On-road hydrocarbon remote sensing in the Denver area

Zhang, Yi; Stedman, Donald H.; Bishop, Gary A.; Guenther, Paul L.; Beaton, Stuart P.; Peterson, James E.

doi:10.1021/es00046a018

Cited by 33 publications

(23 citation statements)

References 3 publications

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“…Furthermore, neither the fraction of high emitters nor tampering rates differed much regardless of whether or not vehicles were in states where monopolistic or competitive firms supplied inspections. Similar results appear in other studies (Lawson, 1993;Zhang et al, 1993Zhang et al, , 1995.…”

Section: Ill Traditional Iandm Programssupporting

confidence: 92%

Using Inspection and Maintenance Programs to Regulate Vehicle Emissions

Hubbard

1997

Contemporary Economic Policy

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Policymakers have hoped that vehicle inspection and maintenance programs would generate air quality improvements at low cost. Existing programs have been unsuccessful because they have failed to provide consumers with incentives to maintain their vehicles so as to have low in-use emissions. This paper examines the reasons why existing inspection and maintenance programs have failed and investigates how they might be improved. Copyright 1997 Western Economic Association International.

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Section: Ill Traditional Iandm Programssupporting

confidence: 92%

Using Inspection and Maintenance Programs to Regulate Vehicle Emissions

Hubbard

1997

Contemporary Economic Policy

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“…Our high CO emissions did not always correlate with high hydrocarbon emissions. While we do not know the exact cause of this, this effect has been seen in other vehicle studies with a variety of explanations (Beaton et al, 1992;Zhang et al, 1995). While the gaseous pollutants were not significantly reduced post-service, the fleet's total particulate emissions did decrease significantly, and we refer to Jayarathne et al 2016for a detailed comparison.…”

Section: Motorcycle Emissionsmentioning

confidence: 72%

“…Vehicle EFs are commonly obtained from bulk exhaust measurements (USEPA, 2015) and the International Vehicle Emissions (IVEs) model specifically generates EF for mobile sources in the developing world (Shrestha et al, 2013). However, the detailed source chemistry (e.g., specific air toxics) is poorly known, especially for the developing world, as most studies focus only on CO, NO x , PM 2.5 , and a few hydrocarbons or total VOC in developed countries (e.g., Zhang et al, 1993;Pang et al, 2014).…”

Section: Motorcycles and Scootersmentioning

confidence: 99%

Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of trace gases and light-absorbing carbon from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

et al. 2016

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Abstract. The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) campaign took place in and around the Kathmandu Valley and in the Indo-Gangetic Plain (IGP) of southern Nepal during April 2015. The source characterization phase targeted numerous important but undersampled (and often inefficient) combustion sources that are widespread in the developing world such as cooking with a variety of stoves and solid fuels, brick kilns, open burning of municipal solid waste (a.k.a. trash or garbage burning), crop residue burning, generators, irrigation pumps, and motorcycles. NAMaSTE produced the first, or rare, measurements of aerosol optical properties, aerosol mass, and detailed trace gas chemistry for the emissions from many of the sources. This paper reports the trace gas and aerosol measurements obtained by Fourier transform infrared (FTIR) spectroscopy, whole-air sampling (WAS), and photoacoustic extinctiometers (PAX; 405 and 870 nm) based on field work with a moveable lab sampling authentic sources. The primary aerosol optical properties reported include emission factors (EFs) for scattering and absorption coefficients (EF Bscat, EF Babs, in m2 kg−1 fuel burned), single scattering albedos (SSAs), and absorption Ångström exponents (AAEs). From these data we estimate black and brown carbon (BC, BrC) emission factors (g kg−1 fuel burned). The trace gas measurements provide EFs (g kg−1) for CO2, CO, CH4, selected non-methane hydrocarbons up to C10, a large suite of oxygenated organic compounds, NH3, HCN, NOx, SO2, HCl, HF, etc. (up to ∼ 80 gases in all). The emissions varied significantly by source, and light absorption by both BrC and BC was important for many sources. The AAE for dung-fuel cooking fires (4.63 ± 0.68) was significantly higher than for wood-fuel cooking fires (3.01 ± 0.10). Dung-fuel cooking fires also emitted high levels of NH3 (3.00 ± 1.33 g kg−1), organic acids (7.66 ± 6.90 g kg−1), and HCN (2.01 ± 1.25 g kg−1), where the latter could contribute to satellite observations of high levels of HCN in the lower stratosphere above the Asian monsoon. HCN was also emitted in significant quantities by several non-biomass burning sources. BTEX compounds (benzene, toluene, ethylbenzene, xylenes) were major emissions from both dung- (∼ 4.5 g kg−1) and wood-fuel (∼ 1.5 g kg−1) cooking fires, and a simple method to estimate indoor exposure to the many measured important air toxics is described. Biogas emerged as the cleanest cooking technology of approximately a dozen stove–fuel combinations measured. Crop residue burning produced relatively high emissions of oxygenated organic compounds (∼ 12 g kg−1) and SO2 (2.54 ± 1.09 g kg−1). Two brick kilns co-firing different amounts of biomass with coal as the primary fuel produced contrasting results. A zigzag kiln burning mostly coal at high efficiency produced larger amounts of BC, HF, HCl, and NOx, with the halogenated emissions likely coming from the clay. The clamp kiln (with relatively more biomass fuel) produced much greater quantities of most individual organic gases, about twice as much BrC, and significantly more known and likely organic aerosol precursors. Both kilns were significant SO2 sources with their emission factors averaging 12.8 ± 0.2 g kg−1. Mixed-garbage burning produced significantly more BC (3.3 ± 3.88 g kg−1) and BTEX (∼ 4.5 g kg−1) emissions than in previous measurements. For all fossil fuel sources, diesel burned more efficiently than gasoline but produced larger NOx and aerosol emission factors. Among the least efficient sources sampled were gasoline-fueled motorcycles during start-up and idling for which the CO EF was on the order of ∼ 700 g kg−1 – or about 10 times that of a typical biomass fire. Minor motorcycle servicing led to minimal if any reduction in gaseous pollutants but reduced particulate emissions, as detailed in a companion paper (Jayarathne et al., 2016). A small gasoline-powered generator and an “insect repellent fire” were also among the sources with the highest emission factors for pollutants. These measurements begin to address the critical data gap for these important, undersampled sources, but due to their diversity and abundance, more work is needed.

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“…While operating fuel-rich, emissions of CO and VOC increase dramatically. Remote sensing studies also show that exhaust HC concentrations are high under coasting or braking conditions (7), although fuel throughput is low under light-load operating conditions.…”

Section: Introductionmentioning

confidence: 99%

Effects of Vehicle Speed and Engine Load on Motor Vehicle Emissions

Kean

Harley

Kendall

2003

Environ. Sci. Technol.

144

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Laboratory studies have provided a foundation of knowledge regarding vehicle emissions, but questions remain regarding the relationship between on-road vehicle emissions and changes in vehicle speed and engine load that occur as driving conditions change. Light-duty vehicle emissions of CO, NO x , and NMHC were quantified as functions of vehicle speed and engine load in a California highway tunnel for downhill and uphill traffic on a ∼4% grade. Emissions were measured throughout the day; average speed decreased inside the tunnel as traffic volume increased. Emissions of CO were typically 16-34 g L -1 (i.e., grams of CO emitted per liter of gasoline consumed) during downhill driving and ranged from 27 to 75 g L -1 during uphill driving. Downhill driving and moderate-speed uphill driving resulted in similar CO emission factors. The factor of 2 increase in CO emissions observed during higherspeed uphill driving is likely evidence of enriched engine fuel/ air ratios; this was unexpected because uphill driving observed in this study occurred at moderate engine loads within the range experienced during the city driving cycle of the U.S. emissions certification test. Emissions of NO x (as NO 2 ) were typically 1.1-3.3 g L -1 for downhill driving and varied between 3.8 and 5.3 g L -1 for uphill driving. Unlike observations for CO, all uphill driving conditions resulted in higher NO x emission factors as compared to downhill driving. NO x emissions increased with vehicle speed for uphill driving but not as strongly as CO emissions. Emissions of CO and NO x are functions of both vehicle speed and specific power; neither parameter alone captures all the relevant effects on emissions. In contrast to results for CO and NO x reported here and results for NMHC reported previously by Pierson et al. (Atmos. Environ. 1996, 30, 2233-2256, emissions of NMHC per unit of fuel burned for downhill driving were over 3 times greater than NMHC emissions for uphill driving. Emission rates of CO and NO x varied more with driving conditions when expressed per unit distance traveled rather than per unit fuel burned while NMHC emission rates normalized to distance traveled were approximately constant for uphill versus downhill driving during peak traffic periods.

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On-road hydrocarbon remote sensing in the Denver area

Cited by 33 publications

References 3 publications

Using Inspection and Maintenance Programs to Regulate Vehicle Emissions

Using Inspection and Maintenance Programs to Regulate Vehicle Emissions

Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): emissions of trace gases and light-absorbing carbon from wood and dung cooking fires, garbage and crop residue burning, brick kilns, and other sources

Effects of Vehicle Speed and Engine Load on Motor Vehicle Emissions

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