Global ETD Search

11	Energikartläggning av integrerat massa- och pappersbruk / Energy survey of integrated pulp and paper mill Kristofersson, Josef, Samuelsson, Christian, Jonsson, Jonas January 2011 (has links) Målet med detta examensarbete har varit att utföra en energikartläggning på Nymölla Bruk med utgångspunkt i företagets beﬁntliga energiaspektregister. Syftet har varit att tydliggöra hur energianvändningen på Nymölla Bruk ser ut. Bakgrunden till detta arbete är företagets deltagande i programmet för energieffektivisering i energiintensiv industri (PFE). I examensarbetet har en energikartläggning på Nymölla Bruk för år 2010 utförts. Fallstudien delades in i två steg där första steget i studien var att kartlägga energiﬂödena in och ut från bruket.Andra delen av studien innefattade att kartlägga de interna processerna och deras energiﬂöden. Energiﬂödenas storlekar baseras främst på mätdata från processerna, som erhållits från Nymölla Bruks interna loggnings- och mätsystem WinMops. Antaganden som i vissa fall varit nödvändiga bygger på uppskattningar som genomförts i samråd med medarbetare på Nymölla Bruk med insikt i och kunskap om respektive delprocess. Enligt detta examensarbete förbrukades år 2010 cirka 510 GWh el, varav massafabriken förbrukade 50 % och pappersbruket 46 %. Resterande andel utgörs bland annat av mät- och överföringsförluster. Under året tillfördes totalt 2060 GWh bränsle där luten står för cirka 75 %. Från bränslena tillfördes 1800 GWh nyttig värme till ångproduktionen. Total energimängd i producerad ånga uppgick till cirka 2190 GWh (från referensnivå). De största förbrukarna av ånga var papperstillverkningen som använde 32 % och indunstningen som använde 19 % av total energimängd distribuerad med ånga. / The aim of this study was to perform an energy survey of Nymölla Mill on the basis of the company's existing energy aspect register. The aim has been to clarify how the energy at Nymölla Mill is used. The background to this thesis is the company's participation in the Programme for Improving Energy Efficiency in Energy Intensive Industries (PFE). In this thesis an energy survey based on 2010 of Nymölla Mill has been performed. The case study was divided into two stages where the first step in the study was to identify the energy flows in and out of the mill. The second part of the study included identifying the internal processes and their energy flows. Energy flows are based primarily on data from processes, obtained from Nymölla Mill's internal logging and measuring system WinMops. Necessary assumptions were made based on estimates provided in consultation with employees on Nymölla Mill with knowledge and understanding of each sub-process. According to this thesis approximately 510 GWh of electricity were consumed in 2010 of which the pulp factory consumed 50 % and the paper mill 46 %. The remaining portion consists of measurement and transmission losses. A total of 2060 GWh of fuel was added of which liquor accounts for about 75 %. From fuels 1800 GWh of useful heat was added to the steam production. The total amount of energy in the steam was about 2190 GWh (from baseline). The largest consumers of steam was the paper productioning unit using 32 % and the evaporation unit using 19 % of total energy distributed by steam. Energy survey Integrated pulp and paper mill sulphite process PFE sankey diagram Energikartläggning integrerat massa- och pappersbruk sulfitprocess PFE sankeydiagram
12	Analyse entropique et exergétique des systèmes énergétiques par des représentations géométriques / Geometric representations of exergy Canivet, Yvain 06 December 2017 (has links) À l’heure de la prise de conscience de la finitude des ressources et du besoin grandissant d'énergie, la notion de développement durable doit prendre une place centrale dans l'évolution de la société. Pour atteindre ce but, il est maintenant reconnu, qu'un changement de consommation profond est nécessaire ; et ce, qu'il s'agisse de consommation énergétique, alimentaire ou de produits finis. Nous croyons que ce changement de paradigme n’est possible que si tous les acteurs avancent de concerts sur les différentes problématiques auxquelles nous sommes confrontées. Chacun à son échelle doit ainsi pouvoir prendre les décisions qui s'imposent à tous. C'est la logique qui a motivé l'outil d'exergo-graphie présenté dans le chapitre 3. Inscrit dans la lignée des diagrammes de Sankey, il permet de représenter les bilans exergétiques sous forme graphique afin d’en communiquer plus facilement les enseignements. Nous l’appliquons à deux cas d'analyses faites sur les installations de chauffage et de production d’ECS du bâtiment A de l’UPN. Pour chacune, nous étudions la possibilité d’une solution de production durable de la chaleur (PAC géothermique et solaire thermique). Après en avoir présenté les analyses, nous en dressons les représentations graphiques que nous comparons à celles du système actuel. Au préalable, le chapitre 1 introduit les concepts de base de l’analyse exergétique, approfondis dans le chapitre 2, au travers d’une modélisation des systèmes fluides statiques et dynamiques. Finalement, dans le chapitre 4, nous introduisons un modèle-jouet qui, proposant une représentation fractale de la chaleur, tente d’établir un lien conceptuel entre le comportement microscopique, statistique, du support de la chaleur, et les observables macroscopiques qui la caractérisent. / At this time of awareness of the finiteness of resources, and of increasing needs for energy, the concept of sustainable development must play a central role in the forthcoming developments of our society. To do so, it is now an accepted fact that a deep change of our consumption habits is necessary; whether it is energy, food or final goods consumption. We believe this paradigm shift is only possible if all actors face together the various issues we are dealing with. Everyone, at one own scale, must be able to make informed decision. This is the idea that leads to the exergo-graphy tool presented in chapter 3. In line with the so called Sankey diagrams, it allows to graphically represent exergy balances in order to communicate more easily on their lessons. We apply it to two analysis done on the heating and DHW installations of the building A of the UPN. For each, we investigate the possibility of a sustainable heat production solution (geothermal heat pump and solar thermal energy). After presenting the analyses, we draw their graphical representations which we then compare to those of the current system. Beforehand, the first chapter introduces the basic notions of exergetic analysis, discussed further in chapter 2, through a model for static and dynamic fluid systems. Finally, in chapter 4, we introduce a toy-model which, proposing a fractal representation of exergy, tries to establish a conceptual link between microscopic, statistical, behaviour of heat background support, and the macroscopic observables that characterize it. Exergie Entropie Exergo-Graphie Anergie Diagramme de Sankey Représentation fractale Exergy Exergo-Graphy Anergy Entropy Sankey diagram Fractal analysis
13	Štíhlá výroba a její implementace / Lean Manufacturing and its Implementation Lévek, Martin January 2019 (has links) This thesis analyzes the materiál flow, layout of the workplace and varieties of waste in the chosen company. There is theoretical background for the thesis in the first part. Next part is focused on analyzing of present manufacturing process. There are provided solutions for lean implementation, better material flow and elimination of the waste in the manufacturing process in the last part.
14	Optimalizace toku materiálu v lisovně plastů / Optimization of Material Flow in the Moulding Shop Čermák, Jaroslav January 2008 (has links) Subject of the graduation theses is to propose improvement of the current terms and make a proposal for an amendment. Changes leading to the transportation retrenchment and to reduction of the material and moulding usage. Teoretical part contains characteristics of processes, methodology and philoshophy for improving of company processes.In the practical part is analysed problem, made propositions of process improvement and estimation of contributions solutions.
15	Optimalizace logistických procesů výroby testovacích stolic v podniku AVL Moravia / Optimization of logistic processes for the production of testing platforms in AVL Moravia company Váňa, Viktor January 2013 (has links) The main goal of a study is to rationalize organization of production and material handling in company AVL Moravia s.r.o. via material flow intensity analysis. Analysis results in suggesting new organization of production and economical rating of the suggestion.
16	Towards sustainable urban transportation : Test, demonstration and development of fuel cell and hybrid-electric buses Folkesson, Anders January 2008 (has links) Several aspects make today’s transport system non-sustainable: • Production, transport and combustion of fossil fuels lead to global and local environmental problems. • Oil dependency in the transport sector may lead to economical and political instability. • Air pollution, noise, congestion and land-use may jeopardise public health and quality of life, especially in urban areas. In a sustainable urban transport system most trips are made with public transport because high convenience and comfort makes travelling with public transport attractive. In terms of emissions, including noise, the vehicles are environmentally sustainable, locally as well as globally. Vehicles are energy-efficient and the primary energy stems from renewable sources. Costs are reasonable for all involved, from passengers, bus operators and transport authorities to vehicle manufacturers. The system is thus commercially viable on its own merits. This thesis presents the results from three projects involving different concept buses, all with different powertrains. The first two projects included technical evaluations, including tests, of two different fuel cell buses. The third project focussed on development of a series hybrid-bus with internal combustion engine intended for production around 2010. The research on the fuel cell buses included evaluations of the energy efficiency improvement potential using energy mapping and vehicle simulations. Attitudes to hydrogen fuel cell buses among passengers, bus drivers and bus operators were investigated. Safety aspects of hydrogen as a vehicle fuel were analysed and the use of hydrogen compared to electrical energy storage were also investigated. One main conclusion is that a city bus should be considered as one energy system, because auxiliaries contribute largely to the energy use. Focussing only on the powertrain is not sufficient. The importance of mitigating losses far down an energy conversion chain is emphasised. The Scania hybrid fuel cell bus showed the long-term potential of fuel cells, advanced auxiliaries and hybrid-electric powertrains, but technologies applied in that bus are not yet viable in terms of cost or robustness over the service life of a bus. Results from the EU-project CUTE show that hydrogen fuelled fuel cell buses are viable for real-life operation. Successful operation and public acceptance show that focus on robustness and cost in vehicle design were key success factors, despite the resulting poor fuel economy. Hybrid-electric powertrains are feasible in stop-and-go city operation. Fuel consumption can be reduced, comfort improved, noise lowered and the main power source downsized and operated less dynamically. The potential for design improvements due to flexible component packaging is implemented in the Scania hybrid concept bus. This bus and the framework for its hybrid management system are discussed in this thesis. The development of buses for a more sustainable urban transport should be made in small steps to secure technical and economical realism, which both are needed to guarantee commercialisation and volume of production. This is needed for alternative products to have a significant influence. Hybrid buses with internal combustion engines running on renewable fuel is tomorrow’s technology, which paves the way for plug-in hybrid, battery electric and fuel cell hybrid vehicles the day after tomorrow. / QC 20100722 acceptance analysis auxiliary system bus Clean Urban Transport for Europe concept CUTE demonstration driver drive cycle duty cycle energy flow evaluation fuel cell heavy duty vehicle hybrid management hybrid vehicle hydrogen passenger PEM safety Sankey diagram series hybrid sustainable test urban transport vehicle simulation acceptans analys hjälpaggregat buss Clean Urban Transport for Europe koncept CUTE demonstration körcykel förare energiflöde utvärdering bränslecell tunga fordon hybridsystemkontroll hybridfordon vätgas passagerare PEM säkerhet Sankey-diagram seriehybrid uthållig hållbar test stadstransport fordonssimulering Vehicle engineering Farkostteknik Chemical engineering Kemiteknik

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