Concentrations of diesel particulate matter (DPM) and polycyclic aromatic hydrocarbons (PAHs) in platinum mine environments are likely to be higher than in ambient air due to the use of diesel machinery in confined environments. PAHs may be present in gaseous or particulate phases each of which have different human health impacts due to their ultimate fate in the body. The sampling of both phases was made possible by means of small, portable denuder sampling devices consisting of two polydimethylsiloxane multi-channel traps connected in series and separated by a quartz fibre filter. Thermal desorption coupled with two dimensional gas chromatography with mass spectrometric detection (TD-GCxGC-ToFMS) was employed to analyse samples from three different platinum mines. The underground environments revealed that PAHs were predominantly found in the gaseous phase with naphthalene and mono-methylated derivatives being detected in the highest concentrations ranging from 0.15 – 8.73 μg.m-3. Similarly higher gas phase PAH loading was found in the Daspoort Tunnel. The particle bound PAHs underground were found in the highest concentrations at the Load Haul Dump (LHD) vehicle exhaust with dominance of fluoranthene and pyrene and concentrations ranged from 0.52-109.60 ng.m-3. This work highlighted the need to characterise both gaseous and particulate phases of PAHs in order to assess occupational exposure and demonstrated the successful application of these portable denuders in the mining environment. / Dissertation (MSc)--University of Pretoria, 2014. / tm2015 / Chemistry / MSc / Unrestricted

Mit einer mobilen Probenahme- bzw. Messeinrichtung untersuchte das Institut für Luft- und Kältetechnik Dresden (ILK) im Auftrag des LfULG diffuse Staubemissionen in einer Bauschuttrecyclinganlage. Neben der mobilen Messung mit dem Partikelmessgerät APS 3321 kamen stationäre Messeinrichtungen (Impaktoren u. a.) am Messort zum Einsatz. Im Ergebnis wurden repräsentative Feinstaub- sowie Quarzstaubimmissionen für eine Bauschuttrecyclinganlage ermittelt. In einem weiteren Schritt wurden die Messergebnisse nachgerechnet. Geprüft wurde, ob mit einer Immissionsprognose nach TA Luft auf Basis von Emissionsfaktoren nach VDI 3790 Blatt 3, ähnliche Ergebnisse ermittelt werden. Anhand der durchgeführten Rechnungen wird eingeschätzt, dass die berechneten Werte in der Regel über den Messergebnissen, aber mit einer akzeptablen Toleranz, liegen. Bei Anpassung der Rechenparameter an die Betriebsbedingungen vor Ort wird eine relativ gute Übereinstimmung erzielt.

In recent decades much effort has gone into reducing particle emissions in the exhaust gases of heavy-duty diesel engines. Engine development has now reached the stage where it is worth to put heavy focus on the contribution of lubricating oil to particulate emissions in order to further reduce these emissions. A literature study demonstrates that the cylinder system is usually the largest source of oil-related particles. Oil consumption in the cylinder can be divided into throw-off effects when inertia forces act on the piston, piston rings and oil; evaporation from hot surfaces; reverse blow-by when gas pressure drives the oil consumption; and top land scraping when oil is scraped off the cylinder liner. The pressure between the compression rings strongly affects the stability and position of the upper compression ring as well as the oil consumption caused by the reverse blow-by. A method to measure the inter-ring pressure was developed and evaluated. The measurements showed that cycle-to-cycle variations were small, but that the inter-ring pressure varied over time. Calculations with AVL Excite Piston and Rings confirmed that ring gap positions can have a major influence on the inter-ring pressure. The measured particle size and number distributions at motoring conditions show interesting and unexpected results. The high number of particles with a diameter of around 100 nm was greatly reduced when the temperature in the diluter was increased. The mean number particle diameter decreased until 10 nm and then became stable independent of further temperature increase. Other authors have found that the small particles (nucleation mode) are reduced and the larger particles (accumulation mode) are more or less unaffected when exhaust gases are heated up and diluted. / QC 20101112

Hazards associated with air pollution motivate the search for technologies capable of monitoring individual exposure to gaseous pollutants and particulate matter (PM). A Low-cost Optical Particle Counter (OPC), costing less than 50 USD, is an example of such technologies. Currently, OPCs are widely used to measure the concentration of particle matter in ambient air. While these low-cost air quality sensors are widely available, the accuracy and precision of these devices is highly uncertain. Consequently, the purpose of this thesis is to present an analytical model of two generic, low-cost OPCs based on the Laws of Conservation of Mass, Momentum, and Energy. These models utilize Mie scattering theory and Computational Fluid Dynamics models to quantify uncertainty and accuracy in low-cost OPCs based first principles. Modeling results indicate that the measurement of forward-scattered light may dramatically increase the accuracy of low-cost OPCs. These results also indicate that careful attention must be placed on the design of sensor flow passages so as to most efficiently transport particles to the scattering volume where they may be detected. A combination of careful attention to photodetector placement in the forward scattering regime as well as efficient transport to the scattering volume may increase low-cost OPC accuracy by magnitudes of order.

El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / This research will focus on proposing a model based on surveys conducted among people of the affected area. The questions were classified by indicators and variables selected to generate solutions to reduce social conflicts, which arise due to the emission of the particulate matter generated in the area before hauling tasks. Particulate matter is produced by hydraulic shovels, which load mineralized material and discharge it to a dump truck in mining operations. This survey was conducted among people who are specifically located in the Huari region. A study of the Social Conflict Monitoring Model (MMCS) tool was executed. It is used for recording, monitoring, and controlling this type of social conflicts, so that mining operations will not be affected in the short or long term. In addition, this model will help in discovering the opinions and/or comments when they are informed on a new method, which decreases generated particulate matter.

Luftverschmutzung ist ein zentrales Thema der Umweltmedizin. Dabei beeinflusst partikuläre Luftverschmutzung entscheidend die Luft, besonders auch in Leipzig. Die Problematik „Feinstaub“ steht aktuell im Fokus von Politik, Rechtssprechung, Presse und Wissenschaft. Zahlreiche Studien belegen die Zusammenhänge zwischen aerosolbelasteter Luft und vielgestaltigen Gesundheitsgefährdungen. Insbesondere das respiratorische System kann durch luftgetragene Partikel gravierende Schädigung erfahren. Lange Zeit wurden ausschließlich die Massekonzentrationen der Partikel untersucht. Jüngere Forschungsbemühungen auf diesem Gebiet konzentrieren sich jedoch verstärkt auf chemische und physikalische Eigenschaften der Partikel. Die vorliegende Arbeit untersucht die Einflüsse von Partikelkonzentrationen auf die respiratorische Gesundheit im prähospitalen Bereich der notfallmedizinischen Versorgung in Leipzig. Es galt hierbei vorrangig die Einflüsse von Anzahl, Oberfläche und Volumen der luftgetragenen Partikel auf die respiratorischen Notfallrisiken zu untersuchen.

Feinstaub kleiner 2,5 Mikrometer (PM2,5) ist ein neuer Parameter zur Beurteilung der Luftqualität. Ziel- und Grenzwerte für PM2,5 wurden mit der Novellierung der EU-Luftqualitätsrichtlinie 2008 zusätzlich zu denen für Feinstaub kleiner 10 Mikrometer (PM10) festgelegt. Die größten sächsischen Quellen für PM2,5 sind Straßenverkehr und Kleinfeuerungsanlagen für feste Brennstoffe. Industrie und Landwirtschaft sind weitere Quellen. Der Anteil von PM2,5 am PM10 ist bei den Jahresmittelwerten stabil. Deshalb können für die Beurteilung der Luftqualität an geringer belasteten Orten auch die bisher gemessenen PM10-Daten mit herangezogen werden. Der ab 2015 geltende Grenzwert für PM2,5 ist in Sachsen bisher nicht überschritten worden. Die erstmals für die ganze Fläche Sachsens modellierte Belastung hat für die Prognosejahre 2015 und 2020 ebenfalls keine Hinweise auf Grenzwertüberschreitungen ergeben. Das nationale Ziel für die Minderung der durchschnittlichen Exposition der Bevölkerung bis 2020 stellt noch einmal höhere Anforderungen an die Luftqualität.

The relative contributions of PM2.5 and ozone precursor emissions to air pollution-related premature mortality modulated by climate change are estimated for the U.S. using sensitivities of air pollutants to precursor emissions and health outcomes for 2001 and 2050. Result suggests that states with high emission rates and significant premature mortality increases induced by PM2.5 will substantially benefit in the future from SO2, anthropogenic NOX and NH3 emissions reductions while states with premature mortality increases induced by O3 will benefit mainly from anthropogenic NOX emissions reduction. Much of the increase in premature mortality expected from climate changeinduced pollutant increases can be offset by targeting a specific precursor emission in most states based on the modeling approach followed here.

Measuring air pollution emissions from agricultural activities is usually difficult because of their large area and variability. Traditional air quality sensors, called point samplers, measure conditions in one location, which may not adequately measure a plume. Remote sensors, instruments that measure pollution along a line rather than at a single point, are better able to measure conditions around large areas. This dissertation reports on four agricultural air emissions studies that used both point and remote sensors for comparison. The methods used to calculate the emissions are based on previous work and are further developed in these studies. In particular, an atmospheric dispersion model was developed and tested that can account for a particle behaving different than the surrounding gas due to gravity and inertia and depositing out of the flow. Particulate matter (PM) emissions values are reported for two agricultural tillage conservation management practices (CMPs)and the corresponding traditional tillage methods in order to determine how well the CMP reduces emissions. In addition, gas-phase ammonia (NH3) emissions for a dairy operation and PM emissions from a feedlot operation are reported. These studies can help us better measure emissions from agricultural operations and understand how much air pollution is being emitted.

Indiana University-Purdue University Indianapolis (IUPUI) / The Electrical capacitance tomography (ECT) method has recently been adapted to obtain tomographic images of the cross section of a diesel particulate filter (DPF). However, a soot mass estimation algorithm is still needed to translate the ECT image pixel data to obtain soot load in the DPF. In this research, we propose an estimation method to quantify the soot load in a DPF through an inverse algorithm that uses the ECT images commonly generated by a back-projection algorithm. The grayscale pixel data generated from ECT is used in a matrix equation to estimate the permittivity distribution of the cross section of the DPF. Since these permittivity data has direct correlation with the soot mass present inside the DPF, a permittivity to soot mass distribution relationship is established first. A numerical estimation algorithm is then developed to compute the soot mass accounting for the mass distribution across the cross-section of the DPF as well as the dimension of the DPF along the exhaust flow direction. Firstly, ANSYS Electronic Desktop software is used to compute the capacitance matrix for different amounts of soot filled in the DPF, furthermore it also analyzed different soot distribution types applied to the DPF. The Analysis helped in constructing the sensitivity matrix which was used in the numerical estimation algorithm. Experimental data have been further used to verify the proposed soot estimation algorithm which compares the estimated values with the actual measured soot mass to validate the performance of the proposed algorithm.