This study investigated hydrogen produced from feeding three types of biomass wastes (rice straw, banyan leaves, and dry algae) into the microwave plasma system. When operating the microwave plasma system atmospherically (including 12SLM of central and vortex air flow at a power of 800W, 900W, or 1000W), different feeding methods were adopted, and the researchers measured the concentration of hydrogen and other gas products, calculated the conversion rate, and evaluated the feasibility of the technique. For feeding rice straws into the microwave plasma system at 800W, 900W, and 1000W using the upstream method, the concentrations of the produced hydrogen were 47.92%, 52.66%, and 56.08%, respectively. For feeding rice straws using the downstream method, the concentrations of the produced hydrogen were 33.65%, 40.15%, and 45.39%, respectively. For feeding banyan leaves using the upstream method, the concentrations of the produced hydrogen were 40.61%, 48.63%, and 52.82%, respectively. For feeding banyan leaves using the downstream method, the concentrations of the produced hydrogen were 34.08%, 37.97%, and 40.52%, respectively. For feeding dry algae using the upstream method, the concentrations of the produced hydrogen were 36.75%, 41.34%, and 45.13%, respectively. For feeding dry algae using the downstream method, the concentrations of the produced hydrogen were 30.80%, 33.20%, and 37.58%, respectively. This data indicates that the upstream feeding method is better than the downstream one for hydrogen production, and an increase of power can enhance the production of hydrogen. The most optimum hydrogen production was achieved when rice straws were fed into the system using the upstream method at a power of 1000W; each gram of rice straws produced about 40.47mg of hydrogen (conversion rate = 67.45%). For banyan leaves and dry algae, 40.40mg (conversion rate = 67.33%) and 31.46mg (conversion rate = 52.43%) of hydrogen were produced respectively. For other gas products, no CH4 was produced in this study because most of the produced CH4 from microwave plasma conversion had reacted with CO2 and produced CO and H2. The study also revealed that the concentration of CO2 decreased as the power decreased, and this drop of concentration was more apparent in the upstream feeding method than in the downstream method. Nevertheless, the result from t-test suggested that the different CO2 concentration at different power was not statistically significant. SWOT analysis was performed to examine the feasibility of using microwave plasma atmospherically for converting biomass wastes to hydrogen, and the result revealed that internally, the emphasis should be placed on the quality and quantity of products, as well as the techniques and performance, while externally, economy, policies, and energy sources should be the focuses.

Ce mémoire traite de la carbonisation de différents déchets de biomasse par pyrolyse douce dans une première étape. Dans une seconde étape, les charbons produits ont été activés à la vapeur d'eau. Six essences de bois (charme, chêne, douglas, épicéa de Sitka, hêtre et peuplier) ont été carbonisées et l'activation a été étudiée sur 4 essences (chêne, douglas, épicéa et peuplier). La première partie de ce mémoire consiste en une étude bibliographique sur la biomasse et sa valorisation énergétique, la production de charbons et l'activation. La deuxième partie de ce rapport présente les résultats expérimentaux relatifs à la carbonisation. Lorsque la carbonisation est complète, on peut corréler les principales propriétés physiques des charbons produits à partir des propriétés initiales du bois anhydre. Les modifications anatomiques induites par la carbonisation ont été expliquées à partir de mesures sur un porosimètre à mercure et d'observations au microscope électronique. Dans la troisième partie, les charbons obtenus à partir des 4 essences citées ont été activés à la vapeur d'eau à 800 °C pendant une heure. Les principales propriétés physiques caractérisant les charbons activés ont été déterminées. L'adsorption du phénol en phase aqueuse a été étudiée et les isothermes de sorption à 25 °C ont été décrites. L'étude des transferts de matière a montré que l'adsorption du phénol pouvait être caractérisée par un coefficient global de transfert de matière. Pendant l'adsorption, trois étapes limitantes successives ont été observées pendant lesquelles le coefficient global de transfert de matière est assez constant et dont la valeur est divisée par un facteur 10 à chaque changement d'étape / This report concerns the carbonization of different biomass wastes by soft pyrolysis in a first part. In a second part, the charcoals produced have been activated by water vapor. 6 wood species (ash, oak, douglas, Sitka spruce, beech and poplar) have been carbonized and the activation has been investigated on 4 wood species (oak, douglas, spruce and poplar). The first chapter of this report consists in a bibliographical study on biomass, its energetic valorization, production of charcoals and their activation. The second chapter of this report presents the experimental results concerning the carbonization. When the carbonization is complete, the main physical properties of the charcoals produced can be correlated to the initial properties of oven dry woods. The anatomic changes induced by pyrolysis have been explained from measurements performed on a mercury porosimeter and observations on an electronic microscope. In the third chapter, charcoals produced from the 4 wood species cited have been activated with water vapor at 800 °C during 1 hour. The main physical parameters characterizing the activated carbons have been determined. The adsorption of phenol in an aqueous phase has been investigated and the isotherms of sorption at 25 °C have been described. The study of mass transfers shows that the adsorption of phenol can be characterized by a global mass transfer coefficient. During the adsorption, 3 successive limiting steps have been observed. For each step, the mass transfer coefficient is quite constant but its value is divided by about 10 after each change of step

Il concetto di rete dell'informazione può diventare uno schema logico con cui descrivere l'evoluzione delle politiche sulle energie rinnovabili e sulla sostenibilità? La ricerca è stata svolta analizzando l'architettura delle due reti (internet e reti energetiche) e l'evoluzione del bene prodotto e distribuito nella rete energetica, l'energia, esplicitando l'accessibilità da parte della distribuzione mondiale delle risorse petrolifere tradizionali e delle risorse rinnovabili. La struttura metodologica del progetto di ricerca si basa due tipi di analisi teorica: 1) l'analisi della nascita delle società in rete attraverso le teorie di Manuel Castells (concetto di spazio di flussi) e di Saskia Sassen e l'evoluzione delle città (cap.2 e cap.5) 2) le analisi dei flussi dei materiali e delle energie avendo come riferimento metodologico l'approccio ecologico ideato dai ricercatori dell'istituto per il Clima, l'Ambiente e l'Energia di Wuppertal, Germania (cap.3 e cap.4) La contraddizione tra città innovative e città che sono ai livelli di enormi discariche o di baraccopoli è esposta nel cap.6 attraverso casi studio e progetto dei Programmi Europei. Nell'ultimo capitolo (cap.7) si riassumono le ipotesi di partenza e i risultati della ricerca e si espongono le questioni aperte. / Can internet logic scheme be used as a basis to describe public policies evolution on renewable energies production and sharing in urban areas all over the world? The research project analyses the two networks (internet and energetic grids) architectures in actual and future urban areas. This analysis is connected with present and future forecasts energy productions from traditional fuels and from renewable sources. Theoretical analysis is conducted following a double conceptual pathway: - societal networks (Manuel Castells theory) and urban areas evolution (Saskia Sassen and Mike Davis) in order to picture the evolution of cities and towns in modern economies and in developing countries (Chapters 2 and 5); - Material and Energy Flow Analysis (approach by Wuppertal Institute for Climate, Environment and Energy) applied to renewable energy (Chapters 3 and 4) In Chapter 6 case studies are exposed on the deep cleavage between two different worlds: innovative, rich towns on a side and the landfills cities, slums on the other side. In the last part hypothesis and thesis are put together and open questions are explained (Chapter 7).