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Catalytic hydrotreating (HDT) is a mature process technology practiced in the petroleum refining industries to treat oil fractions for the removal of impurities (such as sulfur, nitrogen, metals, asphaltene). Hydrotreating of whole crude oil is a new technology and is regarded as one of the more difficult tasks that have not been reported widely in the literature. In order to obtain useful models for the HDT process that can be confidently applied to reactor design, operation and control, the accurate estimation of kinetic parameters of the relevant reaction scheme are required. This thesis aims to develop a crude oil hydrotreating process (based on hydrotreating of whole crude oil followed by distillation) with high efficiency, selectivity and minimum energy consumption via pilot plant experiments, mathematical modelling and optimization. To estimate the kinetic parameters and to validate the kinetic models under different operating conditions, a set of experiments were carried out in a continuous flow isothermal trickle bed reactor using crude oil as a feedstock and commercial cobaltmolybdenum on alumina (Co-Mo/γ-Al2O3) as a catalyst. The reactor temperature was varied from 335°C to 400°C, the hydrogen pressure from 4 to10 MPa and the liquid hourly space velocity (LHSV) from 0.5 to 1.5 hr-1, keeping constant hydrogen to oil ratio (H2/Oil) at 250 L/L. The main hydrotreating reactions were hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodeasphaltenization (HDAs) and hydrodemetallization (HDM) that includes hydrodevanadization (HDV) and hydrodenickelation (HDNi). An optimization technique is used to evaluate the best kinetic models of a trickle-bed reactor (TBR) process utilized for HDS, HDAs, HDN, HDV and HDNi of crude oil based on pilot plant experiments. The minimization of the sum of the squared errors (SSE) between the experimental and estimated concentrations of sulfur (S), nitrogen (N), asphaltene (Asph), vanadium (V) and nickel (Ni) compounds in the products, is used as an objective function in the optimization problem using two approaches (linear (LN) and non-linear (NLN) regression). The growing demand for high-quality middle distillates is increasing worldwide whereas the demand for low-value oil products, such as heavy oils and residues, is decreasing. Thus, maximizing the production of more liquid distillates of very high quality is of immediate interest to refiners. At the same time, environmental legislation has led to more strict specifications of petroleum derivatives. Crude oil hydrotreatment enhances the productivity of distillate fractions due to chemical reactions. The hydrotreated crude oil was distilled into the following fractions (using distillation pilot plant unit): light naphtha (L.N), heavy naphtha (H.N), heavy kerosene (H.K), light gas oil (L.G.O) and reduced crude residue (R.C.R) in order to compare the yield of these fractions produced by distillation after the HDT process with those produced by conventional methods (i.e. HDT of each fraction separately after the distillation). The yield of middle distillate showed greater yield compared to the middle distillate produced by conventional methods in addition to improve the properties of R.C.R. Kinetic models that enhance oil distillates productivity are also proposed based on the experimental data obtained in a pilot plant at different operation conditions using the discrete kinetic lumping approach. The kinetic models of crude oil hydrotreating are assumed to include five lumps: gases (G), naphtha (N), heavy kerosene (H.K), light gas oil (L.G.O) and reduced crude residue (R.C.R). For all experiments, the sum of the squared errors (SSE) between the experimental product compositions and predicted values of compositions is minimized using optimization technique. The kinetic models developed are then used to describe and analyse the behaviour of an industrial trickle bed reactor (TBR) used for crude oil hydrotreating with the optimal quench system based on experiments in order to evaluate the viability of large-scale processing of crude oil hydrotreating. The optimal distribution of the catalyst bed (in terms of optimal reactor length to diameter) with the best quench position and quench rate are investigated, based upon the total annual cost. The energy consumption is very important for reducing environmental impact and maximizing the profitability of operation. Since high temperatures are employed in hydrotreating (HDT) processes, hot effluents can be used to heat other cold process streams. It is noticed that the energy consumption and recovery issues may be ignored for pilot plant experiments while these energies could not be ignored for large scale operations. Here, the heat integration of the HDT process during hydrotreating of crude oil in trickle bed reactor is addressed in order to recover most of the external energy. Experimental information obtained from a pilot scale, kinetics and reactor modelling tools, and commercial process data, are employed for the heat integration process model. The optimization problem is formulated to optimize some of the design and operating parameters of integrated process, and minimizing the overall annual cost is used as an objective function. The economic analysis of the continuous whole industrial refining process that involves the developed hydrotreating (integrated hydrotreating process) unit with the other complementary units (until the units that used to produce middle distillate fractions) is also presented. In all cases considered in this study, the gPROMS (general PROcess Modelling System) package has been used for modelling, simulation and parameter estimation via optimization process.

Due to the vast fossil fuel wealth, the country of Saudi Arabia is experiencing a dramatic growth in both population and GDP. Therefore there is a growing demand for water and energy to meet these needs. All of the electricity that is generated is sourced from crude oil and natural gas. All natural gas production is used domestically and there are no net imports or exports. Due to many constrains on the natural gas supply, there is a slow shift in the generation mix going towards crude oil based power generation. This study assessed the viability of utility scale solar integration into the Saudi Arabian electric mix to potentially relieve some demand pressure for natural gas consumption as well as reduce green house gas emissions. Parabolic trough concentrated solar power technology was chosen as the primary technology for utility scale integration. A total of five scenarios were calculated. The scenarios include the following, base case, 5%, 10%, 15%, 20% solar integration in terms of installed capacity. Two sets of net present values were calculated. The net present values of each scenario were calculated. A second set of net present values was calculated with a projected increase in electricity prices. The natural gas and crude oil offset from the four solar integration scenarios were calculated using the base case forecasted natural gas and crude oil consumption from power generation. As expected, natural gas and crude oil consumption decreased when there was an increase in solar integration. The expected carbon dioxide offsets were calculated for each scenario. There was a decrease in carbon dioxide emission as solar integration was increased. Finally, all of these analyses were used as criteria for a decision analysis using the analytical hierarchy process. Depending on the decision maker’s importance on the determined criteria, solar integration in the Kingdom of Saudi Arabia is achievable. / text

My dissertation consists of three distinct but related chapters on Energy Economics and Finance. My first chapter is an empirical evaluation of market conduct in global crude oil markets. "Hotelling rule" states that even in competitive equilibrium, price of an "exhaustible resource" exceeds its marginal cost due to the opportunity cost of depleting the non-renewable resource. This cost is called "scarcity rent". Oil price exceeds its marginal extraction cost significantly. This can be attributed to two different sources: effect of scarcity of oil on prices or exercising market power by OPEC (collusion). In this paper, I use Porter (1983) approach considering the possibility of "scarcity rent" component involved in the gap between price and marginal extraction cost in the oil market. The novelty of my approach is to empirically estimate scarcity rent using data on cost of production of oil. Two benchmark cases, where scarcity rent is either zero (non-exhaustible resources hypothesis (Adelman 1990)) or equal to minimum price-cost margin are considered. The results show that in both cases OPEC failed to cooperate effectively and in second case, market conduct estimated is closer to Cournot behavior. In the second chapter of my dissertation, we employ a real options approach to evaluate oil and gas companies' investment decisions in an empirical setup. We develop a theoretical model to derive testable predictions. A unique measure of investment costs is obtained from energy industry data vendors. This novel dataset contains details of contract terms and pricing for offshore drilling equipment, which constitute the major share of investment costs in offshore oil field development. The investment database is combined with financial and macroeconomic data, which enables us to perform a panel data analysis of investments' response to variations in investment costs and market variables such as the slope of futures curve, firms' past earnings, cost of capital and implied oil price volatility. Our results show that the larger firms, facing less financial friction, are more forward looking while the smaller firms, who have less access to capital markets, are more dependent on their past earnings. The third chapter of my dissertation is about the effect of recent natural gas production boom on U.S. manufacturing. Natural gas production in North America has increased significantly over the past decade causing the prices to plunge during past 5 years. The purpose of this research is to investigate the effect of low natural gas prices on energy intensive U.S. manufacturing industries using market data. I empirically evaluate the stock market reactions of publicly traded companies in energy intensive industries to arrival of new information about the unexpected price shocks in natural gas futures markets. My results show that the stock market does not react significantly to innovations in the expected price of natural gas, proxied for by monthly changes in natural gas futures contracts with a fixed maturity date. I then split the sample into two groups based on their expenditure on natural gas as a ratio of their total production value. The stock market valuation of companies in high "natural gas intensity" industries were positively affected by unexpected downward shocks in natural gas prices and the results are significant. / text

The objective of this study is to develop a market sentiment model for financial markets using machine learning, and to illustrate these methods using commodity price data. A market sentiment model may capture the fundamental and crowd psychology of the market, through a variable that uses positive and negative words and phrases. The commodity price used is the daily price of the spot crude oil exchange-traded fund (ETF), United States Oil Fund (USO). The forecasting power of the market sentiment model is compared with a traditional autoregressive model. The results showed that the autoregressive models did not have significant forecasting power for the oil data over the time period examined and the addition of the sentiment model did not improve the forecasting power. Machine learning is a relatively new forecasting method. Therefore, further research on this topic is needed before any firm conclusions can be drawn regarding the effectiveness of this approach. / February 2017

Des nouveaux procédés éco-efficients basés sur une meilleure utilisation des ressources renouvelables sont nécessaires pour assurer la continuité du développement énergétique. La thèse étudie le procédé de gazéification en eau supercritique (T>374°C et P>22,1 MPa) de la biomasse très humide pour l’obtention de l’hydrogène, molécule ayant un potentiel énergétique très intéressant à valoriser avec un impact environnemental très favorable. L’étude porte sur l’application du procédé à la biomasse modèle (solutions de glucose, glycérol et leur mélange) ainsi qu’au bioglycérol, résidu de la fabrication du biodiesel. Les propriétés du solvant et les mécanismes prépondérants développés par l’eau en phase souset supercritique peuvent être contrôlés par les paramètres opératoires imposés au processus : température, pression, concentration en molécules organiques et catalyseur alcalin, temps de réaction... Les études paramétriques des systèmes réactionnels ont été menées dans des réacteurs batch à deux échelles différentes, les phases résultantes étant caractérisées par des protocoles analytiques élaborés et validés dans le cadre de l’étude. Le suivi du milieu réactionnel en batch lors de son déplacement vers l’état supercritique a mis en évidence une conversion avancée des molécules organiques et une identification de certains intermédiaires générés. Parmi les paramètres étudiés, la température et le temps de réaction influent le plus le rendement à l’obtention d’hydrogène en présence de catalyseur (K2CO3) dans les réacteurs batch, rendements de 1,5 et 2 mol d’H2 respectivement par mol de glycérol et de glucose introduites. Les gaz obtenus contiennent des proportions variables d’hydrocarbures légers et du CO2. Environ 75% du carbone est converti en phase gaz et liquide (sous forme de carbone organique et inorganique), le restant étant déposé sous forme solide ou huileuse. L’analyse du solide généré (plus de 90% de C) laisse apparaître différentes phases, y compris la formation de nanoparticules sphériques. Enfin, la gazéification en réacteur continu du glycérol préchauffé a montré de meilleurs rendements en hydrogène que le procédé batch, pendant que celle du bioglycérol demande une évolution du procédé à cause de la précipitation en phase supercritique des sels contenus dans le réactant. En conclusion, la gazéification en eau supercritique de la biomasse peut être considérée comme une alternative intéressante à d’autres procédés physico-chimiques de production de l’hydrogène. L’amélioration du procédé sera possible par son intensification menée en parallèle avec l’utilisation de matériaux plus performants et le contrôle de la salinité de la phase réactante. / Supercritical water (T > 374 ° C and P > 22.1 MPa) gasification of wet biomass for hydrogen production is investigated. This process converts a renewable resource into a gas, which is mainly composed of hydrogen and hydrocarbons with interesting energy potential, and which can be separated at high pressure. In addition, the greenhouse gas effect of the process is zero or negative. Model biomasses (glucose, glycerol and their mixture) and bio-glycerol, residue from bio-diesel production, have been gasified by different processes: two-scale batch reactors (5 mL and 500 mL) and a continuous gasification system. Supercritical water acts as a reactive solvent, its properties can be adjusted by the choice of the experimental (P, T) couple. The operating parameters, e.g. temperature, pressure, concentration of biomass and alkaline catalysts, reaction time… allow favoring certain reaction mechanisms. In order to characterize the processes, specific analytical protocols have been developed and validated. The intermediates, formed during the heating time in the batch reactors, have been identified. Among the investigated operating parameters, temperature and reaction time have the greatest influence on the hydrogen production in batch reactors. In the presence of catalyst (K2CO3), H2 yields of 1.5 mol/mol glucose and 2 mol/mol glycerol have been respectively observed. The obtained gas contains different proportions of light hydrocarbons and CO2. About 75% of the carbon is converted into gas and liquid (in form of organic and inorganic carbon). The conversion leads also to a solid or oily residue. In the generated solid phase (composed over 90% of C), spherical nanoparticles are observed via electronic microscopy. The hydrogen production from glycerol is improved in the continuous process compared to batch reactors, however, bio-glycerol supercritical water gasification requests process improvement due to the precipitation of the salt contained in the reactant. In conclusion, supercritical water gasification of biomass can be considered as an promising alternative process for hydrogen production. The process should be improved by more performing equipments and by the control of the salinity content of the crude biomass.

L'objectif de cette étude consiste à développer une approche permettant d'économiser de l'énergie de haut niveau thermique dans le procédé de la distillation atmosphérique du pétrole. Cette approche repose sur le fait que l'installation de plusieurs flashs sur le train de préchauffage de ce procédé associée à un choix approprié du plateau d'alimentation des vapeurs résultantes à la colonne de distillation, provoque une diminution de la chaleur apportée à ce train de préchauffage. Le déficit de chaleur de haut niveau thermique ainsi créé est causé par la réduction des débits des reflux latéraux de la colonne de distillation et il est compensé par de la chaleur de bas niveau thermique apportée par les effluents résiduaires disponibles dans toute la raffinerie. Cette approche peut être appliquée aux nouveaux procédés comme à l'expansion des procédés existants et l'économie d'énergie de haut niveau thermique dans le four peut atteindre les 21%. Une réduction équivalente des gaz à effet de serre est aussi observée / The objective of this thesis is to demonstrate, on thermodynamic grounds, that introducing a flash in the preheating train of an atmospheric oil distillation process , together with an appropriate feeding of the resulting vapors into the column, could potentially bring substantial energy savings by reducing the duty of the preheating furnace and by reducing the distillation column irreversibilities. This idea has been expended by showing how this can be done while keeping the throughput and the product characteristics unchanged. The outcome is that placing several flashes after the heat exchangers and feeding the corresponding vapor streams to the appropriate trays of the column, reduces the pumparound flows and then the heat brought to the preheating train. The resulting heat deficit may then be compensated in additional heat exchangers by using low level heat recuperated from the products of the distillation and/or imported from other processes. The use of this residual heat reduces the furnace duty by approximately an equivalent amount and could be as high as 21%. The approach can be applied in the design of news processes or in the revamping of existing ones

Ces travaux de thèse sur le fractionnement des produits pétrolier a pour but de mieux caractériser certaines espèces métalliques, principalement le Nickel et le Vanadium. Dans un premier temps, ils ont permis de démontrer que les composés contenant du V et Ni présents dans ces matrices complexes sont essentiellement concentrés dans les fractions les plus polaires, à savoir, les résines et les asphaltènes. En ce qui concerne les composés soufrés, on a constaté qu'ils se concentrent dans les fractions résines et les aromatiques. Il a également été constaté que la teneur en composés contenant du V et Ni qui précipite avec les asphaltènes est linéairement lié au paramètre de solubilité du solvant utilisé pour la précipitation. Et pour des solvants aux paramètres de solubilité proche de 16 MPa0.5, le pourcentage d’asphaltènes soluble est augmenté. On conclut que le pourcentage réel des asphaltènes présents dans un brut est égal au pourcentage d'asphaltènes insolubles, plus un pourcentage d’asphaltènes soluble. On a constaté que ces types d’asphaltènes ont une distribution de poids moléculaire similaire à celle des asphaltènes insolubles, et non un poids moléculaire plus faible. En ce qui concerne la distribution des poids moléculaires des composés du V présents dans les échantillons évalués, au moins trois grandes distributions de poids moléculaires ont été identifiées. Il s’agit des composés de « high molecular weight », « medium molecular weight » et « low molecular weight ». Sur ces distributions, nous trouvons que les composés contenant du V, Ni et S sont, dans les asphaltènes, prédominant dans la fraction HMW et sont caractéristiques des composés nanoagrégés. En ce qui concerne les composés de type MMW, ils ont été observés dans une plus grande proportion dans les maltènes. Il est à noter la présence de composés de type HMW avec les maltènes, ce qui pour les raisons exposées ci-dessus, peut être considérée comme une preuve incontournable de la présence d’asphaltènes soluble dans les maltènes. A propos des méthodes de séparation développées, il a été possible de séparer les différentes distributions de poids moléculaires initialement identifiées chez les maltènes et les asphaltènes. Pour les maltènes, il a été possible d’extraire les différents composés contenant du V et Ni en fonction de leur poids moléculaire HMW, LMW et MMW. Cette extraction a été réalisé en utilisant des extractions liquide-liquide des maltènes dissous dans de l'heptane avec de l’ACN pour extraire les composés à bas poids moléculaire, suivie par une extraction avec du DMF pour extraire des composés MMW. La fraction restante des maltènes est composés surtout de composés HMW.Pour les asphaltènes, 11 solvants ont été évalués pour l'extraction des composés contenant du V et du Ni. Le profil des composés extraits a permis de séparer jusqu'à 4 distributions différentes de poids moléculaire avec du ACN, de l’acétone et du DMF utilisés séquentiellement. En ce qui concerne les composés de HMW, la fraction insoluble après extraction au DMF a un poids moléculaire plus élevé que la fraction soluble. Pour l'influence de la concentration sur la présence des composés contenant du Ni et V de HMW, il a été démontré que même dilué 40.000 fois, une solution asphaltènes (à 25 mg / L) contient toujours des composés de HMW et donc des nanoaggregat d’asphaltènes. Quant à la caractérisation des fractions extraite, seule la fraction correspondant aux poids moléculaires faibles (LMW) a été étudiée. La détermination de la distribution du poids moléculaire par spectrométrie de masse FT ICR MS et la comparaison du chromatogramme par GPC ICP MS suggère que ces composés contenant du V et du Ni présent dans la fraction LMW sont des métalloporphyrines libre avec des structures brutes assez simples. Ces travaux vont permettre d’ouvrir la voie à une caractérisation plus approfondie des différentes fractions obtenus et ainsi de permettre une meilleure connaissance des pétroles lourds. / This PhD work were mainly dedicated to the fractionation of crude oil and petroleum products in order to better caracterize metals compounds (mainly V and Ni) in these complex matrices. It was determined that V and Ni compounds present in the crude oils and residues are concentrated mainly in their more polar fractions, that is to say, resins and asphaltenes. Concerning sulfur compounds, it was found that they are concentrate in the resins and aromatics fractions. All these results were similar to reported in the literature.It was also found the content of V and Ni compounds that precipitate together with the asphaltenes depends linearly of solubility parameter of solvent used for the precipitation of asphaltenes, so, for solvents with solubility parameters close to 16 MPa0.5, the percentage of asphaltene soluble increases. So it can be concluded the true percentage of asphaltenes present in the crude oil is equal to the percentage of insoluble asphaltenes plus the percentage of soluble asphaltenes. For this type of asphaltenes, it was found that they have a molecular weight distribution very similar to insoluble asphaltenes, and not a lower molecular weight, as originally thought (Speight and Mitchell, 1973).With respect to the distribution of molecular weights for the V compounds present in the samples evaluated, at least three molecular weight distributions were identified. Those were identified as compounds with high molecular weight (HMW), medium molecular weight (MMW) and low molecular weight (LMW) following the nomenclature previously reported in the literature. (Desprez et al., 2014).On these distributions, we has found that compounds of V, Ni and S with HMW predominate in the asphaltenes, which is characteristic of nanoaggregate compounds. With respect to the compounds with MMW, these were observed in a greater proportion in maltenes. It should be noted the presence of compounds with HMW in all maltenes evaluated, which for the reasons discussed above, can be considered an unavoidable evidence of the presence of soluble asphaltenes.With respect to the separation/extraction methods developed, it was possible to separate the different distributions of molecular weights initially identified in maltenes and asphaltenes. In the case of maltenes, for the first time in the literature it was possible to extract the various compounds of V and Ni present in these according to their molecular weight. For the separation in maltenes, liquid-liquid extractions on maltene dissolved in heptane were developed. So, with ACN, it has been possible to extract LMW compounds, while extractions with DMF allowed extracting MMW compounds, staying in the remaining maltene mostly compounds with HMW.For the asphaltene extraction, 11 solvents were evaluated. The study of profile obtained to each extract and remanent, allowed to pose a separation scheme that enabled to get up to 4 different molecular weight distributions. These were obtained with ACN, Acetone and DMF used sequentially. It is important to mention it was found that the insoluble fraction gotten with DMF had the highest molecular weight, even in comparison with the HMW asphaltenes soluble in DMF.With respect to the influence of the concentration on the aggregated compounds, it was found that this does not influence on the presence of compounds with HMW. Nanogregate were found in a solution of asphaltenes diluted 40,000 times (25 mg / L).Regarding the characterization of the extracted fractions, only the fraction corresponding to low molecular weights was studied. Determination of the molecular weight distribution by mass spectrometry and comparison of the GPC ICP MS chromatogram with a porphyrin standards, suggests that these V and Ni compounds present in LMW fraction has a structures quite simple. A deeper characterization will be presented in later work. / Se determinó que los compuestos de V y Ni presentes en los crudos y residuos evaluados se concentran principalmente en su fracciones más polares, es decir, resinas y asfaltenos. Con respecto a los compuestos de azufre, se encontró que los mismos se concentran en las resinas y aromáticos. Todos estos resultados fueron similares a lo reportado en la literatura. Igualmente se encontró que el contenido de compuestos de V y Ni que precipitan junto con los asfaltenos depende linealmente del parámetro de solubilidad del solvente usado para la precipitación de los asfaltenos, así para solventes con parámetros de solubilidad cercanos a 16 MPa0.5, el porcentaje de se asfalteno soluble incrementa, por lo que se puede concluir que el porcentaje verdadero de asfaltenos presente en el crudo es igual al porcentaje de asfaltenos insoluble más el porcentaje de asfaltenos solubles. Sobre este tipo de asfaltenos, se encontró que los mismos poseen una distribución de pesos moleculares muy similar a la de los asfaltenos insolubles, y no un peso molecular mucho menor, como se pensaba en un principio. Con respecto a la distribución de pesos moleculares para los compuestos de V presentes en las muestras evaluadas, se identificaron al menos tres grandes distribuciones de pesos moleculares. Las mismas se identificaron como compuestos con alto peso molecular o high molecular weight (HMW en inglés), medio peso molecular o medium molecular weight (MMW en inglés) y bajo peso molecular o low molecular weight (LMW por sus siglas en inglés) siguiendo la nomenclatura reportada previamente en la literatura. Sobre estas distribuciones, encontramos que en los asfaltenos predominan compuestos de V, Ni y S con HMW, el cual es característicos de compuestos agregados. Con respecto a los compuestos con MMW, estos fueron observados en mayor proporción en los maltenos. Es de hacer notar la presencia de compuestos con HMW en todos los maltenos evaluados, la cual por las razones antes expuestas, puede ser considerada una evidencia ineludible de la presencia de asfaltenos solubles. Con respecto a los métodos de separación desarrollados, fue posible la separación de las diferentes distribuciones de pesos moleculares inicialmente identificadas en los maltenos y asfaltenos. En el caso de los maltenos, por primera vez en la literatura fue posible separar los diversos compuestos de V y Ni en función de su peso molecular en HMW, MMW y LMW. La separación si hizo empleando extracciones líquido-líquido a maltenos disueltos en heptano con acetonitrilo para la extracción de compuestos con LMW, seguido de extracciones con dimetilformamida para la extracción de compuestos con MMW, quedando en el malteno remanente de la extracción, mayoritariamente compuestos con HMW. Para los asfaltenos, se evaluaron hasta 11 solventes en la extracción de compuestos de V y Ni. El perfil de los compuestos extraídos, permitió separar hasta 4 distribuciones de pesos moleculares diferentes con ACN, acetona y DMF usados secuencialmente. Con respecto a los compuestos con HMW, se encontró que la fracción insoluble con DMF presenta un mayor peso molecular que los asfaltenos con HMW solubles en estos. Con respecto a la influencia de la concentración en la determinación de compuestos con HMW la caracterización de los compuestos de V y Ni, los mismos fueron determinados aun en una solución de asfaltenos diluida 40.000 veces (25 mg/L). En lo referente a la caracterización de las fracciones separadas, solo fue estudiada inicialmente la fracción correspondiente a bajos pesos moleculares. En la misma, la determinación de la distribución de pesos moleculares por espectrometría de masa y la comparación en el cromatograma por GPC-ICP MS de estándares porfirínicos, sugiere que estos compuestos de V y Ni con LMW son metaloporfirinas simples presentes en el crudo con estructuras bastantes sencillas. Una caracterización más profunda será presentada en trabajo posteriores para esta y las demás fracciones.

O presente trabalho de pesquisa teve como objetivo principal avaliar o efeito da carga orgânica volumétrica aplicada (COVA) na produção de hidrogênio usando o reator AnSBBR com recirculação operado em batelada e biomassa imobilizada. Para este efeito, o reator foi operado a 30ºC com dois tempos de ciclo (3 e 4 h), alimentado com três concentrações afluentes (3000, 4000 e 5000 mgDQO.L-1), uma velocidade de recirculação de 30 L.h-1, usando glicerol como única fonte de carbono e a biomassa de uma estação de tratamento de abatedouro de aves. A combinação destes fatores fez com que o reator fosse operado com seis cargas orgânicas volumétricas aplicadas diferentes (7565, 9764, 12911, 10319, 13327 e 16216 mgDQO.L-1.d-1). Os resultados mostraram que não existiu uma tendência clara entre a carga orgânica aplicada e a produção de hidrogênio. Porém, os melhores resultados quanto à produção de hidrogênio foram atingidos quando o reator foi operado com 4 horas de tempo de ciclo e alimentado com uma concentração afluente de 5000 mgDQO.L-1 (COVA de 12911 mgDQO.L-1.d-1), sendo sua produtividade molar média de hidrogênio (PrM) de 67,5 molH2.m-3.d-1. Esta condição também atingiu o melhor rendimento molar de hidrogênio por carga orgânica aplicada RMCAS,m e o melhor rendimento molar de hidrogênio por carga orgânica removida (RMCRS,m), sendo estes de 5,2 e 21,1 molH2.kgDQO-1, respectivamente. Adicionalmente foi estudada a diferença na produção de hidrogênio entre o uso de biomassa pré-tratada e não tratada termicamente, cuja análise de variância (ANOVA) mostrou que a diferença não foi estatisticamente significativa. Finalmente o reator foi operado usando glicerina bruta industrial para comparar os resultados com aqueles obtidos operando com glicerol, observando-se uma clara desvantagem na produção de hidrogênio quando foi usada glicerina bruta. Em geral, o reator AnSBBR operado em batelada sequencial apresentou resultados promissores na produção de hidrogênio usando glicerol como fonte de carbono, porém estudos mais profundos ainda são necessários no intuito de otimizar o sistema para a utilização de glicerina bruta. / This study evaluated the influence of applied volumetric organic load on biohydrogen production in an anaerobic sequencing batch biofilm reactor (AnSBBR) with 3.5 L of liquid medium and treating 1.5 L of glycerin based wastewater per cycle at 30ºC. The reactor was operated with two cycle periods (3 and 4 hours), three influent concentrations (3000, 4000 and 5000 mgCOD.L-1), recirculation rate of 30 L.h-1 and an inoculum from a poultry slaughterhouse. Six applied volumetric organic loads (AVOLCT) were generated from the combination of cycle period and influent concentrations (7565, 9764, 12911, 10319, 13327 e 16216 mgCOD.L-1.d-1). There was not a clear relation between the applied volumetric organic load and hydrogen production. However, the highest hydrogen molar production (MPr: 67.5 molH2.m-3 .d-1) was reached when the reactor was operated with a cycle period of 4 h and an influent concentration of 5000 mgCOD.L-1 (AVOLCT: 12911 mgCOD.L-1. d-1). This condition also reached the highest molar yield per removed load based on organic matter (MYRLC,m: 5.2 molH2.kgCOD-1) and the highest molar yield per applied load based on organic matter (MYALC,m: 21.1 molH2.kgCOD-1). In addition, it was studied whether existed or not a statistical significant difference on molar productivity averages pre-treating and not pre-treating the inoculum. It was observed that this was not statistically significant (p>0.05). Finally, the reactor was operated using crude glycerol as a sole source of carbon to evaluate hydrogen production. The disadvantage on hydrogen production when crude glycerol was used comparing to pure glycerol was clearly observed. The AnSBBR used on hydrogen production experiments operated with pure glycerol as a sole carbon XIV source showed an important potential. Nevertheless, additional studies are required in order to optimize results.