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Atmospheric ammonia (NH₃(g)) poses an environmental concern mainly due its ability to form fine particulate matter (PM2.5 with a diameter smaller than 2.5 micrometers) in the form of ammonium nitrate (NH₄NO₃) and ammonium sulfate ([NH₄]₂SO₄). These forms of PM2.5 may reduce visibility, contribute to eutrophication through deposition, and be detrimental to human health through inhalation. A more complete understanding of ammonia emissions may bring significant PM2.5 reductions within grasp. According to recent studies, one of the largest contributors to atmospheric ammonia is dairy cattle excreta. In this study, seven lactating Holstein cows were subjected to four feeding trials with diets containing 14.5, 15.5, 17, and 18% crude protein (CP). The first objective was to determine the effect of protein content/intake on ammonia fluxes to the atmosphere from each stage of manure handling at a flush dairy. The second objective was to examine the effect of manure handling itself on ammonia fluxes. We examined four different stages of manure handling: 1. Fresh mixture of urine and feces to represent what may be scraped from a barn floor 2. Diluted mixture of urine and feces to represent what is flushed from a barn floor 3. Solids portion of a diluted mixture of urine and feces to represent what is retained by a solids separator at a dairy 4. Liquid portion of a diluted mixture of urine and feces to represent the permeate from a solids separator at a dairy Ammonia fluxes from scraped manure began low and rose to higher fluxes and peaked at an average of 25 hours after mixing urine and feces. Fluxes from flushed manure showed the same behavior. The average pH values for the scraped and flushed manure were relatively low at 6.87±0.17 and 7.05±0.13, respectively, and unfavorable toward ammonia versus ammonium. Fluxes from the separated solids and liquid manure, whose pH values were higher at 8.70±0.30 and 8.55±0.19, respectively, peaked almost immediately. For a time period of 18 hours after beginning flux measurements from the separated liquid manure, fluxes stayed relatively constant. Compared to hours 0-9, fluxes from the separated solids manure decreased 11% in hours 9-18. These results indicate that ammonia fluxes from the scraped and flushed manure were initially limited by the relatively low pH of the slurries, until they aged and released carbon dioxide, after which fluxes became controlled by temperature. Fluxes from the separated solids and liquid manure, however, were temperature-controlled from the start, as this manure had already undergone some aging and the initial pH was more favorable to ammonia loss. Multivariable regressions predicting the mass of ammonia lost to the atmosphere as a function of total ammoniacal nitrogen (TAN) and temperature (T) show that fluxes from the scraped and flushed manure are very sensitive to temperature compared to the separated solids and liquid manure. The same regressions show that ammonia fluxes from the separated solids and liquid manure are predicted well by TAN and T (R² = 0.906 and 0.812, respectively), indicating that dietary protein manipulation, which affects TAN content of the manure, may have a greater effect in this stage of handling. Regressions predicting the mass of ammonia lost to the atmosphere as a function of crude protein intake show crude protein intake is a poor predictor of the overall ammonia flux from a flush dairy. Low correlation coefficients from these regressions are likely a result of cow-to-cow variability in the effect of crude protein intake on ammonia emissions. Significant reductions in ammonia fluxes are possible; however, they will require new regulations on manure handling at flush dairies or incentives for flush dairies to pursue alternate means of manure handling with low emissions. Dairies can begin attacking the problem of excessive emissions by lowering the dietary protein content for older cows to reduce the mass of TAN excreted in their manure, thereby reducing ammonia fluxes in accordance with Henry's law. Once manure is excreted on the barn floor, dairies must encourage mixing between urine and feces and use the natural acidity of the feces in delaying emissions by converting aqueous ammonia in the urine to ammonium. Dairies can achieve well-mixed slurries by manually mixing the manure or with a sloped floor, channeling urine and feces to a common area. Covering holding tanks containing flushed manure to minimize CO₂ stripping and a rise in pH is one measure that may reduce ammonia fluxes. Finally, requiring nitrification or nitrification and denitrification in on-site storage tanks will biologically convert ammonia to nitrate or nitrogen gas, respectively, reducing fluxes from the separated liquid manure. Although burdensome to dairies, these measures would drastically reduce ammonia emissions from flush dairies. Regulatory agencies may choose to ignore the separated solids manure when considering strategies to reduce ammonia emissions, since ammonia volatilization becomes limited by aqueous ammonia in the first 18 hours following separation. / Master of Science

An extended air sampling program was conducted at an electric-arc secondary steel manufacturing facility using the HI-VOLUME Sampler reference method for suspended particulates. A wind recording device was installed at the facility to provide a continuous record of wind data for correlation with the particulate concentrations collected. Weather data obtained from the National Weather Service were also used. A relationship between wind direction and speed with the levels of particulate matter collected was found indicating areas of significant pollution sources. Wind-pollution roses were constructed showing the frequency distribution of the wind during periods when particulate concentrations were above and below the national ambient air standards. These roses were compared with the atmospheric stability classes for each of those periods. Log-probability plots were constructed for each sampling point and an exponential relationship was found between mean concentrations at each sampler and each sampler's distance from the source. Using this relationship, an estimated emission rate for the facility was calculated. A background level for the area in the vicinity of the facility was found. Some conclusions were that the mean level of concentration decreased exponentially with distance from the source and that the estimated emission rate for the facility was below the maximum allowable by the State Air Pollution Control Board. It was also concluded that, in long term sampling, wind characteristics showed a positive relationship with particulate concentrations. The most significant conclusion was that the emission activity at the steel facility had minimal effect on a sampler located 1,000 yards away. / Master of Science

Construction and Demolition (C&D) processing and recycling facilities accept waste materials that are generated during construction and demolition activities. The processing facility sorts, processes, and transfers the material to another operation. A consequence of these processes is the generation of particulate matter.This study involved quantifying and qualifying airborne particulates at three C&D processing facilities. Active stationary particulate sampling devices were employed to quantify the particle sizes of interest. Results were compared to United States Environmental Protection Agency (EPA) National Ambient Air Quality Standards(NAAQS) and United States Occupational Safety and Health Administration (OSHA)standards.The results from this study are not valid for determination of compliance with NAAQS or OSHA standards. However, the data indicate that C&D processing facilities may exceed current NAAQS at certain locations, but do not exceed OSHA standards. These results can be used by the industry as an engineering tool to reduce airborne particulate levels during normal operations of C&D facilities.

Particulate emissions from diesel engines have been a key issue for diesel engine developers in recent decades. Their work has succeeded in reducing the exhaust particles from the combustion of fuel, which has led to increasing interest in the contribution of particulates from lubrication oil. When discussing oil-related particulate emissions, hydrocarbon particles are customarily referred to. This thesis uses a broader definition, in which oil-related particulate emissions are modelled not only by the hydrocarbons, but also include the ash, carbons, and sulphate oil particulate emissions. The model developed in the project uses input data as oil consumption and oil ash content combined with tuning parameters, such as the oil ash transfer rate (ash emissions divided by oil consumption and oil ash content). Controlled engine tests have been performed to verify assumptions and fill knowledge gaps. The model can be applied to a variety of diesel engines, although the tuning factors might have to be reset. For example, introducing diesel particulate filters would dramatically reduce the oil ash emissions, since oil ash would accumulate in the filter. Oil consumption has played a central role in the present research. The modelling results indicate that special attention should be paid to oil consumption under running conditions with a low in-cylinder temperature, since the oil survival rate is high there. Under low-load and motoring conditions, hydrocarbons proved to be the main contributor to oil-related particulate emissions. At high engine load, oil ash emissions were the largest contributor to oil-related particulate emissions. / QC 20101103

Burning joss paper and incense is a significant Taoist ceremonial practice in Asian countries such as Taiwan and China. The burning of joss paper has been demonstrated to significantly create particulate matters (PM) and to cause air pollution problems. PM in the atmosphere is among the primary air pollutants, and their sources are factories, vehicles, construction fields, combustion, vehicle exhaust dust, and aerosols derived from photochemical reactions. Numerous sources of environmental PM exist. Thus, the ability to rapidly determine the particulate type and source to adjust the controls and develop policies is an important issue for air quality management. This dissertation consists of two parts on the particulate emission control and characteristic identification. In the first part, we study investigates feasible options of air pollution control devices (APCD) for joss paper furnaces in temples, and used a 40 kg/hr joss paper furnace for testing. This paper examined particulate removal efficiencies of two options: a bag house (capacity 30 m3/min at 108 ¢J) and a wet scrubber (capacity 40 m3/min at 150 ¢J). The results indicate that PM in the diluted flue gas at the bag-house inlet were 76.6 ¡Ó 32.7 mg/Nm3 (average ¡Ó standard deviation), and those at the outlet of the bag-house could be reduced to as low as 0.55 ¡Ó 1.28 mg/Nm3. An average PM removal efficiency of 99.3 % could be obtained with a filtration speed of approximately 2.0 m/min evaluated at 108 ¢J. The wet scrubber removed approximately 70 % of PM, with scrubbing intensities higher than 4.0 L/m2.s across the scrubber cross-section. For the duration of the experiment, no visual white smoke (water mist) was observed at the exit of the wet scrubber with a combustion rate of 16 kg/hr of joss paper, and the scrubbing water temperature was automatically sustained at lower than 61 ¢J. The study concluded that both bag filtration and wet scrubbing are suitable techniques to control particulate emission from joss paper furnaces in Taiwanese temples. The bag filtration technique, while achieving higher efficiencies than the wet scrubbing technique, requires more space and cost. Examinations of bottom and fly ashes of combusted joss paper with X-ray diffraction (XRD) revealed the presence of calcium oxide in the fly ash, while certain metals were found in the bottom ash. The second part aimed at the investigates surface characteristics of airborne PM sampled from air pollution control devices of a number of industrial operations. The PM sources selected for this study comprise the following operations or processes: a coke oven, iron ore sintering furnace, blast furnace, and basic oxygen furnace from an integrated steelmaking plant; electric arc furnaces of two secondary steelmaking plants; a municipal solids waste incinerator; two oil-fired boilers; and a coal-fired power plant boiler. The collected PM samples were analyzed using a scanning electronic microscope (SEM) and energy-dispersive X-ray spectroscope (EDS) to determine their chemical composition and surface characteristics. Results for each PM sample regarding size, surface characteristics, and chemical compositions can be used to trace the related emission industrial sources.

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Diesel particulate matter (PM) produced from Ultra Low Sulfur Diesel (ULSD), Soy-derived B20 and Animal fat-derived B20 was collected at two engine operating conditions. Gravimetric analysis showed the PM emissions to depend on both fuel and engine operating condition. B20 fuels exhibited higher PM emissions at low load conditions, but lower PM emissions under high load conditions. The differences between the operating conditions were less significant for B20 fuels than for ULSD. Elemental Carbon analysis revealed the B20 PM to contain greater proportions of organic carbon, which may improve diesel particulate filter (DPF) regeneration. Finally, TEM images showed considerable differences between ULSD and B20 soot at low engine loads. The B20 soot displayed a more disordered arrangement of graphene layers. At higher loads, the differences are subtle, but the B20 PM still displayed a more amorphous structure. There was little difference between the Soy and Animal fat-derived B20 soot.

Diesel particulate matter (PM) produced from Ultra Low Sulfur Diesel (ULSD), Soy-derived B20 and Animal fat-derived B20 was collected at two engine operating conditions. Gravimetric analysis showed the PM emissions to depend on both fuel and engine operating condition. B20 fuels exhibited higher PM emissions at low load conditions, but lower PM emissions under high load conditions. The differences between the operating conditions were less significant for B20 fuels than for ULSD. Elemental Carbon analysis revealed the B20 PM to contain greater proportions of organic carbon, which may improve diesel particulate filter (DPF) regeneration. Finally, TEM images showed considerable differences between ULSD and B20 soot at low engine loads. The B20 soot displayed a more disordered arrangement of graphene layers. At higher loads, the differences are subtle, but the B20 PM still displayed a more amorphous structure. There was little difference between the Soy and Animal fat-derived B20 soot.

This research investigates the difference between indoor and outdoor residential fine particulate matter (PM2.5) and explores the feasibility of predicting residential PM2.5 infiltration for use in exposure assessments. Data were compiled from a previous study conducted in Seattle, Washington, USA and a new monitoring campaign was conducted in Victoria, British Columbia, Canada. Infiltration factors were then calculated from the indoor and outdoor monitoring data using a recursive mass balance model. A geographic information system (GIS) was created to collect data that could be used to predict residential PM2.5 infiltration. Spatial property assessment data (SPAD) were collected and formatted for both study areas, which provided detailed information on housing characteristics. Regression models were created based on SPAD and different meteorological and temporal variables. Results indicate that indoor PM2.5 is poorly correlated to outdoor PM2.5 due to indoor sources and significant variations in residential infiltration. A model based on a heating and non-heating season, and information on specific housing characteristics from SPAD was able to predict a large portion of the variation within residential infiltration. Such models hold promise for improving exposure assessment for ambient PM2.5.