Binderless fiberboard production from Cynara cardunculus and Vitis viniferaTwo lignocellulosic materials, Cynara cardunculus and Vitis vinifera, were pretreated and used to produce fiberboards without synthetic adhesives. The lignocellulosic materials were steam exploded through a thermo-mechanical vapor process in a batch reactor. After pretreatment the materials were dried, ground and pressed to produce the boards. The effects of pretreatment factors and pressing conditions on the chemical and physicomechanical properties of the fiberboards were evaluated and the conditions that optimize these properties were found. Response surface methodology based on a central composite design and multiple response optimization were used. The variables studied were: pretreatment temperature, pretreatment time, pressing temperature, pressing pressure, and pressing time. Binderless fiberboards produced from Cynara cardunculus stalks at the optimum conditions found fulfilled the European standards for boards of internal use. Nevertheless, binderless fiberboards produced from Vitis vinifera prunings at the optimum conditions found for this material did not completely met the European standards; modulus of rupture and internal bond values for these boards were lower than required minimums.Simultaneously, commercial Kraft lignin was reacted in an alkaline medium to enhance its adhesive properties. Chemical changes in reacted Kraft lignins that include ash content, Klason lignin, acid-soluble lignin and sugars were determined, as well as, structural characteristics of these lignins in terms of phenolic hydroxyl, aliphatic hydroxyl, methoxyl, carbonyl, Mw, Mn and polydispersity. The effects of reaction temperature and reaction time on lignin properties were studied using response surface methodology, and optimal reaction conditions were found.Two different types of Kraft lignin were used, alkali treated Kraft lignin and crude acid-washed Kraft lignin, as additives to enhance the physicomechanical properties of binderless fiberboards produced from Vitis vinifera to reach and overcome the European standards completely. At the end fiberboards produced with 20% of Vitis vinifera fibers replaced by crude acid-washed Kraft lignin were able to meet the European standards completely.This research work was an effort to reduce our dependency upon petroleum derivates, to diminish deforestation and to increase the use of renewable and biodegradable materials with the intention of preserving the environment and to encourage a sustainable development of our society. / Producción de Tableros de Fibras a partir de Cynara cardunculus y Vitis viniferaEn el presente estudio trozos Cynara cardunculus y Vitis vinifera fueron pretratados, y usados para producir tableros de fibras sin adhesivos sintéticos. Estos materiales lignocelulósicos se explotaron con vapor a través de un proceso termomecánico de vapor en un reactor por lotes. Después del pretratamiento el material fue secado, molido y prensado en caliente para producir los tableros. Se evaluaron los efectos de los factores del pretratamiento (temperatura de reacción y tiempo de reacción) y las condiciones de prensado (presión de prensado, temperatura y tiempo) sobre las propiedades químicas y físico-mecánicas de los tableros de fibras y se establecieron las condiciones que optimizan dichas propiedades. Las propiedades físico-mecánicas de los tableros de fibras que fueron estudiadas son: densidad, módulo de elasticidad (MOE), módulo de ruptura (MOR), enlace interno (IB), absorción de agua (WA) y hinchazón en hinchazón (TS) y las propiedades químicas estudiadas de la materia prima y el material pretratado fueron las siguientes: Cenizas, contenido de lignina Klason, contenido de celulosa y contenido de hemicelulosas. Se uso una metodología de superficie de respuesta basada en un diseño de experimentos del tipo central compuesto y una metodología de optimización de respuesta múltiple.Los tableros de fibras sin adhesivos sintéticos producidos a partir de tallos de Cynara cardunculus a las condiciones óptimas encontradas cumplieron con las normas europeas para los tableros de uso interno. Sin embargo, los tableros de fibras sin adhesivos sintéticos producidos a partir de podas de Vitis vinifera a las condiciones óptimas encontradas para este material no cumplieron totalmente las normas europeas; los valores del módulo de ruptura y del enlace interno para estos tableros fueron inferiores a los mínimos requeridos. Una lignina Kraft comercial fue sometida a reacción en un medio alcalino para mejorar sus propiedades adhesivas. Se determinaron los cambios químicos en las ligninas Kraft tratadas, las propiedades medidas fueron: contenido en cenizas, lignina Klason, lignina soluble en ácido y azúcares, también se determinaron las características estructurales de estas ligninas en términos de hidroxilos fenólicos, hidroxilos alifáticos, metóxilos, carbonilos, Mw, Mn y polidispersidad. Se estudiaron los efectos de la temperatura de reacción y el tiempo de reacción sobre las propiedades de la lignina con una metodología de superficie de respuesta, y se encontraron la condiciones óptimas de reacción.Se usaron dos tipos diferentes de lignina Kraft, lignina Kraft tratada en medio alcalino y lignina Kraft cruda lavada con ácido, como aditivos para mejorar las propiedades físico-mecánicas de los tableros de fibras sin adhesivos sintéticos producidos a partir de Vitis vinifera, para alcanzar y superar las normas europeas completamente. Al final los tableros de fibras producidos con una substitución del 20% de fibras de Vitis vinifera por lignina Kraft cruda lavada con ácido fueron capaces de satisfacer las normas europeas por completo.Este trabajo de investigación fue un esfuerzo para reducir nuestra dependencia de los derivados del petróleo, para disminuir la deforestación y para aumentar el uso de materiales renovables y biodegradables con la intención de preservar el medio ambiente y fomentar un desarrollo sostenible de nuestra sociedad.

En este trabajo se estudian los parámetros de obtención de tableros sin aporte de adhesivos, a partir de materiales lignocelulósicoscomo son la caña común (Arundodonax L.) y el bagazo de SaccharumofficinarumL. Los tableros propuestos aportan como ventaja el estar libres de emisiones de formaldehído y el no consumir recursos fósiles. Ambas propiedades son importantes en un mercado cada vez más exigente en aspectos medioambientales. En el caso del “ArundodonaxL” se ha partido de cañas silvestres de Tarragona. El bagazo de Saccharumofficinarum utilizado es el subproducto industrial de una destilería de la Isla de la Palma (Canarias). El material crudo ha sido pretratado realizando una “explosión de vapor” en un reactor “batch” a distintas condiciones de severidad. Este material explosionado se ha triturado y prensado en frío de dos formas (en seco y en húmedo). Posteriormente, los tableros prensados en frío y acondicionados a temperatura y HR constantes se han prensado en caliente a diferentes niveles de presión, temperatura y tiempo de prensado. En el proceso de producción a escala de laboratorio de los tableros, se han mejorado algunas de las fases seguidas como el prensado, introduciendo mallas de evacuación de vapor; y se han innovado otros, como la incorporación del prensado en frío y el tratamiento térmico final después de la conformación en caliente. Todo ello para mejorar la homogeneidad y obtener tableros de altas prestaciones mecánicas con estosmateriales. Se ha podido estudiar el efecto de los distintos factores que intervienen en la producción de tableros (Severidad del pretratamiento, temperatura de prensado, presión de prensado y tiempo de prensado), sobre las características físicas y mecánicas de estos tableros(Densidad, MOE, MOR, IB, TS y WA). Con ello se han obtenido las relaciones matemáticas que vinculan a estos factores de producción con las características físicas y mecánicas de los tableros. Puede ser muy importante para la industria el hecho de que los modelos ajustados definidos nos pueden permitir obtener tableros con características prefijadas. También se ha valorado la utilización de material integro explosionado y no lavado y, por tanto, sin ningún lixiviado ni residuo. Los tableros cumplen sobradamente los requerimientos de las norma EN para uso estructural, en todas las características físico-mecánicas estudiadas. Abreviaturas: HR Humedad relativa MOE Módulo de elasticidad en flexión o Módulo de Young MOR Módulo de rotura o Resistencia a la flexión IB Resistencia a la tracción perpendicular a las caras (Internal Bond) TS Hinchamiento WA Absorción de agua / This work studies the parameters for obtaining binderless fiberboards from lignocelullosic materials such as giant reed (Arundodonax L.) and sugar cane bagasse (Saccharumofficinarum L.) The suggested boards havethe advantage of being free from formaldehyde emissions and of not consuming fossil resources. Both properties are important in a market that is increasingly sensitivetowards environmental issues. Wild reeds from Tarragona were used as the base material to make Arundodonax Lfiberboards. The Saccharumoffinarumsugar cane bagasse was anindustrial byproduct obtained from a plantation on the island ofLa Palma in the Canary Islands (DestileríasAldea SL). The raw material was pre-treated by performing a “steam explosion” in a “batch” reactor. The exploded material was ground and cold-pressed in two ways (wet and dry). Subsequently, the cold-pressed boards, which had beenconditioned at a constant temperature and RH, were hot-pressed at different levels of pressure, temperature and press time. Some of the processes for producing boards on a laboratory-scale,such as pressing withsteam evacuation meshes, have been improved. Others processes were specifically developed in the laboratory, including the incorporation of cold-pressing and the final heat treatment after hot-forming. The aim of all this was to achieve high mechanical performance in boards made from these materials. Different factors involved in the production of the boards were studied (severity of pretreatment, pressing temperature, pressing pressure and pressing time) to determine how they affectthe physical and mechanical properties of these boards (density, MOE, MOR, IB, TS and WA). As a result, the mathematical relationships that link these production factors to the physical and mechanical properties of the boards were obtained. It is very significant for the industry that these adjusted models can produce boards with preset characteristics. The use of material that wascompletely exploded and unwashed and, therefore, without residue has also been studied. In terms of all the physical-mechanical characteristics studied,the boards fully comply with the requirements of the EN standards for structural use. Abbreviations RHRelativehumidity MOE Modulus of elasticity MOR Modulus of rupture IB Internal bond TS Thicknessswelling WA Water absorption

During the case of a hypothetical severe accident in a light water reactor, core damage may occur and molten fuel may interact with water resulting in explosive interactions. A Fuel-Coolant Interactions (FCI) consists of many complex phenomena whose characteristics determine the energetics of the interactions. The fuel melt initially undergoes fragmentation after contact with the coolant which subsequently increases the melt surface area exposed to coolant and causes rapid heat transfer. A substantial amount of research has been done to understand the phenomenology of FCI, still there are gaps to be filled in terms of the uncertainties in describing the processes such as breakup/fragmentation of melt and droplets. The objective of the present work is to substantiate the understanding in the premixing phase of the FCI process by studying the deformation/pre-fragmentation of melt droplets and also the mechanism of melt jet breakup. The focus of the work is to study the effect of various influential parameters during the premixing phase that determine the intensity of the energetics in terms of steam explosion. The study is based on numerical analysis starting from smaller scale and going to the large scale FCI. Efforts are also taken to evaluate the uncertainties in estimating the steam explosion loads on the reactor scale. The fragmented core is expected to form a porous debris bed. A part of the present work also deals with experimental investigations on the coolability of prototypical debris bed. Initially, the phenomenology of FCI and debris bed coolability is introduced. A review of the state of the art based on previous experimental and theoretical developments is also presented. The study starts with numerical investigation of molten droplet hydrodynamics in a water pool, carried out using the Volume Of Fluid (VOF) method in the CFD code ANSYS FLUENT. This fundamental study is related to single droplets in a preconditioning phase, i.e. deformation/pre-fragmentation prior to steam explosion. The droplet deformation is studied extensively also including the effect of the pressure pulse on its deformation behavior. The effect of material physical properties such as density, surface tension and viscosity are investigated. The work is then extended to 3D analysis as a part of high fidelity simulations, in order to overcome the possible limitations of 2D simulations. The investigation on FCI processes is then continued to the analysis on melt jet fragmentation in a water pool, since this is the crucial phenomenon which creates the melt-coolant pre-mixture, an initial condition for steam explosion. The calculations are carried out assuming non-boiling conditions and the properties of Wood’s metal. The jet fragmentation and breakup pattern are carefully observed at various Weber numbers. Moreover, the effect of physical and material properties such as diameter, velocity, density, surface tension and viscosity on jet breakup length, are investigated. After the fundamental studies, the work was extended to reactor scale FCI energetics. It is mainly oriented on the evaluation of uncertainties in estimating the explosion impact loads on the surrounding structures. The uncertainties include the influential parameters in the FCI process and also the code uncertainties in calculations. The FCI code MC3D is used for the simulations and the PIE (propagation of input errors) method is used for the uncertainty analysis. The last part of the work is about experimental investigations of debris coolability carried out using the POMECO-HT facility at KTH. The focus is on the determination of the effect of the bed’s prototypical characteristics on its coolability, in terms of inhomogeneity with heap like (triangular shape) bed and the radial stratified bed, and also the effect of its multi-dimensionality. For this purpose, four particle beds were constructed: two homogeneous, one with radial stratification and one with triangular shape, respectively. The effectiveness of coolability-enhanced measures such as bottom injection of water and a downcomer (used for natural circulation driven coolability, NCDC) was also investigated. The final chapter includes the summary of the whole work. / Under ett svårt haveri i en kärnkraftsreaktor kan en härdsmälta bildas och smältan växelverka på ett explosivt sätt med kylvattnet. En sådan FCI (Fuel-Coolant-Interaction) inbegriper flera fysikaliska processer vilkas förlopp bestämmer hur stor den frigjorda energin blir. Vid kontakt med vattnet fragmenteras först härdsmältan vilket i sin tur leder till att en större yta exponeras för kylvattnet och att värmeöverföringen från smältan snabbt ökar. Mycket forskning har ägnats åt att förstå vad som sker under en FCI men det finns fortfarande luckor att fylla vad beträffar t ex osäkerheter i beskrivningen av fragmentering av såväl smälta som enskilda droppar av smält material. Syftet med detta arbete är främst att underbygga en bättre förståelse av den inledande delen av en FCI genom att studera dels hur enskilda droppar av smält material deformeras och splittras och dels hur en stråle av smält material fragmenteras. Vi studerar särskilt vilka parametrar som mest påverkar den energi som frigörs vid ångexplosionen. Problemet studeras med numerisk analys med början i liten skala och sedan i full skala. Vi söker också uppskatta de laster som explosionen utsätter reaktorns komponenter för. En annan viktig fråga gäller kylbarheten hos den slaggansamling som bildas under reaktorhärden efter en FCI. Slagghögen förväntas ha en porös struktur och en del av avhandlingen redogör för experimentella försök som genomförts för att utvärdera kylbarheten i olika prototypiska slaggformationer. I avhandlingens inledning beskrivs de fysikaliska processerna under en FCI och kylningen av en slaggansamling. Det aktuella kunskapsläget på dessa områden presenteras också utgående från tidigare experimentella och teoretiska studier. Studierna i avhandlingen inleds med numerisk analys av hydrodynamiken för en enskild droppe smälta i en vattentank där VOF-metoden i CFD-programmet ANSYS FLUENT används. Denna grundläggande studie rör en enskild droppe under förstadiet till fragmentering och ångexplosion då droppen deformeras alltmer. Deformationen studeras ingående också med hänsyn tagen till inverkan av en tryckpuls. Inverkan av olika egenskaper hos materialet, som densitet, ytspänning och viskositet studeras också. Arbetet utvidgas sedan till en beskrivning i 3D för att undvika de begränsningar som finns i en 2D-simulering. Studierna av FCI utvidgas sedan till en analys av fragmentering av en stråle smälta i vatten. Detta är en kritisk del av förloppet då smälta och vatten blandas för att ge utgångstillståndet för ångexplosionen. Beräkningarna genomförs under antagande att kokning inte sker och med materialegenskaper som för Wood´s metall. Mönstret för fragmentering och uppsplittring studeras ingående för olika Weber-tal. Dessutom studeras effekten på strålens uppsplittringslängd av parametrar som diameter och hastighet för strålen samt densitet, ytspänning och viskositet hos materialet. Efter dessa grundläggande studier utvidgas arbetet till FCI-energier i reaktorskala. Här ligger tonvikten på utvärdering av osäkerheter i bestämningen av den inverkan explosionen har på omgivande konstruktioner och komponenter. Osäkerheterna inkluderar eventuell bristande noggrannhet hos såväl de viktiga parametrarna i FCI-processen som i själva beräkningarna. Den sista delen av arbetet handlar om experimentella undersökningar av slaggformationens kylbarhet som genomförts i uppställningen POMECO-HT vid avdelningen för kärnkraftsäkerhet på KTH. Vi vill bestämma effekten av formationens prototypiska egenskaper på kylbarheten. För detta ändamål konstruerades fyra olika formationer: två homogena, en med radiell variation i partikelstorlek och en med triangulär variation. Vi undersökte också hur förbättrad kylning kan uppnås genom att tillföra kylvatten underifrån respektive via ett fallrör (kylning genom naturlig cirkulation). I det avslutande kapitlet ges en sammanfattning av hela arbetet. / <p>QC 20150507</p>

Bioethanol is an appealing alternative to petroleum-based liquid fuel due to drivers such as environmental regulations and government mandates. Second generation lignocellulosic feedstocks are abundant, but their resistance to hydrolysis continues to be problematic. Different pretreatments have been proposed to increase cellulose reactivity. Softwood pine autohydrolyzed at different severities was subjected to further treatment to increase fibre reactivity. Liquid hot water is most effective at removing barriers, with the highest increase in sugar yield after enzymatic hydrolysis. Alkaline (NaOH) is found to be the worst option compared to dilute acid and organosolv. In addition, higher chemical concentrations and longer treatment times do not guarantee higher enzymatic hydrolysis yield. Process modifications such as fiber washing and multistage enzymatic hydrolysis are observed to be effective at increasing yield. However, more research is required to bring the enzymatic hydrolysis yield to a level where commercialization is feasible.

Bioethanol is an appealing alternative to petroleum-based liquid fuel due to drivers such as environmental regulations and government mandates. Second generation lignocellulosic feedstocks are abundant, but their resistance to hydrolysis continues to be problematic. Different pretreatments have been proposed to increase cellulose reactivity. Softwood pine autohydrolyzed at different severities was subjected to further treatment to increase fibre reactivity. Liquid hot water is most effective at removing barriers, with the highest increase in sugar yield after enzymatic hydrolysis. Alkaline (NaOH) is found to be the worst option compared to dilute acid and organosolv. In addition, higher chemical concentrations and longer treatment times do not guarantee higher enzymatic hydrolysis yield. Process modifications such as fiber washing and multistage enzymatic hydrolysis are observed to be effective at increasing yield. However, more research is required to bring the enzymatic hydrolysis yield to a level where commercialization is feasible.

Pellets from haylage, respectively hay were extruded in an extruder working with a high temperature according to the utility model CZ 21314 with different parameters. The researched parameters of extrusion with a constant time delay were a pressure extrusion and volatile solids. The highest production of methane (CH4) at a fermentation with the temperature 40 °C was monitored from the haylage with a content of the volatile solids 10,6 - 11 % by extrusion with the pressure 1,37 MPa. The highest production of CH4 at a fermentation with the temperature 50 °C was monitored from the haylage with a content of the volatile solids 13,5 - 16,7 % by extrusion with the pressure 1,37 - 1,66 MPa. A kontent of the volatile solids 11,5 % of haylage and extrusion with the pressure 1,35 ? 1,4 were estimated like optimum parameters for a fermentation with the temperature 40 - 50 °C with the highest production of CH4. For evaluation of the effectiveness of investment was used the metod of net present value (NPV). This method is the most commonly used and in most cases the most appropriate.

Devido às crises ocorridas no setor petroleiro, além do interesse em reduzir a emissão de gás carbônico (CO2), vários países buscam o desenvolvimento de novos combustíveis. Atualmente, mais de 80% da frota de veículos no Brasil rodam ou somente com etanol ou com uma mistura de etanol e gasolina. Desta forma, o bioetanol é considerado um combustível renovável alternativo com grande potencial para substituir os combustíveis oriundos do petróleo. Para atender a crescente demanda de etanol, sem competir com áreas cultiváveis voltadas para produção de alimentos, fontes de materiais lignocelulósicos podem ser utilizadas com o intuito de se aproveitar a fração celulósica para obtenção de açúcar fermentável para produção de bioetanol. Neste trabalho, o objetivo foi avaliar o efeito de tecnologias de pré-tratamento (convencionais e não convencionais) dos subprodutos sucroalcooleiros (bagaço e palha de cana), seguida ou não de uma etapa de deslignificação, sobre a conversão enzimática da celulose de cada biomassa vegetal, além de testar e avaliar o efeito que a mistura das duas biomassas (antes do pré-tratamento), em diferentes proporções, pode causar na produção de etanol 2G. Em uma primeira parte do trabalho, a palha de cana foi submetida ao pré-tratamento hidrotérmico e ao pré-tratamento por ultrassom, seguido de uma etapa de deslignificação alcalina. Para o pré-tratamento hidrotérmico, foram testadas três temperaturas (160, 170 e 180°C) nos tempos de 10, 20, 30, 40 e 50 min para cada temperatura. Para o teste com ultrassom, os experimentos foram conduzidos em três meios diferentes (ácido, alcalino e meio aquoso - controle) nos tempos de 1 a 30 minutos para cada condição. As amostras pré-tratadas por ultrassom e pelo método hidrotérmico foram deslignificadas com solução de NaOH 1%(m/v) por 1 hora. Após pré-tratamento e deslignificação, os ensaios de hidrólise enzimática foram realizados empregando Celluclast 1.5L (15 FPU/g de amostra) e ?-Glucosidase (12,5 UI/g de amostra). A condição de pré-tratamento hidrotérmico mais promissora para a palha foram a 170°C por 10 min, mostrando que a palha não necessita de tratamentos mais severos para obter uma maior digestibilidade no processo de hidrolise enzimática. Já o método por ultrassom provocou o aumento da recalcitrância do material lignocelulósico tanto para o agente deslignificante como para as celulases. Em uma segunda parte do trabalho, palha e bagaço de cana foram pré-tratados por explosão a vapor catalisado por SO2 nas seguintes condições para cada biomassa: 190, 195 e 200°C, por 5 min e 3% de SO2 (m/m). Após encontrar a condição ideal para ambas biomassas (190°C, 5 min, 3% SO2), três proporções diferentes de misturas de palha e bagaço foram testadas: 90% de palha / 10% de bagaço, 90% bagaço / 10% de palha e 50% de palha / 50% de bagaço e estas misturas foram prétratadas na condição otimizada. Em todas as etapas, a hidrólise enzimática foi realizada. Observou-se que a recuperação mais elevada de açúcar foi encontrada na amostra 50% bagaço/50% palha. Curiosamente, quando comparado com uma biomassa tratada isoladamente, todas as três misturas apresentam uma maior recuperação de açúcar. / Due to the crises in the oil sector, in addition to interest in reducing the emission of carbon dioxide (CO2), many countries seek to develop new fuels. Currently, over 80% of the vehicle fleet in Brazil only run on ethanol or a mixture of ethanol and gasoline. Thus, bioethanol is considered an alternative renewable fuel with great potential to replace petroleum derived fuels. To meet the growing ethanol demand, without competing with cultivable areas focused on food production, lignocellulosic materials sources can be used in order to take advantage of the cellulosic fraction to obtain fermentable sugar for bioethanol production. In this study, the objective was to evaluate the effect of pretreatment technologies (conventional and unconventional) of sugar and alcohol byproducts (bagasse and straw) followed or not by a delignification step on the enzymatic conversion of each biomass, besides test and evaluate the effect that mixing of the two biomasses (before pretreatment), in different proportions, can cause in the production of 2G ethanol. In the first part of the study, sugarcane straw was submitted to the hydrothermal pre-treatment and pre-treatment by ultrasound, followed by an alkaline delignification step. For the hydrothermal pretreatment, three temperatures were tested (160, 170 and 180°C) in the times of 10, 20, 30, 40 and 50 min for each temperature. For the test with ultrasound, the experiments were conducted in three different enviroments (acid, alkaline and aqueous medium - control) in the times of 1-30 minutes for each condition. The pretreated by ultrasound and by hydrothermal method samples were delignified with NaOH solution 1% (w/v) for 1 hour. After pre-treatment and delignification, the enzymatic hydrolysis assays were performed using Celluclast 1.5L (15 FPU/g of substrate) and ?-glucosidase (12.5 IU/g of substrate). The hydrothermal pretreatment condition most promising for the straw was at 170°C for 10 min, showing that the straw doesn\'t require more severe treatments to obtain a higher digestibility of the enzymatic hydrolysis process. Yet the ultrasound method led to increased recalcitrance of lignocellulosic material for both the delignificant agent as for cellulases. In a second part of the study, straw, and bagasse were pre-treated by steam explosion catalyzed by SO2 under the following conditions for each biomass: 190, 195 and 200°C for 5 min and 3% of SO2 (m/m). After finding the optimal condition for both biomasses (190°C, 5 min, 3% SO2), three different ratios of mixtures of straw and bagasse were tested: 90% straw / 10% bagasse, 90% bagasse / 10% straw and straw 50% / 50% bagasse and these mixtures were pretreated in the optimized condition. At all stages, the enzymatic hydrolysis was carried out. It was observed that the higher sugar recovery was found in the sample 50% bagasse / 50% straw. Interestingly, when compared with a treated biomass separately, all three blends exhibit a greater sugar recovery.

Med ett växande energibehov i världen, sinande energikällor i form av fossila bränslen och en miljö som vi under en längre tid har förorenat behövs det nya energiformer som är mer långsiktiga och framförallt miljövänliga. En sådan energiform är biogas. Biogasprocessen är dock inte helt optimerad. Flera av de substrat som används idag tar lång tid att röta och bryts bara ner till viss del i processen eller innehåller onödigt mycket vatten, vilket ger höga transportkostnader. Med syfte att göra biogasprocessen mer ekonomisk lönsam utvärderas i denna rapport på uppdrag från E.ON några olika förbehandlingstekniker: Ångexplosion, extrusion, avvattning och kalkbehandling. Förhoppningen är att dessa ska kunna öka lönsamheten för storskalig biogasproduktion och kanske möjliggöra biogasproduktion från tidigare obrukbara substrat som fjädrar och halm.  För att jämföra och utvärdera förbehandlingsteknikerna utfördes batchrötningsförsök i 330 ml flaskor med obehandlade och förbehandlade substrat. De flesta förbehandle substraten gav snabbare nedbrytning och några gav även högre metanutbyte än de obehandlade. Fjädrar och halm, som från början hade ett lågt utbyte, påverkades mest av förbehandlingen. Ångexploderade fjädrar gav efter 44 dagars rötning 141% högre metanutbyte och extruderad halm gav 22% högre metanutbyte än obehandlad.  För ekonomiska beräkningarna användes en referensanläggning med en förutbestämd substratmix: 12500 ton majs och 11500 ton hästgödsel. Att tillgå för referensanläggningen finns dessutom fjädrar. Cambis THP-anläggning för ångexplosion visade sig vara alldeles för dyr för referensanläggningen. En THP-anläggning kräver en större biogasanläggning där en större mängd svårnedbrytbara substrat rötas för att bli lönsam. En extruder skulle kunna vara lönsam för för refernsanläggningen om hästgödseln som de har tillgång till innehåller halm som strömaterial. En investering i en extruder bara för att förbehandla majsensilage visade sig inte lönsam.  Avvattning av gödsel gav signifikant lägre utbyte av biogas per torrvikt men signifikant högre utbyte per våtvikt. Avvattningsutrustningen från Splitvision, som testades, var för dyr för att bli lönsam. Först när gården låg 4 mil från biogasanläggningen blev det billigare att avvattna gödsel och transportera den jämfört med att transportera den obehandlad. Andra avvattningsutrustningar i studien var billigare i drift så det finns möjligheter att tekniken kan bli lönsam med någon av dessa. / The world needs new energy sources that are durable for long time and which not affect the environment negatively. Biogas fulfills those demands. The biogas process is however not completely optimized. Several of the substrates used today for biogas production are slowly degraded and only partly digested in the process. Other substrates consist of unnecessarily much water which makes transportation costly. To optimize the process and make the biogas process more profitable, several pretreatment techniques are evaluated by direction of E.ON in this report: steam explosion, extrusion, lime treatment and dewatering. The hope is that one of those could increase the profitability and hopefully also enable substrates that not are working today like feathers and straw. To compare and evaluate the different pretreatment batch digester, experiments were carried out during 31-44 days for untreated and pretreated substrates. Most pretreated substrates were faster degraded than untreated and some also gave a higher methane yield. Chicken waste feathers and wheat straw, which had low methane yields untreated, were affected most by pretreatment. Steam exploded feathers gave after 44 days of digestion 141% higher methane yield and extruded straw gave 22% higher methane yield than untreated samples of the same substrate. A reference plant with a substrate mixture of 12500 tonnes of maize silage and 11500 tons of horsemanure annually was used to make economical calculations. Additionally, chicken waste feathers waste could be included. Obtainable for the reference plant were also chicken waste feathers. Steam explosion appeared to be too expensive for a plant in the size of the reference plant. Its large capacity could probably make it profitable for a much larger biogas plant running on a lot of hard digestible substrates. An extruder could be a profitable investment for the reference plant if the plant gets horse manure with straw as bedding material. To just use the extruder to pretreat maize silage could not make the investment profitable. Dewatering of manure gave significantly lower methane yield per dry weight but significantly higher methane yield per wet weight. The increase in methane yield per wet weight makes the substrate better for transportation. The dewatering equipment from Splitvision tried in this study had too high operational costs and was too expensive to make dewatering particularly profitable. Only when the farm was situated farther away than 40km from the biogas plant it was cheaper to dewater the manure before transport than to transport the manure without any pretreatment. Other dewatering equipments evaluated in this study had much lower operational costs and among those an equipment that makes dewatering profitable might therefore be found. The world needs new energy sources that are durable for long time and which not affect the environment negatively. Biogas fulfills those demands. The biogas process is however not completely optimized. Several of the substrates used today for biogas production are slowly degraded and only partly digested in the process. Other substrates consist of unnecessarily much water which makes transportation costly. To optimize the process and make the biogas process more profitable, several pretreatment techniques are evaluated by direction of E.ON in this report: steam explosion, extrusion, lime treatment and dewatering. The hope is that one of those could increase the profitability and hopefully also enable substrates that not are working today like feathers and straw. To compare and evaluate the different pretreatment batch digester, experiments were carried out during 31-44 days for untreated and pretreated substrates. Most pretreated substrates were faster degraded than untreated and some also gave a higher methane yield. Chicken waste feathers and wheat straw, which had low methane yields untreated, were affected most by pretreatment. Steam exploded feathers gave after 44 days of digestion 141% higher methane yield and extruded straw gave 22% higher methane yield than untreated samples of the same substrate. A reference plant with a substrate mixture of 12500 tonnes of maize silage and 11500 tons of horsemanure annually was used to make economical calculations. Additionally, chicken waste feathers waste could be included. Obtainable for the reference plant were also chicken waste feathers. Steam explosion appeared to be too expensive for a plant in the size of the reference plant. Its large capacity could probably make it profitable for a much larger biogas plant running on a lot of hard digestible substrates. An extruder could be a profitable investment for the reference plant if the plant gets horse manure with straw as bedding material. To just use the extruder to pretreat maize silage could not make the investment profitable. Dewatering of manure gave significantly lower methane yield per dry weight but significantly higher methane yield per wet weight. The increase in methane yield per wet weight makes the substrate better for transportation. The dewatering equipment from Splitvision tried in this study had too high operational costs and was too expensive to make dewatering particularly profitable. Only when the farm was situated farther away than 40km from the biogas plant it was cheaper to dewater the manure before transport than to transport the manure without any pretreatment. Other dewatering equipments evaluated in this study had much lower operational costs and among those an equipment that makes dewatering profitable might therefore be found.

Devido às crises ocorridas no setor petroleiro, além do interesse em reduzir a emissão de gás carbônico (CO2), vários países buscam o desenvolvimento de novos combustíveis. Atualmente, mais de 80% da frota de veículos no Brasil rodam ou somente com etanol ou com uma mistura de etanol e gasolina. Desta forma, o bioetanol é considerado um combustível renovável alternativo com grande potencial para substituir os combustíveis oriundos do petróleo. Para atender a crescente demanda de etanol, sem competir com áreas cultiváveis voltadas para produção de alimentos, fontes de materiais lignocelulósicos podem ser utilizadas com o intuito de se aproveitar a fração celulósica para obtenção de açúcar fermentável para produção de bioetanol. Neste trabalho, o objetivo foi avaliar o efeito de tecnologias de pré-tratamento (convencionais e não convencionais) dos subprodutos sucroalcooleiros (bagaço e palha de cana), seguida ou não de uma etapa de deslignificação, sobre a conversão enzimática da celulose de cada biomassa vegetal, além de testar e avaliar o efeito que a mistura das duas biomassas (antes do pré-tratamento), em diferentes proporções, pode causar na produção de etanol 2G. Em uma primeira parte do trabalho, a palha de cana foi submetida ao pré-tratamento hidrotérmico e ao pré-tratamento por ultrassom, seguido de uma etapa de deslignificação alcalina. Para o pré-tratamento hidrotérmico, foram testadas três temperaturas (160, 170 e 180°C) nos tempos de 10, 20, 30, 40 e 50 min para cada temperatura. Para o teste com ultrassom, os experimentos foram conduzidos em três meios diferentes (ácido, alcalino e meio aquoso - controle) nos tempos de 1 a 30 minutos para cada condição. As amostras pré-tratadas por ultrassom e pelo método hidrotérmico foram deslignificadas com solução de NaOH 1%(m/v) por 1 hora. Após pré-tratamento e deslignificação, os ensaios de hidrólise enzimática foram realizados empregando Celluclast 1.5L (15 FPU/g de amostra) e ?-Glucosidase (12,5 UI/g de amostra). A condição de pré-tratamento hidrotérmico mais promissora para a palha foram a 170°C por 10 min, mostrando que a palha não necessita de tratamentos mais severos para obter uma maior digestibilidade no processo de hidrolise enzimática. Já o método por ultrassom provocou o aumento da recalcitrância do material lignocelulósico tanto para o agente deslignificante como para as celulases. Em uma segunda parte do trabalho, palha e bagaço de cana foram pré-tratados por explosão a vapor catalisado por SO2 nas seguintes condições para cada biomassa: 190, 195 e 200°C, por 5 min e 3% de SO2 (m/m). Após encontrar a condição ideal para ambas biomassas (190°C, 5 min, 3% SO2), três proporções diferentes de misturas de palha e bagaço foram testadas: 90% de palha / 10% de bagaço, 90% bagaço / 10% de palha e 50% de palha / 50% de bagaço e estas misturas foram prétratadas na condição otimizada. Em todas as etapas, a hidrólise enzimática foi realizada. Observou-se que a recuperação mais elevada de açúcar foi encontrada na amostra 50% bagaço/50% palha. Curiosamente, quando comparado com uma biomassa tratada isoladamente, todas as três misturas apresentam uma maior recuperação de açúcar. / Due to the crises in the oil sector, in addition to interest in reducing the emission of carbon dioxide (CO2), many countries seek to develop new fuels. Currently, over 80% of the vehicle fleet in Brazil only run on ethanol or a mixture of ethanol and gasoline. Thus, bioethanol is considered an alternative renewable fuel with great potential to replace petroleum derived fuels. To meet the growing ethanol demand, without competing with cultivable areas focused on food production, lignocellulosic materials sources can be used in order to take advantage of the cellulosic fraction to obtain fermentable sugar for bioethanol production. In this study, the objective was to evaluate the effect of pretreatment technologies (conventional and unconventional) of sugar and alcohol byproducts (bagasse and straw) followed or not by a delignification step on the enzymatic conversion of each biomass, besides test and evaluate the effect that mixing of the two biomasses (before pretreatment), in different proportions, can cause in the production of 2G ethanol. In the first part of the study, sugarcane straw was submitted to the hydrothermal pre-treatment and pre-treatment by ultrasound, followed by an alkaline delignification step. For the hydrothermal pretreatment, three temperatures were tested (160, 170 and 180°C) in the times of 10, 20, 30, 40 and 50 min for each temperature. For the test with ultrasound, the experiments were conducted in three different enviroments (acid, alkaline and aqueous medium - control) in the times of 1-30 minutes for each condition. The pretreated by ultrasound and by hydrothermal method samples were delignified with NaOH solution 1% (w/v) for 1 hour. After pre-treatment and delignification, the enzymatic hydrolysis assays were performed using Celluclast 1.5L (15 FPU/g of substrate) and ?-glucosidase (12.5 IU/g of substrate). The hydrothermal pretreatment condition most promising for the straw was at 170°C for 10 min, showing that the straw doesn\'t require more severe treatments to obtain a higher digestibility of the enzymatic hydrolysis process. Yet the ultrasound method led to increased recalcitrance of lignocellulosic material for both the delignificant agent as for cellulases. In a second part of the study, straw, and bagasse were pre-treated by steam explosion catalyzed by SO2 under the following conditions for each biomass: 190, 195 and 200°C for 5 min and 3% of SO2 (m/m). After finding the optimal condition for both biomasses (190°C, 5 min, 3% SO2), three different ratios of mixtures of straw and bagasse were tested: 90% straw / 10% bagasse, 90% bagasse / 10% straw and straw 50% / 50% bagasse and these mixtures were pretreated in the optimized condition. At all stages, the enzymatic hydrolysis was carried out. It was observed that the higher sugar recovery was found in the sample 50% bagasse / 50% straw. Interestingly, when compared with a treated biomass separately, all three blends exhibit a greater sugar recovery.

Förbehandling av lignocellulosa genom ångexplosion är en förbehandling av biomassa som förändrar strukturen i fibrernas cellväggar. Vid förbehandlingen värms biomassa med mättad ånga under tryck till minst 140 ˚C, detta leder till att flyktiga ämnen avgår från biomassan. När den uppvärmda biomassan är färdigbehandlad utsätts den för en kraftig trycksänkning vilket leder till att fukten i biomassan övergår till ånga och bidrar till ökad porositet, minskad materialstorlek och förändrad struktur i cellväggarna. Genom kartläggning av ett befintligt kokkärl på SCA R&amp;D Centre och litteraturstudier inom området utforskas möjligheten att bygga om kokkärlet till ångexplosionsreaktor för laborativt bruk. Ett utformningsförslag togs fram varpå en termodynamisk modell över reaktionen skapades i Excel med hjälp av makrot Xsteam. Dimensionering av blåstank till förslaget gjordes baserat på ångexplosion av två kg tallflis med två fukthalter, 40 och 60%. Resultaten visar att en ombyggnation är möjlig, ångpannan begränsar dock ångtrycket till 10 bar. Vid behandling av två kg tallflis med en fukthalt om 40 respektive 60% dimensionerades anläggningens blåstank till 376 respektive 493 liter. Den nya reaktorn designades som skild från atmosfären. En sådan reaktor möjliggör framtida analys av bland annat flyktiga ämnen vilket kan bidra till effektivare tillvaratagande av restströmmar. / Pretreatment of lignocellulose by steam explosion is an energy efficient method that alters the structure of the fiber cell walls. Biomass is heated with pressurized saturated steam during the pretreatment to at least 140˚C, causing the release of volatile substances. Once the heated biomass is treated to desired severity, it undergoes a significant pressure reduction, causing the moisture in the biomass to turn into steam and contribute to increased porosity, reduced particle size and altered structure in the fiber cell walls. By examining an existing digester at the SCA R&amp;D Centre and conducting literature studies in the field, the possibility of converting the digester into a steam explosion reactor for laboratory use is explored. A design proposal was developed, upon which a thermodynamic model of the reaction was created in Excel using the Xsteam macro. Dimensioning of the blow tank for the proposal was based on steam explosion of two kg pine chips with two moisture levels, 40% and 60%. The results indicate that such a conversion is possible, however, the steam pressure is limited to 10 bar overpressure due to the existing steam boiler. When treating two kg of pine chips with moisture content of 40% and 60% respectively, the sizing of the blow tank for the facility was determined to be 376 liters and 493 liters respectively. The new reactor was designed to be isolated from the atmosphere, enabling future analysis of volatile substances, which can contribute to a more efficient utilization of residual streams.