Made available in DSpace on 2017-05-12T14:46:46Z (GMT). No. of bitstreams: 1 Cristiane.pdf: 1676874 bytes, checksum: b32327481322325a528776559d52d690 (MD5) Previous issue date: 2012-12-12 / Attempting to associate waste treatment to the production of clean and renewable energy, the present research aimed to evaluate the biological production of hydrogen using wastewater from the manioc starch treatment industry, a liquid wastewater of high organic content, generated during the processes of extraction and purification of manioc starch. The experiment was carried out in two upflow fixed-bed anaerobic reactors. As support, bamboo stems and low density polyethylene scraps. Made with pexiglass, each reactor was built with 75 cm of height, with 2.96 L of useful volume for the reactor with bamboo support and 3.13 L for the one with Polyethylene support. The inoculum, collected in a pilot anaerobic reactor, received thermal pretreatment and was recirculated in the reactors for 48 h. Then, alimentation was initiated in a continuum manner. The system was operated with hydraulic detention time (TDH) of 4 and 3 h, at 36 °C and initial pH of 6.0. In the TDH of 4 h, 3 organic loading rates were applied (COV), of 28; 15 and 26 g.L-1.d-1; in the TDH of 3 h 4 COV were applied, of 35; 22; 22 and 27 g.L-1.d-1. The application of the COV did not follow any particular pattern due to the variability of the wastewater constitution. Hence, the effects of TDH, COV and the support mean on the production of hydrogen were evaluated, as well as the influence of bamboo and of low density polyethylene in the fixation and selection of microorganisms that produce hydrogen. Maximum hydrogen production in the reactor using bamboo was of 2.9 L.d-1 in TDH 4h and of 2.2 L.d-1 in the reactor using polyethylene in TDH of 3 h. Hydrogen percentage of 25% in biogas was reached in the reactor using bamboo and of 29% in the reactor using polyethylene. The yielding obtained was of 0.6 L H2.g-1sugar in the reactor using bamboo in TDH 4 h and of 0.8 L H2.g-1sugar in the reactor using polyethylene in TDH 3 h. In both reactors, the mean total sugar removal was of approximately 90%. / Buscando aliar o tratamento de resíduos à produção de energia limpa e renovável, o presente trabalho teve como objetivo avaliar a produção biológica de hidrogênio a partir da água residuária da indústria de fécula de mandioca, resíduo líquido de elevada carga orgânica, gerado durante os processos de extração e purificação do amido. O experimento foi realizado em dois reatores anaeróbios de leito fixo e fluxo ascendente. Como meio suporte foram utilizadas hastes de bambu e aparas de polietileno de baixa densidade. Confeccionados em pexiglass, cada reator foi construído com 75 cm de altura, o volume útil calculado foi de 2,96 L para o reator com suporte de bambu e 3,13 L para o reator com suporte de polietileno. O inóculo, coletado em um reator anaeróbio piloto, recebeu pré-tratamento térmico e foi recirculado nos reatores por 48 h. Em seguida, iniciou-se a alimentação em modo contínuo. O sistema foi operado com tempo de detenção hidráulica (TDH) de 4 e 3 h, a 36 °C e pH inicial 6,0. No TDH de 4 h foram aplicadas 3 cargas orgânicas volumétricas (COV) de 28; 15 e 26 g.L-1.d-1; no TDH de 3 h foram aplicadas 4 COV de 35; 22; 22 e 27 g.L-1.d-1. A aplicação das COV não seguiu a um padrão devido à variabilidade na constituição da água residuária. Dessa forma, foram avaliados os efeitos do TDH, da COV e do suporte sobre a produção fermentativa de hidrogênio e também a influência do bambu e do polietileno de baixa densidade na fixação e seleção dos micro-organismos produtores de hidrogênio. A produção máxima de hidrogênio no reator com bambu foi de 2,9 L.d-1 em TDH 4 h e de 2,2 L.d-1 no reator com polietileno em TDH de 3 h. Foram alcançados percentuais de hidrogênio no biogás de 25% no reator com bambu e 29% o reator com polietileno. O rendimento obtido foi de 0,6 L H2.g-1açúcar no reator com bambu em TDH 4 h e 0,8 L H2.g-1açúcar no reator com polietileno em TDH 3 h. Em ambos os reatores a degradação média de açúcares totais foi de aproximadamente 90%.

<p>Cilj doktorske disertacije je da poveže teorijska znanja iz oblasti<br />matematičkog modelovanja sa eksperimentalnim ispitivanjem<br />sagorevanja pšenične slame u nepokretnom sloju, u cilju formiranja<br />matematičkog modela koji će kroz računarske simulacije omogućiti<br />analizu uticaja radnih parametara (gustine sloja, količine vazduha za<br />sagorevanje) na odvijanje procesa sagorevanja, odnosno određivanje<br />brzine sagorevanja, temperaturskog profila u sloju i koncentracije<br />pojedinih gasova u sloju.<br />Takođe, kroz eksperimentalna merenja, osim validacije modela,<br />urađena je analiza i opisivanje pojava i fenomena koji se odvijaju pri<br />sagorevanju pšenične slame u nepokretnom sloju.</p> / <p>The goal of doctoral dissertation is to bring together theoretical knowledge in<br />the field of mathematical modelling and experimental investigation of wheat<br />straw combustion in fixed bed, with the aim of developing a mathematical<br />model which will, through computer simulation, enable the analysis of effects<br />of operational parameters (bed density, amount of combustion air) on the<br />combustion process, as well as the determination of burning rate, bed<br />temperature profile and concentration of certain gases in the bed.<br />Also, through experimental measurements, in addition to validating the<br />mathematical model, the analysis and description of the phenomena that<br />occurre during the combustion of wheat straw in a fixed bed, was performed.</p>

The Insect Cell - Baculovirus Expression Vector System (IC-BEVS) is widely used for the production of complex recombinant (glyco)proteins. The simplicity of insect cell cultivation in suspension serum-free media and the easy construction of recombinant baculovirus vectors have made the BEVS quite an effective expression system. On the other hand, the BEVS is a transient lytic system that may present some drawbacks in purification and potential degradation of the products. Among the various insect cell lines, the High-Five cell line has a great potential for the production of recombinant proteins using the BEVS in stirred bioreactors, reaching high cell densities and high protein production levels. Moreover, these cells can tolerate environmental stresses and can be cultivated on a large scale (Chapter 1). Unfortunately, up to now, there have been limited data available regarding suitable culture conditions and the metabolism of High-Five cells, a key requirement for the rational development of new processes. The overall goal of the present work was the study of these High-Five cells, in order to develop sophisticated new processes as alternatives to batch cultivation. The original contributions have been developed along two axes. The first axis concerns the study of the physiology and metabolism of High-Five cells. At first, we undertook a study aiming to prevent cell ring formation on suspension culture recipient walls (Chapter 2). Next, we analyzed environmental factors affecting insect cell growth and death, by comparing and developing methods able to distinguish between apoptosis and necrosis of cells (Chapter 3). The comprehensive study of the extended metabolism of High-Five cells was done using a metabolic flux network that takes account of the catabolism but also the anabolism of uninfected and baculovirus-infected cells (Chapter 4). The second axis was the application of the previously gained knowledge on High-Five cells to develop high-density systems specifically adapted to them: a fed-batch feeding strategy consisting of different pulses developed to increase the productivity of cells during infection (Chapter 5) and a fixed-bed reactor system (Chapter 6), as an alternative to classic perfusion, adapted to High-Five cells for recombinant protein production. In sum, new physiological and metabolic knowledge has been translated into new process options for High-Five cells.

M. Tech. Engineering: Chemical / Researches the usability and efficiency of the synthesized PPy/Al2O3 nanocomposite as adsorbent in Cr(VI) remediation from contaminated wastewaters.The specific objectives of the study are:to synthesise and characterize the PPy/Al2O3 nanocomposite ; to characterize the prepared nanocomposite using several sophisticated instruments such as, SEM, BET, XRD, et cetera ; to carryout batch adsorption equilibrium and kinetics studies for evaluating the performance of the nanosorbent and to gain insight into the underlying adsorption mechanisms.; to apply adsorption equilibrium and kinetic models.; to assess the breakthrough performance of the PPy/Al2O3 nanocomposite for Cr(VI) adsorption by varying operating parameters, in fixed bed column mode and to apply existing mathematical models to predict the performance of fixed bed adsorption systems and to obtain column design parameters.

There is a consensus worldwide that the share of renewable energy sources should be increased to mitigate climate change. The strive to increase the renewable energy fraction can partly be met by an increased utilization of different biomass feedstocks. Many of the "new" feedstocks puts stress on certain challenges such as air pollution emissions and operation stability of the combustion process. The overall objective was to investigate, evaluate, and explain the effects of fuel design and combustion control - fuel engineering - as primary measures for control of slag formation, deposit formation, and fine particle emissions during biomass combustion in small and medium scale fixed-bed appliances. The work in this thesis can be outlined as having two main focus areas, one more applied regarding fuel engineering measures and one more fundamental regarding the time-resolved release of ash forming elements, with particular focus on potassium. The overall conclusion related to the abatement of particle emissions and slag formation, is that the release of fine particle and deposit forming matter can be controlled simultaneously as the slag formation during fixed-bed biomass combustion. The methodology is in this perspective denoted “fuel engineering” and is based on a combined approach including both fuel design and process control measures. The studies on time-resolved potassium release showed that a Macro-TG reactor with single pellet experiments was a valuable tool for studying ash transformation along the fuel conversion. The combination of dedicated release determinations based on accurate mass balance considerations and ICP analysis, with phase composition characterization by XRD, is important for the understanding of potassium release in general and time-resolved data in particular. For wood, the results presented in this work supports the potassium release mechanism from "char-K" but questions the previously suggested release mechanism from decomposition of K-carbonates. For straw, the present data support the idea that the major part of the potassium release is attributed to volatilization of KCl. To further explore the detailed mechanisms, the novel approach developed and applied in this work should be complemented with other experimental and analytical techniques. The research in this thesis has explored some of the challenges related to the combined phenomena of fuel conversion and ash transformation during thermochemical conversion of biomass, and has contributed with novel methods and approaches that have gained new knowledge to be used for the development of more effective bioenergy systems.

La gazéification étagée est une technologie innovante pour la production d’énergie renouvelable de petite et moyenne puissances, pour laquelle l'élargissement de la gamme de biomasses utilisables constitue un enjeu majeur de développement. Cette thèse porte spécifiquement sur la pyrolyse oxydante en lit fixe, première étape clé du procédé, qui conditionne fortement la performance et la fiabilité de cette technologie. Trois types de biomasses – pin, miscanthus, et paille – conditionnées sous forme de granulés ont été étudiés. Une étude expérimentale a été réalisée sur un réacteur pilote à lit fixe de 20 cm de diamètre et 1.6 m de hauteur permettant de reproduire des conditions opératoires proches de celles rencontrées durant l'étape de pyrolyse dans les gazéifieurs industriels. Le fonctionnement du procédé pour les trois biomasses a été caractérisé par la mesure du ratio air/biomasse, des températures, des rendements en charbon, gaz permanents et condensables et de leurs compositions. Une attention particulière a été portée à la zone d'oxydation qui se propage verticalement vers le haut dans le lit de biomasse. Une méthodologie a été développée pour mesurer la vitesse de propagation, l'épaisseur et le tassement de cette zone et étudier l'impact de la nature de la biomasse. Dans un lit de granulés de bois, la vitesse et l'épaisseur de la zone d'oxydation est 25 % plus faible que dans un lit de granulés de paille ou miscanthus. L'effet catalytique des matières minérales sur les réactions de pyrolyse primaire et secondaire et son impact sur le fonctionnement du procédé, ont également été mis en évidence. / Staged gasification is an innovative technology for small and medium renewable energy production. The expansion of the range of usable biomass remains a major obstacle to development. This thesis focuses specifically on the oxidative pyrolysis in a fixed bed, the first step of the process that strongly influences the performance and reliability of this technology. Three types of biomass- pine, miscanthus and wheat straw - in form of pellets were studied. An experimental study was carried out in a pilot fixed bed reactor of 20 cm diameter and 1.6 m height allowing the reproduction of similar conditions to those existing in the pyrolysis step of an industrial gasifier. The process operation for the three biomasses was characterized by measuring the air/biomass ratio, bed temperature, yields and compositions of char, permanent gases and condensates. A particular attention was paid on the oxidation zone which propagates upward towards the raw biomass. A method was developed to measure the propagation velocity, thickness and the compaction of the oxidation zone and to study the impact of the biomass nature. Velocity and thickness of this zone were 25 % lower in a fixed bed of wood pellets than in beds of wheat straw or miscanthus. Catalytic effect of the mineral matters on primary and secondary pyrolysis reactions and their impact on the process operation have been highlighted.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-09-14T12:22:51Z No. of bitstreams: 1 JOSÉ RILDO DE OLIVEIRA - TESE (PPGEP) 2006.pdf: 1131201 bytes, checksum: ba0909f714e2920247098ffc14790d7d (MD5) / Made available in DSpace on 2018-09-14T12:22:51Z (GMT). No. of bitstreams: 1 JOSÉ RILDO DE OLIVEIRA - TESE (PPGEP) 2006.pdf: 1131201 bytes, checksum: ba0909f714e2920247098ffc14790d7d (MD5) Previous issue date: 2006 / Estudou-se o comportamento das propriedades físicas do feijão-macáçar ( Vigna unguiculata (l.) Walpers) - porosidade, área superficial, área específica, calor específico, massa especifica aparente e isotermas de equilíbrio -, com teor de água inicial de 20, 40 e 65 %, base úmida, os efeitos do teor de água inicial do produto, da temperatura e da velocidade do ar de secagem, sobre a cinética de secagem do produto. As isotermas de equilíbrio do feijão-macáçar com teor de água inicial de 65%, base úmida, foram determinadas pelo método estático, a temperaturas de 20, 30, 40 e 50 ºC, com umidade relativas variando de 0,10 a 0,85, decimal. Para análise dos dados experimentais, foram utilizados cinco modelos matemáticos: Henderson-Thompson; modelo de Henderson-Thompson modificado por Cavalcanti Mata; modelo de Chung- Pfost; modelo de Oswin modificado; modelo de Halsey modificado. O estudo da cinética de secagem em camada fina foi feito com temperaturas de 40, 55 e 70 ºC, velocidade do ar de secagem de 0,2, 0,5 e 0,8 m/s. Foi ajustado o modelo de Page aos dados experimentais para obter a curva de secagem. Para realizar a parte experimental da secagem foi projetado e construído um secador em escala laboratorial para secagem em camada espessa e em camada fina, simultaneamente, com capacidade para secar oito quilos de grão em camada espessa e um quilo em camada fina. A secagem em camada espessa do produto foi feita a temperaturas de 50, 60 e 70 ºC, em camada com espessura de 60 cm e vazão do ar de secagem de 0,59 m3/min. Utilizou-se o modelo proposto por BAKKER-ARKEMA et al. (1974) - Modelo da Universidade Estadual de Michigan (M.S.U.) – e o modelo de Thompson para simular o processo de secagem. A discretização das equações diferenciais foi feita pelo método dos volumes finitos, utilizando-se uma formulação explícita e a função de interpolação espacial “upwind”. / The behavior of cowpea been’s physical properties was studied (Vigna unguiculata (l.) Walpers) - porosity, surface area, specific area, specific heat, bulk density and the relative equilibrium humidity, - with initial moisture content range 20, 40 and 65 %, wet basis, the initial moisture effects content the product, the temperature and the air drying speed , on kinetic of product drying. The relative equilibrium humidity of cowpea been with initial moisture content range 65 %, wet basis, had been determined by the static method, for temperatures of 20, 30, 40 and 50 ºC, with relative humidity varying between 0,10 and 0,85, decimal. For experimental data’s analysis, five mathematical models had been used: Henderson-Thompson’s; Henderson- Thompson’s model modified by Cavalcanti Mata; Chung-Pfost’s model; Oswin’s modified model; Halsey’s modified model. The study of the drying kinetic in thin-layer was made with temperatures of 40, 55 and 70 ºC, air drying speed of 0,2, 0,5 and 0,8 m/s. The Page’s model was adjusted to the experimental data to get the drying curve. To carry through the drying experimental part was projected and buidet a drier in laboratorial scale for fixed-bed drying and thin-layer , simultaneously, with capacity to dry eight kilos of grain in thick layer and one kilo in fine layer. The fixed-bed drying of the product was made with temperatures of 50, 60 and 70 ºC, in layer with thickness of 60 cm and air outflow of 0,59 drying of m3/min. The considered BAKKERARKEMA’s et al (1974) model was used. - Model of the Michigan State University (M.S.U.) - and Thompson’s model to simulate the drying process. Discretization of the differential equations was made by the finite volumes method, using an explicit formularization and the function of upwind space interpolation.

Made available in DSpace on 2014-06-11T19:24:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-23Bitstream added on 2014-06-13T20:32:10Z : No. of bitstreams: 1 zanelato_ai_me_sjrp.pdf: 1477010 bytes, checksum: e2437c2c0ba00be5a6b7df73d8be90f5 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho teve como objetivo produzir enzimas celulolíticas por fermentação em estado sólido (FES), em um bioreator de leito fixo, empregando-se o fungo termofílico Myceliophthora sp. e utilizando-se como substratos bagaço de cana-de-açúcar e farelo de trigo. Os testes foram realizados inicialmente em sacos de polipropileno apresentando uma boa produção de CMCase (550U/g) no período de 96 horas de fermentação. As variáveis controladas foram a temperatura de fermentação (40, 45 e 50ºC), umidade inicial (75, 80 e 85% b.u.) e proporção do substrato de bagaço de cana e farelo de trigo (1:1, 3:7 e 1:9 peso). Os estimadores estatísticos não indicaram diferença significativa da produção de celulase com as variações da proporção de bagaço de cana e de farelo de trigo, com a temperatura e com a umidade inicial do substrato, contudo, os melhores resultados foram obtidos para a proporção de 70% de bagaço de cana e 30% de farelo de trigo, temperatura de 50oC e umidade inicial do substrato de 80%. Nos testes em escala de bioreator, foi empregado um leito fixo de 7cm de diâmetro e 50cm de comprimento, encamisado, operado nas condições experimentais de melhor resultados obtidos na escala de sacos, sendo a temperatura da camisa e vazão de ar as variáveis de interesse. O fungo apresentou um bom desenvolvimento no reator, tendo uma produtividade enzimática semelhante à encontrada em escala de saco. Foi observado um gradiente de umidade no interior do leito, sendo este crescente do fundo para o topo do bioreator, comportamento inverso ao da atividade enzimática. As vazões variaram entre 80 e 120 L/h e não afetaram estatisticamente a fermentação, possuindo pouca influência sobre as distribuições longitudinais de umidade e de atividade enzimática. Já os ensaios para as temperaturas de 45 e 50oC mostraram-se distintos, sendo a maior produção de enzimas após 96h... / This work aimed to produce celullolytic enzymes through solid state fermentation in a fixed bed bioreactor, using the fungus Myceliophtora sp. and wheat bran and sugar cane bagasse as substrate. Initial tests were performed in polypropylene plastic bags, and satisfactory production of CMCase (550U/g.d.s.) was observed at 96h of fermentation. The controlled variables were the temperature (40, 45, and 50o C), the initial moisture content (75, 80, and 85%, w.b.), and wheat bran to sugar cane bagasse proportion (1:1, 3:7, and 1:9, weight). The experimental results did not differ statistically for any experimental condition adopted, even though the best results were obtained using the proportion 3:7 wheat bran/sugar cane bagasse 3:7, 50o C temperature, and 80% initial moisture content. A jacketed fixed bed bioreactor 7.62cm ID and 50cm long was used for scaling-up, and temperature, solid initial moisture content, and air flow rate were used as variables. The fungus adapted well to the bioreactor and to the experimental conditions, and the production of enzymes was similar to the tests performed in the plastic bags. It was observed a longitudinal gradient of moisture, increasing from the bottom to the top of the reactor, opposite effect observed for the enzyme production. The air flow rate was varied from 80 to 120L/h and did not affect neither the moisture nor the enzyme distributions. However, the experiments carried out at 45 and 50o C were statistically distinct, and the enzyme production at 50o C at 96h was larger than at 45o C. At 144h of fermentation, the results at 45o C were similar to those observed at 50o C and 96h. It was observed temperature peaks, the higher one at 18h of fermentation, which was 6o C above the temperature fixed through the jacket and the air at the entrance, for 45o C temperature and 80L/h air flow rate

Submitted by FÁBIO ROBERTO VIEIRA (fabiorobertovieira@bol.com.br) on 2018-04-18T19:02:13Z No. of bitstreams: 1 Fabio Roberto Vieira - Dissertação versão final.pdf: 2356751 bytes, checksum: 1c49b0709cb5e5a4d26bcf03bbbd3670 (MD5) / Approved for entry into archive by Pamella Benevides Gonçalves null (pamella@feg.unesp.br) on 2018-04-19T19:12:40Z (GMT) No. of bitstreams: 1 vieira_fr_me_guara.pdf: 2356751 bytes, checksum: 1c49b0709cb5e5a4d26bcf03bbbd3670 (MD5) / Made available in DSpace on 2018-04-19T19:12:40Z (GMT). No. of bitstreams: 1 vieira_fr_me_guara.pdf: 2356751 bytes, checksum: 1c49b0709cb5e5a4d26bcf03bbbd3670 (MD5) Previous issue date: 2018-02-20 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Nessa dissertação é investigada o aproveitamento energético da casca de arroz pela aplicação do processo de pirólise lenta em um reator de leito fixo, o qual foi projetado e construído para realização de trabalho. É estudada a influência dos parâmetros do processo nas características do biochar obtido a partir da casca de arroz, com o objetivo avaliar a sua potencialidade na geração de energia. Para tal foi realizada caracterizações físico-química da casca de arroz in natura e do biochar obtido, aplicando-se diversas técnicas de análise, além da avaliação da eficiência energética. As análises foram estudadas a fim de determinar as condições experimentais que favorecem as características do biochar, tais como poder calorífico superior (PCS) e concentração de carbono fixo, e também o rendimento na produção do mesmo. Foi utilizado um planejamento experimental, conforme metodologia de Taguchi, utilizando-se uma matriz L9 e variando-se os parâmetros que influenciam na pirólise, sendo eles a taxa de aquecimento (β) 5, 10 e 20 ºC/min, temperatura (T) de 300, 400 e 500 ºC, tempo de residência (t) de 3600, 5400 e 7200 s e massa da biomassa in natura (m) de 125, 250 e 500 g. Os resultados indicaram que para os diferentes parâmetros estudados, o maior rendimento de biochar (37,71%) foi observado na condição experimental realizada no teste 7, sendo adotado β=20 ºC/min, T=300 ºC, t=5400 s, e m=500 g. O teste 6 apresentou o maior PCS, 49,05% maior que o da casca de arroz in natura, sendo adotado β=10 ºC/min, T=500 ºC, t=5400 s e m=125 g. Na condição de maior concentração de carbono fixo, o teste 3 apresentou melhor resultado (60,10 %), no qual foi adotado β=5 ºC/min, T=500 ºC, t=7200 s e m=500 g. A ANOVA foi aplicada para analisar a variância do processo, sendo que a temperatura foi o parâmetro de maior influência no processo. Também foram determinadas as condições de melhor ajuste para otimização do processo para maior rendimento na produção de biochar (β= 20 ºC/min, T=300 ºC, t=3600 s e m=500 g), para maior concentração de carbono fixo no biochar (β=5 ºC/min, T=500 ºC, t=7200 s e , m=250 g) e para obtenção de biochar com maior PCS (β=10 ºC/min, T=500 ºC, t=3600 s e m=125 g). A avaliação energética mostrou que, tecnicamente, há um ganho energético na aplicação da pirólise lenta da casca de arroz. / In this dissertation is investigated the utilization of the rice husk means slow pyrolysis process in a fixed bed reactor, which was designed and built to perform work. The influence of the process parameters on the characteristics of the biochar obtained from the rice husk is studied, with the objective of evaluating its potential in the energy. For this purpose, physicalchemical characterization of the in natura rice husk and the biochar obtained were performed, applying several analysis techniques, as well as the energy efficiency assessment. The analyzes were studied in order to determine the experimental conditions favoring the biochar characteristics, such as higher heat value (HHV) and fixed carbon concentration, as well as the yield in the production of the same. An experimental design was used, according to Taguchi's methodology, using a L9 matrix and varying the parameters that influence pyrolysis, being the heating rate (β) 5, 10 and 20 ºC / min, temperature (T) of 300, 400 and 500 ° C, residence time (t) of 3600, 5400 and 7200 if mass of the in natura biomass (m) of 125, 250 and 500 g. The results indicated that the highest biochar yield (37.71%) was observed in the experimental condition performed in test 7, using β = 20 ºC / min, T = 300 ºC, t = 5400 s, in = 500 g. Test 6 showed the highest HHV, 49.05% higher than in natura rice husk, being adopted β = 10 ºC / min, T = 500 ºC, t = 5400 s and m = 125 g. In the condition of higher fixed carbon concentration, test 3 presented the best result (60.10%), in which β = 5 ° C / min, T = 500 ° C, t = 7200 s and m = 500 g. ANOVA was applied to analyze the process variance, with temperature being the parameter of greatest influence in the process. It was also determined the conditions of better adjustment for process optimization for higher yield of biochar (β = 20 ºC / min, T = 300 ºC, t = 3600 m = 500 g) for higher fixed carbon concentration in biochar (β = 10 °C/min, T = 500 °C, t = 7200 s, m = 250 g) and to obtain biochar with higher HHV). The energy evaluation showed that, technically, there is an energetic gain in the application of the slow pyrolysis of the rice husk. / 134299/2017-5 / 301819/2015-7

A necessidade de produÃÃo de combustÃveis lÃquidos, principalmente diesel com baixos teores de enxofre para atender recentes legislaÃÃes ambientais, impulsionou a pesquisa sobre a reaÃÃo de sÃntese de Fischer-Tropsch (SFT), que utiliza a polimerizaÃÃo entre monÃxido de carbono (CO) e hidrogÃnio (H2) em diversos tipos de reator e de catalisador. Foram realizadas vÃrias simulaÃÃes da reaÃÃo de sÃntese de Fischer-Tropsch em reator tubular de leito fixo com catalisador de ferro avaliando-se o efeito de determinadas condiÃÃes operacionais na distribuiÃÃo de produtos, de acordo com o modelo desenvolvido para a distribuiÃÃo das massas moleculares dos hidrocarbonetos formados. As condiÃÃes operacionais foram avaliadas de modo favorecer a formaÃÃo de diesel e graxa, que por sua vez podem ser craqueadas visando à produÃÃo de combustÃveis lÃquidos. Um planejamento experimental e uma posterior anÃlise estatÃstica foram executados de forma a apontar as condiÃÃes operacionais que mais influenciam na formaÃÃo de produtos especÃficos como gasolina, diesel e graxas, assim como na conversÃo do gÃs de sÃntese em hidrocarbonetos. Os resultados obtidos mostraram a adequaÃÃo da modelagem adotada com dados experimentais existentes na literatura / In this work, a fixed-bed tubular reactor was modeled and simulated for the Fischer-Tropsch synthesis carried out using iron-based catalysts. The model has considered the fluid-dynamics of the fixed-bed reactor and the polymerization reaction of the Fischer-Trospch synthesis. Several simulations were carried out with the mathematical model to study the effects of the operating conditions on the product distribution and on the yield into hydrocarbons. The simulations were analyzed aiming the optimization of the system toward the production of diesel and wax fractions, which can be later cracked to produce a higher amount of liquid products. The simulations were carried out following a factorial design to identify the operating conditions that most influence the production of each specific product fraction, as gasoline, diesel and waxes, and in the yield of synthesis gas into hydrocarbon