Texas, due to its geographical area, population, and economy is home to a variety of industrialized areas that have significant air quality problems. These urban areas are affected by elevated levels of fine particulate matter (PM2.5). The primary objective of this study was to identify and quantify local and regional sources of air pollution affecting the city of Houston, Texas. Positive Matrix Factorization (PMF) techniques were applied to observational datasets from two urban air quality monitoring sites in Houston from 2003 through 2008 in order to apportion sources of pollutants affecting the study region. Data from 68 species for Aldine and 91 for Deer Park were collected, evaluated, and revised to create concentration and uncertainty input files for the PMF2 and EPA PMF (PMF3) source apportionment models. A 11-sources solution for Aldine and 10-sources for Deer Park were identified as the optimal solutions with both models. The dominant contributors of fine particulate matter in these sites were found to be biomass burnings (2%-8.9%), secondary sulfates I (21.3%-7.6%) and II (38.8%-22.2%), crustal dust (8.9%-10.9%), industrial activities (10.9%-4.2%), traffic (23.1%-15.6%), secondary nitrates (4.4%-5.5%), fresh (1%-1.6%) and aged(5.1%-4.6%) sea salt and refineries (1.3%-0.6%), representing a strong case to confirm the high influence of local activities from the industrial area and the ship channel around the Houston channel. Additionally, potential source contribution function (PSCF) and conditional probability function (CPF) analyses were performed to identify local and regional source-rich areas affecting this urban airshed during the study period. Similarly, seasonal variations and patterns of the apportioned sources were also studied in detail.

This work deals with the impact of operating parameters on fine combustion particles formation in the flue gas of biomass combustion device. The research part of the work describes the properties of fine particles, its basic division, impact on human health and the environment. The basic knowledge of the influence of biomass combustion process on fine particles production up to 1 µm in size is summarized. The main part describes the experimental setup for evaluating the size distribution of fine particles. The following section describes the experimental setup with measured results for various combustion parameters in laboratory combustion, automatic boilers, as well as in the manual wood-burning combustion device. The main parameters which were tested were combustion temperature, oxygen amount, type of fuel and geometry of the burned biomass. The impact of individual parameters on the formation of the fine particles is evaluated. The final part of the thesis summarizes the ways in which it is possible to significantly influence the emissions of fine particles by the appropriate choice of combustion operating parameters.

In this study, visibility observation, aerosol sampling, statistical analysis and model regression were conducted to investigate the influence of suspended particle characteristics and pollution sources on visibility and extinction coefficient in Koahsiung metropolitan area. The scene monitored by a digital camera was then proceeded by digital image processing and were then compared with observed atmospheric visibility observation. Meteorological parameters of various weather patterns (including relative humidity, wind direction, wind speed and mixing height ) played important roles on the reduction of visibility in metropolitan area. Synoptic charts were collected over the 1992-1999 period to analyze their influence on ambient air quality. This study revealed that high PM10 concentration and unhealthful PSI index occurred at weather patterns of high pressure outflow style I and circus-sluice of high pressure outflow¡C Regular visibility was observed during the period of November 1998- April 2000. The highest visibility was above 20 km while the lowest visibility was loss than 1 km in Koahsiung metropolitan area. The observed visibility was mainly distribution over the 2-6 km. The visibility below 6 km were about 61.88% of total observation days and poor visibility was usually occurred in winter. Besides, intensive visibility observation was conducted in January and March, 2000. Visibility was observed hourly at Kaohsiung Meteorological Station and Fa-Shin Temple, respectively. Suspended particles were continuously sampled for five hours at Chien-Chen, Sen-Min and Chien-Gin ambient air quality stations. These measurements were conducted to investigate the influence of chemical and physical properties of suspended particle and meteorological parameters on visibility and extinction coefficient in Koahsiung metropolitan area. Receptor model was applied to understand the emission sources of fine particles (PM2.5) and investigate the influence of emission sources on visual air quality. In addition, the determination of visibility by imagine processing was discussed. Visibility observation was coincided with scene monitoring in order to clarify the relationship between image processing and observed visibility. A illumination eigenvalue calculated by picture transfer software was used to correlate with observed visibility. This study revealed that, illumination eigenvalue and observed visibility had strong negative correlation (R=-0.9079) at effective visual range of 5-10 km. Results form single-factor analysis indicated that no significant variation of aerosol particle concentration was observed at three ambient air quality stations. A bi-mode size distribution of aerosol particles was observed for most stations in Koahsiung metropolitan area. The peak aerodynamic diameter of fine and coarse particles was observed at 0.56-1.0

This diploma thesis is devoted to the issues of the formation of fine particles in dependents on the combustion parameters. The first part of thesis is review, which summarized the information about combustion process and about formation of the gaseous products and fine particles inside them which created during combustion process. The main content of thesis is realization of measurements of fine particles from combustion, in several types of the tested combustion devices. Next part is a description of used measurement devices, which used for measurement. Last chapters are focused on evaluation of results from the measurements, comparison of the measurements between themselves and the finding the existence of the dependence of the formation of fine particles on operational parameters of boiler. And all results are evaluated in the conclusion.

Computer simulation using the Discrete Element Method (DEM) has emerged as a powerful tool in studying the behaviour of particulate systems during powder flow and compaction. Contact law between particles is the most important input to the Discrete Element simulation. However, most of the present simulations employ over-simplistic contact laws which cannot capture the real behaviour of particulate systems. For example, plastic yielding, material brittleness, sophisticated particle geometry, surface roughness, and particle adhesion are all vitally important factors affecting the behaviour of particle interactions, but have been largely ignored in most of the DEM simulations. This is because it is very difficult to consider these factors in an analytical contact law which has been the characteristic approach in DEM simulations. This thesis presents a strategy for obtaining the contact laws numerically and a comprehensive study of all these factors using the numerical approach. A numerical method, named as the Material Point Method (MPM) in the literature, is selected and shown to be ideal to study the particle interactions. The method is further developed in this work in order to take into account all the factors listed above. For example, to study the brittle failure during particle impact, Weibull’s theory is incorporated into the material point method; to study the effect of particle adhesion, inter-atomic forces are borrowed from the Molecular Dynamic model and incorporated into the method. These developments themselves represent a major progress in the numerical technique, enabling the method to be applied to a much wider range of problems. The focus of the thesis is however on the contact laws between extremely fine particles. Using the numerical technique as a tool, the entire existing theoretical framework for particle contact is re-examined. It is shown that, whilst the analytical framework is difficult to capture the real particle behaviour, numerical contact laws should be used in its place.

The focus of this master’s thesis is the issue of fine dust particles suspended in the air and their measurement. The thesis explains the basic characteristics of fine particles and the rules, which they follow. The section then examines the health risks of inhaled particles. Next is explained the influence of particles in the air on the environment, the historical development of the air pollution in the Czech Republic and the most important pollutants. After that is described the legislation, which frames the limits for pollutants suspended in the air. In the practical part is described the methods for calculation the geometry of cascade impactor, the design of three-stage impactor and finally the comparison with professional impactor. The designed impactor was then constructed and tested with wood burning stove as a source of particles.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19737号 / 工博第4192号 / 新制||工||1646(附属図書館) / 32773 / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 阿部 竜, 教授 陰山 洋, 教授 田中 庸裕 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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The costs of cleaning fine coal are substantially higher than those of cleaning coarse coal. Therefore, many many coal companies in the U.S. choose to discard fine coal (150 micron x 0) by means of 6-inch diameter hydrocyclones. The cyclone overflows are stored in fine coal impoundments, which create environmental concerns and represent loss of valuable national resources. The major component of the high costs of cleaning fine coal is associated with the difficulty in fine coal dewatering. Therefore, the availability of efficient of fine coal dewatering methods will greatly benefit companies. In the present study, three different novel dewatering aids have been tested. These include Reagents W (RW), Reagent U (RU), and Reagent V (RV). These reagents are designed to increase the contact angles of the coal samples to be dewatered, which should help decrease the Laplace pressure of the water trapped in filter cake and, hence, increase dewatering rate. They were tested on i) the fresh coal samples from Consolidation Coal Corporation's Buchanan Preparation Plant, ii) a composite drill core sample from the Smith Branch Impoundment, Pinnacle Mine Mining Company, and iii) a blend of coals from the Smith Branch Impoundment, thickener underflow, and thickener feed. The coal samples were used initially for laboratory-scale tests using a 2.5-inch diameter Buchner vacuum filter. The results showed that the use of the novel dewatering aids can reduce the cake moisture up to 50% over what can be achieved without using any dewatering aid. The use of the dewatering aids also increased the kinetics of dewatering by up to 6 times, as measured by cake formation times. On the basis of the laboratory test results, pilot-scale continuous vacuum filtration tests were conducted using a 2-feet diameter Peterson vacuum disc filter. The cake moistures obtained in the pilot-scale test work were similar to those obtained in the laboratory tests, while the fast dewatering kinetics observed in the laboratory tests was manifested as higher throughput. It was found that high-shear agitation is essential for achieving low cake moistures and high throughput. / Master of Science