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High resolution modelling of particulate matter air quality in the UK with a focus on carbonaceous aerosolOts, Riinu January 2016 (has links)
The Earth’s atmosphere consists of both gaseous and condensed-phase components, the condensed-phase material is called particulate matter (PM). The effects of atmospheric PM include adverse health impacts, as well as climate forcing. Both qualitative and quantitative knowledge about PM is necessary to assess these effects, and to devise best mitigation strategies. Understanding the distribution of atmospheric particulate matter is complex because much of it is of secondary origin rather than from primary emissions. Furthermore, there are multiple anthropogenic and natural sources of the contributing precursors, and all these processes are influenced by atmospheric conditions and transport. In this work, one of the major constituents of atmospheric PM - carbonaceous aerosol - is studied. A regional application of the EMEP MSC-W atmospheric chemical transport model - EMEP4UK - was used to model air pollution over the British Isles with a horizontal resolution of 5 km x 5 km. One-way nesting was used from the European computational domain of 50 km x 50 km to the finer spatial grid of EMEP4UK. Several model experiments were devised in order to investigate the well-known deficiency that models currently underestimate organic aerosol (OA) concentrations compared with observations. The model experiments were evaluated with comprehensive year-long novel measurements from the Clear Air for London (ClearfLo) campaign in 2012. Several sources of organic aerosol that are either missing, greatly underestimated, or may be spatially misplaced in official emissions inventories were re-evaluated. Firstly, missing diesel-related intermediate volatility organic compound (IVOC) emissions from diesel vehicles derived directly from field measurements at the urban background site during the 2012 ClearfLo campaign were added into the model. According to the model simulations, these diesel-IVOCs can explain on average ~30% of the annual secondary organic aerosol (SOA) in and around London. Furthermore, the 90- th percentile of modelled daily SOA concentrations for the whole year was 3.8 μgm-3, constituting a notable addition to total particulate matter. More measurements of these precursors (currently not included in official emissions inventories) is recommended. Secondly, spatially and temporally resolved emissions of cooking OA (COA; emissions from meat charbroiling, or frying and deep-frying) were developed. These emissions are currently neglected in European emissions inventories, yet measurements point to significant COA contribution to ambient PM concentrations (up to 2.0 μgm-3 on annual average for central London). The final COA emission source strength derived here (320 mg person-1 day-1) was spatially distributed to workday population density (as opposed to residential population density). The impact of COA on surface concentrations is spatially very limited, however, as the modelled concentrations dropped markedly outside of urban areas. For example, annual average modelled concentration for the Harwell location was just 0.1 μgm-3. Thirdly, redistributing 50% of non-industrial wood and coal burning emissions to residential population density (thus over-writing, in part, the assumption made by the national emissions inventory that only smokeless fuels are burned in smoke control areas) increased the modelled solid fuel OA (SFOA) concentration at the London North Kensington site to 0.8 μgm-3, from the Base run value (using the emissions’ spatial distribution and total as officially reported) of just 0.3 μgm-3. For comparison, the measured annual mean concentration of SFOA at this site was 1.0 μgm-3. Based on the model evaluation presented, redistribution of SFOA emissions into smoke control areas is justified, but further refinement of the amount, as well as the temporal emission profile of this component is necessary. The total effect of the three refinements undertaken in this work increased the model estimate of the annual mean OA concentration at the London North Kensington site from 1.8 μgm-3 to 3.8 μgm-3, which is much closer to the observed value of 4.2 μgm-3. Thus, this work has provided relevant insight into the nature and magnitude of missing, under-represented, and spatially inappropriately-distributed emissions of primary OA and OA precursors. Although the study area was focused on pollutant concentrations over the British Isles, all of the components examined here are of great relevance to the air quality in other countries as well — in Europe and globally. Therefore, the inclusion of these improvements into other air quality models and official emissions’ inventories is advised.
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Wood, money and habitat to burn: environmental issues and the role of the educatorTreweek, Allison, n/a January 2002 (has links)
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Evaluation on Health Impact of Government Support for GER (Traditional Dwelling) District's Electricity Night Rates in Ulaanbaatar CityNansalmaa, Erdenekhuu 07 May 2011 (has links)
During the last 10 years, air pollution has become one of the major public health problems in Ulaanbaatar city of Mongolia, and concentrations of pollutants were measured 3 to 50 times higher than WHO recommendation. This devastating air pollution is produced mostly by thousands of families who migrated from countryside and live in gers (traditional dwellings) in the suburban area which is not connected to the central heating system, and nearly all of them burn coal to keep them warm. Due to air pollution, residents living in Ulaanbaatar city suffer health problems that equal to the smoking of 4-5 packs of cigarettes. During the winter time, PM10 hourly average concentrations increased to 2,300 μg/m3, and daily average became over than 1,000 μg/m3 in the most polluted parts of the city. At present, Mongolian government has accepted that the health of Mongolian residents has deteriorated at an alarming level.
In January of 2011, Mongolian Parliament approved the Law on Reduction of Air Pollution in the Capital City to control air pollution and eliminate the gaps in practice. One main provision of this law was to improve ger district electricity transmission and distribution network and reduce the night-time price of electricity by 50 percent. Therefore, this study aimed to estimate direct health benefits of Government Provision on cutting electricity payment by 50 percent during the night time and analyze the efficiency of this program on reducing air pollution and its related health impact.
The study result showed when this new regulation is fully implemented in the ger districts, the annual consumption of coal and wood would be decreased by about 550,000 tons and 415,000 tons, accompanied by massive reduction of the emission. These changes would lead into noteworthy health benefits such as 15.7 and 17.4 percent of reduction of total and infant mortality rates and 4.3 and 4.7 percent decrease of cardiovascular and respiratory disease morbidity cases, annually.
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Caractérisation des variabilités temporelle et spatiale de la pollution en Île-de-France : De la mesure de l'exposition individuelle à la définition des sources / Characterization of the temporal and spatial variabilities of pollution in Île-de-France : From personal exposure measurements to sources definitionLanguille, Baptiste 02 December 2019 (has links)
La pollution atmosphérique résulte d’un mélange complexe de composés, des gaz et des particules, dont les effets sont notoirement néfastes. Les composés organiques volatils (COV) tiennent un rôle prépondérant dans la chimie atmosphérique et sont précurseurs d’ozone et d’aérosols organiques secondaires (AOS). En Île-de-France, l’exposition à la pollution est préoccupante ; or, des incertitudes significatives sont toujours associées aux sources de polluants, ainsi qu’à leur intensité et leurs variabilités à différentes échelles de temps et très peu d’investigations ont porté sur la quantification de l’exposition individuelle. Dans ce contexte, cette thèse a cherché à mieux caractériser les variabilités temporelle et spatiale de la pollution en Île-de-France.La fiabilité discutable des capteurs portables a été dépassée par l’élaboration d’un protocole de sélection et de qualification comprenant différents tests en mesures fixes, en chambre et en mobilité. Cette nouvelle méthodologie, basée notamment sur l’utilisation d’un outil combinant différents indicateurs statistiques, a été appliquée pour retenir l’AE51, le Cairclip et le Canarin, mesurant respectivement le carbone suie (BC), le dioxyde d’azote (NO2) et les particules (PM).Ces trois capteurs ont été déployés au cours de campagnes de mesures impliquant une trentaine de volontaires. L’exposition individuelle ainsi quantifiée est plus élevée à l’automne qu’au printemps et varie de manière substantielle en fonction des différents environnements fréquentés. La proximité de la circulation routière (pour le BC et le NO2) ainsi que les activités de cuisine et la fumée de tabac (pour les PM) présentent des contributions importantes à l’exposition totale (jusqu’à 34 %, 26 % et 44 % respectivement), alors même que le temps passé dans ces environnements est faible.En plus du trafic routier, le BC est traditionnellement imputé au feu de bois. Une campagne hivernale de mesures (3,5 mois) a permis d’imputer respectivement 22 % et 47 % des COV mesurés à ces deux sources. Certains composés ont été mesurés et associés au feu de bois pour la première fois en air ambiant comme le benzènediol et le méthylbutènone. Une comparaison avec l’inventaire régional des émissions a permis d’identifier des similitudes et des différences pour proposer des améliorations. / Air pollution results from a complex mixture of compounds, gases and particulate matter, whose effects have proven to be harmful. Volatile organic compounds (VOCs) play a major role in atmospheric chemistry and are precursors of ozone and secondary organic aerosols (SOAs). In Île-de-France, exposure to pollution is a concern; however, significant uncertainties are still associated with the pollutants’ sources, as well as their intensity and variability at different time scales, and very few investigations have focused on quantifying personal exposure. In this context, this research sought to better characterize the temporal and spatial variabilities of pollution in Île-de-France.The questionable reliability of portable sensors has been addressed by the design of a selection and qualification protocol including various tests in static measurements, controlled chamber and mobility. This new methodology, based in particular on the use of a tool combining different statistical indicators, was applied to choose the AE51, Cairclip and Canarin, measuring black carbon (BC), nitrogen dioxide (NO2) and particulate matter (PM) respectively.These three sensors were deployed during measurement campaigns involving about thirty volunteers. The personal exposure thus quantified is higher in fall than in spring and varies substantially according to the different environments frequented. Proximity to road traffic (for BC and NO2) as well as cooking activities and tobacco smoke (for PM) make significant contributions to total exposure (up to 34 %, 26 % and 44 % respectively), even though the time spent in these environments is short.In addition to road traffic, BC is traditionally attributed to wood burning. A winter measurement campaign (3.5 months) attributed respectively 22 % and 47 % of the measured VOCs to these two sources. Compounds including benzenediol and methylbuteone were measured and associated with wood burning for the first time in ambient air. A comparison with the regional emissions inventory identified similarities as well as differences and suggested improvements.
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Continuous real-time measurement of the chemical composition of atmospheric particles in Greece using aerosol mass spectrometryΦλώρου, Καλλιόπη 04 November 2014 (has links)
Atmospheric aerosol is an important component of our atmosphere influencing human health, regional and global atmospheric chemistry and climate. The organic component of submicron aerosol contributes around 50% of its mass and is a complex mixture of tens of thousands of compounds. Real-time aerosol mass spectrometry was the major measurement tool used in this work. The Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) can quantitatively measure the chemical composition and size distribution of non-refractory submicron aerosol (NR-PM1). The mass spectra provided by the instrument every few minutes contain information about aerosol sources and processes. This thesis uses the HR-ToF-AMS measurements in two areas of Greece to quantify the contributions of organic aerosol sources to the corresponding organic aerosol levels.
Local and regional air pollution sources were monitored and characterized in two sites during intensive campaigns. The first campaign took place during the fall of 2011 (September 24 to October 23) in Finokalia, Crete, a remote-background coastal site without any major human activity. The aim of the study was to quantify the extent of oxidation of the organic aerosol (OA) during autumn, a season neither too hot nor cold, with reduced solar radiation in comparison to summer. The second one took place during the winter of 2012 (February 26 to March 5), in the third major city of Greece, Patras. The measurements were conducted in the campus of the Technological Educational Institute of Patras (TEI), in order to quantify the severity of the wintertime air pollution problem in the area and its sources. The contributions of traffic and residential wood burning were the foci of that study.
The Finokalia site is isolated and far away from anthropogenic sources of pollution, making it ideal for the study of organic aerosol coming from different directions, usually exposed to high levels of atmospheric oxidants. The fine PM measured during the Finokalia Atmospheric Measurement Experiment (FAME-11) by the AMS and a Multi Angle Absorption Photometer (MAAP) was mostly ammonium sulfate and bisulfate (60%), organic compounds (34%), and BC (5%). The aerosol sampled originated mainly from Turkey during the first days of the study, but also from Athens and Northern Greece during the last days of the campaign. By performing Positive Matrix Factorization (PMF) analysis on the AMS organic spectra for the whole dataset the organic aerosol (OA) composition could be explained by two components: a low volatility factor (LV-OOA) and a semi-volatile one (SV-OOA). Hydrocarbon-like organic aerosol (HOA) was not present, consistent with the lack of strong local sources. The second field campaign took place in the suburbs of the city of Patras, 4 km away from the city center during the winter of 2012. During this 10-day campaign, organics were responsible for 70% during the day and 80% during the evening of the total PM1. The OA mean concentration during that period was approximately 20 μg m-3 and reaching hourly maximum values as high as 85 μg m-3. Sulfate ions and black carbon followed with 10% and 7% of the PM1. PMF analysis of the organic mass spectra of PM1 explained the OA observations with four sources: cooking (COA), traffic (HOA), biomass burning (BBOA), and oxygenated aerosol (OOA), related to secondary formation and long range transport. On average, BBOA represented 58% of the total OM, followed by OOA with 18%, COA and HOA, with the last two contributing of the same percentage (12%). / --
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Les délices de la flamme : la sensibilité au froid et à la chaleur dans la France moderne (XVIe - XVIIIe siècles) / Delights by the flame : sensitivity to the cold and heat in Modern France (16th-18th centuries)Jandot, Olivier 07 October 2016 (has links)
À une époque où les conditions matérielles de l’existence différaient profondément de celles qui sont aujourd’hui les nôtres, quel était l’impact des variations saisonnières de températures sur les individus et sur la société ? Comment les hommes et les femmes du passé enduraient-ils le froid de l’hiver et tentaient-ils de s’en préserver ? Quelle était l’efficience des moyens mis en œuvre pour lutter contre le froid et quelles pouvaient être les températures qui régnaient l’hiver à l’intérieur des habitations ? À la suite des intuitions pionnières de Lucien Febvre ou de Robert Mandrou, ce travail, à la croisée de l’histoire du corps et de celle des sensibilités, tente de de retracer la généalogie de notre rapport sensible au monde. La première partie de la thèse, après avoir évoqué les apports et les limites des différents types de sources dépouillées, est consacrée à étudier la manière dont les fluctuations de températures sont perçues, notées et pensées à des époques où le froid et la chaleur sont davantage des expériences sensibles que des grandeurs physiques mesurables. On y étudie aussi la manière dont les vagues de froid impactent, plus qu’aujourd’hui, la vie quotidienne et posent aux individus et à la société d’insolubles difficultés. En s’interrogeant sur la figure récurrente du “grand hiver”, on en vient à montrer que ces descriptions d’hivers rigoureux révèlent tout autant une réalité climatique objective qu’une extrême vulnérabilité des sociétés anciennes face au froid. La seconde partie centrée autour de la question de la civilisation matérielle tente de retracer les différentes stratégies mises en œuvre pour lutter contre les assauts de l’hiver. On y étudie ainsi la place et le rôle de la cheminée dans l’habitation ainsi que la manière dont elle constitue un trait de civilisation qui conditionne des manières d’habiter et des attitudes corporelles qui n’échappent pas au processus de civilisation. Les médiocres performances calorifiques de la cheminée expliquent le recours nécessaire à des sources de chaleur portatives et la mise en place de multiples stratégies de lutte contre le froid qui varient en fonction des régions et des milieux sociaux. La France préindustrielle apparaît ainsi comme un monde de l’économie permanente et de la chaleur rare où le souci constant de l’économie du combustible explique la cohabitation recherchée avec les bêtes, l’entassement des corps dénoncés par les médecins des Lumières et l’existence de certaines formes de sociabilité. En essayant de reconstituer la cohérence d’un système et d’habitus aujourd’hui disparus, on est naturellement amené, dans une troisième partie, à poser la question de la sensibilité — au sens physiologique mais aussi social du terme — au froid et à la chaleur ainsi que celle de son évolution. Dans un essai d’archéologie du corps, on tente de reconstituer les climats intérieurs des habitations d’autrefois en s’efforçant de déterminer les températures de confort. L’accoutumance à des températures intérieures relativement basses au regard de nos exigences actuelles amène à souligner le caractère socialement et culturellement construit des seuils de tolérance et à interroger le rapport à l’inconfort et à la douleur puisque le froid, s’il est enduré, n’en provoque pas moins souffrances et lésions corporelles. En étudiant les cheminements sinueux de la réflexion technique relative à la question du chauffage qui se développe au cours du XVIIIe siècle, on est aussi amené à s’interroger sur les interactions complexes entre la société, les évolutions scientifiques et technologiques et l’évolution des seuils de tolérance individuels et sociaux au froid et à la chaleur. Le XVIIIe siècle apparaît ainsi comme un siècle charnière où s’exprime pour la première fois ouvertement une demande sociale de chaleur (condamnée par les moralistes et les médecins) qui préfigure notre besoin insatiable de confort..... / At the time when material conditions in our existence deeply differed from those we know nowadays, what was the impact of the change in the seasonal temperatures on the individuals and society? How did the men and women of the past endured winter cold and how did they strive to protect themselves from it? How efficient were the means used to fight the cold and what could the indoor temperatures be in winter? After the first intuitions sensed by Lucien Febvre and Robert Mandrou, this work, at the crossroads of the history of the body and that of sensitivity, tries to trace out the genealogy of our sensitive relation to the world. After mentioning the contributions and the limits found in various types of studied sources, the first part of this dissertation is devoted to the way the change in temperatures were perceived, noted or thought at a time when cold and heat were more perceptible experiences than measurable physical quantities. It also deals with the way the cold spells affected daily life and that more than today troubled both the individuals and society with unsolvable difficulties. Wondering about the recurring figure of the “great winter”, it shows that those descriptions of harsh winters revealed a climatic reality as much as the old societies’ extreme vulnerability to the cold. The second part revolving around the question of the material civilization tries to recount the different strategies used to fight the onslaught of winter weather. Thus it studies the role and importance of fire places in homes as well as the way it brought a feature of civilization which changed both the living conditions and the physical attitudes that were implied in the process of civilization. The poor calorific value of fire places explained the necessary resort to mobile heating sources and the establishment of numerous strategies to fight the cold, which changed according to the regions and the social standing. Thus, Preindustrial France was understood as a world of permanent economy and of scarce heat where the constant question of the combustible material economy could explain the importance of living with cattle, of overcrowded places - denounced by the doctors in the Age of Enlightenment - and the existence of certain forms of social skills. Trying to recreate the coherence of a system and habitus that have disappeared today, a third part naturally raises the question of sensitivity – in the physiological but also social meaning of the term – to cold and heat and its evolutions. In an essay on the archeology of the body, we tried to recreate the conditions inside the dwellings of the past, in an effort to determine the comfort temperature. The compliance with relatively low indoor temperatures regarding our current demands led us to underline that our capacity to acceptance had been culturally and socially built up and to question our relation to discomfort and pain since the cold, even though it was supported, entailed suffering and physical damage. Pondering over the technical reflection to the heating issue that had developed throughout the 18th century, we were led to go over the complexity of the interaction between society, scientific and technologic evolution and the individual and social acceptance to the cold and heat. The 18th century seemed to be the turning point where for the first time a social demand for heat had been overtly expressed (though condemned by both moralists and doctors) which heralded our unquenchable need for comfort. The expression for that social demand did not necessarily mean that it would be universally satisfied. Consequently, the old thermal regime would be lasting beyond this studied period…
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Odbourávání vybraných xenobiotik na komunálních čistírnách odpadních vod. / Removal of selected xenobiotics at municipal WWTP´sŽižlavská, Adéla January 2019 (has links)
The development of the chemical and pharmaceutical industry and the massive use of synthetic substances in various industries has become indispensable for our society. Unfortunately, this progress has brought a whole new kind of pollution. It is a group of substances which imagine for living organisms’ greater risk than 'normal' organic pollution. Because they have extraneous origin compared with naturally occurring compounds, they are called "Xenobiotics." It is a group comprising a large number of different substances, with dissimilar physical, chemical and biological properties such as pharmaceuticals, pesticides, detergents, paints, varnishes, plastic packaging, food additives, cosmetic products, drugs, and many others. Although these substances began to enter the water cycle as early as 30 years of the 20th century, their concentration often moves to the limit of the detection limit, so their presence in the water began to be examined in more detail in the 1980s, following the development of analytical technologies chemical composition of water. The main danger of these substances is that doesn’t primarily effect on water quality, but directly affect on the organisms by confusing of the endocrine system or by directly damaging RNA or DNA, causing mutagenic changes, cancer-causing proliferation, birth defects, metabolic disorders, gender changes, the degeneration of reproductive capacity of entire populations or the disappearance of self-preservation instinct. The source of xenobiotics in the water cycle is predominantly wastewater, which generated through the wastewater treatment, which not designed to eliminate this type of pollution. he dissertation thesis deals with the issue of xenobiotics in wastewater and is divided into the theoretical and experimental part. The theoretical part summarizes the xenobiotics current state of knowledge in wastewater from their history, origin, classification, possibilities of elimination to impacts on the environ
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Qualité de l'air dans la Vallée de l'Arve : météorologie locale et mesures des réductions des émissions liées au chauffage au bois / Arve Valley Air Quality : meteorology and measures of reduction of biomass burning emissionAllard, Julie 27 September 2018 (has links)
La combustion de la biomasse, en particulier le chauffage au bois résidentiel, constitue une source d’émissions fortement contributrice aux concentrations de PM10 en hiver, de façon globale, en Europe. Afin de réduire les émissions de cette source, un programme de large envergure de renouvellement d’appareils de chauffage au bois non-performant, le Fonds Air Bois a été lancé depuis 2013 dans la vallée de l’Arve. Cette action étant amenée à se multiplier en France, l’évaluation de son effet sur les concentrations atmosphériques constitue un enjeu pour les futures politiques de gestion de la qualité de l’air. Le programme PRIMEQUAL DECOMBIO (2013-2018) a été proposé afin de mettre en place des méthodologies permettant d’évaluer l’impact de cette opération sur les concentrations de PM10 à partir de mesures de terrains. Ce programme DECOMBIO, qui a servi de cadre à ce travail de thèse, s’est appuyé sur la confrontation durant 4 hivers des mesures en continu des PM10 issus de la combustion de la biomasse (noté PM10wb), des conditions météorologiques, et des variations d’émissions liées au renouvellement des appareils. Pour répondre à cet enjeu, les travaux de cette thèse ont eu pour objectif de développer des méthodes permettant de prendre en compte l’influence des conditions atmosphériques sur les concentrations hivernales de PM10 et d’évaluer les paramètres et facteurs d’incertitudes permettant de comparer les variations estimées d’émissions de PM10wb avec celles des concentrations mesurées de PM10wb au cours des 4 hivers.Ces travaux se sont appuyés sur d’importantes bases de données de mesures chimiques et météorologiques constitués durant 4 hivers (13-14 à 16-17) au niveau de 3 sites dans la vallée de l’Arve. Par ailleurs, les données techniques issues des dossiers de renouvellements des appareils pour bénéficier de l’aide financière du Fonds Air Bois nous ont été communiquées, nous permettant de spatialiser et temporaliser les réductions des émissions de PM10wb estimées provenant de ces remplacements d’appareils. L’état de la stabilité thermique de l’atmosphère, paramètre essentiel pour déterminer les épisodes d’inversions thermiques, a été suivi en continu grâce à un système peu onéreux de capteurs de température sous abris installés le long des pentes. Ces mesures ont permis de montrer que les conditions météorologiques locales dans ces vallées encaissées sont le facteur premier conditionnant les concentrations atmosphériques. Une classification automatique des conditions atmosphériques a été établie, permettant de s’affranchir de cette variabilité et de comparer les concentrations pour des conditions atmosphériques similaires entre les différents hivers. L’innovation de cette approche repose principalement sur la prise en compte du degré d’influence de variables météorologiques et de paramètres liés à l’intensité des émissions. Une diminution graduelle des concentrations de PM10wb au cours des hivers a ainsi pu être constatée au niveau des 3 sites pour certaines classes de conditions atmosphériques, résultat consolidé par la diminution concomitante des traceurs de la combustion de la biomasse à la masse des PM10. Afin de préciser ces résultats, nous nous sommes intéressés à estimer la réduction des émissions de PM10 des remplacements d’appareils au niveau des sites de mesures et leurs incertitudes.Au terme de ce travail et du programme DECOMBIO, nous avons été à même de développer et de valider plusieurs outils méthodologiques applicables dans l’évaluation de futurs fonds air bois (utilisation de capteurs le long des pentes, classification météorologique adaptée à la qualité de l’air, estimation des incertitudes sur les émissions de parc de dispositifs de chauffage au bois). Ces bases solides nous ont permis de mieux comprendre les mesures réalisées sur les PM atmosphériques, et leurs liens avec les estimations des émissions. / Biomass burning, particularly residential wood burning, is a source of atmospheric particles that contributes significantly to winter PM10 levels globally in Europe. In order to reduce emissions from this source, a large-scale program for the renewal of non-efficient wood-burning appliances, the “Fonds Air Bois” has been launched since 2013 in the Arve Valley. The assessment of its impact on atmospheric concentrations is an issue for future air quality management policies. The research DECOMBIO program (2013-2018) has been proposed to evaluate the impact of this operation on PM10 concentrations from measurements. This DECOMBIO program, which includes these thesis works, was based on the confrontation during 4 winters of continuous measurements of PM10 resulting from biomass burning (noted PM10wb), weather conditions, and emissions variations related to appliances renewal. To answer this challenge, the aim of this thesis was to develop methods to take into account the influence of atmospheric conditions on winter PM10 concentrations and to evaluate the parameters and uncertainties that make it possible to compare the estimated PM10wb emission variations with those of the measured PM10wb concentrations during the 4 winters.This work was based on large datasets of chemical and meteorological measurements made during 4 winters (13-14 to 16-17) at 3 sites in the Arve Valley. In addition, the technical data from wood appliances renewal files was provided to us, allowing us to spatially and temporally estimated reductions of PM10wb emissions from these appliances replacements. The state of atmospheric stability, an essential parameter for determining episodes of temperature inversions, has been continuously monitored thanks to an inexpensive system of sheltered temperature sensors installed along the slopes. These measurements have shown that local weather conditions in these valleys are the primary factor conditioning atmospheric concentrations. An automatic weather types classification has been established, making it possible to overcome this variability and to compare the concentrations for similar atmospheric conditions between the different winters. The innovation of this approach is mainly based on taking into account the degree of influence of meteorological variables and parameters related to the intensity of emissions. A gradual decrease of PM10wb concentrations during winters was thus observed at the 3 sites for certain weather types, a result consolidated by the concomitant decrease in tracer biomass combustion at the mass of PM10. To clarify these results, we were interested in estimating the reduction of PM10 emissions from device replacements at measurement sites and their uncertainties.At the end of this work and of the DECOMBIO program, we have been able to develop and validate several methodological tools applicable in the evaluation of future “fonds air bois” (use of sensors along the slopes, meteorological classification adapted to the quality of the air, estimation of uncertainties on wood appliances renewable emissions). This solid foundation has allowed us to better understand the measurements made on atmospheric PM, and their relationship to emission estimates.
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Utvärdering av kommersiell TEG-enhet på en värmeplatta : Generering av elektricitet från temperaturskillnader / Evaluation of commercial TEG on a heatplateSvensson, Andreas January 2021 (has links)
Att minska energianvändningen är något det pratats mer och mer om de senaste åren. Det finns olika sätt att minska energianvändningen på och ett av dessa är att återvinna värmeenergi. Det kan gälla både spillvärme och nyttig värme. Detta går att tillämpa i industrin, transportsektorn, hushåll och till vardags. Gemensamt för dessa processer är att det används stora mängder energi vilket till stor grad består av förluster till omgivningen eller att processerna inte optimeras. På senare tid har det forskats kring teknologi som kan ta vara på denna värmeenergi och på så vis minska förlusterna. En teknologi för detta är termoelektriska generatorer (TEG) som bygger på Seebeckeffekten för att generera elektricitet från temperaturskillnader. När ett TEG-element utsätts för värme på en sida och kyla på den andra sidan så genereras en elektrisk spänning. En elektrisk ström och effekt kan tas ur kretsen om elementet kopplas till en elektrisk last. Materialet i elementet består av halvledarmaterial med låg värmeledningsförmåga och en hög elektrisk ledningsförmåga. Teknologin har funnits länge men aldrig tillämpats i någon större grad. Nu på senare år har intresset ökat och kommersiella produkter med TEG-element har tagits fram. I detta arbete har en sådan produkt testats för att se hur lämpligt det skulle vara att använda dessa vid hushåll som inte är anslutna till elnätet och har en vedkamin för uppvärmning. TEG-enheten testas på en värmeplatta där ställbara temperaturer är möjliga för att testa prestandan vid temperaturerna 150° C, 200° C och 230° C. En krets sätts ihop för att kunna mäta av värden på spänning och ström vid olika laster som sätts med resistorer. Mätningarna görs med en ökning på 0,1 A vid varje mätning. Resultatet från dessa tester visar att maximal effekt på 14 W uppnås hos produkten vid 230° C. När modifiering av produkten görs för att öka temperaturskillnaden uppnås 17,8 W vilket tyder på att effekten ökar när delta T ökar. Den spänning som uppnås vid öppen krets var som högst 31 V och vid maximal effekt var den 17,8 V. Strömmen var då 1 A. De resultat som testerna gav levde inte upp till de 25 W som produkten sägs kunna ge. Produkten saknar även viktiga komponenter så som spänningsreglerare.Det går av både teori och tester avgöra att det är ett lämpligt sätt att använda sig av TEG-enheter för att generera små mängder elektricitet vid hushåll utan koppling till elnätet. / In recent years the topic of reducing the energy usage has been on the agenda. There are several ways of reducing the energy usage and one of these is to recycle heat energy. It could be both waste heat and useful heat. This can be implied to the industry, transport sector, households and on daily activities. The common factor between these is that large quantities of energy is used and to a large extent consists of losses to the surrounding or from processes that are not optimized. In recent time there has been done research around technology that can recycle and use this heat energy and in return reduce the energy usage. One technology to do this is thermoelectric generators (TEG) that are implementing the Seebeck effect to generate electricity from temperature differences. When a TEG-element have one side that is exposed to a heat source and one side being cooled down an electric voltage is being generated. An electric current and power can then be used from the circuit if the element is connected to an electric load. The material in the element exists of semiconductive materials with low heat conductivity and high electric conductivity. The technology has existed for a long time but has never been implemented to a larger extent. It is only in recent years that the interest has grown and some commercial products with TEG-elements has been developed. In this thesis one of these products has been tested to see how viable it would be to use these within a household that is not connected to the electrical grid and where the house is heated with a wood-burning stove. The TEG-product is tested on a heat plate where it is possible to set a desired temperature. The temperatures of 150° C, 200° C and 230° C are chosen for testing the performance of the product. A circuit is put together to be able to read the values of the voltage and current at different loads that are set with resistors. The measurements are done with an increase of 0,1 A for every measurement. The result from these tests shows that the maximum power of 14 W is achieved at 230° C on the hot side. But when modification of the product is made to increase the temperature difference a value of 17,8 W is attained. This indicate that the power is increasing when the temperature difference is increasing. The attained voltage at open circuit was as highest 31 V and at maximum power it was 17,8 V. The current was then 1 A. The results that the testing gave did not match the value of 25 W that the datasheet says the product can deliver. Also, the product is missing important components such as voltage regulator.It is possible from both the theory and the testing to see that it is suitable to use a TEG-product to generate small amount of electricity to households that are not connected to the electrical grid.
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Semipermeable membrane devices as integrative tools for monitoring nonpolar aromatic compounds in airSöderström, Hanna January 2004 (has links)
<p>Air pollutants pose a high risk for humans, and the environment, and this pollution is one of the major environmental problems facing modern society. Active air sampling is the technique that has been traditionally used to monitor nonpolar aromatic air pollutants. However, active high volume samplers (HiVols) require a power supply, maintenance and specialist operators, and the equipment is often expensive. Thus, there is a need to develop new, less complicated sampling techniques that can increase the monitoring frequency, the geographical distribution of the measurements, and the number of sites used in air monitoring programs. In the work underlying this thesis, the use of semipermeable membrane devices (SPMDs) as tools for monitoring gas phase concentrations of nonpolar aromatic compound was evaluated using the compound classes polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkyl-PAHs) and nitrated PAHs (nitro-PAHs) as test compounds. </p><p>High wind-speeds increased the uptake and release in SPMDs of PAHs and PCBs with log K<sub>OA</sub> values > 7.9, demonstrating that the uptake of most nonpolar aromatic compounds is controlled by the boundary layer at the membrane-air interface. The use of a metal umbrella to shelter the SPMDs decreased the uptake of PAHs and PCBs by 38 and 55 percent, respectively, at high wind/turbulence, and thus reduced the wind effect. Further, the use of performance reference compounds (PRCs) to assess the site effect of wind on the uptake in SPMDs reduced the between-site differences to less than 50 percent from as much as three times differences in uptake of PCBs and PAHs. However, analytical interferences reduced the precision of some PRCs, showing the importance of using robust analytical quality control.</p><p>SPMDs were shown to be efficient samplers of gas phase nonpolar aromatic compounds, and were able to determine local, continental and indoor spatial distributions of PAHs, alkyl- PAHs and nitro-PAHs. In addition, the use of the SPMDs, which do not require electricity, made sampling possible at remote/rural areas where the infrastructure was limited. SPMDs were also used to determine the source of PAH pollution, and different approaches were discussed. Finally, SPMDs were used to estimate the importance of the gas phase exposure route to the uptake of PAHs in plants. The results demonstrate that SPMDs have several advantages compared with HiVols, including integrative capacity over long times, reduced costs, and no need of special operators, maintenance or power supply for sampling. However, calibration data of SPMDs in air are limited, and spatial differences are often only semi-quantitatively determined by comparing amounts and profiles in the SPMDs, which have limited their use in air monitoring programs. In future work, it is therefore important that SPMDs are properly sheltered, PRCs are used in the sampling protocols, and that calibrated sampling rate data, or the SPMD-air partition data, of specific compounds are further developed to make determination of time weighted average (TWA) concentrations possible.</p>
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