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Production of high-quality syngas from biomass gasification in a dual fluidised bed gasifier (DFBG) has made a significant progress in R&D and Technology demonstration. An S&M scale bio-automotive fuel plant close to the feedstock resources is preferable as biomass feedstock is widely sparse and has relatively low density, low heating value and high moisture content. This requires simple, reliable and cost-effective production of clean and good syngas. Indirect DFBGs, with steam as the gasification agent, produce a syngas of high content H2 and CO with 12-20 MJ/mn3 heating value. The Mid Sweden University (MIUN) gasifier, built for research on synthetic fuel production, is a dual fluidised bed gasifier. Reforming of tars and CH4 (except for methanation application) in the syngas is a major challenge for commercialization of biomass fluidised-bed gasification technology towards automotive fuel production. A good syngas from DFBGs can be obtained by optimised design and operation of the gasifier, by the use of active catalytic bed material and internal reforming. This thesis presents a series of experimental tests with different operation parameters, reforming of tar and CH4 with catalytic bed material and reforming of tar and CH4 with catalytic internal reformer.   The first test was carried out to evaluate the optimal operation and performance of the MIUN gasifier. The test provides basic information for temperature control in the combustor and the gasifier by the bed material circulation rate.    After proven operation and performance of the MIUN gasifier, an experimental study on in-bed material catalytic reforming of tar/CH4 is performed to evaluate the catalytic effects of the olivine and Fe-impregnated olivine (10%wtFe/olivine Catalyst) bed materials, with reference to non-catalytic silica sand operated in the mode of dual fluidised beds (DFB). A comparative experimental test is then carried out with the same operation condition and bed-materials but when the gasifier was operated in the mode of single bubbling fluidised bed (BFB). The behaviour of catalytic and non-catalytic bed materials differs when they are used in the DFB and the BFB. Fe/olivine and olivine in the BFB mode give lower tar and CH4 content together with higher H2+CO concentration, and higher H2/CO ratio, compared to DFB mode. It is hard to show a clear advantage of Fe/olivine over olivine regarding tar/CH4 catalytic reforming.    In order to significantly reduce the tar/CH4 contents, an internal reformer, referred to as the FreeRef reformer, is developed for in-situ catalytic reforming of tar and CH4 using Ni-catalyst in an environment of good gas-solids contact at high temperature.  A study on the internal reformer filled with and without Ni-catalytic pellets was carried out by evaluation of the syngas composition and tar/CH4 content. It can be concluded that the reformer with Ni-catalytic pellets clearly gives a higher H2 content together with lower CH4 and tar contents in the syngas than the reformer without Ni-catalytic pellets. The gravimetric tar content decreases from 25 g/m3 down to 5 g/m3 and the CH4 content from 11% down below 6% in the syngas.   The MIUN gasifier has a unique design suitable for in-bed tar/CH4 catalytic reforming and continuously internal regeneration of the reactive bed material. The novel design in the MIUN gasifier increases the gasification efficiency, suppresses the tar generation and upgrades the syngas composition. / Gasification-based Biorefinery for Mechanical Pulp Mills

La conversion thermochimique de la biomasse en lit fluidisé circulant permet la production d’un gaz à haute valeur ajoutée, utilisable dans de nombreuses applications. L’objectif de ces travaux est de mieux comprendre et modéliser les phénomènes couplés, hydrodynamiques et réactifs, se déroulant en lit fluidisé circulant. Dans un premier temps, un pilote de pyrogazéification de 20 kg/h de biomasse en lit fluidisé circulant a été conçu. L’étude hydrodynamique de ce pilote a ensuite été réalisée entre 20 et 950 °C. Les résultats ont permis d’établir des règles de design et de fonctionnement de réacteurs de gazéification en lit fluidisé circulant. Dans un second temps, une étude de la pyrogazéification de la biomasse a été réalisée en lit fluidisé dense ainsi qu’en lit fluidisé circulant, entre 750 et 850 °C. L’étude de l’influence de nombreux paramètres opératoires (températures, pression partielle de la vapeur d’eau, débit de biomasse, débit de circulation, inventaire et nature du média, forme de la biomasse) sur les performances de la gazéification a permis d’identifier les paramètres clés permettant de contrôler la composition ainsi que le volume de gaz de synthèse produit. Par ailleurs, à partir des résultats expérimentaux, un schéma réactionnel est proposé pour la pyrolyse de la biomasse étudiée. Enfin, un outil de modélisation du réacteur de gazéification de la biomasse en lit fluidisé dense et circulant, intégrant les réactions de pyrolyse, de gazéification, de water-gas shift et de reformage des goudrons a été développé et validé sur les résultats expérimentaux. / The biomass thermochemical conversion in fast internally circulating fluidized bed (FICFB) allows producing a high-added value syngas that can be used in many end-use applications. This work aims to better understand and model the coupled phenomena, hydrodynamic and reactive, occurring in FICFB processes. In a first time, a 20 kg/h FICFB biomass pyrogasification pilot was designed and erected. Then, the hydrodynamic study of this pilot was carried out between 20 and 950 °C. Results led to propose some design and operation rules for FICFB gasifiers. In a second time, biomass pyrogasification was studied in a dense fluidized bed (DFB) as in a FICFB, between 750 and 850 °C. From the survey of the effect of numerous operating parameters (temperatures, steam partial pressure, biomass feeding rate, circulation flow rate, bed material inventory and nature, biomass shape) on the gasification performances, the key parameters for the control of produced syngas volume and composition were identified. Finally, a modelling tool of DFB and FICFB biomass gasifiers, integrating pyrolysis, gasification, water-gas shift and tars reforming reactions was developed and validated on the experimental results.

Este trabalho tem como objetivo a identificação da melhor rota para a produção de combustíveis e derivados sintéticos através do desenvolvimento e aplicação de uma ferramenta metodológica desenvolvida tendo como base ferramentas da qualidade: diagrama de afinidade, diagrama de relações e matriz causa-efeito. Estes diagramas foram adaptados para a análise e discussão dos fatores positivos e negativos de cada item da tríade considerada: insumo-processo-produto. A partir desta análise foram criadas as matrizes de causa-efeito, também separadas em fatores positivos e negativos para os insumos: gás natural (GN), biomassa e carvão mineral; para os processos: produção de gás de síntese (syngas) a partir do GN, gaseificação do carvão e a gaseificação da biomassa; e para os produtos: óleo lubrificante, óleo diesel, nafta, metanol e amônia. A análise destas matrizes causa-efeito gerou a matriz final, denominada matriz saldo, que permitiu a seleção da rota mais adequada para a produção de combustíveis e derivados sintéticos. Dentre os insumos estudados, o gás natural apresentou evidentes vantagens e, consequentemente, o processo a ser utilizado deve ser a produção do syngas a partir do GN, e dentre os produtos o metanol apresentou maiores benefícios para ser produzido. / This paper aims to present to identify of the best route for the production of fuels and synthetic derivatives through the development and application of a methodological tool based on quality tools: affinity diagram, relations diagram and matrices cause-effect. The diagrams have been adapted for the analysis and discussion of positive and negative factors of each item of the triad considered: feedstock-process-product. From the analysis, matrices of cause and effect were created and also, separated into positive and negative factors for the inputs: natural gas (NG), biomass and coal; for the processes: production of synthesis gas (syngas) from GN, coal gasification and biomass gasification; and for the products: lubricating oil, diesel fuel, naphtha, methanol and ammonia. The analysis of cause-effect matrices generated the final matrix, named balance matrix, which allowed the selection of the most suitable route for the production of fuels and synthetic derivatives. Among the input studied, NG presented remarkable advantages among the others. Therefore, the process to be used should be the production of syngas from NG. Among the products considered, methanol showed the best benefits to be produced.

Este trabalho tem como objetivo traçar um panorama geral da tecnologia de gaseificação ao longo da história. Inicialmente concebida para obter gás do carvão mineral e possibilitar uma iluminação pública mais eficiente, a gaseificação passou por várias fases. Na virada do século XIX para o XX, quando o town gas perdeu a iluminação pública para a eletricidade, a produção de gás passou a se voltar para aquecimento e cocção. Se novas possibilidades foram criadas a partir da descoberta da síntese de Fischer-Tropsch (que possibilitava a transformação do gás de síntese em líquidos que poderiam substituir combustíveis e matérias-primas para toda a cadeia petroquímica), a resolução dos problemas de logística do gás natural reduziu a importância do gás do carvão mineral também para o aquecimento e cocção. Crises de abastecimento de petróleo, o principal combustível do século XX, motivaram novas iniciativas e novas formas de utilização da gaseificação como, por exemplo, os gasogênios, que gaseificavam biomassa e carvão para movimentar veículos automotores especialmente durante a Segunda Grande Guerra. Já nos períodos de abundância de petróleo a tecnologia acabava por ser abandonada, uma vez que este era muito mais eficiente e conveniente. Na passagem do século XX para o século XXI, entretanto, as preocupações com as mudanças climáticas colocaram em cheque a contínua utilização de combustíveis fósseis entre os quais o petróleo. Nesse contexto abriu-se uma nova perspectiva para a gaseificação de biomassa, uma vez que esta, combinada com as possibilidades criadas pela síntese de Fischer-Tropsch, possibilitou a criação do conceito de biorrefinarias e de toda uma cadeia química a partir de matérias-primas não apenas renováveis, mas que também são residuais e não alimentares. Embora ainda haja desafios técnicos e, principalmente, econômicos a serem alcançados, outros desafios deste século além da questão climática -, os resíduos sólidos urbanos podem constituir-se em uma importante fonte de insumos para o processo de gaseificação. / This dissertation aims to deliver a systematic approach of the history of gasification process. Initially conceived to obtain coal gas to viabilize more efficient lighting for major cities, the gasification process has passed through several phases. During the Nineteenth Century, the town gas (the gas obtained from coal) has revolutionized night life in modern cities. At the turn of the Nineteenth Century, town gas lost public lighting to electricity, and gas from coal had to migrate to heating and cooking. New possibilities were created with the Fischer-Tropsch synthesis in the twenties. This process enabled the transformation of Syngas a product of the gasification process into any kind of hydrocarbon molecule. So, it could have been a useful substitute to oil, mainly during the oil supply crisis. The Twentieth Century was characterized by intense oil utilization in transport, mechanical forces, electricity generation and also creating products like plastic and asphalt. Gasification was seen as a very good alternative supply of raw material for these products, but in fact, the several oil supply crisis of the Twentieth Century were too short for make the gasification feasible. At the end of twentieth century another issue arose to boost gasification initiatives: climate change. Due the greenhouse effect and concerns about its consequences, researchers and companies started projects of biomass gasification to replace fossil fuels - which includes oil. So far, all these initiatives havent shown up as feasible in commercial production, but the opportunity to create a fossil oil substitute from non food raw materials still involves a lot of effort.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nickel-based catalysts with perovskite like structure have shown promising application in several catalytic reactions such as in the partial oxidation of methane to obtain syngas (H2 + CO). However, these properties are potentially influenced by synthesis methods, calcinations conditions (temperature, time and atmosphere) and substitutions of sites A and/or B in the structure. The effects of these variables have been studied with the aim of improving the performance of catalysts in the production of syngas and to avoid deactivation resulting from coke deposition. In the present study, nickel-based catalysts (LaNiO3) with perovskite like structure were prepared by polymeric precursors, chelating precursors and gel modified proteic methods. All samples were subjected to thermal treatment and then calcined at 700 °C (for 1 or 2 h) to obtain the targed phase. LaNiO3 catalysts calcined at 700 °C with the lowest content of chelating agents were supported on alumina. The resulting ceramic powders were characterized by X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, specific surface area, scanning electron microscopy and temperature programmed reduction tests. XRD patterns of the powders calcined at 700 °C showed the formation of perovskite phase in all samples. The characteristic peaks of perovskite phase were also found in the samples supported on alumina. Temperature programmed profiles of samples revealed the presence of two peaks with maximum at 368 °C and 482 °C. Calcined samples supported on alumina were used in the partial oxidation of methane to evaluate the level of CH4 conversion and selectivity to H2 and CO. LaNiO3 catalyst obtained through chelating precursor method showed the highest performance of methane conversion in the range of 50% and selectivity (about 60%), for 18 h of time reaction. / Os catalisadores a base de níquel com estrutura perovsquita têm se mostrado promissores na aplicação em diversas reações catalíticas, tal como, oxidação parcial do metano para obtenção de gás de síntese (H2 + CO). No entanto, as propriedades destes são potencialmente influenciadas pelo método de síntese, condições de calcinação (temperatura, tempo e atmosfera) e substituições dos sítios A e/ou B na estrutura. Os efeitos destas variáveis têm sido estudados, com o objetivo de aperfeiçoar o desempenho dos catalisadores na produção de gás de síntese e evitar a desativação destes por deposição de coque. No presente trabalho, catalisadores a base de níquel (LaNiO3) com estrutura perovsquita foram preparados através de três métodos: precursores poliméricos, precursores quelantes e gel proteico modificado. Todas as amostras foram submetidas a um tratamento térmico e, em seguida, calcinadas a 700°C (por 1 h ou 2 h) para obtenção da fase desejada. As perovsquitas do tipo LaNiO3 calcinadas a 700 °C com o menor teor de agentes quelantes foram suportadas em alumina. Os pós obtidos foram caracterizados por difratometria de raios X, espectroscopia na região do infravermelho, termogravimetria, área superficial específica, microscopia eletrônica de varredura e redução à temperatura programada. Os difratogramas dos pós calcinados a 700 °C mostraram a formação da fase perovsquita em todas as amostras. Nos difratogramas dos materiais suportados foram observados picos característicos da fase perovsquita e do suporte. Os perfis de redução à temperatura programada das amostras apresentaram dois picos de redução com máximos a 368 °C e 482 °C. As amostras calcinadas a 700 °C e suportadas em alumina foram testadas na reação de oxidação parcial do metano, sendo avaliados os respectivos níveis de conversão do metano e seletividade a CO e H2. Dentre os catalisadores estudados, o catalisador LaNiO3 obtido pelo método dos precursores quelantes e suportado em alumina foi o que apresentou maior nível de conversão de metano, na faixa de 50%, e maior seletividade ao H2 (aproximadamente 60%), durante 18 h de reação.

O presente trabalho se insere no Programa de Biomassa - Energia - Materiais - PROBEM?, cuja Refinaria de Biomassa desenvolve tecnologias para o aproveitamento integral de biomassas lignocelulósicas e oleosas, objetivando sua exploração autossustentada. Os principais produtos obtidos são combustíveis para geração de energia termoelétrica, produtos químicos, materiais inorgânicos e reciclagem de fertilizantes. Neste trabalho explorou-se a celulignina, que é um combustível obtido pela pré-hidrólise ácida da biomassa, visando à obtenção de gás de síntese (singás) da celulignina para geração de energia termoelétrica com turbinas a gás, como substituto do gás natural. Para essa aplicação, e também para aplicações em síntese de produtos químicos e combustíveis pelo processo Fischer Tropsch, teores de metais alcalinos, enxofre e cloretos são críticos. A biomassa considerada foi a madeira de Eucalyptus grandis. O trabalho propõe a lixiviação aquosa daqueles contaminantes por pré-hidrólise ácida da biomassa, seguida da moagem a úmido da celulignina para razões líquido/sólido (L/S) otimizadas em relação ao consumo de água e aos teores finais dos contaminantes na biomassa tratada. A eficiência da sequência de tratamentos foi verificada medindo os teores de potássio, sódio, cloreto e enxofre total após cada etapa de lixiviação da celulignina. A pré-hidrólise ácida do E. grandis foi realizada na presença de ácido sulfúrico como catalisador, com produção de cerca de 67% de celulignina e 34% de solução de açúcares, em relação à quantidade de biomassa seca inicial. Os resultados desta etapa do processamento mostraram uma redução no teor de potássio de 3,3 vezes e no teor de sódio de 1,9 vez na celulignina em relação ao E. grandis in natura. A celulignina assim obtida foi submetida a uma sequência de moagem a úmido em moinho de martelos. Resultados apontaram a razão L/S = 12 como mais eficiente. O singás obtido da celulignina apresentou teores estimados de K+ + Na+= 600 ppb, Cl-=1,4 mg/Nm³ e enxofre total = 4 mg/Nm³. Isso significa uma redução de 1000 vezes em K+ + Na+ em relação à biomassa bruta. Nessas condições, o gás de síntese obtido já seria similar ao singás do gás natural, podendo ser usado em turbinas a gás. As aplicações com o gás de síntese no processo Fischer Tropsch não estão descartadas já que as especificações do gás natural para essa mesma aplicação permitem um máximo de enxofre de 70 mg/Nm³. Melhoramentos nos procedimentos de análise química em todas as etapas do processo são necessários para levar a resultados mais acurados. Melhoramentos nos equipamentos de controle das emissões gasosas na geração do singás tendem a diminuir os teores de enxofre para os níveis previstos em norma (< 1mg/Nm³). / This work is part of the Program Biomass - Energy - Materials - PROBEM?, whose Biomass Refinery develops technologies for a self-sustaining exploration of lignocellulosic and oily biomass. The main products are fuels for thermal and electricity energy generation, chemicals, materials and recycled inorganic fertilizers. This work explores the cellulignin, which is a fuel obtained by acidic prehydrolysis of biomass aiming to produce synthesis gas (syngas) as a substitute for natural gas for themoelectrical energy generation with gas turbines. This application, and also for the Fischer Tropsch process, of alkali metals, sulfur and chlorine concentrations in the syngas must be very low. The selected biomass is Eucalyptus grandis. The main objectives are to promote the aqueous leaching of those contaminants from cellulignin by a sequence of treatments, and to obtain the syngas by gasification of the cleaned cellulignin. The aqueous leaching of contaminants is carried out by acidic prehydrolysis of the wood, followed by the wet grinding of cellulignin at different liquid / solid (L/S) rations optimized with respect to water consumption and the final concentration of contaminants in the treated biomass. The efficiency of the sequence of treatments was checked by measuring potassium, sodium, chloride and sulfur contents in the cellulignin after each leaching step. Prehydrolysis of E. grandis was carried out using sulfuric acid as a catalyst, producing 67% of cellulignin and 34% of hydrolysate in relation to the initial dry biomass mass. Results after prehydrolysis showed a reduction of 3.3 times in the potassium content and of 1.6 times for sodium in the unwashed cellulignin in relation to the E. grandis \'in natura\'. The cellulignin so obtained was wet-ground in hammer mill. Results showed the L/S = 12 as the more efficient ratio in the grinding step. After gasification of the cellulignin the estimated values of the contaminants in the syngas were K++Na+ = 600 ppb, Cl- =1,4 mg/Nm³, and total S = 4 mg/Nm³, similar to the syngas from natural gas specifications for those elements. This means that the syngas from the cellulignin can be used as a fuel in gas turbines, replacing the syngas obtained from natural gas. Yet, its application in the Fischer Tropsch process is not discarded because maximum sulfur content allowed in the natural gas for that application is 70 mg/Nm³. Improvements have to made on the analytical procedures to ensure more accurate results, and is also necessary to improve the efficiency of the equipments for gas emission control in the syngas generation process. The last improvement should lower the S content to the specification values for the syngas (< 1mg/Nm³).

Fossil fuel reserves are projected to be decreasing, and emission regulations are becoming more stringent due to increasing atmospheric pollution. Alternative fuels for power generation in industrial gas turbines are thus required able to meet the above demands. Examples of such fuels are synthetic gas, blast furnace gas and coke oven gas. A common characteristic of these fuels is that they are multi-component fuels, whose composition varies greatly depending on their production process. This implies that their combustion characteristics will also vary significantly. Thus, accurate and yet flexible enough combustion sub-models are required for such fuels, which are used during the design stage, to ensure optimum performance during practical operating conditions. Most combustion sub-model development and validation is based on Direct Numerical Simulation (DNS) studies. DNS however is computationally expensive. This, has so far limited DNS to single-component fuels such as methane and hydrogen. Furthermore, the majority of DNS conducted to date used one-step chemistry in 3D, and skeletal chemistry in 2D only. The need for 3D DNS using skeletal chemistry is thus apparent. In this study, an accurate reduced chemical mechanism suitable for multi-component fuel-air combustion is developed from a skeletal mechanism. Three-dimensional DNS of a freely propagating turbulent premixed flame is then conducted using both mechanisms to shed some light into the flame structure and turbulence-scalar interaction of such multi-component fuel flames. It is found that for the multi-component fuel flame heat is released over a wider temperature range contrary to a methane flame. This, results from the presence of individual species reactions zones which do not all overlap. The performance of the reduced mechanism is also validated using the DNS data. Results suggest it to be a good substitute of the skeletal mechanism, resulting in significant time and memory savings. The flame markers commonly used to visualize heat release rate in laser diagnostics are found to be inadequate for the multi-component fuel flame, and alternative markers are proposed. Finally, some popular mean reaction rate closures are tested for the multi-component fuel flame. Significant differences are observed between the models’ performance at the highest turbulence level considered in this study. These arise from the chemical complexity of the fuel, and further parametric studies using skeletal chemistry DNS would be useful for the refinement of the models.

Parmi les produits issus de la biomasse ou de la transformation des déchets organiques, le CO2 et le CH4 sont des intermédiaires chimiques importants qui ont de forts impacts environnementaux. En effet, ils sont les principaux gaz responsables de l'effet de serre et leur atténuation est un enjeu majeur. Une voie intéressante pour la valorisation de ces gaz est le reformage à sec du méthane (DRM), qui convertit le CO2 et le CH4 en gaz de synthèse (mélange d'hydrogène et de monoxyde de carbone). Ce mélange peut être utilisé pour plusieurs applications telles que la production de méthanol, d'éther diméthylique, d'hydrogène et des hydrocarbures liquides. Malgré cet intérêt, l'exploitation du DRM à l'échelle industrielle n'a pas encore vu le jour. La raison principale est la désactivation rapide des catalyseurs en raison des conditions sévères de fonctionnement du procédé (température élevée, dépôt de carbone). Cette thèse porte sur le développement de nouveaux catalyseurs à base de phosphate de calcium (CaP) dopés avec des métaux de transition pour la valorisation du CO2 et du CH4 en gaz de synthèse par DRM. Les CaP sont utilisés car ils possèdent des propriétés avantageuses en catalyse hétérogène comme la présence simultanée de sites acides et basiques, bonne stabilité thermique, large gamme de surface spécifique ... Dans un premier temps, des études sur les méthodes de synthèse de catalyseurs et sur la performance de différents métaux de transition (Zn, Fe, Co, Cu, Ni) ont été effectuées dans le but de sélectionner le catalyseur et sa méthode de préparation. Un réacteur à lit fixe capable de fonctionner à hautes température et pression a ensuite été testé pour un long temps de réaction afin d'évaluer correctement la performance des catalyseurs préparés. Ensuite, une étude paramétrique détaillée a été menée. L'influence des paramètres tels que le prétraitement des catalyseurs, la température (T = 400-700°C) et la pression (P = 1-25bar) de la réaction et les différents supports (hydroxyapatite, alumine) ont été étudiés. Enfin, la stabilité thermique et catalytique a été étudiée durant 300h de réaction. Les catalyseurs à base de CaP ont montré des rendements plus élevés en gaz de synthèse en comparaison aux catalyseurs commerciaux. Ces catalyseurs sont donc compétitifs dans les mêmes conditions opératoires (T = 700°C, P = 1bar, WHSV = 12272mLh-1gcat-1, t = 300h). Ce travail a montré l'intérêt des catalyseurs à base de CaP pour des processus à haute température, tel que le reformage à sec du méthane. / Among the products resulting from biomass or organic waste transformation, CO2 and CH4 are important chemical intermediates. They also have a strong environmental impact since they are primarily responsible for the greenhouse effect and their mitigation is a key issue. An attractive way of valorization of such gases is the dry reforming of methane (DRM), which converts CO2 and CH4 into syngas (mixture of hydrogen and carbon monoxide). This mixture can be used for several applications, such as the production of methanol, dimethyl ether, hydrogen and liquid hydrocarbons. Despite such interest, the exploitation of DRM on industrial scale has not emerged yet. The main reason is the rapid deactivation of the catalysts due to the severe operating conditions of the process (high temperature, carbon deposition). This thesis focuses on the development of new catalysts based on calcium phosphate (CaP) doped with transition metals for the valorization of CO2 and CH4 through DRM. Actually,CaP has advantageous properties in heterogeneous catalysis, as the simultaneous presence of acid and basic sites, good thermal stability, and wide range of surface area... Initially, a study on the catalyst synthesis methods and an investigation of the performance of different transition metals (Zn, Fe, Co, Cu, Ni) were carried out in order to select the catalyst system and the preparation method. Secondly, a fixed-bed reactor capable of operating at high temperature and pressure and for log time on stream was built and implemented during this work in order to properly evaluate the performance of the preparedcatalysts. Then, a detailed parametric study was conducted. The influence of parameters such as catalyst pre-treatment, temperature (T = 400-700°C) and pressure (P = 1-25bar) of the reaction and support (hydroxyapatite, alumina-based supports) were investigated. Finally, the catalytic stability was studied for 300h of time on stream (TOS). The CaP catalysts showing higher yields on syngas were compared to commercial catalysts. Our catalysts showed to be competitive in the same operating conditions (T = 700°C, P = 1bar, WHSV = 12272mLh-1gcat-1,TOS = 300h). This work shows the interest of CaP catalysts for high temperature process, such as dry reforming of methane.

The significance of bio fuels production is increasing as fossil fuels are being depleted and energy security is gaining importance in the final energy mix. Moreover, bio fuel production offers the potential to alleviate concerns regarding global warming and air pollution. The process scheme design and parameter value choices used in this analysis are exclusively based on research domain literature by considering the state of the art of pyrolysis technology. Henceforth, the results should not be interpreted as optimal performance of mature technology, but as the most likely performance given the current state of scientific knowledge. The purpose of this thesis is to study and assess the technical and economic models for the conversion of woody biomass to valuable biofuel products via fast pyrolysis. The mass rate of wood is considered as 100,000 t/y. Bio fuel production from pyrolysis is energy intensive process. Therefore, heat and energy requirement calculation for the process and optimum heat integration is necessary to improve the overall thermodynamic efficiencies for wood biomass pyrolysis. Three different cases are discussed in this thesis: 1. fast pyrolysis at 500 oC, 2. fast pyrolysis at 1000 oC   and 3. Slow pyrolysis at 500 oC.    Literature study was conducted for different pyrolysis processes and based on their findings and results a model was developed on excel for the calculation of mass and energy balance. Mass balance results shows that the process can be selected on the basis of final product required. It was found that fast pyrolysis at 500 oC is used when bio oil is the priority product, for maximizing the syngas yield fast pyrolysis at high temperature 800-1000 oC is preferred. Similarly slow pyrolysis is used for maximizing bio char yield. It was also found that raw material type and its pretreatment also has strong influence on the pyrolysis process and final composition of bio fuels. Heat flux and energy streams for the pyrolysis scheme are also designed and syngas was selected to fulfil the heat requirements for different processes alongside with pyrolysis such as drying and grinding. It was found out that syngas combustion and heat recovery from the condenser will be able to fulfill the heat demand for pyrolysis process. However the specific heat requirement for fast and slow pyrolysis process varies. According to the calculations heat flux requirement for slow pyrolysis is higher than the fast pyrolysis. An explanation for this variability of the heat for wood pyrolysis is exothermic primary char formation process competing with an endothermic volatile formation process which makes it as overall endothermic process. But pretreatment of wood or biomass in fast pyrolysis is extra burden on the total heat demand for fast pyrolysis. Economic assessment for the pyrolysis plants is also conducted through literature survey of already installed plants and it was found out that pyrolysis is more feasible for large production facilities. The trends shows that capital costs increase with the increase of plant size but the capital cost curve moves towards a straight line after reaching the certain value the production cost per gallon of bio fuel decreases with the increase of plant capacity. The cost of biofuel is extremely sensitive to variations in operating cost (for example, cost of feed stock such as wood and selling price of products) but is not significantly affected by the variations in capital cost.