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The Effects of Circulating Aeration Systems On VOC Emissions from Aeration BasinsSUNDRUP, JASON PAUL January 2006 (has links)
No description available.
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Incident-response monitoring technologies for aircraft-cabin air qualityMagoha, Paul W. January 1900 (has links)
Doctor of Philosophy / Department of Mechanical Engineering / Steven J. Eckels / Byron W. Jones / Poor air quality in commercial aircraft cabins can be caused by volatile organophosphorus (OP) compounds emitted from the jet engine bleed air system during smoke/fume incidents. Tri-cresyl phosphate (TCP), a common anti-wear additive in turbine engine oils, is an important component in today’s global aircraft operations. However, exposure to TCP increases risks of certain adverse health effects. This research analyzed used aircraft cabin air filters for jet engine oil contaminants and designed a jet engine bleed air simulator (BAS) to replicate smoke/fume incidents caused by pyrolysis of jet engine oil. Field emission scanning electron microscopy (FESEM) with X-ray energy dispersive spectroscopy (EDS) and neutron activation analysis (NAA) were used for elemental analysis of filters, and gas chromatography interfaced with mass spectrometry (GC/MS) was used to analyze used filters to determine TCP isomers. The filter analysis study involved 110 used and 74 incident filters. Clean air filter samples exposed to different bleed air conditions simulating cabin air contamination incidents were also analyzed by FESEM/EDS, NAA, and GC/MS. Experiments were conducted on a BAS at various bleed air conditions typical of an operating jet engine so that the effects of temperature and pressure variations on jet engine oil aerosol formation could be determined. The GC/MS analysis of both used and incident filters characterized tri-m-cresyl phosphate (TmCP) and tri-p-cresyl phosphate (TpCP) by a base peak of an m/z = 368, with corresponding retention times of 21.9 and 23.4 minutes. The hydrocarbons in jet oil were characterized in the filters by a base peak pattern of an m/z = 85, 113. Using retention times and hydrocarbon thermal conductivity peak (TCP) pattern obtained from jet engine oil standards, five out of 110 used filters tested had oil markers. Meanwhile 22 out of 74 incident filters tested positive for oil fingerprints. Probit analysis of jet engine oil aerosols obtained from BAS tests by optical particle counter (OPC) revealed lognormal distributions with the mean (range) of geometric mass mean diameter (GMMD) = 0.41 (0.39, 0.45) [mu]m and geometric standard deviation (GSD), [sigma][subscript]g = 1.92 (1.87, 1.98). FESEM/EDS and NAA techniques found a wide range of elements on filters, and further investigations of used filters are recommended using these techniques. The protocols for air and filter sampling and GC/MS analysis used in this study will increase the options available for detecting jet engine oil on cabin air filters. Such criteria could support policy development for compliance with cabin air quality standards during incidents.
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Air Recirculation System for Electrolyte Filling Room : A CFD study of VOCs Distribution in Clean & Dry roomChen, Lin January 2022 (has links)
Energy storage development is an important step for the energy transition, meanwhile Lithium-ion battery is the most common core component of electric vehicles. Over the past decade, investment has been poured into lithium-ion battery production, as a result, the production environment (Clean & Dry room) used for some processes such as Stacking, Electrolyte filling and so on and the energy consumption to maintain this special environment which precise control of air humidity and air cleanliness have become major concerns. In this study, only one production process is concerned: electrolyte filling. During this process, Volatile Organic Compounds(VOCs) are the substance that affects air quality, also it is the reason that no air recovery in this Clean&Dry room before investigating the air quality, which leads to huge energy consumption for treating 100% fresh air. The main purpose of this thesis is studying the Volatile Organic Compounds(VOCs) distribution in the Clean&Dry room with electrolyte filling activity to check whether the air quality is good enough to be recycled. This part of the study was approached by combining ANSYS FLUENT and the onsite measurement. A secondary objective is studying the energy-saving of dehumidification system with air recirculation system, meanwhile do the environmental analysis and cost analysis. In the end, in order to safely recycle the air in the Clean&Dry room, the Building Automation System should be installed solve the worst case scenario. The conclusions drawn in this study include the Electrolyte Filling machine forms a ”negative pressure room” which means the Volatile Organic Compounds(VOCs) generated from the machine is not likely spreading to the room, and the energy-saving, carbon footprint decreasing, energy cost and the cost of Building Automation System were provided. / Utveckling av energilagring är ett viktigt steg för energiomställningen, samtidigt är litiumjonbatterier den vanligaste nyckelkomponenten i elfordon. Under det senaste decenniet har investeringar gjorts i produktion av litiumjonbatterier, som ett resultat av produktionsmiljön (Rent & torrt rum) som används för vissa processer som stapling, elektrolytfyllning och så vidare och energiförbrukningen för att upprätthålla denna speciell miljö där exakt kontroll av luftfuktighet och luftrenhet har blivit ett stort problem. I denna studie berörs endast en produktionsprocess: elektrolytfyllning. Under denna process är flyktiga organiska föreningar (VOC) ämnet som påverkar luftkvaliteten, vilket också är anledningen till att ingen luftåtervinning i detta rena&torra rum innan man undersöker luftkvaliteten, vilket leder till enorm energiförbrukning för behandling av 100% frisk luft. Huvudsyftet med denna avhandling är att studera distributionen av flyktiga organiska föreningar (VOC) i Clean&Dry-rummet med elektrolytfyllningsaktivitet för att kontrollera om luftkvaliteten är tillräckligt bra för att kunna återvinnas. Denna del av studien togs fram genom att kombinera ANSYS FLUENT och mätningen på plats. Ett sekundärt mål är att studera energibesparing av avfuktningssystem med luftcirkulationssystem, samtidigt gjorde miljöanalys och kostnadsanalys. I slutändan, för att säkert återvinna luften i Clean&Dry-rummet, bör Building Automation System implementeras för att lösa det värsta scenariot. Slutsatserna som dras i den här studien inkluderar att elektrolytfyllningsmaskinen bildar ett ”negativt tryckrum” vilket betyder att de flyktiga organiska föreningarna (VOC) som genereras från maskinen sannolikt inte sprider sig till rummet, och det energibesparande, koldioxidavtrycket minskar, energi kostnaden och kostnaden för Building Automation System tillhandahölls.
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Effizienzsteigerung des Kunststoffblasformprozesses durch Optimierung des DrucklufteinsatzesZipplies, Daniel 21 October 2020 (has links)
Die ökologischen und ökonomischen Anforderungen der heutigen Zeit verlangen energieeffiziente Verarbeitungsverfahren. Vor diesem Hintergrund befasst sich diese Arbeit mit dem Kunststoffblasformprozess, der neben dem für die Kunststoffverarbeitung typischen hohen Energiebedarf zusätzlich ein hohes Maß an energieintensiv zu erzeugender Druckluft erfordert. Ausgehend von einer ausführlichen Energiebilanz des Extrusionsblasformprozesses wurde der zur Formgebung (Blasluft) und zur inneren Blasteilkühlung (Spülluft) benötigte Drucklufteinsatz als eine energetische Schwachstelle identifiziert. Zur Reduzierung des erforderlichen Druckluftaufwands bei der Formgebung wird die Prozessrückführung der Blasluft detailliert betrachtet. Weiterhin wird ein Speichersystem vorgestellt, das eine sekundäre Nutzung der bei der inneren Blasteilkühlung kontinuierlich anfallenden druckbehafteten Prozessabluft ermöglicht. Abschließend wird ein Ansatz zum effektiven Drucklufteinsatz bei der inneren Kühlung flaschenförmiger Blasteile aufgezeigt, der durch gezieltes Ausnutzen von für den Wärmeübergang günstiger Strömungsverhältnisse eine Kühlzeitverkürzung sowie eine Reduzierung des Druckluftaufwands verspricht.:1 Einleitung
2 Prozessanalyse des Blasformverfahrens
3 Motivation, Zielstellung und Aufbau der Arbeit
4 Energetische Bilanzierung des Extrusionsblasformverfahrens
5 Reduzierung des Druckluftaufwands bei der Formgebung
6 Sekundärnutzung der zur inneren Blasteilkühlung verwendeten Druckluft
7 Effektive Druckluftnutzung bei der inneren Kühlung flaschenförmiger Blasteile
8 Zusammenfassung und Ausblick / Today's ecological and economic requirements demand energy-efficient processing methods. Against this background, this thesis deals with the plastic blow moulding process, which, in addition to the high energy demand typical for plastics processing, requires a high degree of energy-intensive compressed air. Based on a detailed energy balance of the extrusion blow moulding process, the use of compressed air required for forming (blow air) and for internal cooling of the blowing parts (purge air) was identified as an energetic weak point. In order to reduce the amount of compressed air required for forming, a feedback process used to recycle the blowing air is investigated in detail. Furthermore, a storage system will be presented which allows a secondary use of the pressurized process exhaust air, which is continuously generated during the internal cooling of the blowing part. Finally, an optimization approach for the effective use of compressed air for the internal cooling of bottle-shaped blow-moulded parts is presented, which promises a shortening of the cooling time and a reduction of the compressed air required through the targeted use of favourable flow conditions for heat transfer.:1 Einleitung
2 Prozessanalyse des Blasformverfahrens
3 Motivation, Zielstellung und Aufbau der Arbeit
4 Energetische Bilanzierung des Extrusionsblasformverfahrens
5 Reduzierung des Druckluftaufwands bei der Formgebung
6 Sekundärnutzung der zur inneren Blasteilkühlung verwendeten Druckluft
7 Effektive Druckluftnutzung bei der inneren Kühlung flaschenförmiger Blasteile
8 Zusammenfassung und Ausblick
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