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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Factibilidad constructiva de viviendas con muros portantes de fardos de paja energéticamente eficientes y sismo resistentes en la zona andina del Ecuador

Viera Arroba, Luisa Paulina 01 September 2023 (has links)
[ES] La Constitución del Ecuador establece que el acceso a una vivienda digna es un derecho fundamental. Sin embargo, muchos ciudadanos viven en situaciones de riesgo, ya que las edificaciones que habitan no tienen características físicas y/o estructurales adecuadas. Esto se acentúa en la zona rural, en donde la necesidad de casas que cumplan estándares de calidad es en promedio 71, 2% más que las ciudades. En la mayoría de construcciones que se realizan en Ecuador, se usan materiales convencionales como el hormigón, bloques y ladrillos. Por lo que, cubrir la totalidad del déficit de vivienda (665 612 unidades) requiere una gran inversión económica; además, del alto costo ambiental que representaría; ya que, los materiales mencionados tienen consumos energéticos altos desde su producción hasta su puesta en obra. Es evidente entonces que la dotación de vivienda debe hacerse con materiales sustentables y accesibles a la mayoría de la población. Una alternativa es la paja, que es natural, renovable, sumidero de CO2 y biodegradable. En Ecuador se obtienen anualmente 28 754,492 toneladas de paja de trigo y cebada. Con este desecho de la cosecha, se podrían hacer fardos, con los cuales construir casas. Sin embargo, en el país existe muy poco conocimiento de este material y el sistema constructivo que se requiere para edificar de forma técnica y segura. La presente investigación aborda la caracterización física y mecánica de los fardos producidos localmente para determinar su posibilidad de su uso como material de construcción. Además, se realizaron ensayos pseudo-dinámicos a muros portantes realizados con fardos y recubiertos con dos alternativas de mortero. Con los resultados obtenidos, se realizó la modelación estructural de una vivienda tipo, determinando que el desplazamiento lateral relativo de la misma, cumple los estándares de la Norma Ecuatoriana de la Construcción para edificaciones sismo resistentes. También se realizó un análisis económico, determinando que el costo de la vivienda tipo es inferior al valor establecido para casas de interés social en el país. Lo que determina su accesibilidad al segmento poblacional más pobre. Además, se elaboró un manual, que detalla el procedimiento constructivo de la casa tipo, de forma clara y sencilla para hacerlo de fácil entendimiento. / [CA] La Constitució de l'Equador estableix que l'accés a un habitatge digne és un dret fonamental. No obstant això, molts ciutadans viuen en situacions de risc, ja que les edificacions que habiten no tenen característiques físiques i/o estructurals adequades. Això s'accentua en la zona rural, on la necessitat de cases que complisquen estàndards de qualitat és en mitjana 71,2% més que les ciutats. En la majoria de construccions que es realitzen a l'Equador, s'usen materials convencionals com el formigó, blocs i rajoles. Pel que, cobrir la totalitat del dèficit d'habitatge (665 612 unitats) requereix una gran inversió econòmica; a més, de l'alt cost ambiental que representaria; ja que, els materials esmentats tenen consums energètics alts des de la seua producció fins a la seua posada en obra. És evident llavors que la dotació d'habitatge ha de fer-se amb materials sustentables i accessibles a la majoria de la població. Una alternativa és la palla, que és natural, renovable, embornal de CO2 i biodegradable. A l'Equador s'obtenen anualment 28 754,492 tones de palla de blat i ordi. Amb aquesta deixalla de la collita, es podrien fer fardells, amb els quals construir cases. No obstinate això, al país existed molt poc coneixement d'aquest material I el sistema construction que es required per an edificar de manera tècnica I Segura. La present investigació aborda la caracterització física i mecànica dels fardells produïts localment per a determinar la seua possibilitat del seu ús com a material de construcció. A més, es van realitzar assajos pseudo-dinàmics a murs portants realitzats amb fardells i recoberts amb dues alternatives de morter. Amb els resultats obtinguts, es va realitzar el modelatge estructural d'un habitatge tipus, determinant que el desplaçament lateral relatiu d'aquesta, compleix els estàndards de la Norma Equatoriana de la Construcció per a edificacions sisme resistents. També es va realitzar una anàlisi econòmica, determinant que el cost de l'habitatge tipus és inferior al valor establit per a cases d'interés social al país. El que determina la seua accessibilitat al segment poblacional més pobre. A més, es va elaborar un manual, que detalla el procediment constructiu de la casa tipus, de manera clara i senzilla per a fer-ho de fàcil enteniment. / [EN] The Constitution of Ecuador establishes that access to decent housing is a fundamental right. However, many citizens live in risky situations since their buildings do not have adequate physical and structural characteristics. This is accentuated in rural areas, where the need for houses that meet quality standards is, on average, 71.2% higher than in the cities. In most constructions in Ecuador, conventional materials such as concrete, blocks, and bricks are used. Therefore, covering the entire housing deficit (665 612 units) requires a significant economic investment, in addition to the high environmental cost, since the materials have high energy consumption from production to installation. It is evident then that housing must be built with sustainable materials accessible to most of the population. One alternative is straw, which is natural, renewable, a CO2, and biodegradable. In Ecuador, 28 754.492 tons of wheat and barley straw are obtained annually. With this waste from the harvest, bales could be made with which to build houses. However, there needs to be more knowledge of this material and the construction system required to build technically and safely in the country. The present research addresses the physical and mechanical characterization of locally produced bales to determine the possibility of their use as a construction material. In addition, pseudo-dynamic tests were carried out on load-bearing walls made with bales. An economic analysis was also carried out, determining that the cost of the house type is lower than the value established for houses of social interest in the country. This determines its accessibility to the poorest segment of the population. In addition, a manual was prepared detailing the construction procedure of the house type clearly and straightforwardly to make it easy to understand. / Viera Arroba, LP. (2023). Factibilidad constructiva de viviendas con muros portantes de fardos de paja energéticamente eficientes y sismo resistentes en la zona andina del Ecuador [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/196654
242

Comparing the Ignitability of Mulch Materials for a Firewise Landscape

DeGomez, Tom, Rogstad, Alix, Schalau, Jeff, Kelly, Jack 09 1900 (has links)
5 pp. / Eight different landscape mulches were tested for their flammability using a propane torch, charcoal briquette, and a cigarette at two different times of the year. Three randomized compete blocks with eight one square meter plots were tested at three locations; Tucson, Prescott, and Flagstaff, Arizona. Each of the mulches was subjected to the heat of a handheld propane torch (15 seconds), a glowing charcoal briquette (five minutes), and a lit cigarette (until burned out). We found that the least dense mulches (pine needles and straw) burned rapidly when subjected to the torch and ignited after the briquette was removed. The medium density mulches (pine bark nuggets and wood chips) had low flame lengths and smoldered. Heavy density mulches (garden compost and shredded bark) only smoldered. The decomposed granite and sod did not ignite or smolder.
243

Structural Testing of Compressed Earth Blocks and Straw Bale Panels

Tattersall, Graham 30 October 2013 (has links)
Globally, there is a need for alternative building materials that require less energy to produce than conventional materials. These alternative materials have gained popularity in recent years, however there is a need to better understand their physical properties in order to increase confidence in their use. As such, a testing program was undertaken to investigate the structural properties of some of these materials. A series of compressed earth blocks made from a mixture of earth and cement compressed to 8 - 12 MPa were tested for their compressive capacity in masonry prisms. The blocks had been weathered for one to two years. The blocks with no cement had a capacity of 2.22 MPa, while cement stabilized blocks had a capacity of 8.11 MPa. Weathering did not result in any significant reduction in the strength of the blocks. Bales of high density straw were tested both with and without cement plaster skins. Unplastered bales exhibited a stiffness between 0.3 - 0.7 MPa when oriented Flat, and 1.2 MPa on edge. The bales had a dilation ratio between 0.1 - 0.3 in the Flat orientation and averaging 3.5 in the Edge orientation. The high density bales plastered with cement plaster exhibited ultimate strengths averaging 171.2 kN/m. Capacity was heavily dependent on plaster strengths, and when normalized for plaster strengths, high density bales had capacities lower than those of regular density bales tested previously (34.1 kN/m/MPa compared to 44.3 kN/m/MPa). Three walls made of straw with cement plaster were constructed with pin-ended conditions to study the effects of buckling in straw bale walls. The average capacity was 12.8 kN/m/MPa when normalized for plaster strength. Pin ends resulted in plastic hinges forming more easily in the walls, and pin ended specimens had a 75% reduction in strength compared to previous tests of "standard" end conditions. Taller walls also resulted in reduced strengths. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-10-30 09:26:46.491
244

Šiaudų briketais kūrenamo katilo energetinių parametrų tyrimas / Research on energetic parameter of straw briquette fired boiler

Norkutė, Dovilė 02 June 2011 (has links)
Šiaudų briketais kūrenamo katilo energetiniai parametrai išnagrinėti magistrantūros baigiamajame darbe. Aptartas šiaudų, kaip kuro potencialas Lietuvoje, jų ištekliai bei panaudojimo galimybės kurui. Apžvelgtas šiaudų ruošimas kūrenimui, šiaudų kūrenimo būdai, įrenginiai, kurie gamina briketus, bei katilai kūrenami šiaudų briketais. Darbe yra pateikta šiaudų kuro sudėtis, kenksmingų medžiagų kiekiai, briketų energetinis efektyvumas ir ekonominė reikšmė. Tyrimo tikslas yra apskaičiuoti degimo proceso šiluminę galią, nustatyti katilo šiluminę galią, apskaičiuoti katilo efektyvumą esant skirtingai šiaudų briketų drėgmei bei masei. Į aplinką išmetamų kenksmingų emisijų nustatymas. Teoriškai ir eksperimentiškai ištyrus 10 kW galios katilą nustatyta, kad didžiausia katilo galia Pk prie 12 % šiaudų briketų drėgnio yra 23,17 kW, esant 14 % drėgniui, didžiausia katilo galia yra 15,99 kW, o esant 16 % drėgniui – 11,48 kW. Esant maksimaliam katilo efektyvumui, kai ηvid =77,2 %, katilo galia Pk yra 23,17 kW, o degimo proceso Pd galia padidėja iki 29,03 kW. Kai katilo naudingumo koeficientas yra maksimalus (ηvid =77,2 %), tada kuro sąnaudos siekia7 kg/h.Darbe pateikti šiaudų briketų deginimo tyrimų rezultatai. Tyrimų metu gauti ir apskaičiuoti rezultatai pateikti lentelėse, bei pavaizduoti grafiškai. / In the master’s thesis energetic parameters of the boiler heated by straw briquettes were analyzed. The potential of straw as a fuel in Lithuania, its resources and usage for fuel were discussed. The review of preparation of straw for heating, ways of heating with straw, equipment that makes briquettes and boilers heated by straw briquettes was performed. The paper presents the composition of straw fuel, the amounts of harmful materials, energetic efficiency of briquettes and economic significance. The aim of the research is to calculate the thermal power of the burning process, to define the thermal power of the boiler, to calculate the efficiency of the boiler at different humidity and mass of straw briquettes, to define the harmful emissions that affect the environment. Having analyzed theoretically and experimentally the boiler of 10 kW power, it was defined that the highest power Pk achieved at 12 % straw briquette humidity is 23,17 kW, when the humidity is 14 % , the highest power of the boiler is 15,99 kW, whereas at the 16 % humidity it is 11,48 kW. At the maximum power of the boiler, when ηvid =77,2 %, the power of the boiler Pk is 23,17 kW, the power of the burning process Pd reaches 29,03 kW. When the efficiency coefficient of the boiler is ultimate (ηvid = 55,3 %), the input of fuel reaches 7 kg/h. The paper presents the results of the research on burning straw briquettes. According to the results, different parameters mentioned in the research aims were... [to full text]
245

Enhancing the methane production from untreated rice straw using an anaerobic co-digestion approach with piggery wastewater and pulp and paper mill sludge to optimize energy conversion in farm-scale biogas plants

Mussoline, Wendy 12 December 2013 (has links) (PDF)
The research describes an optimized waste-to-energy technology that utilizes agricultural residues for renewable energy, while reducing global methane emissions and maintaining food security. Laboratory-, pilot- and farm-scale anaerobic batch digesters were evaluated to enhance methane production from the anaerobic digestion of untreated rice straw in dry conditions using a novel co-digestion approach. An existing farm-scale biogas plant loaded with rice straw and piggery wastewater produced 295 MWh in a 422-day digestion cycle. The long acclimation period (approximately 200 days) and low biogas yield (181 LCH4/kgVS) could be enhanced by adding anaerobic sludge from the pulp and paper mill treatment process. In a laboratory setting, the addition of the sludge resulted in a specific methane yield of 335 LCH4/kgVS within 92 days. Hydrolysis of the straw was accelerated, and stable conditions were observed in terms of pH, alkalinity and nutrients. Similar improvements were demonstrated in pilot-scale digesters (1 m3) - a specific methane yield of 231 LCH4/kgVS was achieved in a 93-day digestion cycle with the sludge compared to 189 days without the sludge. Insufficient mixing within the pilot-scale system caused lower overall methane yields than those obtained in the laboratory-scale digesters. If sufficient mixing and mesophilic conditions are maintained within the farm-scale system, the co-digestion of rice straw with pig wastewater and paper mill sludge (wet weight ratio of 1:1.25:0.5) has the potential to reduce the retention time to three months (versus 422 days) and increase methane yields to over 300 LCH4/kgVS
246

De l'extraction de la lignine à sa valorisation / From lignin extraction to its valorization

Constant, Sandra 27 September 2012 (has links)
L'objectif de ce travail de thèse vise à étudier la conversion de la lignine dans des conditions oxydantes hydrothermales, par catalyse hétérogène. La lignine est l'une des principales constituantes des matériaux ligno-cellulosiques. Considérée comme déchet des procédés de valorisation de la cellulose, elle est majoritairement brûlée pour produire de l'énergie. De par sa structure de polymère phénolique, la lignine peut être considérée comme la principale source de noyaux aromatiques. Une méthodologie analytique complexe a, dans un premier temps, été mise en place pour permettre une caractérisation poussée des lignines et produits d'oxydation. Les lignines étudiées ont été extraites à partir de la paille par un procédé organosolv. Le procédé d'extraction influe sur les rendements mais aussi sur les structures et propriétés des différents produits. Les catalyseurs d'oxydation sont des oxydes divisés des métaux de transition, synthétisés par voie alginate. L'oxydation de la vanilline, composé modèle de la lignine, met en évidence des phénomènes d'oligomérisation des produits formés. Lors de l'oxydation des lignines, l'utilisation d'un catalyseur augmente les rendements et modifie les équilibres de dépolymérisation – oligomérisation. / The objective of this thesis is to study the conversion of lignin in oxidizing hydrothermal conditions, by heterogeneous catalysis. Lignin is among the main constituents of lignocellulose materials. Being considered like a waste of the cellulose valorization procedures, it is mostly burned to produce the energy. Taking into account its phenolic polymer structure, lignin can be considered as the main source of aromatic rings. Complex analytical methodology has initially been set up to allow a thorough characterization of lignins and oxidation products. Lignins were extracted from the straw by the organosolv procedure. The extraction process affects not only yields but also the structures and properties of products. The oxidation catalysts are transition metal oxides, synthesized by an alginate route. The oxidation of vanillin (lignin's model compound) shows the oligomerization phenomena of obtained products. In the oxidation of lignin, the use of a catalyst increases the yield and modifies the equilibrium of depolymerization - oligomerization.
247

Litter accumulation in Pinus patula plantations and the role of ectomycorrhizal fungi in a forest ecosystem

Dames, Joanna Felicity January 1996 (has links)
A thesis submitted in the Faculty of Science, University of Witwatersrand, Johannesburg for the degree of Doctor of Philosophy. Johannesburg, 1996. / Litter accumulates on the forest floor in Pinus patula plantations in Mpumalanga, South Africa and as a result nutrients become immobilized and site productivity is reduced. Studies have correlated litteraccumulation with abiotic factors, such as high altitude sites, high rainfall soils derived from the timeball series (shale) have thick litter layers. This study focuses on the biotic factors involved in litter accumulation. [Abbreviated Abstract. Open document to view full version] / GR 2017
248

Production of bioethanol from wheat straw hydrolysate using reverse membrane bioreactor (rMBR) / Bioetanol produktion från vetehalm hydrolysat med användning av omvänd membranbioreaktor

Khin San, Jessica January 2018 (has links)
The second-generation bioethanol production in which lignocellulosic material is used as feedstock faces some difficulties. Lignocellulosic materials have to be pretreated prior to fermentation. In the pretreatment stages several inhibitory compounds, which can negatively affect the metabolic and physiologic activity of the microorganism used, Saccharomyces cerevisiae, are released. Moreover, wild strains of Saccharomyces cerevisiae cannot co-utilize the hexose and pentose saccharides present in the lignocellulosic substrate. In this study, reverse membrane bioreactor (rMBR) was applied to address the difficulties faced in the secondgeneration ethanol production. Semi-synthetic medium and pretreated wheat straw slurry containing different level of glucose, xylose and inhibitor concentrations were fermented in rMBR using genetically-modified xylose-consuming S. cerevisiae. The diffusion rate of different substrates and metabolites during fermentation were measured and analyzed. The results showed that the application of rMBR facilitated simultaneous utilization of hexose and pentose sugars and enhanced the cell tolerance of the inhibitor present in the medium.
249

Decomposition dynamics of sugarcane straw in the central-southern Brazil / Dinâmica da decomposição da palha de cana-de-açúcar na região centro-sul do Brasil

Pimentel, Laisa Gouveia 29 September 2017 (has links)
The adoption of mechanical unburned sugarcane harvesting increases the quantity of straw left on the soil. This material has a high potential for 2G ethanol and bioelectricity production. Although the straw maintenance has an essential role in the soil properties and crop performance. The straw decomposition is a key process to investigate and to inform the correct removal management decisions. Diverse factors affect the decomposition rate, such as: quality and quantity of straw; edaphoclimatic conditions; and management practices. Therefore, we conducted a field study at two sites within central-southern Brazil, the largest sugarcane-producing region in the world, encompassing two harvesting seasons (rainy and dry) over two years to evaluate the sugarcane straw decomposition dynamics under different removal rates. The main hypothesis is that the high removal unbalances the soil environment and reduce de C supply for the microorganisms, decreasing the microbial activity and consequently the straw decomposition rate. The straw removal management affected the decomposition rate, which the lowest decomposition was associated with high removal. The C and N loss was two- and threefold greater in the second year than in the first year of experimentation, respectively. Overall, the straw cellulose decreased by 13%, the hemicellulose 7%, and the lignin proportionally enriched by 92% after two years. Throughout the decomposition process, the straw chemical changes were detected using the traditional method, wet chemical extractions, and using the spectroscopy technique, Diffuse Reflectance Infrared Fourier Transform DRIFT. In this sense, in order to trace straw cellulose and hemicellulose changes we suggested the use of 896, 987, 1173, and 1447 cm-1 peaks, whereas to trace lignin changes, the absorbance at 1510 cm-1 seems to be an efficient predictor. The soil bacterial community was most affected by the time of decomposition. The straw quality explained 23.2% of the total bacterial variation, in which hemicellulose accounting for 17.2% of this variation. Moreover, the bacterial structure was subtle affected by the sugarcane straw removal. Overall, our study showed that the straw removal for 2G ethanol and bioelectricity production affect the straw decomposition dynamics in commercial sugarcane areas in Brazil. The time was the main regulator of changes in straw chemical contents and in the soil bacterial structure. The use of crop residues for energy purposes is one of the principal alternatives to increase bioenergy production in the next few years. However, the sugarcane straw removal should be done with prudence, since the straw removal rate affected the straw decomposition dynamics and consequently it should affect the nutrient recycling and C cycle. / A adoção da colheita mecanizada sem queima prévia da cana-de-açúcar aumenta a quantidade de palha sobre o solo. Essa palha tem um alto potencial para produção de etanol 2G e bioeletricidade. No entanto, a manutenção da palha tem papel essencial nas propriedades do solo e no desempenho das culturas. A decomposição da palha é um processo chave para investigar e informar sobre corretas decisões acerca do manejo da remoção. Diversos fatores afetam a taxa de decomposição, tais como: qualidade e quantidade da palha; condições edafoclimáticas; e práticas de manejo. Portanto, realizamos um estudo de campo em dois locais no centro-sul do Brasil, maior região produtora de cana-de-açúcar no mundo, abrangendo duas épocas de colheita (chuvosa e seca) ao longo de dois anos para avaliar a dinâmica de decomposição da palha da cana-de-açúcar sob diferentes taxas de remoção. A principal hipótese é de que a alta remoção de palha desequilibre o ambiente edáfico e reduza o fornecimento de C para os microrganismos, diminuindo a atividade microbiana e consequentemente a taxa de decomposição da palha. O manejo de remoção afetou a taxa de decomposição da palha, a menor taxa de decomposição foi associada a maiores remoções. A perda de C e N foi duas e três vezes maior no segundo ano do que no primeiro ano de condução do experimento, respectivamente. Em geral, a celulose da palha diminuiu em 13%, a hemicelulose em 7% e a lignina proporcionalmente enriqueceu em 92% após dois anos. Mundancas na composição química da palha ao longo do processo de decomposição foram detectadas tanto utilizando o método tradicional, via extrações químicas sequenciais, quanto atravéz de técnica espectroscópica, como o Diffuse Reflectance Infrared Fourier Transform DRIFT. Assim, para verificar alterações da celulose e da hemicelulose da palha suger-se o uso das picos espectrais de 896, 987, 1173 e 1447 cm-1, enquanto que para verificar mudanças na lignina os valores de 1510 cm-1 mostrou-se um eficiente preditor. A comunidade bacteriana do solo foi afetada pelo tempo de decomposição. A qualidade da palha explicou 23,2% da variação bacteriana total, onde a hemicelulose representou 17,2% dessa variação. Além disso, a estrutura bacteriana foi sutilmente afetada pelo manejo de remoção da palha da cana-de-açúcar. No geral, nosso estudo mostrou que a remoção de palha para a produção de etanol 2G e bioeletricidade afetará a dinâmica da decomposição da palha nas áreas comerciais de cana-de-açúcar do Brasil. O tempo foi o principal regulador das mudanças nos conteúdos bioquímicos da palha e na estrutura bacteriana do solo. O uso de resíduos de culturas para fins energéticos é uma das principais alternativas para aumentar a produção de bioenergia nos próximos anos. No entanto, a remoção da palha de cana-de-açúcar deve ser feita com prudência, uma vez que a taxa de remoção afetou a dinâmica da decomposição e conseqüentemente deverá afetar a ciclagem de nutrientes e o ciclo do C.
250

Etanol celulósico a partir da palha e do bagaço de cana-de-açúcar: pré-tratamentos e conversão biotecnológica não convencionais / Cellulosic ethanol from sugarcane straw and bagasse: non-conventional pretreatments and biotechnological conversion

Mori, Naila Ribeiro 15 October 2015 (has links)
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.

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