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Air Pollutant Emissions From Natural Gas-Fueled Pumpjack Engines In The Uinta Basin, Seth Lyman
Air Pollutant Emissions From Natural Gas-Fueled Pumpjack Engines In The Uinta Basin, Seth Lyman
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We measured a comprehensive suite of pollutants emitted from 58 natural gas-fueled pumpjack engines in Utah’s Uinta Basin between January and May 2021, with repeat measurements of five engines in January 2022. We documented the emissions composition of several makes and models of commonly used engines, including Ajax E42, E565, DP60, and DP80 engines; Arrow L795, C101, and C106 engines; and GM Vortec.
Utah Wintertime Measurements Of Heavy-Duty Vehicle Nitrogen Oxide Emission Factors, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald, Adam M. Boies
Utah Wintertime Measurements Of Heavy-Duty Vehicle Nitrogen Oxide Emission Factors, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald, Adam M. Boies
Fuel Efficiency Automobile Test Publications
There have only been a few wintertime studies of heavy-duty vehicle (HDV) NOx emissions in the U.S., and while they have observed increased emissions, fleet characterization to identify the cause has been lacking. We have collected wintertime measurements of NOx emission factors from 1,591 HDV at a Utah Port of Entry in December 2020 that includes individual vehicle identification. In general, the NOx emission factors for 2011 & newer chassis model year HDV are significantly higher than 2017 spring measurements from California. The newest chassis model year HDV (2017 - 2021) NOx emission factors are similar …
On-Road Vehicle Emission Measurements And Their Use In Evaluating Emission Control Effectiveness {Presentation}, Gary A. Bishop
On-Road Vehicle Emission Measurements And Their Use In Evaluating Emission Control Effectiveness {Presentation}, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
The Art Of Poetry And Its Place In The History Of The Coordinating Research Councils Real World Emissions Workshop {Poster}, Gary A. Bishop
The Art Of Poetry And Its Place In The History Of The Coordinating Research Councils Real World Emissions Workshop {Poster}, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Emissions, Shawn Urbanski, Susan O'Neill, Amara L. Holder, Sarah Green, Rick L. Graw
Emissions, Shawn Urbanski, Susan O'Neill, Amara L. Holder, Sarah Green, Rick L. Graw
Michigan Tech Publications
This chapter assesses the current state of the science regarding the composition, intensity, and drivers of wildland fire emissions in the USA and Canada. Globally and in the USA wildland fires are a major source of gases and aerosols which have significant air quality impacts and climate interactions. Wildland fire smoke can trigger severe pollution episodes with substantial effects on public health. Fire emissions can degrade air quality at considerable distances downwind, hampering efforts by air regulators to meet air standards. Fires are a major global source of aerosols which affect the climate system by absorbing and scattering radiation and …
On-Road Nox Emissions Evaluation Of The Repair Effectiveness For Recalled Volkswagen Group Light-Duty Diesel Vehicles In The United States, Gary A. Bishop
On-Road Nox Emissions Evaluation Of The Repair Effectiveness For Recalled Volkswagen Group Light-Duty Diesel Vehicles In The United States, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
The admission by the Volkswagen Group in the fall of 2015 that they had duped the United States new vehicle emissions certification testing resulted in perhaps the most expensive violation of U.S. environmental vehicle emission regulations in its history. As part of the subsequent recall of more than 500,000 vehicles in the U.S., owners could sell their vehicles back to the companies or have them repaired. We have used a number of large on-road emission measurement data sets that were routinely collected before and after the recall to evaluate the fuel specific NOx emissions benefit for the vehicles that …
On-Road Remote Sensing Of Automobile Emissions In The Fresno, Ca Area: Spring 2021, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Fresno, Ca Area: Spring 2021, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald
Winter Measurements Of Heavy-Duty Vehicles To Characterize The Cold Temperature Effectiveness Of Selective Catalytic Reductions Catalyst In Controlling Oxide Of Nitrogen Emissions, Gary A. Bishop, Molly J. Haugen, Brian C. Mcdonald
Fuel Efficiency Automobile Test Publications
No abstract provided.
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2020, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Does California’S Emfac2017 Vehicle Emissions Model Under-Predict California Light-Duty Gasoline Vehicle Nox Emissions?, Gary A. Bishop
Does California’S Emfac2017 Vehicle Emissions Model Under-Predict California Light-Duty Gasoline Vehicle Nox Emissions?, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
On-road remote sensing measurements of light and medium-duty gasoline vehicles collected within California’s South Coast Air Basin since 1999 generally fall within the range of observed summer ambient molar NOx/CO measurements collected during morning rush hours. Compared with ambient and on-road emissions, the California Air Resources Board EMFAC model under predicts 2018 gasoline vehicle NOx emission factors by more than a factor of 2.6. Contributing to these differences is that vehicles older than model year 2006 have NOx emission deterioration rates that are up to 4 time’s higher on-road than predicted by the EMFAC model. A …
Strong Temporal Variability In Methane Fluxes From Natural Gas Well Pad Soils, Seth N. Lyman, Huy N. Q. Tran, Marc L. Mansfield, Ric Bowers, Ann Smith
Strong Temporal Variability In Methane Fluxes From Natural Gas Well Pad Soils, Seth N. Lyman, Huy N. Q. Tran, Marc L. Mansfield, Ric Bowers, Ann Smith
Bingham Research Center
We measured methane and carbon dioxide fluxes at natural gas well pad soils and undisturbed soils in the Rocky Mountain and Gulf Coast regions of the United States, including producing and gas storage wells. We collected both short-term (15 min) and multi-day (between 3 and 8), continuous measurements at 47 well pads and two undisturbed locations. Methane fluxes varied by more than an order of magnitude over periods as short as 30 min (e.g., 19–593 mg m−2 h−1 in one instance), and diurnal and seasonal variability was also significant (e.g., spring-to-fall change from 509 to 14174 mg m …
On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2020, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2020, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2019, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2019, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Are Electric Vehicles A Panacea For Reducing Ozone Precursor Emissions?, Gary A. Bishop
Are Electric Vehicles A Panacea For Reducing Ozone Precursor Emissions?, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Vehicle Exhaust Remote Sensing Device Method To Screen Vehicles For Evaporative Running Loss Emissions, Gary A. Bishop, Timothy H. Defries, James A. Sidebottom, James M. Kemper
Vehicle Exhaust Remote Sensing Device Method To Screen Vehicles For Evaporative Running Loss Emissions, Gary A. Bishop, Timothy H. Defries, James A. Sidebottom, James M. Kemper
Fuel Efficiency Automobile Test Publications
Vehicle hydrocarbon (HC) emissions can be emitted from either tailpipe or non-tailpipe locations and understanding their fleet apportionment is important for successful air pollution policy. Vehicles initially misidentified as having elevated tailpipe HC emissions first indicated that roadside exhaust sensors could detect the presence of evaporative HC emissions as increased noise in the HC/carbon dioxide (CO2) correlation measurement. The 90th percentile of the largest residual of the HC/CO2 correlation is defined as a running loss index (RLI) for each measurement. An RLI that is three standard deviations or greater above the instruments noise indicates possible evaporative …
Inspection And Maintenance Evaluation Using Historical U.S. Remote Sensing Measurements, Gary A. Bishop
Inspection And Maintenance Evaluation Using Historical U.S. Remote Sensing Measurements, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Aerial And Ground-Based Optical Gas Imaging Survey Of Uinta Basin Oil And Gas Wells, Seth N. Lyman, Trang Tran, Marc L. Mansfield, Arvind P. Ravikumar
Aerial And Ground-Based Optical Gas Imaging Survey Of Uinta Basin Oil And Gas Wells, Seth N. Lyman, Trang Tran, Marc L. Mansfield, Arvind P. Ravikumar
Bingham Research Center
We deployed a helicopter with an infrared optical gas imaging camera to detect hydrocarbon emissions from 3,428 oil and gas facilities (including 3,225 producing oil and gas well pads) in Utah’s Uinta Basin during winter and spring 2018. We also surveyed 419 of the same well pads from the ground. Winter conditions led to poor contrast between emission plumes and the ground, leading to a detection limit for the aerial survey that was between two and six times worse than a previous summertime survey. Because the ground survey was able to use the camera’s high-sensitivity mode, the rate of detected …
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2018, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Chicago Area: Fall 2018, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Measuring Emissions From The On-Road Vehicle Fleet In West Los Angeles, Gary A. Bishop
Measuring Emissions From The On-Road Vehicle Fleet In West Los Angeles, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Three Decades Of On-Road Mobile Source Emissions Reductions In South Los Angeles, Gary A. Bishop
Three Decades Of On-Road Mobile Source Emissions Reductions In South Los Angeles, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
In May of 2018, the University of Denver repeated on-road optical remote sensing measurements at two locations in Lynwood, CA. Lynwood area vehicle tailpipe emissions were first surveyed in 1989 and 1991 because the area suffered with a large number of carbon monoxide (CO) air quality violations. These new measurements allow for the estimation of fuel specific CO and total hydrocarbon (HC) emissions reductions, changes in the longevity of emission-control components, and the prevalence of high emitters in the current fleet.
Since 1989 CO emissions decreased approximately factors of 10 (120 ± 8 to 12.3 ± 0.2 gCO/kg of fuel) …
Organic Compound Emissions From A Landfarm Used For Oil And Gas Solid Waste Disposal, Seth N. Lyman, Marc L. Mansfield
Organic Compound Emissions From A Landfarm Used For Oil And Gas Solid Waste Disposal, Seth N. Lyman, Marc L. Mansfield
Chemistry and Biochemistry Faculty Publications
Solid or sludgy hydrocarbon waste is a byproduct of oil and gas exploration and production. One commonly-used method of disposing of this waste is landfarming. Landfarming involves spreading hydrocarbon waste on soils, tilling it into the soil, and allowing it to biodegrade. We used a dynamic flux chamber to measure fluxes of methane, a suite of 54 non-methane hydrocarbons, and light alcohols from an active and a remediated landfarm in eastern Utah, U.S.A. Fluxes from the remediated landfarm were not different from a PTFE sheet or from undisturbed soils in the region. Fluxes of methane, total non-methane hydrocarbons, and alcohols …
On-Road Remote Sensing Of Heavy And Medium-Duty Trucks At The Peralta Weigh Station In The South Coast Air Basin: Spring 2017, Molly J. Haugen, Gary A. Bishop
On-Road Remote Sensing Of Heavy And Medium-Duty Trucks At The Peralta Weigh Station In The South Coast Air Basin: Spring 2017, Molly J. Haugen, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
The Story Of Ever Diminishing Vehicle Tailpipe Emissions As Observed In The Chicago, Il Area, Gary A. Bishop, Molly J. Haugen
The Story Of Ever Diminishing Vehicle Tailpipe Emissions As Observed In The Chicago, Il Area, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
The University of Denver has collected on-road fuel specific vehicle emissions measurements in the Chicago area since 1989. This nearly 30 year record illustrates the large reductions in light-duty vehicle tailpipe emissions and the remarkable improvements in emissions control durability to maintain low emissions over increasing periods of time. Since 1989 fuel specific carbon monoxide (CO) emissions have been reduced by an order of magnitude and hydrocarbon (HC) emissions by more than a factor of 20. Nitric oxide (NO) emissions have only been collected since 1997 but have seen reductions of 79%. This has increased the skewness of the emissions …
Evaluation Of Heavy- And Medium-Duty On-Road Vehicle Emissions In California's South Coast Air Basin, Molly J. Haugen, Gary A. Bishop, Arvind Thiruvengadam, Daniel K. Carder
Evaluation Of Heavy- And Medium-Duty On-Road Vehicle Emissions In California's South Coast Air Basin, Molly J. Haugen, Gary A. Bishop, Arvind Thiruvengadam, Daniel K. Carder
Fuel Efficiency Automobile Test Publications
Emission measurements were collected from heavy-duty (HDVs) and medium-duty vehicles (MDVs) at the Peralta weigh station long-term measurement site near Anaheim, CA in 2017. Two Fuel Efficiency Automobile Test units sampled elevated and ground-level exhaust vehicles totaling 2,315 measurements. HDVs (1844 measurements) exhibited historical reductions in fuel specific oxides of nitrogen (NOx) from the 2008 measurements (55%) with increased use of exhaust gas recirculation and selective catalytic reduction systems. However, as these technologies have aged, the in-use benefits have declined. Infrared %opacity measurements of tailpipe soot decreased 14% since 2012 with increased diesel particulate filter (DPF) use, DPF …
On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2017, Gary A. Bishop, Molly J. Haugen
On-Road Remote Sensing Of Automobile Emissions In The Denver Area: Winter 2017, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
No abstract provided.
Revisit Lynwood, Ca: On-Road Remote Sensing Of Automobile Emissions In The Lynwood, Ca: 2018, Gary A. Bishop
Revisit Lynwood, Ca: On-Road Remote Sensing Of Automobile Emissions In The Lynwood, Ca: 2018, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2017, Gary A. Bishop
On-Road Remote Sensing Of Automobile Emissions In The Tulsa Area: Fall 2017, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
No abstract provided.
Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen
Investigate The Durability Of Diesel Engine Emission Controls, Gary A. Bishop, Molly J. Haugen
Fuel Efficiency Automobile Test Publications
No abstract provided.
Evaluation Of Emissions Benefits Of Federal Reformulated Gasoline Versus Conventional Gasoline, Gary A. Bishop, S. Kent Hoekman, Amber Broch
Evaluation Of Emissions Benefits Of Federal Reformulated Gasoline Versus Conventional Gasoline, Gary A. Bishop, S. Kent Hoekman, Amber Broch
Fuel Efficiency Automobile Test Publications
No abstract provided.
Long-Term Fuel-Specific Nox And Particle Emission Trends For In-Use Heavy-Duty Vehicles In California, Molly J. Haugen, Gary A. Bishop
Long-Term Fuel-Specific Nox And Particle Emission Trends For In-Use Heavy-Duty Vehicles In California, Molly J. Haugen, Gary A. Bishop
Fuel Efficiency Automobile Test Publications
Two California heavy-duty fleets have been measured in 2013, 2015 and 2017 using the On-road Heavy-duty Measurement System. The Port of Los Angeles drayage fleet has increased in age by 3.3 model years (4.2 to 7.5 years old) since 2013, with little fleet turnover. Large increases in fuel specific particle emissions (PM) observed in 2015 were reversed in 2017, returning to near 2013 levels, suggesting repairs and or removal of high emitting vehicles. Fuel specific oxides of nitrogen (NOx) emissions of this fleet have increased and NOx after-treatment systems do not appear to perform ideally in this …