary rather than equivalent for results interpretation. It is further proposed that TUNA could provide better insights into emission mechanisms by measuring the detailed structure of the potential barrier on the surface of polycrystalline diamonds.

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.

Determining size-specific emission factors for environmental tobacco smoke particles

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

Klepeis, Neil E.; Apte, Michael G.; Gundel, Lara A.

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

Reducing the environmental impact of trials: a comparison of the carbon footprint of the CRASH-1 and CRASH-2 clinical trials

PubMed Central

2011-01-01

Background All sectors of the economy, including the health research sector, must reduce their carbon emissions. The UK National Institute for Health Research has recently prepared guidelines on how to minimize the carbon footprint of research. We compare the carbon emissions from two international clinical trials in order to identify where emissions reductions can be made. Methods We conducted a carbon audit of two clinical trials (the CRASH-1 and CRASH-2 trials), quantifying the carbon dioxide emissions produced over a one-year audit period. Carbon emissions arising from the coordination centre, freight delivery, trial-related travel and commuting were calculated and compared. Results The total emissions in carbon dioxide equivalents during the one-year audit period were 181.3 tonnes for CRASH-1 and 108.2 tonnes for CRASH-2. In total, CRASH-1 emitted 924.6 tonnes of carbon dioxide equivalents compared with 508.5 tonnes for CRASH-2. The CRASH-1 trial recruited 10,008 patients over 5.1 years, corresponding to 92 kg of carbon dioxide per randomized patient. The CRASH-2 trial recruited 20,211 patients over 4.7 years, corresponding to 25 kg of carbon dioxide per randomized patient. The largest contributor to emissions in CRASH-1 was freight delivery of trial materials (86.0 tonnes, 48% of total emissions), whereas the largest contributor in CRASH-2 was energy use by the trial coordination centre (54.6 tonnes, 30% of total emissions). Conclusions Faster patient recruitment in the CRASH-2 trial largely accounted for its greatly increased carbon efficiency in terms of emissions per randomized patient. Lighter trial materials and web-based data entry also contributed to the overall lower carbon emissions in CRASH-2 as compared to CRASH-1. Trial Registration Numbers CRASH-1: ISRCTN74459797 CRASH-2: ISRCTN86750102 PMID:21291517

Inventory and mitigation opportunities for HFC-134a emissions from nonprofessional automotive service

NASA Astrophysics Data System (ADS)

Zhan, Tao; Potts, Winston; Collins, John F.; Austin, Jeff

2014-12-01

Many vehicle owners in the United States recharge their vehicles' air conditioning systems with small containers of hydrofluorocarbon-134a (HFC-134a, CH2FCF3), at a frequency estimated to be once every year on average. Such nonprofessional service produces immediate emissions of this potent greenhouse gas during service and from the residual heel in partially used containers. The nonprofessional operations are also associated with increased delayed refrigerant emissions that occur because owners are less likely to repair leaks than professional technicians. In California, an estimated 1.3 million nonprofessional service operations performed each year generate 0.27 ± 0.07 million metric ton CO2 equivalent (MMTCO2e) of immediate emissions and 0.54 ± 0.08 MMTCO2e of delayed emissions, using a Global Warming Potential of 1300 for HFC-134a. The immediate emissions can be largely mitigated by a regulation that requires self-sealing valves and improved labeling instructions on the containers, a deposit-return-recycling program for the containers, and a consumer education program. If 95% of the used containers were to be returned by consumers for recycling of the container heel, the annual immediate emissions would be reduced by 0.26 ± 0.07 MMTCO2e. In the United States, an estimated 24 million nonprofessional service operations are performed each year, generating 5.1 ± 1.4 MMTCO2e of immediate emissions and 10.4 ± 1.5 MMTCO2e of delayed emissions. Mitigation measures equivalent to the California regulation would reduce nationwide immediate emissions by 4.9 ± 1.4 MMTCO2e, if 95% of the used cans were returned for recycling. These business-as-usual emissions and mitigation potentials are projected to stay approximately constant until around 2022, and remain at significant levels into the 2030s.

A comparison of CH4, N2O and CO2 emissions from three different cover types in a municipal solid waste landfill.

PubMed

Wang, Xiaojun; Jia, Mingsheng; Lin, Xiangyu; Xu, Ying; Ye, Xin; Kao, Chih Ming; Chen, Shaohua

2017-04-01

High-density polyethylene (HDPE) membranes are commonly used as a cover component in sanitary landfills, although only limited evaluations of its effect on greenhouse gas (GHG) emissions have been completed. In this study, field GHG emission were investigated at the Dongbu landfill, using three different cover systems: HDPE covering; no covering, on the working face; and a novel material-Oreezyme Waste Cover (OWC) material as a trial material. Results showed that the HDPE membrane achieved a high CH 4 retention, 99.8% (CH 4 mean flux of 12 mg C m -2 h -1 ) compared with the air-permeable OWC surface (CH4 mean flux of 5933 mg C m -2 h -1 ) of the same landfill age. Fresh waste at the working face emitted a large fraction of N 2 O, with average fluxes of 10 mg N m -2 h -2 , while N 2 O emissions were small at both the HDPE and the OWC sections. At the OWC section, CH 4 emissions were elevated under high air temperatures but decreased as landfill age increased. N 2 O emissions from the working face had a significant negative correlation with air temperature, with peak values in winter. A massive presence of CO 2 was observed at both the working face and the OWC sections. Most importantly, the annual GHG emissions were 4.9 Gg yr -1 in CO 2 equivalents for the landfill site, of which the OWC-covered section contributed the most CH 4 (41.9%), while the working face contributed the most N 2 O (97.2%). HDPE membrane is therefore, a recommended cover material for GHG control. Monitoring of GHG emissions at three different cover types in a municipal solid waste landfill during a 1-year period showed that the working face was a hotspot of N 2 O, which should draw attention. High CH 4 fluxes occurred on the permeable surface covering a 1- to 2-year-old landfill. In contrast, the high-density polyethylene (HDPE) membrane achieved high CH 4 retention, and therefore is a recommended cover material for GHG control.

An Assessment of Combustion Dynamics in a Low-Nox, Second-Generation Swirl-Venturi Lean Direct Injection Combustion Concept

NASA Technical Reports Server (NTRS)

Tacina, K. M.; Chang, C. T.; Lee, P.; Mongia, H.; Podboy, D. P.; Dam, B.

2015-01-01

Dynamic pressure measurements were taken during flame-tube emissions testing of three second-generation swirl-venturi lean direct injection (SV-LDI) combustor configurations. These measurements show that combustion dynamics were typically small. However, a small number of points showed high combustion dynamics, with peak-to-peak dynamic pressure fluctuations above 0.5 psi. High combustion dynamics occurred at low inlet temperatures in all three SV-LDI configurations, so combustion dynamics were explored further at low temperature conditions. A point with greater than 1.5 psi peak-to-peak dynamic pressure fluctuations was identified at an inlet temperature of 450!F, a pressure of 100 psia, an air pressure drop of 3%, and an overall equivalence ratio of 0.35. This is an off design condition: the temperature and pressure are typical of 7% power conditions, but the equivalence ratio is high. At this condition, the combustion dynamics depended strongly on the fuel staging. Combustion dynamics could be reduced significantly without changing the overall equivalence ratio by shifting the fuel distribution between stages. Shifting the fuel distribution also decreased NOx emissions.

Universal modal radiation laws for all thermal emitters

PubMed Central

Zhu, Linxiao; Fan, Shanhui

2017-01-01

We derive four laws relating the absorptivity and emissivity of thermal emitters. Unlike the original Kirchhoff radiation law derivations, these derivations include diffraction, and so are valid also for small objects, and can also cover nonreciprocal objects. The proofs exploit two recent approaches. First, we express all fields in terms of the mode-converter basis sets of beams; these sets, which can be uniquely established for any linear optical object, give orthogonal input beams that are coupled one-by-one to orthogonal output beams. Second, we consider thought experiments using universal linear optical machines, which allow us to couple appropriate beams and black bodies. Two of these laws can be regarded as rigorous extensions of previously known laws: One gives a modal version of a radiation law for reciprocal objects—the absorptivity of any input beam equals the emissivity into the “backward” (i.e., phase-conjugated) version of that beam; another gives the overall equality of the sums of the emissivities and the absorptivities for any object, including nonreciprocal ones. The other two laws, valid for reciprocal and nonreciprocal objects, are quite different from previous relations. One shows universal equivalence of the absorptivity of each mode-converter input beam and the emissivity into its corresponding scattered output beam. The other gives unexpected equivalences of absorptivity and emissivity for broad classes of beams. Additionally, we prove these orthogonal mode-converter sets of input and output beams are the ones that maximize absorptivities and emissivities, respectively, giving these beams surprising additional physical meaning. PMID:28396436

Global warming potential of manure amended soils under rice-wheat system in the Indo-Gangetic plains

NASA Astrophysics Data System (ADS)

Bhatia, A.; Pathak, H.; Jain, N.; Singh, P. K.; Singh, A. K.

Use of organic amendments such as farmyard manure (FYM), green manure (GM) and crop residues is important to improve soil health and reduce the dependence on synthetic chemical fertilizer. However, these organic amendments also effect the emissions of greenhouse gas (GHG) from soil. Influence of different organic amendments on emissions of GHG from soil and their global warming potential (GWP) was studied in a field experiment in rice-wheat cropping system of Indo-Gangetic plains (IGP). There was 28% increase in CH 4 emissions on addition of 25% N through Sesbania GM along with urea compared to urea alone. Substitution of 100% inorganic N by organic sources lead to a 60% increase in CH 4 emissions. The carbon equivalent emission from rice-wheat systems varied between 3816 and 4886 kg C equivalent ha -1 depending upon fertilizer and organic amendment. GWP of rice-wheat system increased by 28% on full substitution of organic N by chemical N. However, the C efficiency ratios of the GM and crop residue treatments were at par with the recommended inorganic fertilizer treatment. Thus use of organic amendments along with inorganic fertilizer increases the GWP of the rice-wheat system but may improve the soil fertility status without adversely affecting the C efficiency ratio. However, the trade-off between improved yield and soil health versus GHG emissions should be taken into account while promoting the practice of farming with organic residues substitution for mineral fertilizer.

Equivalent radiation source of 3D package for electromagnetic characteristics analysis

NASA Astrophysics Data System (ADS)

Li, Jun; Wei, Xingchang; Shu, Yufei

2017-10-01

An equivalent radiation source method is proposed to characterize electromagnetic emission and interference of complex three dimensional integrated circuits (IC) in this paper. The method utilizes amplitude-only near-field scanning data to reconstruct an equivalent magnetic dipole array, and the differential evolution optimization algorithm is proposed to extract the locations, orientation and moments of those dipoles. By importing the equivalent dipoles model into a 3D full-wave simulator together with the victim circuit model, the electromagnetic interference issues in mixed RF/digital systems can be well predicted. A commercial IC is used to validate the accuracy and efficiency of this proposed method. The coupled power at the victim antenna port calculated by the equivalent radiation source is compared with the measured data. Good consistency is obtained which confirms the validity and efficiency of the method. Project supported by the National Nature Science Foundation of China (No. 61274110).

Ultraviolet emission lines in young low-mass galaxies at z ≃ 2: physical properties and implications for studies at z > 7

NASA Astrophysics Data System (ADS)

Stark, Daniel P.; Richard, Johan; Siana, Brian; Charlot, Stéphane; Freeman, William R.; Gutkin, Julia; Wofford, Aida; Robertson, Brant; Amanullah, Rahman; Watson, Darach; Milvang-Jensen, Bo

2014-12-01

We present deep spectroscopy of 17 very low mass (M⋆ ≃ 2.0 × 106-1.4 × 109 M⊙) and low luminosity (MUV ≃ -13.7 to -19.9) gravitationally lensed galaxies in the redshift range z ≃ 1.5-3.0. Deep rest-frame ultraviolet spectra reveal large equivalent width emission from numerous emission lines (N IV], O III], C IV, Si III], C III]) which are rarely seen in individual spectra of more massive star-forming galaxies. C III] is detected in 16 of 17 low-mass star-forming systems with rest-frame equivalent widths as large as 13.5 Å. Nebular C IV emission is present in the most extreme C III] emitters, requiring an ionizing source capable of producing a substantial component of photons with energies in excess of 47.9 eV. Photoionization models support a picture whereby the large equivalent widths are driven by the increased electron temperature and enhanced ionizing output arising from metal-poor gas and stars (0.04-0.13 Z⊙), young stellar populations (6-50 Myr), and large ionization parameters (log U = -2.16 to -1.84). The young ages implied by the emission lines and continuum spectral energy distributions (SEDs) indicate that the extreme line emitters in our sample are in the midst of a significant upturn in their star formation activity. The low stellar masses, blue UV colours, and large specific star formation rates of our sample are similar to those of typical z ≳ 6 galaxies. Given the strong attenuation of Lyα in z ≳ 6 galaxies, we suggest that C III] is likely to provide our best probe of early star-forming galaxies with ground-based spectrographs and one off the most efficient means of confirming z ≳ 10 galaxies with the James Webb Space Telescope.

A study on emission characteristics of an EFI engine with ethanol blended gasoline fuels

NASA Astrophysics Data System (ADS)

He, Bang-Quan; Wang, Jian-Xin; Hao, Ji-Ming; Yan, Xiao-Guang; Xiao, Jian-Hua

The effect of ethanol blended gasoline fuels on emissions and catalyst conversion efficiencies was investigated in a spark ignition engine with an electronic fuel injection (EFI) system. The addition of ethanol to gasoline fuel enhances the octane number of the blended fuels and changes distillation temperature. Ethanol can decrease engine-out regulated emissions. The fuel containing 30% ethanol by volume can drastically reduce engine-out total hydrocarbon emissions (THC) at operating conditions and engine-out THC, CO and NO x emissions at idle speed, but unburned ethanol and acetaldehyde emissions increase. Pt/Rh based three-way catalysts are effective in reducing acetaldehyde emissions, but the conversion of unburned ethanol is low. Tailpipe emissions of THC, CO and NO x have close relation to engine-out emissions, catalyst conversion efficiency, engine's speed and load, air/fuel equivalence ratio. Moreover, the blended fuels can decrease brake specific energy consumption.

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.

Evaluating impacts of air pollution in China on public health: Implications for future air pollution and energy policies

NASA Astrophysics Data System (ADS)

Wang, Xiaoping; Mauzerall, Denise L.

Our objective is to establish the link between energy consumption and technologies, air pollution concentrations, and resulting impacts on public health in eastern China. We use Zaozhuang, a city in eastern China heavily dependent on coal, as a case study to quantify the impacts that air pollution in eastern China had on public health in 2000 and the benefits in improved air quality and health that could be obtained by 2020, relative to business-as-usual (BAU), through the implementation of best available emission control technology (BACT) and advanced coal gasification technologies (ACGT). We use an integrated assessment approach, utilizing state-of-the-science air quality and meteorological models, engineering, epidemiology, and economics, to achieve this objective. We find that total health damages due to year 2000 anthropogenic emissions from Zaozhuang, using the "willingness-to-pay" metric, was equivalent to 10% of Zaozhuang's GDP. If all health damages resulting from coal use were internalized in the market price of coal, the year 2000 price would have more than tripled. With no new air pollution controls implemented between 2000 and 2020 but with projected increases in energy use, we estimate health damages from air pollution exposure to be equivalent to 16% of Zaozhuang's projected 2020 GDP. BACT and ACGT (with only 24% penetration in Zaozhuang and providing 2% of energy needs in three surrounding municipalities) could reduce the potential health damage of air pollution in 2020 to 13% and 8% of projected GDP, respectively. Benefits to public health, of substantial monetary value, can be achieved through the use of BACT; health benefits from the use of ACGT could be even larger. Despite significant uncertainty associated with each element of the integrated assessment approach, we demonstrate that substantial benefits to public health could be achieved in this region of eastern China through the use of additional pollution controls and particularly from the use of advanced coal gasification technology. Without such controls, the impacts of air pollution on public health, presently considerable, will increase substantially by 2020.

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2014 CFR

2014-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2012 CFR

2012-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2011 CFR

2011-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

49 CFR 624.3 - Eligible activities.

Code of Federal Regulations, 2013 CFR

2013-10-01

...— (1) Is powered by— (i) Compressed natural gas; (ii) Liquefied natural gas; (iii) Biodiesel fuels; (iv... clean fuel, biodiesel, hybrid electric, or zero emissions technology buses that exhibit equivalent or...

'Herbal' but potentially hazardous: an analysis of the constituents and smoke emissions of tobacco-free waterpipe products and the air quality in the cafés where they are served.

PubMed

Hammal, Fadi; Chappell, Alyssa; Wild, T Cameron; Kindzierski, Warren; Shihadeh, Alan; Vanderhoek, Amanda; Huynh, Cong Khanh; Plateel, Gregory; Finegan, Barry A

2015-05-01

There are limited data on the composition and smoke emissions of 'herbal' shisha products and the air quality of establishments where they are smoked. Three studies of 'herbal' shisha were conducted: (1) samples of 'herbal' shisha products were chemically analysed; (2) 'herbal' and tobacco shisha were burned in a waterpipe smoking machine and main and sidestream smoke analysed by standard methods and (3) the air quality of six waterpipe cafés was assessed by measurement of CO, particulate and nicotine vapour content. We found considerable variation in heavy metal content between the three products sampled, one being particularly high in lead, chromium, nickel and arsenic. A similar pattern emerged for polycyclic aromatic hydrocarbons. Smoke emission analyses indicated that toxic byproducts produced by the combustion of 'herbal' shisha were equivalent or greater than those produced by tobacco shisha. The results of our air quality assessment demonstrated that mean PM2.5 levels and CO content were significantly higher in waterpipe establishments compared to a casino where cigarette smoking was permitted. Nicotine vapour was detected in one of the waterpipe cafés. 'Herbal' shisha products tested contained toxic trace metals and PAHs levels equivalent to, or in excess of, that found in cigarettes. Their mainstream and sidestream smoke emissions contained carcinogens equivalent to, or in excess of, those of tobacco products. The content of the air in the waterpipe cafés tested was potentially hazardous. These data, in aggregate, suggest that smoking 'herbal' shisha may well be dangerous to health. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Modelling NOx emissions of single droplet combustion

NASA Astrophysics Data System (ADS)

Moesl, Klaus G.; Schwing, Joachim E.; Sattelmayer, Thomas

2012-02-01

An approach for modelling and simulation of the generation of nitrogen oxide (NOx) in the gas phase surrounding single burning droplets is presented. Assuming spherical symmetry (no gravity, no forced convection), the governing equations are derived first. Then simplifications are introduced and it is proven that they are appropriate. The influences of the initial droplet diameter, the ambient conditions, and the droplet pre-vapourisation on NOx are investigated. The fuel of choice is n-decane (C10H22) as it resembles kerosene and diesel fuel best, and the complexity of the reaction mechanism is manageable. Combinations of C10H22 mechanisms and well-established NOx kinetics are evaluated in detail and validated for their applicability in the context of this work. The conducted simulations of droplet combustion in an atmosphere of hot exhaust gas show that NOx formation (by mass of fuel) increases linearly with the droplet diameter. There is a trade-off between available oxygen and ambient temperature. Increasing the equivalence ratio of the exhaust gas leads to higher NOx emissions in the very lean regime, but to lower emissions if the equivalence ratio exceeds 0.85. Pre-vapourisation of fuel at ambient conditions becomes beneficial with respect to NOx emissions only if the degree of vapourisation is above a minimum limit. If less fuel is vapourised before ignition, the NOx emissions remain almost unaffected.

Life cycle assessment of switchgrass- and corn stover-derived ethanol-fueled automobiles.

PubMed

Spatari, Sabrina; Zhang, Yimin; MacLean, Heather L

2005-12-15

Utilizing domestically produced cellulose-derived ethanol for the light-duty vehicle fleet can potentially improve the environmental performance and sustainability of the transport and energy sectors of the economy. A life cycle assessment model was developed to examine environmental implications of the production and use of ethanol in automobiles in Ontario, Canada. The results were compared to those of low-sulfur reformulated gasoline (RFG) in a functionally equivalent automobile. Two time frames were evaluated, one near-term (2010), which examines converting a dedicated energy crop (switchgrass) and an agricultural residue (corn stover) to ethanol; and one midterm (2020), which assumes technological improvements in the switchgrass-derived ethanol life cycle. Near-term results show that, compared to a RFG automobile, life cycle greenhouse gas (GHG) emissions are 57% lower for an E85-fueled automobile derived from switchgrass and 65% lower for ethanol from corn stover, on a grams of CO2 equivalent per kilometer basis. Corn stover ethanol exhibits slightly lower life cycle GHG emissions, primarily due to sharing emissions with grain production. Through projected improvements in crop and ethanol yields, results for the mid-term scenario show that GHG emissions could be 25-35% lower than those in 2010 and that, even with anticipated improvements in RFG automobiles, E85 automobiles could still achieve up to 70% lower GHG emissions across the life cycle.

Searching for Lyman-alpha Emitters as a Probe of Cosmic Reionization and Peering Inside Galaxies in the First Two Billion Years

NASA Astrophysics Data System (ADS)

Jung, Intae; Finkelstein, Steven; CANDELS team

2018-01-01

In the reionization era an immediately accessible method for studying the intergalactic medium is to measure the equivalent width distribution of Lyman-alpha emission from galaxies with follow-up spectroscopy. To search for Lyman-alpha emission from galaxies at z ~ 5-8, we perform spectroscopic observations of candidate galaxies from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We utilize data from the Keck DEIMOS (optical) and MOSFIRE (near-infrared) spectrographs, ensuring a comprehensive wavelength coverage of Lyman-alpha emission at z ~ 5-8. We have a total of 1170 object-hours of spectroscopic integration of galaxies at z > 5: 118 galaxies with DEIMOS and 69 galaxies with MOSFIRE. The equivalent width distribution of Lyman-alpha emission is constrained with the number of detected objects from our dataset by constructing detailed simulations of mock emission lines, which consider observational conditions and the photometric redshift probability distribution function. We present our robust measure of the evolution of the Lyman-alpha emission equivalent width distribution at z ~ 5-8.Understanding what drives star-formation quenching in the early universe is a long-standing puzzle. To reveal the hidden relation of quenching with galaxy structural properties, particularly central stellar mass density, we perform the first spatially resolved stellar population study of galaxies at z ~ 4, utilizing the CANDELS imaging data set over the GOODS-S field. We examine 166 photometric-redshift-selected galaxies at 3.5 < z < 4.0 with additional deep K-band survey data from the HAWK-I UDS and GOODS Survey which covers the 4000Å break at these redshifts. We estimate the stellar mass, star formation rate, and dust extinction for galaxy inner and outer regions via spatially resolved spectral energy distribution fitting based on a Markov Chain Monte Carlo algorithm. By comparing specific star formation rates (sSFRs) between inner and outer parts of the galaxies we find that the majority of galaxies with high central mass densities show evidence for a preferentially lower sSFR in their centers than in their outer regions, indicative of reduced sSFRs in their central regions.

Study on feasible technical potential of coal to electricity in china

NASA Astrophysics Data System (ADS)

Jia, Dexiang; Tan, Xiandong

2017-01-01

The control of bulk coal is one of the important work of air pollution control in China’s future. Existing research mainly focuses on the adaptability, economy, construction and renovation plan, and operation optimization of specific energy substitution utilization, and lacks the strategy research of long-term layout of energy substitution utilization in large area. This paper puts forward a technical potential prediction method of coal to electricity based on the thermal equivalent method, which is based on the characteristics of regional coal consumption, and combined with the trend of adaptability and economy of energy substitution utilization. Also, the paper calculates the comprehensive benefit of coal to electricity according to the varieties of energy consumption and pollutant emission level of unit energy consumption in China’s future. The research result shows that the development technical potential of coal to electricity in China is huge, about 1.8 trillion kWh, including distributed electric heating, heat pump and electric heating boiler, mainly located in North China, East China, and Northeast China. The implementation of coal to electricity has remarkable comprehensive benefits in energy conservation and emission reduction, and improvement of energy consumption safety level. Case study shows the rationality of the proposed method.

Quantifying Pollutant Emissions from Office Equipment Phase IReport

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

Maddalena, R.L.; Destaillats, H.; Hodgson, A.T.

2006-12-01

Although office equipment has been a focal point for governmental efforts to promote energy efficiency through programs such as Energy Star, little is known about the relationship between office equipment use and indoor air quality. This report provides results of the first phase (Phase I) of a study in which the primary objective is to measure emissions of organic pollutants and particulate matter from a selected set of office equipment typically used in residential and office environments. The specific aims of the overall research effort are: (1) use screening-level measurements to identify and quantify the concentrations of air pollutants ofmore » interest emitted by major categories of distributed office equipment in a controlled environment; (2) quantify the emissions of air pollutants from generally representative, individual machines within each of the major categories in a controlled chamber environment using well defined protocols; (3) characterize the effects of ageing and use on emissions for individual machines spanning several categories; (4) evaluate the importance of operational factors that can be manipulated to reduce pollutant emissions from office machines; and (5) explore the potential relationship between energy consumption and pollutant emissions for machines performing equivalent tasks. The study includes desktop computers (CPU units), computer monitors, and three categories of desktop printing devices. The printer categories are: (1) printers and multipurpose devices using color inkjet technology; (2) low- to medium output printers and multipurpose devices employing monochrome or color laser technology; and (3) high-output monochrome and color laser printers. The literature review and screening level experiments in Phase 1 were designed to identify substances of toxicological significance for more detailed study. In addition, these screening level measurements indicate the potential relative importance of different categories of office equipment with respect to human exposures. The more detailed studies of the next phase of research (Phase II) are meant to characterize changes in emissions with time and may identify factors that can be modified to reduce emissions. These measurements may identify 'win-win' situations in which low energy consumption machines have lower pollutant emissions. This information will be used to compare machines to determine if some are substantially better than their peers with respect to their emissions of pollutants.« less

Control of GHG emission at the microbial community level.

PubMed

Insam, H; Wett, B

2008-01-01

All organic material eventually is decomposed by microorganisms, and considerable amounts of C and N end up as gaseous metabolites. The emissions of greenhouse relevant gases like carbon dioxide, methane and nitrous oxides largely depend on physico-chemical conditions like substrate quality or the redox potential of the habitat. Manipulating these conditions has a great potential for reducing greenhouse gas emissions. Such options are known from farm and waste management, as well as from wastewater treatment. In this paper examples are given how greenhouse gas production might be reduced by regulating microbial processes. Biogas production from manure, organic wastes, and landfills are given as examples how methanisation may be used to save fossil fuel. Methane oxidation, on the other hand, might alleviate the problem of methane already produced, or the conversion of aerobic wastewater treatment to anaerobic nitrogen elimination through the anaerobic ammonium oxidation process might reduce N2O release to the atmosphere. Changing the diet of ruminants, altering soil water potentials or a change of waste collection systems are other measures that affect microbial activities and that might contribute to a reduction of carbon dioxide equivalents being emitted to the atmosphere.

Aerosol Health Impact Source Attribution Studies with the CMAQ Adjoint Air Quality Model

NASA Astrophysics Data System (ADS)

Turner, M. D.

Fine particulate matter (PM2.5) is an air pollutant consisting of a mixture of solid and liquid particles suspended in the atmosphere. Knowledge of the sources and distributions of PM2.5 is important for many reasons, two of which are that PM2.5 has an adverse effect on human health and also an effect on climate change. Recent studies have suggested that health benefits resulting from a unit decrease in black carbon (BC) are four to nine times larger than benefits resulting from an equivalent change in PM2.5 mass. The goal of this thesis is to quantify the role of emissions from different sectors and different locations in governing the total health impacts, risk, and maximum individual risk of exposure to BC both nationally and regionally in the US. We develop and use the CMAQ adjoint model to quantify the role of emissions from all modeled sectors, times, and locations on premature deaths attributed to exposure to BC. From a national analysis, we find that damages resulting from anthropogenic emissions of BC are strongly correlated with population and premature death. However, we find little correlation between damages and emission magnitude, suggesting that controls on the largest emissions may not be the most efficient means of reducing damages resulting from BC emissions. Rather, the best proxy for locations with damaging BC emissions is locations where premature deaths occur. Onroad diesel and nonroad vehicle emissions are the largest contributors to premature deaths attributed to exposure to BC, while onroad gasoline emissions cause the highest deaths per amount emitted. Additionally, emissions in fall and winter contribute to more premature deaths (and more per amount emitted) than emissions in spring and summer. From a regional analysis, we find that emissions from outside each of six urban areas account for 7% to 27% of the premature deaths attributed to exposure to BC within the region. Within the region encompassing New York City and Philadelphia, reductions in emissions from large industrial combustion sources that are not classified as EGUs (i.e., non-EGU) are estimated to have up to triple the benefits per unit emission of reductions to onroad diesel sectors, and provide similar benefits per unit of reduced emission to that of onroad gasoline emissions in the region. While a majority of vehicle emission controls that regulate PM focus on diesel emissions, our analysis shows the most efficient target for stricter controls is actually onroad gasoline emissions. From an analysis of the health impacts of BC emissions on specific demographic populations, we find that emissions in the southern half of the US tend to disproportionally affect persons with a below high school education and persons below 50% of the poverty level. Analysis of national risk (independent of population and mortality rates) shows that the largest risks are associated with drier climates, due to the increased atmospheric lifetime resulting from less wet removal of aerosols. Lastly, analysis of the impacts of BC emissions on maximum individual risk shows that contributions to maximum individual risk are weakly to strongly correlated with emissions (R2 ranging from 0.23 in the San Joaquin Valley to 0.93 in the Dallas region). Overall, this thesis shows the value of high-resolution, adjoint-based source attribution studies for determining the locations, seasons, and sectors that have the greatest estimated impact on human health in air quality models.

Observation of EX Hydrae with ASCA

NASA Technical Reports Server (NTRS)

Ishida, Manabu; Mukai, Koji; Osborne, Julian P.

1994-01-01

We have observed the intermediate polar EX Hya with Advanced Satellite for Cosmology and Astrophysics (ASCA), and have clearly detected He-like and H-like K alpha emission lines from Mg to Fe. The intensity ratios of these pairs of lines are not compatible with an isothermal plasma, and a temperature distribution can no longer be parameterized by the conventional two emission component model. We have successfully decomposed iron line emission into thermal plasma component and flourescent component. The equivalent width of the flourescent component is approximately 80 eV.

[Factors influencing ammonia volatilization in a winter wheat field with plastic film mulched ridges and unmulched furrows].

PubMed

Shangguan, Yu-Xian; Shi, Ri-Peng; Li, Na; Han, Kun; Li, Hui-Ke; Wang, Lin-Quan

2012-06-01

The objective of this experiment was to quantify ammonia volatilization from a winter wheat field with plastic film mulched-ridges and unmulched-furrows (PMRF). The trial was conducted during the 2010-2011 winter wheat growing season at Yangling, Shaanxi Province. Ammonia volatilization from the soil was measured using the closed-chamber method. The results indicated that NH3 emission losses ranged between (1.66 +/- 0.3) and (3.28 +/- 0.51) kg x hm(-2) in the PMRF treatment. In comparison, the NH3 emission loss was (4.68 +/- 0.35) kg x ha(-1) in the conventional tillage treatment (i. e., smooth soil surface). The PMRF treatment reduced NH3 emissions by 29.8 to 63.8% compared with the conventional treatment. The NH3 emission losses were equivalent to 1.9% of the applied N in the conventional practice treatment. In contrast, the losses were equivalent to only 0.3% to 0.8% of the applied N in the PMRF treatment. Ammonia emissions were greatest during the first two weeks after sowing. Emissions before winter accounted for 82% of total NH3 emission in the conventional practice treatment, but only 49% to 61% of the total NH3 emission in the PMRF treatment. The soil NH4+ -N content and the soil moisture content had direct effects on NH3 emission before winter in the conventional treatment. In thePMRF treatment, the soil NH4+ -N content had a direct effect on NH3 emission before winter, whereas soil surface temperature and soil moisture had indirect effects. Ammonia emissions after the greening stage were mainly influenced by the soil NH4+ -N content. Simulation results indicated that logarithmic functions best described cumulative NH3 emission in the PMRF + high N rate treatment and the conventional treatment. A linear function best described cumulative NH3 emission in the PMRF + low N rate treatment and the unfertilized treatment. In conclusion, the PMRF treatment can significantly reduce N losses from winter wheat fields by changing the spatial-temporal dynamics of soil NH3 volatilization.

Emissions from residential energy use dominate exposure to ambient fine particulate matter in India

NASA Astrophysics Data System (ADS)

Conibear, L.; Butt, E. W.; Knote, C. J.; Arnold, S.; Spracklen, D. V.

2017-12-01

Exposure to ambient particulate matter of less than 2.5 µm in diameter (PM2.5) is a leading cause of disease burden in India. Information on the source contributions to the burden of disease attributable to ambient PM2.5 exposure is critical to support the national and sub-national control of air pollution. Previous studies analysing the contributions of different emission sectors to disease burden in India have been limited by coarse model resolutions and a lack of extensive PM2.5 observations before 2016. We use a regional numerical weather prediction model online-coupled with chemistry, evaluated against extensive surface observations, to make the first high resolution study of the contributions of seven emission sectors to the disease burden associated with ambient PM2.5 exposure in India. We find that residential energy use is the dominant contributing emission sector. Removing air pollution emissions from residential energy use would reduce population-weighted annual mean ambient PM2.5 concentrations by 52%, reducing the number of premature mortalities caused by exposure to ambient PM2.5 by 26%, equivalent to 268,000 (95% uncertainty interval (95UI): 167,000-360,000) lives every year. The smaller fractional reduction in mortality burden is due to the non-linear exposure-response relationship at the high PM2.5 concentrations observed across India and consequently large reductions in emissions are required to reduce the health burden from ambient PM2.5 exposure in India. Keywords: ambient air quality, India, residential energy use, health impact, particulate matter, WRF-Chem

40 CFR 403.6 - National pretreatment standards: Categorical standards.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Control Authority calculating equivalent mass-per-day limitations under paragraph (c)(2) of this section... production shall be estimated using projected production. (4) A Control Authority calculating equivalent... Control Authority convert the limits to equivalent mass limits. The determination to convert concentration...

40 CFR 403.6 - National pretreatment standards: Categorical standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Control Authority calculating equivalent mass-per-day limitations under paragraph (c)(2) of this section... production shall be estimated using projected production. (4) A Control Authority calculating equivalent... Control Authority convert the limits to equivalent mass limits. The determination to convert concentration...

40 CFR 63.322 - Standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... equivalent control device. (2) Route the air-perchloroethylene gas-vapor stream contained within each dry... contained within each dry cleaning machine through a refrigerated condenser or an equivalent control device... cleaning machine drum through a carbon adsorber or equivalent control device immediately before or as the...

40 CFR 63.322 - Standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... equivalent control device. (2) Route the air-perchloroethylene gas-vapor stream contained within each dry... contained within each dry cleaning machine through a refrigerated condenser or an equivalent control device... cleaning machine drum through a carbon adsorber or equivalent control device immediately before or as the...

40 CFR 403.6 - National pretreatment standards: Categorical standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Control Authority calculating equivalent mass-per-day limitations under paragraph (c)(2) of this section... production shall be estimated using projected production. (4) A Control Authority calculating equivalent... Control Authority convert the limits to equivalent mass limits. The determination to convert concentration...

40 CFR 403.6 - National pretreatment standards: Categorical standards.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Control Authority calculating equivalent mass-per-day limitations under paragraph (c)(2) of this section... production shall be estimated using projected production. (4) A Control Authority calculating equivalent... Control Authority convert the limits to equivalent mass limits. The determination to convert concentration...

40 CFR 403.6 - National pretreatment standards: Categorical standards.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Control Authority calculating equivalent mass-per-day limitations under paragraph (c)(2) of this section... production shall be estimated using projected production. (4) A Control Authority calculating equivalent... Control Authority convert the limits to equivalent mass limits. The determination to convert concentration...

Based on optical fiber Michelson interferometer for acoustic emission detection experimental research

NASA Astrophysics Data System (ADS)

Liang, Yijun; Qu, Dandan; Deng, Hu

2013-08-01

A type of Michelson interferometer with two optical fiber loop reflectors acoustic emission sensor is proposed in the article to detect the vibrations produced by ultrasonic waves propagating in a solid body. Two optical fiber loop reflectors are equivalent to the sensing arm and the reference arm instead of traditional Michelson interferometer end reflecter Theoretical analyses indicate that the sensitivity of the system has been remarkably increased because of the decrease of the losses of light energy. The best operating point of optical fiber sensor is fixed by theoretical derivation and simulation of computer, and the signal frequency which is detected by the sensor is the frequency of input signal. PZT (Piezoelectric Ceramic) is powered by signal generator as known ultrasonic source, The Polarization controller is used to make the reflected light interference，The fiber length is changed by adjusting the DC voltage on the PZT with the fiber loop to make the sensor system response that ΔΦ is closed to π/2. the signal basis frequency detected by the sensor is the frequency of the input signal. Then impacts the surface of the marble slab with home-made mechanical acoustic emission source. And detect it. and then the frequency characteristic of acoustic emission signal is obtained by Fourier technique. The experimental results indicate that the system can identify the frequency characteristic of acoustic emission signal, and it can be also used to detect the surface feeble vibration which is generated by ultrasonic waves propagating in material structure.

The impact of biomass energy consumption on pollution: evidence from 80 developed and developing countries.

PubMed

Solarin, Sakiru Adebola; Al-Mulali, Usama; Gan, Gerald Goh Guan; Shahbaz, Muhammad

2018-05-30

The aim of this research is to explore the effect of biomass energy consumption on CO 2 emissions in 80 developed and developing countries. To achieve robustness, the system generalised method of moment was used and several control variables were incorporated into the model including real GDP, fossil fuel consumption, hydroelectricity production, urbanisation, population, foreign direct investment, financial development, institutional quality and the Kyoto protocol. Relying on the classification of the World Bank, the countries were categorised to developed and developing countries. We also used a dynamic common correlated effects estimator. The results consistently show that biomass energy as well as fossil fuel consumption generate more CO 2 emissions. A closer look at the results show that a 100% increase in biomass consumption (tonnes per capita) will increase CO 2 emissions (metric tons per capita) within the range of 2 to 47%. An increase of biomass energy intensity (biomass consumption in tonnes divided by real gross domestic product) of 100% will increase CO 2 emissions (metric tons per capita) within the range of 4 to 47%. An increase of fossil fuel consumption (tonnes of oil equivalent per capita) by 100% will increase CO 2 emissions (metric tons per capita) within the range of 35 to 55%. The results further show that real GDP urbanisation and population increase CO 2 emissions. However, hydroelectricity and institutional quality decrease CO 2 emissions. It is further observed that financial development, foreign direct investment and openness decrease CO 2 emissions in the developed countries, but the opposite results are found for the developing nations. The results also show that the Kyoto Protocol reduces emission and that Environmental Kuznets Curve exists. Among the policy implications of the foregoing results is the necessity of substituting fossil fuels with other types of renewable energy (such as hydropower) rather than biomass energy for reduction of emission to be achieved.