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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Modeling of Particulate Matter Emissions from Agricultural Operations

Bairy, Jnana 1988- 02 October 2013 (has links)
State Air Pollution Regulation Agencies (SAPRAs) issue and enforce permits that limit particulate matter emissions from all sources including layer and broiler facilities, cattle feedyards, dairies, cotton gins, and grain elevators. In this research, a process was developed to determine distances from emitting sources to where the estimated concentrations were less than the National Ambient Air Quality Standards (NAAQS). These distances are a function of emission rates and meteorological conditions. Different protocols were used to develop emission factors for cattle feedyards and layer houses. Dispersion modeling with American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was conducted to determine the emissions of particulate matter. These data were used to determine the distances from the sources to where the concentrations of particulate matter (PM) would be less than the NAAQS. The current air-permitting process requires that concentrations from a source do not exceed the NAAQS at the property line and beyond for the facility to be in compliance with its permit conditions. Emission factors for particulate matter less than 10 micrometers (PM10) were developed for cattle feedyards using a reverse modeling protocol and Tapered Element Oscillating Microbalance (TEOM) sampler data. Corrections were applied to the TEOM measurements to account for TEOM vs. filter-based low-volume (FBLV) sampler bias and over-sampling of PM10 pre-collectors. Invalid concentrations and dust peaks larger than mean ± 3 times the standard deviation were excluded from this study. AERMOD predictions of downwind concentrations at cotton gins were observed for compliance with 24-hour PM10 and PM2.5 NAAQS at property lines. The emissions from three cotton gins were analyzed at 50 m and 100 m distances. TEOM and FBLV samplers were used to collect 24-hour PM10 measurements inside a laying hen house. The distances to the property lines at which the emissions of PM10 were below the 24-hour average PM10 standards were estimated using AERMOD. The results suggested that the special use of the NAAQS for as the property-line concentration not to be exceeded, could be problematic to agriculture. Emission factors that were comparable of published emission factors were obtained in this study. Large distances to property lines were required when minimum flow rate recommendations were not considered. Emission factors that are representative of the emissions in a particular facility are essential; else facilities could be inappropriately regulated.
2

Sustancias tóxicas en emisiones gaseosas de incineradores hospitalarios

Bárcena, René, Gamboa, Nadia 25 September 2017 (has links)
Se estudió las emisiones de material particulado (PM), vapores y gases de chimenea del incinerador del Instituto Nacional de Enfermedades Neoplásicas y se registró la micrometeorolo' gía. Los gases de chimenea fueron recolectados con un muestreador isocinético; los sólidos totales suspendidos, por muestreo pasivo. Los análisis muestran elevados niveles de PM 10, que contiene Pb, Al, Zn y Ca, así como altas concentraciones de benceno y naftaleno en el gas de chimenea. Se observó que la dispersión del PM tiene escala local. / Toxic substances in gaseous emissions from hospital incineratorsThe Nationallnstitute for Neoplastic Diseases incinerator was studied: emissions were sampled and analyzed for particulate matter (PM), stack gases and vapors and the micrometeorology was also registered. Gases were collected with an isokinetic sampler, total suspended solids by passive sampling. Results show high levels of PM10, which contains Pb, Al, Zn and Ca; high levels of benzene and naphthalene in the gas fireplace. Local dispersion of PM was observed,
3

Real-time measurement of on-road fine particulate matter in Atlanta

Papier, Mark Elliot 01 April 2008 (has links)
Particulate matter is increasingly linked to health effects not only for what was previously thought to be just a respiratory problem, but also for the cardiovascular system. Literature not only supports that high particulate matter over long periods of time is correlated to morbidity and mortality due to both cardiovascular and respiratory means, but that high levels of particulate matter, even in short bursts of high concentrations, may be the triggering mechanism for the onset of such problems. Due to automobiles being a prime source of particulate matter, roadway concentrations are often higher than those measured at off-road measurement sites run by various parts of the United States Government. Furthermore, the government run sites are averaged over timescales at a minimum of an hour and at a maximum of a running three-day twenty-four hour length. These are both so long that mesoscale information about the particulate matter, such as short duration high intensity bursts, would be completely removed from the dataset. This study utilizes a real-time portable instrumentation package, which can effectively measure particulate matter concentrations on the roadways of metro Atlanta. Measurements are taken both inside the cabin of a vehicle, which does have an in-cabin filtration system, and on a bicycle ridden along the streets without any form of filtration. These instruments, specifically calibrated handheld particle counters, did indeed find some spikes of particulates above the government s one-hour averages inside the cabin of a vehicle. Arguably more importantly, while riding a bicycle these handheld particle counters also found spikes of particulates approaching six times the amount monitored by the government sites, and several roadway averages that were higher than the off-road averages for the same time.

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