Goal of this dissertation is introduce the problem of small dust particles present in the gaseous products of combustion. Further I´m looking technologies cyclone and an electrostatic filter to capture small particles and comparing the effectiveness of separability. Dissertation is concluded by designed cyclone and an electrostatic filter.

Thesis are focus for detailed description of fine solid particulates which are product from flue gas. Introduction type of Technologies for capture fine solid particulates. Calculation of electrostatic separator for specific coal and wood boiler.

The thesis is devoted to assessing the concept of a new solution to the sliding contact in electrical machines. The work is focused mainly on the issue of collector engines, which are almost exclusively used in electric hand tools. Much of the work is devoted to angle grinders, which are usually used in extreme conditions and demands for seamless operation are enormous. In order partial insight into the problems in the introduction are studied phenomena acting on the sliding contact, wear and durability. Then further materials and diagnostic methods for increasing the transfer efficiency brush - commutator brush - ring. The following sections of this thesis is also considered a proposal innovated brush along with the practical verification and evaluation of the suitability of the use of innovative sliding contact.

No description available.

An investigation into the light scattering properties of Saharan dust grains is presented. An electrodynamic trap has been used to levitate single dust particles. By adjusting the trap parameters, partial randomisation of the particle orientation has been introduced. While levitated, the particles were illuminated by a laser, and a rotating half-wave retarder enabled selection of vertically or horizontally polarized incident light. A laser diffractometer and linear photodiode array have been used to measure intensity at scattering angles between 0.5° and 177°. Combining these measurements with Fraunhofer diffraction as calculated for a range of appropriately-sized apertures allows the calculation of the phase function and degree of linear polarization. The phase functions and degree of linear polarisation for four case study particles are presented - the phase functions are found to be featureless across most of the scattering region, with none of the halo features or rainbow peaks associated with regularly shaped particles such as hexagonal columns or spheres. Particle models comprised of large numbers of facets have been constructed to resemble the levitated particles. Utilizing Gaussian random sphere methods, increasing levels of roughness have been added to the surfaces of these models. A Geometric Optics model and a related model, Ray Tracing with Diffraction on Facets, have been modified to calculate scattering on these particle reconstructions. Scattering calculations were performed on each of these reconstructions using a range of refractive indices and two rotation regimes – one where the orientations of the reconstructed particle were limited to match those observed when the particle was levitated, and one where the orientation was not limited. Qualitative comparisons are performed on the phase functions and degree of linear polarization, where it is observed that the addition of roughness to the modelled spheroids causes the computed phase functions to increasingly resemble those from the levitated particles. Limiting the orientation of the particles does not affect the scattering noticeably. The addition of a very small absorption coefficient does not change the comparisons considerably. As the absorption coefficient is increased, however, the quality of the comparisons decreases rapidly in all cases but one. The phase functions are quantitatively compared using RMS errors, and further comparison is performed using the asymmetry parameter.

In this diploma thesis I focus on poultry farms, as a source of dust particles, which are taken from the breeding establishment to the surroundings of poultry breeding. The first theoretical part of the thesis is focused on dust, dust particles and their sources, as well as on housing of poultry and on BAT technology. These particles can be dangerous not only for the animals but also for the staff working in the vicinity of the farm animals. In the second, practical part of the thesis, I focus on the measurement of dust particles PM10 using the DUST TRUK II measuring instrument in a selected broiler breeding facility, as well as on the processing of measurement results and comparison with hygienic regulations and already measured values.

Aerosol particles interact with sunlight through scattering and absorption and have therefore a direct radiative effect. Hygroscopic aerosol particles take up water and are able to grow in size below 100% relative humidity, which involves the change of optical properties and the direct radiative effect. The change of aerosol optical properties for aerosol mixtures under humidification is presently not well understood, especially for the largest particle sources worldwide. The present PhD-thesis quantifies wavelength- and humidity-dependent aerosol optical properties for a mixture of Saharan mineral dust and marine aerosol. For quantification, an aerosol model was developed, which based on in-situ measurements of microphysical and optical properties at Cape Verde. With this model, aerosol optical properties were calculated from the dry state up to 90% relative humidity. To validate the model, a measure of the total extenuated light from particles under ambient conditions was used. Finally, the humidity dependence of aerosol optical properties for marine aerosol, Saharan dust aerosol, and a mixture of both species was described by two empirical equations. With the wavelength of the incident visible solar radiation, relative humidity, and dry dust volume fraction, the humidity dependence of optical properties can be calculated from tabulated values. To calculate radiative effects, aerosol optical properties were used as input parameters for global circulation models including radiative transfer. Due to the complexity of aerosol related processes, they have been treated implicitly, meaning in parameterized form. For modelling purposes, the present PhD-thesis provides a solution to include humidity effects of aerosol optical properties. / Aerosolpartikel wechselwirken durch Streu- und Absorptionsprozesse mit der einfallenden Sonnenstrahlung und haben somit einen direkten Strahlungseffekt. Bei relativen Feuchten bis 100% können Aerosolpartikel aufquellen und somit ihre Größe ändern. Im Zuge des Aufquellens, ändern sich die optischen Eigenschaften und somit auch der direkte Strahlungseffekt der Aerosolpartikel. Speziell für Mischungen von verschiedenen Aerosolspezies ist die Änderung der optischen Eigenschaften des Aerosols durch Feuchte Einfuss noch nicht ausreichend verstanden. Gegenstand der vorliegenden Arbeit ist daher die Quantifizierung der wellenlängen- und feuchteabhängigen optischen Eigenschaften einer Mischung von Saharastaub- und marinen Aerosol. Die zur Quantifizierung notwendigen Daten wurden im Rahmen einer Feldmessung von mikrophysikalischen- und optischen Aerosol-Eigenschaften auf den Kapverdischen Inseln gesammelt. Auf Grundlage dieser Messungen wurde ein Aerosol-Modell entwickelt. Dieses Modell wurde daraufhin verwendet, um Berechnungen von optischen Aerosol-Eigenschaften bei relativen Feuchten bis 90% durchzuführen. Eine Messung der Lichtschwächung durch Aerosolpartikel unter Umgebungsbedingungen wurde verwandt, um das Modell bei Umgebungsfeuchten zu validieren. Die Wellenlängen- und Feuchteabhängigkeit der optischen Eigenschaften des Aerosols wurde parametrisiert und konnte anhand von zwei Parametergleichungen bestimmt werden. Unter Benutzung von tabellierten Werten und der Wellenlänge des einfallenden sichtbaren Sonnenlichtes, der relativen Feuchte, sowie der Staubvolumenfraktion, kann die Feuchteabhängigkeit von wichtigen Aerosol-optischen Eigenschaften für Saharastaub, marinen Aerosol und einer Mischung aus beiden Komponenten bestimmt werden. Globale Zirkulationsmodelle, die auch eine Berechnung von Strahlungseffekten durch Aerosolpartikel beinhalten, nutzen Aerosol-optische Eigenschaften als Eingabeparameter. Durch zunehmende Komplexitiät zur Beschreibung von Wechselwirkungen in der Atmosphäre, sind einfache Parametrisierungen unabdingbar. Die vorliegende Arbeit liefert daher einen wichtigen Beitrag für die Modellierung von Strahlungseffekten durch Aerosolpartikel und somit zum Verständnis des Strahlungshaushaltes der Erde.

Nowadays much attention is paid to air pollution in the world. Effective and suitable management of atmosphere protection is very important, because climate change, human health and survival of biodiversity depends on it. For these reasons atmosphere protection management should get our special interest. The aim of this work is to analyse the structure of atmosphere protection in Lithuania and to provide proposals on how to improve it. This work also suggests how to improve the policy of atmosphere protection and ensure appropriate air quality in Lithuania. This master‘s work consists of four parts, which are designated to analyse the structure of atmosphere protection management and cooperation between institutions, to make systematic analysis of atmosphere protection laws and examine possible inaccuracies, to find inaccuracies in institutional, legal and financial systems, which are related to the management of atmosphere protection and to sugest some improvements on how to improve the structure of atmosphere protection management and the policy of atmosphere protection. Implementing the tasks of this master‘s work, the importance of atmosphere air management was taken into consideration in the context of sustainable development, Lithuanian and European Union laws and Lithuanian institutional structure of atmosphere protection management were analysed and suggestions related to the improvement of atmosphere protection management structure improvement were given. The... [to full text]

L'objectif de cette thèse est l'étude de la formation de nanoparticules carbonées dans un plasma basse pression. Les poussières sont créées par pulvérisation d'une couche de polymère déposée sur l'électrode d'une décharge radio fréquence à couplage capacitif. La présence des poudres perturbe et modifie les propriétés du plasma. La croissance des poudres peut notamment déclencher des instabilités basse fréquence qui évoluent avec la taille et la densité des poudres. Au centre du plasma, une région sans poudre, appelée void, est souvent observée. Cette région se caractérise en particulier par une forte luminosité. Différents diagnostics (mesures électriques, imagerie vidéo rapide, Fluorescence Induite par Laser) sont utilisées afin d'analyser ces différents comportements résultant des interactions entre le plasma et les poussières. L'analyse approfondie des instabilités a permis de mettre en évidence plusieurs régimes et d'extraire leurs principales caractéristiques comme leur durée et l'évolution de leurs fréquences. Ces instabilités se traduisent par la formation de petites "boules" de plasma qui se déplacent et interagissent au sein de celui-ci. Des phénomènes particulièrement surprenants de fusion et de division de ces boules ont été mis en évidence. Concernant le void, nos travaux ont confirmé la forte excitation présente dans cette zone. Dans la dernière partie de la thèse, la dissociation de l'aluminium triisopropoxide(ATI) est étudiée dans un plasma à l'aide de la Spectroscopie infrarouge à Transformée de Fourier. Ce diagnostic nous a permis de mettre en évidence l'évolution de la densité d'ATI en fonction des paramètres de la décharge. Nous avons également quantifié les différents composants hydrocarbonés formés par polymérisation. / The objective of this thesis is to study the formation of carbonaceous nanoparticles in a low pressure plasma. Dust particles are created by sputtering a polymer layer deposited on the bottom electrode of a capacitively coupled radio-frequency discharge. The presence of dust particles disturbs and changes the plasma properties. The growth of dust particles can trigger low frequency instabilities that evolve with the dust particle size and density. In the center of the discharge, the void, a dust-free region, is observed. It is characterized by an enhanced luminosity. Different diagnostics (electrical measurements, high speed imaging, Laser Induced Fluorescence) are used in order to understand these different behaviors resulting from plasma-dust particle interactions. Dust particle growth instabilities are investigated showing the existence of different instability regimes. Their main characteristics are extracted such as their duration and their evolution frequency. These instabilities are characterized by the formation of small plasma spheroids moving and interacting in the discharge. Several interesting phenomena are evidenced such as the merging and splitting of these plasma spheroids. Concerning the void, our investigations confirmed the high excitation occurring in this region. In the last part of the thesis, the dissociation of aluminium triisopropoxide (ATI) is studied in a plasma using Fourier Transform InfraRed spectroscopy. Thanks to this diagnostic, the evolution of ATI density has been studied as a function of the discharge parameters. We have also quantified the different hydrocarbon compounds formed by polymerization.

Kvartsdamm är ett arbetsmiljöproblem som kan leda till allvarliga konsekvenser för de exponerade yrkesarbetarna. De sjukdomar som ligger till följd för en hög exponering av kvartsdamm är framförallt silikos, KOL och lungcancer. Kvartsdammet uppstår då byggmaterial som innehåller kvartshaltigt material bearbetas, tillexempel betong. De små respirabla partiklarna av kvarts som uppstår vid bearbetningen bildar ärrvävnader i lungorna, vilket leder till att dem tappar sin kapacitet. Tidigare har krav ställts att arbetsplatserna ska utföra egna mätningar av kvarts, men inte längre. Nya författningssamlingen, AFS 2015:2 gör det möjligt för byggarbetsplatserna att använda sig av referensvärden och kringgå faktiska mätningar vid riskbedömningen av kvartsdamm. Examensarbetet redovisar några utav de hjälpmedel som används för en minskad exponering av dammet, där syftet är att hitta de största bristerna hos fallföretaget i byggproduktionen samt se hur den övergripande kunskapen ser ut på byggarbetsplatserna.Informationen till arbetet har samlats in från olika informationskällor, bland annat kvantitativa enkätundersökningar, semistrukturerade intervjuer samt informationssökning via internet där primärkällor prioriterats. Alternativa fakta har sorterats ut för en minskad avgränsning då examensarbetet enbart inriktar sig på den praktiska hanteringen av kvartsdamm.Examensarbetets resultat förväntas göra företagets riskbedömningsmall för kvartsdamm mer hanterbar genom den förenkling som tagits fram under arbetets gång. Diskussionerna har i huvudsak kretsat kring självkritisk bedömning av informationsinsamlingen samt hur utfallet av rapporten hade ändrats om fokus lades på andra delar vid arbetets början.Fallföretaget arbetar konstant med riskbedömning av kvarts för att uppnå en fullgod arbetsmiljö. En rotorsak var svårigheter kring just hanteringen av referensvärdena som gör att företaget inte använder riskbedömningsmallen som ett hjälpmedel. Då kvartsdamm ska bedömas i arbetsberedningarna är tanken att riskbedömningen som utförts i ett tidigare skede ska underlätta arbetet. Även kunskapen om kvartsdamm var varierande, där de anställda hos de större företagen har goda kunskaper medan de mindre underentreprenörerna har bristfälliga kunskaper. / Quartz dust is a health and safety problem that has serious consequences for the exposed workers. The diseases that are due to excessive exposure of silica are silicosis, COPD and lung cancer. The quartz dust occurs when building materials that containing quartz are processed, such as concrete. The small respirable quartz dust particles that occur during processing form scar tissues in the lungs, causing them to lose their capacity. In the past, demands have been made that workplaces should carry out their own measurements of quartz, but no longer. The new regulation, AFS 2015:2, enable construction sites to use benchmarks and circumvent actual measurements in the risk assessment of quartz dust. The study reports some of the tools used to reduce exposure to the dust, where the purpose is to find the biggest shortcomings of the case company in the construction production and see how the overall knowledge looks at the construction sites.The information for the work has been collected from various sources of information, including quantitative surveys, semi structured interviews and information retrieval via the Internet where primary sources have been prioritized. Alternative facts have been sorted out for a reduced demarcation as the degree project focuses solely on the practical handling of quartz dust. The discussion mainly revolved around self-critical assessment of information gathering. The discussion has also investigates how the outcome of the report have been changed if the focus had been other parts at the start of work.The case the company is constantly working with risk assessment of quartz to achieve an acceptable working environment. A isolating was a problem in dealing with the reference values, which means that the company does not use the risk assessment template as an aid. When quartz dust is to be assessed in the working preparations, the idea is that the risk assessment template facilitates the work. The knowledge of quartz dust was also variable, where the employees of the larger companies had good knowledge while the smaller subcontractors had inadequate knowledge.