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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Eine neue Methode zur Optimierung der Auslegungsparameter von Kraftwerksprozessen ohne und mit Auskopplung von Energie- und Stoffströmen

Werner, Claudia 08 August 2011 (has links) (PDF)
Der Gegenstand dieser Arbeit ist eine neue Optimierungsmethode zur Minimierung der Produktkosten von Kraftwerksprozessen ohne und mit nachgeschalteten Anwendungen. Diese Methode, die Planern und Projektanten als Werkzeug zur Auslegung von Kraftwerken dienen soll, wird erläutert und exemplarisch zur Optimierung eines ausgewählten Gas- und Dampfturbinenkraftwerkes verwendet. Im Rahmen der Untersuchungen werden dabei zwei Varianten betrachtet: Der Kraftwerksentwurf/-betrieb ohne und mit Auskopplung von Energie- und Stoffströmen. Beim Kraftwerksentwurf/-betrieb mit Auskopplung von Energie- und Stoffströmen wird das Gas- und Dampfturbinenkraftwerk mit einer nachgeschalteten hybriden Meerwasserentsalzungsanlage verknüpft. Zur Identifizierung der jeweils zu optimierenden Komponenten/Parameter werden bei der neuen Methode Elemente der thermo- bzw. exergoökonomischen Analyse und der Sensitivitäts- und Trendlinienanalysen verwendet. Die Optimierung selbst folgt dem Koordinatenverfahren nach Gauß und Seidel. Anhand der Optimierungsergebnisse und der Kriterien ’Auswahl/Beitrag der Komponenten/Parameter’ sowie ’Rechenumfang’ wird die neue Optimierungsmethode mit bekannten thermo- bzw. exergoökonomischen Optimierungsmethoden (Quadranten-/Matrix-Methode, thermo-/exergoökonomische Kennzahlen-Methode) verglichen und bewertet. Zur Ergebnisdiskussion werden Parameterstudien erstellt. Abschließend werden Empfehlungen zur Gestaltung des untersuchten Gas- und Dampfturbinenkraftwerkes gegeben und Ansätze für weiterführende Forschungsarbeiten in der Kraftwerkstechnik abgeleitet.
62

Modélisation et conduite optimale d'un cycle combiné hybride avec source solaire et stockage / Modeling and control of an hybrid combined cycle with solar power production and storage

Leo, Jessica 10 November 2015 (has links)
Cette thèse s'intéresse à la coordination des sous-systèmes d'un nouveau genre de centrale de production d'énergie : un cycle combiné hybride (HCC - Hybrid Combined Cycle). Cette centrale HCC n'existe pas encore mais combine un cycle combiné gaz (CCG), un moyen de production solaire thermodynamique (miroirs cylindro-paraboliques) et un moyen de stockage thermique (stockage indirect de chaleur sensible utilisant deux réservoirs de sels fondus). Comment coordonner ces trois sous-systèmes de manière optimale lors des variations de demande de puissance ou des prix du gaz ?Dans un premier temps, chacun des trois sous-systèmes est étudié de manière indépendante afin d'obtenir, d'une part, un modèle physique permettant de caractériser le comportement dynamique du sous-système considéré et, d'autre part, un contrôle local qui agit en fonction des objectifs de fonctionnement prédéfinis. Un modèle du système complet interconnecté de l'HCC est ensuite obtenu en couplant les modèles des trois sous-systèmes. Enfin, une coordination des différents sous-systèmes est mise en place pour adapter le fonctionnement de chacun, en fonction des objectifs globaux de la centrale HCC complète, en optimisant les consignes de chaque sous-système. Dans ce travail, une coordination de type linéaire quadratique et une coordination de type optimale prédictive sont étudiées. Les résultats obtenus sont bien prometteurs : ils montrent, tout d'abord, que lors d'un appel de puissance, la commande coordonnée permet au système HCC de répondre plus rapidement, en utilisant plus efficacement la partie solaire. De plus, lorsque la demande subit beaucoup de variations, la partie solaire et la partie stockage absorbent toutes ces variations et la Turbine à Combustion (TAC) du CCG est beaucoup moins sollicitée. Lorsqu'il n'y a plus d'irradiation solaire, la partie stockage prend la relève pour continuer à produire de la vapeur solaire, jusqu'à ce que les stocks se vident. Finalement, le stockage permet d'ajuster la production de la TAC en fonction des prix du gaz. / This work concerns the subsystems coordination of a new type of power plant: a Hybrid Combined Cycle (HCC). This HCC plant is not yet build but consists of a Combined Cycle Power Plant (CCPP), a concentrated solar plant (parabolic trough) and a thermal storage system (a molten-salts two-tank indirect sensible thermal storage). How to coordinate these three subsystems optimally during variations in power demand or in gas price?First, each subsystem is studied independently in order to get on one hand a physical model that reproduces the dynamical behavior of the considered subsystem, and on the other hand, a local control that achieves an operation according to pre-specified objectives. Then, a model of the HCC system is obtained by coupling the models of the three defined subsystems.Eventually, a coordination of the subsystems is set up in order to adapt the behavior of each subsystem according to the global objectives for the full HCC system, by optimizing subsystem setpoints. In this study, a linear quadratic coordination and a model predictive coordination are designed. The obtained results are promising: they first show that during a power demand, the coordination allows the global system to quickly respond, using extensively the solar production. Besides, when the power demand undergoes many fluctuations, the solar and storage parts absorb these variations and the gas turbine of the CCPP is much less stressed. In addition, when there is no more solar radiation, the storage part continues producing solar steam, until storage tanks are empty. At last, the storage part allows to adjust the gas turbine production according to the gas prices.
63

Avaliação legal, ambiental e econômico-financeira da implantação de sistema próprio de tratamento de resíduos de serviços de saúde no HC-FMRP-USP para geração de energia / Legal, environmental and economic-financial assessment to implement a private system to treat medical waste at HC-FMRP-USP in order to generate energy

Juliana Chiaretti Novi 12 January 2012 (has links)
Encontrar soluções para a problemática dos resíduos e, em virtude da crescente demanda por energia, diminuir a dependência dos combustíveis fósseis têm constituído grandes desafios para os pesquisadores. O setor hospitalar é um potencial gerador dos chamados Resíduos de Serviços de Saúde (RSS) que também apresenta um alto consumo de energia em decorrência do seu período de funcionamento e de equipamentos que necessitam de infraestrutura adequada. Apesar de representarem uma pequena parcela perante o montante dos Resíduos Sólidos Urbanos (RSU), no Brasil, nem todos os geradores se preocupam com seu tratamento e destinação final. O emprego de tecnologias desenvolvidas para o tratamento desses resíduos com a possibilidade de recuperação energética deve ser avaliado. O Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto (HC-FMRP-USP) gera cerca de 1,9 ton/dia de RSS. Nesse contexto, o objetivo geral desta pesquisa foi avaliar a viabilidade legal, ambiental e econômico-financeira da implantação de um sistema próprio de tratamento de RSS no HCFMRP- USP para geração de energia. A metodologia foi estruturada em pesquisa exploratória, coleta de dados por meio de entrevistas semi-estruturadas com responsáveis pelo setor dos RSS no hospital, com pesquisadores da área da saúde, de escolas de engenharia, órgãos técnicos e indústrias fabricantes dos equipamentos; levantamento bibliográfico e análise de conteúdo. Para a avaliação econômico-financeira, foi empregada a avaliação custoefetividade. Estudos comparativos sobre os tipos de tratamento disponíveis e utilizados nacionalmente foram considerados. Assim, o processo que melhor se adequou ao sistema proposto foi o da incineração com tecnologia de gaseificação e combustão combinadas (GCC). Os resultados demonstraram que o sistema proposto está sob a égide da lei contemplando, inclusive, a Política Nacional de Resíduos Sólidos (PNRS), desde que mediante anuência do Conselho Gestor do campus da USP e de sua Comissão de Meio Ambiente, além do devido processo de licenciamento ambiental junto à CETESB e pré-análise dos RSS. Contudo, sob o aspecto ambiental há questões públicas e políticas sobre a aceitação de sua implantação no complexo hospitalar. Embora haja o emprego de avançada tecnologia, o equipamento avaliado necessita de instalação, manutenção e monitoramento adequados por profissionais capacitados para operá-los, a fim de se evitar possíveis danos às pessoas e ao meio-ambiente, para isso, os envolvidos devem agir com responsabilidade. Por fim, sob o aspecto econômico-financeiro houve um empate técnico entre os custos do tratamento realizado atualmente e os da proposta do investimento. Assim, esse último aspecto avaliado incidiu sobre o benefício implícito da decisão de se implantar ou não o processo. Portanto, considera-se a viabilidade da implantação de um sistema próprio para tratamento de RSS no HCFMRP-USP para geração de energia sob os três aspectos: legal, ambiental e econômicofinanceiro. / Finding solutions to the waste problem and reducing dependence on fossil fuels due to the growing demand for energy have become big challenges for researchers to deal with. Hospitals are large producers of Medical waste (MW) and also big energy consumers due to their long running hours and the running of equipment that demands adequate infrastructure. Despite accounting for a small share of all the Municipal Solid Waste (MSW) not all producers, in Brazil, are concerned about waste treatment and its final destination. The use of technologies developed with the aim of treating such waste in order to generate energy has to be assessed. The Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto (HCFMRP-USP) generates around 1.9 tons of waste per day. In this context, the general aim of this research program was to assess the legal, environmental and economic-financial feasibility of the implementation of a private system of biomedical waste treatment at HCFMRP-USP in order to generate energy. The method was structured in exploratory research, data gathering by means of semi-structured interviews with MW department staff at the hospital, with Health researchers, with Engineering College researchers, technical organizations and equipment manufacturers, besides bibliographic referencing and content analysis. Cost-effectiveness analysis was used for the economic-financial analysis. Comparative studies of the types of treatment available and used nationwide were taken into consideration. Thus, the process which best suited the proposed system was that of incineration by means of Gasification Combined Cycle (GCC). Results showed that the proposed system is under the support of Law and it also takes into consideration the National Policy for Solid Waste (NPSW), provided that it has the approval of the Director Council of the Administration of the campus of USP and of its Environment Committee as well as appropriate environmental licenses granted by CETESB and pre-analysis of MW. However, under the environmental aspect, there are public and political issues regarding the acceptance of this implementation in the hospital premises. Although there is the use of advanced technology, the equipment which was assessed needs to be installed, maintained and monitored adequately by professionals trained to operate it so as to avoid possible damage to humans and the environment. Staff involved must be responsible. Finally, under the economic-financial aspect there was a draw between the costs of the treatment conducted at present and those of the proposed investment. Therefore, this last aspect assessed prevailed over the implicit benefit of the decision on whether to implement the process or not. However, the feasibility of the implementation of a private MW treatment system at HC-FMRP-USP in order to generate energy is to be considered under the legal, environmental and economicfinancial aspects.
64

Projektové řízení výstavby technologického celku / Project construction management technology unit

Šaroun, Josef January 2012 (has links)
The target of this master thesis is specify the requirements, which come up while summing the investment aim of a new 40MW energetic unit, and show the overall project management. Thesis is divided into two parts. First part deals with project management from the investors point of view. There is also detailed concept study, technological description of piston co-generation units and combined cycle, concept design of calculated variations and their economical analysis. Second part is taken from the point of view of the main supplier. There is defined the range of operations, documents and official permissions needed for successful finish of the civil part of the energetic unit project.
65

Zvýšení výkonu mikroturbíny pracující v nepřímém oběhu / Increased power microturbines operating in indirect circulation

Polák, Luboš January 2012 (has links)
Turbogenerator unit 100B TGU, produced in the First Brno Engineering Velká Bíteš a.s., works in Brayton indirect circulation. The aim of this work is the proposal to increase performance levels of technological unit in which the micro-turbine is applied. The work presents various ways to increase performance and efficiency of circulation. The possible options are compared with each of the technological and economic terms. Based on these criteria was selected variant feeding additional water into the circulation. For this design was the work of a mathematical model based on, which was established as the economic balance of the selected variants. The thesis also proposes a technological scheme, which is already incorporated the selected variant and an outline of the verification tests.
66

Eine neue Methode zur Optimierung der Auslegungsparameter von Kraftwerksprozessen ohne und mit Auskopplung von Energie- und Stoffströmen

Werner, Claudia 22 June 2011 (has links)
Der Gegenstand dieser Arbeit ist eine neue Optimierungsmethode zur Minimierung der Produktkosten von Kraftwerksprozessen ohne und mit nachgeschalteten Anwendungen. Diese Methode, die Planern und Projektanten als Werkzeug zur Auslegung von Kraftwerken dienen soll, wird erläutert und exemplarisch zur Optimierung eines ausgewählten Gas- und Dampfturbinenkraftwerkes verwendet. Im Rahmen der Untersuchungen werden dabei zwei Varianten betrachtet: Der Kraftwerksentwurf/-betrieb ohne und mit Auskopplung von Energie- und Stoffströmen. Beim Kraftwerksentwurf/-betrieb mit Auskopplung von Energie- und Stoffströmen wird das Gas- und Dampfturbinenkraftwerk mit einer nachgeschalteten hybriden Meerwasserentsalzungsanlage verknüpft. Zur Identifizierung der jeweils zu optimierenden Komponenten/Parameter werden bei der neuen Methode Elemente der thermo- bzw. exergoökonomischen Analyse und der Sensitivitäts- und Trendlinienanalysen verwendet. Die Optimierung selbst folgt dem Koordinatenverfahren nach Gauß und Seidel. Anhand der Optimierungsergebnisse und der Kriterien ’Auswahl/Beitrag der Komponenten/Parameter’ sowie ’Rechenumfang’ wird die neue Optimierungsmethode mit bekannten thermo- bzw. exergoökonomischen Optimierungsmethoden (Quadranten-/Matrix-Methode, thermo-/exergoökonomische Kennzahlen-Methode) verglichen und bewertet. Zur Ergebnisdiskussion werden Parameterstudien erstellt. Abschließend werden Empfehlungen zur Gestaltung des untersuchten Gas- und Dampfturbinenkraftwerkes gegeben und Ansätze für weiterführende Forschungsarbeiten in der Kraftwerkstechnik abgeleitet.
67

Towards Flexible Power Generation Short-term Optimization of a Combined Cycle Power Plant Integrated with an Inlet Air Conditioning Unit

Mantilla Gutierrez, Weimar January 2019 (has links)
Combined cycle gas turbine power plants (CCGT), as part of the electricity generation fleet, are required to improve their flexibility to help balance the power system under new scenarios with high shares of variable renewable sources. Among the different possibilities to enhance the power plant performance, an inlet air conditioning unit offers the benefit of power augmentation and “minimum environmental load” reduction by controlling the gas turbine intake temperature using cold thermal energy storage and a heat pump. In this thesis, an evaluation of the conditioning unit impact over a power-oriented CCGT under a day-ahead optimized operation strategy is presented. To establish the hourly dispatch of the power plant and the right operation mode of the inlet condition unit bringing the desired benefits, a mixed-integer linear optimization was formulated aiming to maximize the operational profit of the plant within a 24 hours horizon. To assess the impact of the proposed unit operating under this control strategy, annual simulations of a reference power plant were developed with and without the unit, allowing to a comparison of their performance by means of technical and economic indicators. Furthermore, a case study changing equipment sizes was performed in order to identify trends of the power plant performance related to such parameters; and lastly, a sensitivity analysis on market conditions to test the control strategy response was included. The results indicate that the inlet conditioning unit together with the dispatch optimization increase the power plant operational profit trough the gain of power variation over peak and off-peak periods. For the specific case study in northern Italy, it is shown that a power plant integrated with the conditioning unit is more profitable in terms of net present value based on the undertaken investment figures. Related to the technical performance, it also shows that the unit reduces by 1,34% the minimal environmental load when part-load operations are required and that it can increase the net power output by 0.17% annually. All in all, this study presents the benefits of a dispatch optimization strategy when couple to a novel solution to increase CCGT flexibility. / Elproducerande kombikraftverk (CCGT) förväntas förbättra sin flexibilitet för att kunna bidra till stabilisering av elnätet i framtida scenarier med ökande andel variabla, förnybara energikällor. Av de diverse metoder som finns att tillgå för att förbättra ett kraftverks prestanda, erbjuder en inluftsbehandlingsenhet både fördelar med kraftförbättring samt minskning av “minimun environmental load”; genom att med hjälp av kall termisk energilagring och en värmepump kontrollera gasens inluftstemperatur till gasturbinen. I den här uppsatsen undersöks hur en sådan inluftsbehandlingsenhet påverkar prestandan hos en kraftproduktionsfokuserad CCGT när en optimerad driftsstrategi introduceras. För att bestämma kraftverkets elproduktion vid varje timme och det korrekta driftläget för luftbehandlingsenheten (för att uppnå tidigare nämnda eftersökta fördelar) formulerades ett linjärt optimeringsproblem med syfte att maximera kraftverkets driftsförtjänst under ett 24-timmars tidsspann. För att bedöma den föreslagna inluftsbehandlingsenhetens inverkan under den optimerade driftsstrategin genomfördes simuleringar av ett referenskraftverk med och utan nämnda enhet, varpå en jämförelse med avseende på teknisk prestanda och ekonomi genomfördes. Vidare genomfördes en fallstudie där storlek på diverse utrustning varierades för att kunna identifiera trender i kraftverksprestanda baserat på dessa parametrar; slutligen genomfördes en känslighetsanalys rörande hur luftbehandlingsenheten och kontrollstrategin reagerar vid olika marknader.. Resultaten indikerar att en inluftsbehandlingsenhet tillsammans med en optimerad driftsstrategi ökar kraftverkets driftsvinning genom en ökad variation i kraftuttag över peak och off-peak timmar. För fallstudien i norra Italien fanns att ett kraftverk med integrerad luftbehandlingsenhet är mer lönsamt sett till nuvärdesanalys. Gällande teknisk prestanda visade resultaten att enheten minskar den minsta miljöbelastningen med 1,34 % när delbelastningsdrift fordras, och att det kan öka nettokraftuttag med 0,17% årligen. Sammanfattningsvis presenterar denna studie fördelarna med ett driftsoptimerat kraftverk kopplat till en ny lösning för att öka flexibilitet hos CCGT:er.
68

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
69

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
70

Advanced modeling and simulation of integrated gasification combined cycle power plants with CO2-capture / Fortgeschrittene Modellierung und Simulation von GuD-Kraftwerken mit integrierter Kohlevergasung und CO2-Abtrennung

Rieger, Mathias 14 August 2014 (has links) (PDF)
The objective of this thesis is to provide an extensive description of the correlations in some of the most crucial sub-processes for hard coal fired IGCC with carbon capture (CC-IGCC). For this purpose, process simulation models are developed for four industrial gasification processes, the CO-shift cycle, the acid gas removal unit, the sulfur recovery process, the gas turbine, the water-/steam cycle and the air separation unit (ASU). Process simulations clarify the influence of certain boundary conditions on plant operation, performance and economics. Based on that, a comparative benchmark of CC-IGCC concepts is conducted. Furthermore, the influence of integration between the gas turbine and the ASU is analyzed in detail. The generated findings are used to develop an advanced plant configuration with improved economics. Nevertheless, IGCC power plants with carbon capture are not found to be an economically efficient power generation technology at present day boundary conditions.

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