As is now generally accepted, climate change and environmental degradation has largely been triggered by carbon emissions and energy modeling for policy analysis has therefore attained renewed urgency. It is important for governments to satisfy emission targets and timetables set down by international agreements without disregarding macroeconomic concerns and restrictions. In this study, we present a large-scale nonlinear optimization model that allows the analysis of macroeconomic and multi-sectoral energy policies in respect of technological and environmental options and scenarios. The model consists of a detailed representation of energy activities and disaggregates the rest of the economy into five main sectors. Economy-wide solutions are obtained by computing a utility maximizing aggregate consumption bundle on the part of a representative household. Intersectoral and foreign transaction balances are maintained using a modified accounting matrix. The model also computes the impact on macroeconomic variables of greenhouse gas (GHG) emission strategies and abatement schemes. As such the model is capable of producing solutions that can be used to benchmark regulatory instruments and policies. Several scenarios are presented for the case of Turkey in which the impact of a nuclear power programme and power generation coupled with carbon-capture-and-storage schemes are investigated as well as setting quotas on total and sectoral GHG emissions.

Les clathrates organiques, particulièrement ceux formés entre l’hydroquinone (HQ) et les gaz, sont des entités supramoléculaires montrant un potentiel intéressant comme matériau alternatif pour les applications de stockage et de séparation de gaz. Cette étude traite de l’évaluation du clathrate d’HQ pour la séparation du CO2 contenu dans les mélanges CO2/CH4 par réaction gaz-solide. D’un point de vue fondamental, différentes propriétés des clathrates d’HQ-CO2, -CO2/CH4 et -CH4 ont été analysées: signatures spectroscopiques, structures cristallines, morphologies, capacités de stockage de gaz, températures de relargage de gaz et températures de transition structurales. Ce travail offre aussi de nouveaux éléments de compréhension des mécanismes de formation et de dissociation des clathrates d’HQ. Il est montré que, pour capturer efficacement et sélectivement le CO2, la réaction d’enclathration doit être faite en utilisant l’intermédiaire « clathrate vide » formé à partir du clathrate d’HQ-CO2. D’un point de vue pratique, les courbes d’équilibre, les enthalpies de dissociation, et les occupations dans les conditions d’équilibre ont été déterminées pour les clathrates d’HQ-CO2 et -CH4 dans une gamme étendue de température allant de 288 à 354 K. De plus, la cinétique de la réaction d’enclathration a été étudiée expérimentalement et modélisée. Dans cette optique, un matériau composite à base d’hydroquinone a été développé, et permet de capter et stocker le gaz de manière réversible, et d’améliorer significativement la cinétique d’enclathration. Le procédé de séparation de gaz basé sur la formation du clathrate d’hydroquinone a aussi été étudié. L’influence des paramètres opératoires (i.e. temps de réaction, pression, température et composition du gaz d’alimentation) sur la cinétique de capture, la sélectivité et la capacité de stockage de gaz ont été évaluées à travers des expériences menées à l’échelle pilote. / Organic clathrate compounds, particularly those formed between hydroquinone (HQ) and gases, are supramolecular entities recently highlighted as promising alternatives for applications such as gas storage and separation processes. This study deals with an evaluation of the HQ clathrates to separate CO2 from CO2/CH4 gas mixtures through direct gas-solid reaction. On the fundamental point of view, new insights into several properties of the CO2-, CO2/CH4-, and CH4-HQ clathrates were studied: spectroscopic signatures, crystal structures, morphologies, gas storage capacities, guest release temperatures and structural transition temperatures. This work also offers new elements of understanding HQ clathrate formation and dissociation mechanisms. It is shown that, for capturing CO2 the most selectively and efficiently, the enclathration reaction has to be done with the “guest-free intermediate” derived from the CO2−HQ clathrates. On a practical point of view, the equilibrium curves, the dissociation enthalpies, and the occupancies at the equilibrium clathrate forming conditions, were determined for the CO2- and CH4-HQ clathrates in an extended range of temperature from about 288 to 354 K. Moreover, the kinetics of the gas-solid enclathration reaction were studied experimentally and modelled. In this way, HQ-based composite materials were developed and allows to reversibly capture and store gases, and to significantly improve the enclathration kinetics. The hydroquinone clathrate based gas separation (HCBGS) process was also investigated. The influence of the process operating parameters (i.e. reaction time, pressure, temperature and feed gas composition) on the CO2 capture kinetics, the selectivity toward CO2, and the storage capacity were assessed through experiments performed at pilot scale.

O Painel Intergovernamental de Mudanças Climáticas da ONU (IPCC) tem comprovado com nível de confiança cada vez maior, ao longo dos últimos anos, a forte relação entre o aumento da temperatura média global e o aumento dos gases de efeito estufa (GEEs) principalmente quanto ao gás que mais contribui para a composição desses gases: o gás carbônico ou CO2. O Brasil se insere no rol dos emissores desse gás, principalmente devido ao desmatamento das reservas florestais que possui. Assim, assumiu o compromisso na Convenção Quadro das Nações Unidas sobre Mudanças Climáticas (United Nations Framework Convention on Climate Change UNFCCC) de estabilizar suas emissões e inventariar periodicamente os seus GEEs. Dentro deste contexto, cabe também à indústria levantar sua parcela de responsabilidade significativa neste processo ameaçador para a vida no planeta terra. Desta forma, o principal objetivo do presente trabalho foi o de levantar e contabilizar o Inventário dos GEEs emitidos em 2006 por uma empresa que produz importantes insumos para a indústria de petróleo. A pesquisa bibliográfica sobre a metodologia mais adequada e sua aplicação para a empresa em estudo foram os principais objetivos específicos. A autora não encontrou fatores de emissão de CO2 (kg CO2/TJ do combustível, detalhado no decorrer deste trabalho) desenvolvidos no Brasil para levantar o inventário, com um nível razoável de confiança, que reflita a situação real e local. Toda a pesquisa bibliográfica feita mostrou que os trabalhos realizados mesmo por órgãos governamentais brasileiros usaram a metodologia do IPCC (versão anterior à usada neste trabalho) que foi elaborada por países desenvolvidos, que não é o nosso caso ou realidade. Foram feitas diversas visitas à empresa, levantadas todas as fontes potenciais de emissão, consumos e características de todos os combustíveis usados, bem como o levantamento do trabalho desenvolvido sobre geração de mudas de plantas no seu horto. Através de cálculos por essa metodologia reconhecida mundialmente (IPCC) a autora encontrou um valor em torno de 76.000 toneladas de CO2 emitidos pela empresa em 2006. A empresa neutralizou cerca de 80 toneladas de CO2, através da produção de mudas (para doação e plantio em torno de uma área que é um passivo ambiental) em seu horto e o que plantou na área desse passivo em 2006. Isso significou cerca de 0,1% do que emitiu / The Intergovernamental Panel Climate Change - IPCC from ONU has proved with higher level of confidence, along last years, a strong relation between the global average temperature increasing and the Greenhouse Gases increasing mainly about the biggest contributor to the composition in these gases: the carbonic gas or CO2. Brazil is included in the list of these gas polluters, mainly because of its deforestation. Then, it assumed the commitment with United Nations Framework Convention on Climate Change UNFCCC of stabilize and calculate his Greenhouse Gases (GHG) Inventory. In this context, the industries must to survey their part of responsibility in this threatening process for the life in this planet. For the reasons above, the main purpose from the present work is to calculate the Greenhouse Gases emissions inventory in 2006 from a enterprise that produces important inputs for a petroleum industry. The specific purposes were to research the bibliography about the most suitable methodology and its application for this enterprise. The author of this work didnt find any emission factors for CO2 developed in Brazil for calculate the inventory, with a reasonable level of confidence, which can show the real and local situation about this subject. Then, the entire bibliographic search done showed that the works found even in governmental institutions used the IPCC methodology, done by developed countries, that isnt our reality. For this study, it was done several visits to that enterprise and identified all the sources from these GHG, fuel uses and their quantities and intensive bibliographic searches about several national and international methodologies. It was seen the developed work done by this enterprise about generation of seedling (plants) in its market garden. It was chosen the IPCC methodology that was the tool to calculate about 76.000 t of CO2 emitted by the enterprise in 2006. This studied enterprise neutralized 80 t of CO2, through the production of plants cuttings (for donation to people and to plant in around an area that is an environmental passive) in its market garden and what it planted in that passive area in 2006. This was about 0,1% on that it emitted

O Painel Intergovernamental de Mudanças Climáticas da ONU (IPCC) tem comprovado com nível de confiança cada vez maior, ao longo dos últimos anos, a forte relação entre o aumento da temperatura média global e o aumento dos gases de efeito estufa (GEEs) principalmente quanto ao gás que mais contribui para a composição desses gases: o gás carbônico ou CO2. O Brasil se insere no rol dos emissores desse gás, principalmente devido ao desmatamento das reservas florestais que possui. Assim, assumiu o compromisso na Convenção Quadro das Nações Unidas sobre Mudanças Climáticas (United Nations Framework Convention on Climate Change UNFCCC) de estabilizar suas emissões e inventariar periodicamente os seus GEEs. Dentro deste contexto, cabe também à indústria levantar sua parcela de responsabilidade significativa neste processo ameaçador para a vida no planeta terra. Desta forma, o principal objetivo do presente trabalho foi o de levantar e contabilizar o Inventário dos GEEs emitidos em 2006 por uma empresa que produz importantes insumos para a indústria de petróleo. A pesquisa bibliográfica sobre a metodologia mais adequada e sua aplicação para a empresa em estudo foram os principais objetivos específicos. A autora não encontrou fatores de emissão de CO2 (kg CO2/TJ do combustível, detalhado no decorrer deste trabalho) desenvolvidos no Brasil para levantar o inventário, com um nível razoável de confiança, que reflita a situação real e local. Toda a pesquisa bibliográfica feita mostrou que os trabalhos realizados mesmo por órgãos governamentais brasileiros usaram a metodologia do IPCC (versão anterior à usada neste trabalho) que foi elaborada por países desenvolvidos, que não é o nosso caso ou realidade. Foram feitas diversas visitas à empresa, levantadas todas as fontes potenciais de emissão, consumos e características de todos os combustíveis usados, bem como o levantamento do trabalho desenvolvido sobre geração de mudas de plantas no seu horto. Através de cálculos por essa metodologia reconhecida mundialmente (IPCC) a autora encontrou um valor em torno de 76.000 toneladas de CO2 emitidos pela empresa em 2006. A empresa neutralizou cerca de 80 toneladas de CO2, através da produção de mudas (para doação e plantio em torno de uma área que é um passivo ambiental) em seu horto e o que plantou na área desse passivo em 2006. Isso significou cerca de 0,1% do que emitiu / The Intergovernamental Panel Climate Change - IPCC from ONU has proved with higher level of confidence, along last years, a strong relation between the global average temperature increasing and the Greenhouse Gases increasing mainly about the biggest contributor to the composition in these gases: the carbonic gas or CO2. Brazil is included in the list of these gas polluters, mainly because of its deforestation. Then, it assumed the commitment with United Nations Framework Convention on Climate Change UNFCCC of stabilize and calculate his Greenhouse Gases (GHG) Inventory. In this context, the industries must to survey their part of responsibility in this threatening process for the life in this planet. For the reasons above, the main purpose from the present work is to calculate the Greenhouse Gases emissions inventory in 2006 from a enterprise that produces important inputs for a petroleum industry. The specific purposes were to research the bibliography about the most suitable methodology and its application for this enterprise. The author of this work didnt find any emission factors for CO2 developed in Brazil for calculate the inventory, with a reasonable level of confidence, which can show the real and local situation about this subject. Then, the entire bibliographic search done showed that the works found even in governmental institutions used the IPCC methodology, done by developed countries, that isnt our reality. For this study, it was done several visits to that enterprise and identified all the sources from these GHG, fuel uses and their quantities and intensive bibliographic searches about several national and international methodologies. It was seen the developed work done by this enterprise about generation of seedling (plants) in its market garden. It was chosen the IPCC methodology that was the tool to calculate about 76.000 t of CO2 emitted by the enterprise in 2006. This studied enterprise neutralized 80 t of CO2, through the production of plants cuttings (for donation to people and to plant in around an area that is an environmental passive) in its market garden and what it planted in that passive area in 2006. This was about 0,1% on that it emitted

Offshore oil platforms are used for the exploitation and production of hydrocarbons and consist of a processing plant and a utility plant. The oil and gas industry operations are energy-intensive and, in the case of offshore platforms, the need to decrease energy consumption and reduce CO2 emissions has increased. In the oil and gas industry, the ISO 50001 standard promotes the implementation of energy management systems and proposes indicators based on energy. Interestingly, after several decades of knowledge of the concept of exergy, this has not been formally implemented in the programs and strategies of the oil and gas industry organizations. In this research, the implementation of the exergy method and the carbon capture and storage strategy for the assessment of the performance of a floating, production and storage offloading units FPSO is proposed. FPSO platforms and their processing and utility plants may have different configurations depending on, among others, the reservoir characteristics and production requirements. The possible configurations can therefore be numerous. In this sense, some operation scenarios based on different well-fluid compositions and operation modes are studied. The platform models are developed and simulated using the software Aspen HYSYS®. Results show that, on average, the reduction of 88.8% in CO2 emissions is penalized with a reduction in exergy efficiency of 1.7 points. Further, results allow a better understanding of exergy and environmental performance of the FPSO. / Plataformas de petróleo offshore são utilizadas para a exploração e produção de hidrocarbonetos e consistem em uma planta de processamento e uma planta de utilidade. As operações da indústria de petróleo e gás são de energia intensiva e, no caso de plataformas offshore, é necessário cada vez mais diminuir o consumo de energia e reduzir as emissões de CO2. Na indústria de petróleo e gás, a norma ISO 50001 promove a implementação de sistemas de gestão de energia e propõe indicadores baseados em energia. Entretanto, após várias décadas de conhecimento do conceito de exergia, este não foi formalmente implementado nos programas e estratégias das organizações da indústria de petróleo e gás. Neste trabalho, propõe-se a implementação da análise exergética e a estratégia de captura e armazenamento de carbono para a avaliação do desempenho de unidades flutuantes, de produção, de armazenamento e transferência FPSO. As plataformas FPSO e suas plantas de processamento e utilidade podem ter diferentes configurações dependendo, entre outras, das características do reservatório e dos requisitos de produção. As configurações possíveis podem, portanto, ser numerosas. Neste sentido, são estudados alguns cenários de operação baseados em diferentes composições dos fluidos do poço e em três modos de operação. Os modelos de plataforma são desenvolvidos e simulados usando o software Aspen HYSYS®. Os resultados mostram que, em média, a redução de 88,8% nas emissões de CO2 é penalizada com uma redução da eficiência exergética de 1,7 pontos. Além disso, os resultados permitem uma melhor compreensão da exergia e desempenho ambiental do FPSO.

L’activité scientifique du sujet porte sur l’acquisition de données expérimentales et la modélisation de la composition des clathrates hydrates de gaz. Les domaines d’application concernent la séparation et le stockage de gaz, la purification de l’eau, et le stockage d’énergie par matériaux à changement de phase.L’équipe a mis en évidence il y a quelques années que la composition des hydrates de gaz était sensible aux conditions de cristallisation, et que le phénomène de formation se produisait en dehors de l’équilibre thermodynamique.Le travail de thèse a permis d’explorer plusieurs modes de cristallisation à partir de solutions de même composition initiale pour observer les différences concernant l’état final, compositions notamment, et les relier à la vitesse de cristallisation. Suivant le mode de cristallisation, lent ou rapide, l’acquisition des données expérimentales peut prendre de quelques jours à plusieurs semaines. Les expériences sont réalisées en réacteur pressurisé dans lequel nous mesurons en ligne la composition de la phase gaz et de la phase liquide, pour calculer par bilan de matière la composition de la phase hydrate.Nous avons bien mis en évidence des variations dans la composition de la phase hydrate suivant le mode de cristallisation. Nous avons dû établir un modèle thermodynamique donnant la composition de la phase hydrate à l’équilibre pour des mélanges de gaz qui n’avaient jamais été traité par la littérature, et qui ont donc nécessité des campagnes de mesure extrêmement lentes et donc longues pour être sûr de l’état thermodynamique à l’équilibre.Nous sommes en cours d’établir un modèle cinétique pour modéliser les écarts à cet état d’équilibre de référence pour nos expériences réalisées à vitesse de cristallisation rapide. / The scientific goal of this thesis is based on the acquisition of experimental data and the modeling of the composition of clathrates gas hydrate. The domains of application concern the gas separation and storage, water purification, and energy storage using change phase materials (PCMs).Our research team has recently demonstrated that the composition of gas hydrates was sensitive to the crystallization conditions, and that the phenomenon of formation was out of thermodynamic equilibrium. During this thesis, we have investigated several types of crystallization, which are based on the same initial states. The goal is to point out the differences between the initial solution composition and the final solution composition, and to establish a link between the final state and the crystallization rate.Depending on the rate of crystallization (slow or fast), the acquisition time of experimental data lasted from a few days to several weeks. The experimental tests were performed inside a stirred batch reactor (autoclave, 2.44 or 2.36 L) cooled with a double jacket. Real-time measurements of the composition of the gas and the liquid phases have been performed, in order to calculate the composition of the hydrate phase using mass balance calculations. Depending on the crystallization mode, we have identified several variations of the composition of the hydrate phase and final hydrate volume.We have established a successful thermodynamic model, which indicates the composition of the hydrate phase and hydrate volume in thermodynamic equilibrium state using a gas mixture which had never been used before in the literature. So this thermodynamic model has required an extremely slow experimental test. These tests were also long in order to be sure of the thermodynamic equilibrium state.We are currently establishing a kinetics model in order to model the deviations from the reference point of equilibrium of our experimental tests which were carried out at a high crystallization rate.

CO2 capture and storage (CCS) is estimated to reduce 14% of the global CO2 emissions in the 2 °C scenario presented by the International Energy Agency. Moreover, post combustion capture is identified as a potential method for CO2 capture from industry since it can be easily retrofitted without disturbing the core industrial process. Among the post-combustion capture methods, absorption using mono-ethanol amine (MEA) is the most mature technology that has been demonstrated at plant scale. However, using chilled ammonia process as a post combustion capture technology in a cement industry can reduce 47% energy penalty for CO2 capture when compared to the conventional MEA absorption method.  Hence, the current project aims at analyzing the chilled ammonia process when integrated with steel and ammonia plants. Key performance indicator like specific primary energy consumption per kilogram of CO2 avoided (SPECCA) is estimated and compared with MEA absorption method. Firstly, chilled ammonia process (CAP) for cement plant was used as reference case. Then, CAP for steel and ammonia processes was optimized by the means of the decision variables affecting the capture and energy efficiency. The energy consumption per kg CO2 captured and SPECCA was lower for the higher CO2 concentration in the flue gas. Results for SPECCA were 3,56, 3,52 and 3,61 MJ/kg CO2 for cement, steel, and ammonia plants, respectively.

The topic of this thesis is carbon dioxide (CO2) capture and storage (CCS), which is a technology that is currently being promoted by industries, scientists and governments, among others, in order to mitigate climate change despite a continued use of fossil fuels. Because of the complex nature of CCS and the risks it entails, it is controversial. The aim of this thesis is to analyse how the technology may be further developed in a responsible manner. In the first part of the thesis different methods for capturing CO2 from industrial processes as well as power plants are analysed. The aim is to identify early opportunities for CO2 capture, which is considered important because of the urgency of the climate change problem. Three potential early opportunities are studied: i) capturing CO2 from calcining processes such as cement industries by using the oxyfuel process, ii) capturing CO2 from pressurised flue gas, and iii) capturing CO2 from hybrid combined cycles. Each opportunity has properties that may make them competitive in comparison to the more common alternatives if CCS is realised. However, there are also drawbacks. For example, while capturing CO2 from pressurised flue gas enables the use of more compact capture plant designs as well as less expensive and less toxic absorbents, the concept is neither suitable for retrofitting nor has it been promoted by the large and influential corporations. The second part of the thesis has a broader scope than the first and is multidisciplinary in its nature with inspiration from the research field of Science and Technology Studies (STS). The approach is to critically analyse stakeholder percep-tions regarding CCS, with a specific focus on the CCS experts. The thesis sheds new light on the complexity and scientific uncertainty of CCS as well as on the optimism among many of its proponents. Because of the uncertain development when it comes to climate change, fossil fuel use and greenhouse gas emissions, the conclusion is that CCS has to be further developed and demonstrated. A responsible strategy for a future development of CCS would benefit from: i) a search for win-win strategies, ii) increasing use of appropriate analytical tools such as life-cycle analysis, iii) a consideration of fossil fuel scarcity and increasing price volatility, iv) funding of unbiased research and v) increasing simultaneous investments in long-term solutions such as renewable energy alternatives and efficiency improvements. / QC 20100727