Orientador: Telma Teixeira Franco / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-23T04:10:59Z (GMT). No. of bitstreams: 1 Lacerda_LucyMaraCaciaFerreira_D.pdf: 5787877 bytes, checksum: 81afde238358667a3fdefa912b6c3725 (MD5) Previous issue date: 2013 / Resumo: O uso de microalgas em processos de mitigação ambiental e produção de energia renovável vêm ganhando destaque, mas a otimização das etapas de "upstream" e "downstream" são essenciais para que a viabilidade técnica e econômica seja alcançada e o processo implementado em escala industrial. As condições que maximizam o crescimento celular, a mitigação de CO2, o acúmulo de lipídios e proporcionam um perfil de ácidos graxos, compatível com a produção de biodiesel de elevada qualidade, foram avaliados em função de diferentes temperaturas (18-42 ºC), disponibilidade de carbono na forma de CO2 (ar-40%), disponibilidade de luz (4-192 ?mol.m-2.s-1) e disponibilidade de nitrogênio na forma de NaNO3 (0,25-1,00 g.L-1). A recuperação da biomassa a partir do processo de floculação foi avaliada em função do tipo de floculante (orgânico e inorgânico), dose do floculante (0,005-0,300 g.L-1), pH (4-11) e concentração celular (0,1-1,0 g.L-1). As condições de cultivo selecionadas foram: 108 ?mol.m-2.s-1, 26,5 ºC, 0,25 g.L-1 de NaNO3 e 8,05 % de CO2, sendo obtidos os seguintes resultados: Xmax/X0=14,78 (razão da concentração celular máxima pela concentração inicial); ?max=1,02 d-1 (máxima velocidade específica de crescimento); ?=0,50 d (duração da fase lag); Pmax=0,58 g.L-1.d-1 (produtividade máxima); Pmean=0,31 g.L-1.d-1 (produtividade média); CBmax=1,06 g.L-1.d-1 (Máxima taxa de incorporação de carbono); CBmean=0,55 g.L-1.d-1 (média da taxa de incorporação de carbono); 50% de lipídios e 90% dos FAMES (ésteres metílicos de ácidos graxos) correspondendo aos principais FAMES do biodiesel (C16:0, C18:0, C18:1, C18:2 e C18:3). A predição da qualidade do biodiesel produzido a partir do óleo de microalga forneceu os seguintes resultados: CN=56 (número de cetano), CFPP = 0,8 °C (ponto de entupimento de filtro a frio), ? = 863 kg/m³ (densidade), II = 97 gI2/100g (índice de iodo), ?HC = 39,2 kJ/g (calor de combustão), OSI = 13,8 h (índice de estabilidade oxidativa), e ? = 3,93 mm².s (viscosidade) estando dentro dos valores especificados pelas normas ANP255/2003, EN14213-14214 e ASTM6751. As condições para eficiências de recuperação (RE) da biomassa superiores a 95% foram: intervalos de pH 4,0 a 11,0 (floculante orgânico); 5,0 a 7,0 (FeCl3) e de 7,0 a 8,0 (Al2(SO4)3; razão de gfloculante/gbiomassa de: 0,08 gorgânico/gbiomassa, 0,40gAl2(SO4)3/gbiomassa. O impacto da disponibilidade de luz no interior de fotobiorreatores foi estimada para diferentes disponibilidades de luz (108-700 ?mol.m-2.s-1) e a partir de dados de concentração celular, concentração de pigmentos e geometria do reator, sendo verificada a perda de aproximadamente 85% da luz disponível na superfície para cultivos com concentração celular de até 2 g.L-1 em fotobiorreatores de 8 cm de diâmetro. A produção de biomassa e bicombustíveis em software comercial SuperPro designer v8.5 fomos simuladas e associadas à análise econômica / Abstract: The use of microalgae in environmental carbon dioxide mitigation processes and renewable energy production are gaining attention, but the optimization of "upstream" and "downstream" process is essential to promote technical and economic feasibility and make with the industrial scale became true. The conditions that maximize biomass growth, carbon dioxide mitigation, lipid content, and produce a fatty acid profile suitable for a high quality biodiesel was evaluated as function of different temperatures (18-42 ºC), carbon availability as CO2 (air-40%), light intensity (4-192 ?mol.m-2.s-1), and nitrogen availability as NaNO3 (0.25-1.00 g.L-1). Biomass harvesting using flocculation process was evaluated as function of flocculant type (organic and inorganic), flocculant dosage (0.005-0.3 g.L-1), pH (4-11), and biomass concentration (0.1-1.0 g.L-1). The selected conditions were: 108 ?mol.m-2.s-1, 26.5 ºC and 8.05% de CO2, with the following results: Xmax/X0=14.78 (maximum and initial cell concentration ratio); ?max=1.02 d-1 (maximum specific growth rate), ?=0.50 d (lag phase duration); Pmax=0.58 g.L-1.d-1 (maximum productivity); Pmean=0.31 g.L-1.d-1 (mean productivity); CBmax=1.06 g.L-1.d-1 (maximum carbon incorporation rate); CBmean=0.55 g.L-1.d-1 (mean carbon incorporation rate); 50% of lipid content, and 90% of samples FAMES (fatty acid methyl ester) corresponding to the mainly biodiesel FAMES (C16:0, C18:0, C18:1, C18:2 e C18:3). Biodiesel quality prediction using samples of microalgae oil show the following results: CN=56 (cetane number), CFPP = 0.8 °C (could filter plugging point), ? = 863 kg/m³ (density), II = 97 gI2/100g (iodine index), ?HC = 39.2 kJ/g (heat of combustion), OSI = 13.8 h (oil stability index), and ? = 3.93 mm².s (viscosity), and the values were compatible with different quality standards ASTM-D6751, EN14214/14213, and ANP 255/2003. Recovery efficiency (RE) of 95% or more can be obtained with pH 4,0 to 11,0 (organic flocculant); 5,0 to 7,0 (FeCl3), and 7,0 to 8,0 (Al2(SO4)3; gflocculant/gbiomass of: 0,08gorganic/gbiomass, 0,40gAl2(SO4)3/gbiomass). The impact of light availability in the center of photobioreactor was predicted as function of cell concentration, pigments concentration and photobioreactor design, being observed approximately 85% of loss in the incident light availability in cultures is less than 2 g.L-1. Biomass production process and biofuels production process were simulated using a commercial software SuperPro Designer v8.5 followed by economic analysis / Doutorado / Processos em Tecnologia Química / Doutora em Engenharia Quimica

There is increasing concern regarding alternative, sustainable energy sources, such as biofuels, to replace declining oil reserves. The abundance of lignocellulosic biomass makes it the only imaginable resource that can potentially substitute a substantial portion of the fossil fuels we use today, but current methods for producing biofuels from non-food crops are cost intensive and not economically viable. Synthetic biology provides several potential approaches for developing biologically mediated processes for the conversion of lignocellulosic biomass into biofuels. Such systems are based on engineered microbes that produce enzymes for catalysing the conversion of cellulose into fermentable sugars and subsequently into high value products. Effective degradation of cellulose requires multiple classes of enzyme working together. In naturally occurring cellulose degrading microbes, bioconversion is catalysed by a battery of enzymes with different catalytic properties. However, naturally occurring cellulases with multiple catalytic domains seem to be rather rare in known cellulose-degrading organisms. Using synthetic biology approaches, seven cellulases with multiple catalytic domains were engineered and tested to determine the usefulness of such chimeric enzymes to replace cloning of multiple enzymes for biomass conversion. Catalytic domains were taken from Cellulomonas fimi endoglucanases CenA, CenB and CenD, exoglucanase Cex, and β-glucosidase, Cfbglu as well as Cytophaga hutchinsonii cellodextrinase CHU2268. All fusions retained both catalytic activities of the parental enzymes. To investigate the benefits of fusion, Citrobacter freundii NCIMB11490 was transformed with either fused or non-fused enzymes and cultured with cellulose blotting papers as main carbon source. Cells expressing fusions of Cex with CenA or CenD reproducibly showed higher growth than cells expressing non-fused versions, as well as more rapid physical destruction of paper. The opposite was observed for the other combinations. Comparing two different Cex and CenA fusions, CxnA2, which contains two carbohydrate binding modules (CBMs), degraded filter paper faster and led to better growth than CxnA1, which contains only one CBM. It was observed that CxnA1 was exported to the supernatant of E. coli and C. freundii cultures, as also seen for Cex and CenA, although there is no clear biological mechanism for this. Monitoring of growth using colony counts is laborious, but the use of optical density is not possible for cellulose-based cultures as it is affected by the insoluble cellulose particles. The SYBR Green I/propidium iodide live/dead staining protocol was therefore evaluated for growth measurements and was found to allow rapid measurements of large numbers of samples. In conclusion, these studies have demonstrated a simple and useful method for making chimeric proteins from libraries of multiple parts. The results demonstrate that use of fusion proteins can improve biomass conversion in vivo, and could potentially reduce the necessity for cloning of multiple enzymes and improve product yields. A simple and effective method for monitoring growth of bacteria in turbid cultures using a fluorimeter has also been developed.

Doctor of Philosophy / Department of Agricultural Economics / Jason S. Bergtold / Tian Xia / Brazil is one of the leading producers of ethanol, sugar, and sugarcane. Increasing demand for biofuels aligned with public policies prompted the expansion of sugarcane into the Brazilian Cerrado, particularly, into the states of Goiás and Mato Grosso do Sul. The overall purpose of this dissertation, comprised of three essays, is to understand the impacts from the sugarcane expansion on farmers, processors, and the market. At the market level, the first essay, estimates the impacts of public policies and market factors on ethanol and sugar, supply and demand, in Goiás and Mato Grosso do Sul, using three-stage least squares. Results show that ethanol supply is sensitive to public policies whereas the sugar supply is sensitive to market prices. Sugar and ethanol were found to be complementary outputs. For ethanol expansion to be sustainable the ethanol market must be developed to the extent that it relies on market factors and is no longer dependent on public policies. At the farmer level, the second essay, examines farmers' willingness to sign a sugarcane contract with a mill in the Brazilian Cerrado. A hypothetical stated choice experiment was conducted with farmers in Goiás and Mato Grosso do Sul. Respondents choose between three contracts (land rental, agricultural partnership and supply) and two optout options ("keep current contract" or "not grow sugarcane"). A single and a two opt-out random parameters models were estimated. The two opt-out model allowed for a better interpretation of the status quo. Willingness to pay, direct and cross-elasticity measures for contract attributes were calculated. Results showed that farmers prefer contracts with higher returns, shorter duration and a lower probability of late payments. Farmers seemed to prefer to renting out their land to the mill than to produce sugarcane themselves, which could lead to consequences for rural development and the sustainability of sugarcane expansion. At the processor level, the third essay investigates the impact of vertical coordination on input-oriented technical efficiency using data envelopment analysis (first stage) and a Tobit censored model (second stage). 204 Brazilian mills were considered. The second stage controlled for vertical integration as well as other characteristics of the mill. Vertical integration was measured as the percentage of total sugarcane used, supplied by mills. A negative, though minimal, relationship between vertical integration and technical efficiency was found. Hence, technical efficiency is not the major driver of vertical integration. Other vertical coordination strategies may bring more benefits in terms of technical efficiency (e.g. contracts). Drivers of vertical integration seem to vary according to the characteristics of the location of the mill.

Doctor of Philosophy / Department of Geography / Marcellus M. Caldas / Biofuel ethanol has been proposed as the most viable solution to mitigate greenhouse gas emissions (GHG) from the transportation sector; however, the impact of such production on the environment is not completely known. Environmental impacts are of more concern when ethanol production occurs in areas of high biodiversity value such as the Cerrado (Brazilian savanna). The Cerrado is a global biodiversity hotspot and an important breadbasket—at the same time, it is on a path to becoming the major sugarcane ethanol-producing region in Brazil. The main goal of this dissertation is to examine the impacts of sugarcane expansion on farmers’ land use decision processes in the Cerrado and to consider its consequences on biodiversity and the impacts of climate change. In the following chapters, land change dynamics are investigated using a combination of theory and methods from geography, GIScience, economics, and ecology. Chapter 2 presents an examination of the drivers for the sugarcane expansion. The findings suggest that the Cerrado attracted mills because of the good agricultural conditions, affordable land prices, and favorable state-level fiscal incentive policies, while factors that have prevented traditional sugarcane-producing regions from meeting the increasing demand for ethanol. Chapter 3 develops a procedure to identify intensification and extensification responses at the field level. The main finding is that extensification is the main response. Additionally, this response has a higher probability of occurrence the farther an area is from a mill. Chapter 4 applies the partial adjustment framework to understand farmers’ land use decisions regarding sugarcane production. Estimates found that price of cattle have the largest cross-price elasticity with sugarcane acreage. In addition, the results suggest that acreage of sugarcane and soybean double-crop are positively correlated. Chapter 5 focuses on the impacts of climate change on land suitability for sugarcane and amphibian species. The findings show that land suitability for sugarcane is vulnerable to climate change and that the Brazilian zoning policy for sugarcane is not addressing this issue. Additionally, amphibians are affected by climate change and conflict with areas suitable for sugarcane in climate change scenarios.

The production of biofuels and in particular bioethanol has increased rapidly since the early 1990’s. The advantages of biofuels include reduced CO2 production, a decrease in fuel importation for many nations (notably the US and Brazil), and comparatively simple blending with fossil fuels. The production of basic fuel ethanol (1st generation) involves the use of an energy crop feedstock (corn in US and sugar cane in Brazil). The feedstock is processed via simple mechanical methods to release the simple carbohydrates, mixed with water and fermented anaerobically via S. cerevisiae yeast into ethanol and CO2. Due to the low market value of fuel ethanol, profit margins are restrictive, and as a result sterilisation and aseptic techniques are not economically viable, and contamination by environmental organisms is commonplace. The current system of biocontrol involves the addition of antibiotics, primarily penicillin and virginiamycin, to the fermentation. While these antibiotics are broad spectrum and highly effective in reducing the impact of contamination, the negative environmental impacts of antibiotic usage are well known. In order to reduce the impact of contamination and reduce reliance on antibiotics an alternative system of biocontrol is required. In this thesis various biocontrol agents are assessed, including bacteriophage, hop acids, chitosan, onion oil extract, copper and silver ions. The effect of these agents on the growth of various contaminant bacteria and a strain of S. cerevisiae is assessed and fermentations are carried out under sterile and controlled contaminated conditions to generate data on the effect of the contaminant and the various methods of biocontrol. Other possibilities investigated include the insertion of plasmids containing heat shock proteins into S. cerevisiae to enhance thermo-tolerance.

Orientador: Araí Augusta Bernárdez Pécora / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-28T12:10:13Z (GMT). No. of bitstreams: 1 JimenezChacon_Suranny_M.pdf: 86052116 bytes, checksum: 756e1de65a13a7a1cea018a1ed3d9ff2 (MD5) Previous issue date: 2015 / Resumo: Uma vez que o desafio das novas gerações de pesquisadores é encontrar combustíveis renováveis e não agressivos ao meio ambiente, com propriedades similares ou superiores às dos combustíveis fósseis não renováveis, a busca por uma forma alternativa de combustível é cada vez mais recorrente. Visto que os recursos fósseis estão cada vez mais escassos, pode-se considerar que a busca de combustíveis alternativos é um desafio que marca a atualidade, pois consequentemente impulsiona o desenvolvimento de ideias inovadoras com a finalidade de substituir os combustíveis utilizados tradicionalmente. Sendo assim, uma linha de pesquisa que emerge oferecendo uma proposta a este problema é aquela baseada na utilização de biomassas para geração de biocombustíveis. Dado estes fatos, o objetivo deste projeto é estudar experimentalmente a pirólise lenta de bambu da espécie Dendrocalamus giganteus Munro em reator mecanicamente agitado, visando determinar o rendimento dos produtos (carvão vegetal, líquido e gás) para cada condição ensaiada e, posteriormente, avaliar as propriedades físico-químicas do bio-óleo gerado na condição em que ocorreu seu máximo rendimento. O bio-óleo foi coletado de forma fracionada em quatro diferentes faixas de temperatura (20 ¿ 220 ºC, 220 ¿ 300 ºC, 300 ¿ 400 ºC e 400 ¿ 500 ºC) com o objetivo de verificar os rendimentos e propriedades do líquido gerado em cada uma dessas faixas de temperatura. A descoberta de possíveis aplicações para o bio-óleo do bambu contribuiria para a viabilidade econômica do processo de produção de carvão de bambu, produto principal em reatores de pirólise lenta. Os ensaios de pirólise foram feitos seguindo um planejamento experimental 2^2 mais pontos centrais (DOE ¿ Design of experiments), com a finalidade de determinar a influência da velocidade de agitação (20 a 60 rpm) e do tempo de residência (10 a 30 min) sobre o rendimento do bio-óleo gerado. Os resultados indicaram que o melhor rendimento do bio-óleo (~ 53 %) ocorreu na condição em que a agitação do rotor estava em 60 rpm e 30 min de tempo de residência do sólido. O maior PCS do bio-óleo foi de 28,7 MJ/kg, correspondente à fração coletada entre 300 e 400 ºC / Abstract: Once the challenge of new generations of researchers is to find renewable fuels that are not harmful to the environment, and showing properties similar or superior to those of non-renewable fossil fuels, the search for an alternative form of fuel is becoming more recurrent. Since the fossil resources are increasingly scarce, it can be considered that the search for alternative fuels is a challenge that marks the present time, because it consequently drives the development of innovative ideas in order to replace the traditional fuels. Thus, a line of research that emerges offering a proposal to this problem is based on the use of biomass for generating biofuels. Given these facts, the aim of this project is to study, experimentally, the slow pyrolysis of bamboo Dendrocalamus giganteus Munro in a mechanically agitated reactor, in order to determine the yield of products (charcoal, bio-oil and gas) for each test condition and subsequently evaluate the physicochemical properties of bio-oil generated in the condition in which the maximum efficiency occurred. The bio-oil was collected in separated portions at four different temperature ranges (20 ¿ 220 ºC, 220 ¿ 300 ºC, 300 ¿ 400 ºC e 400 ¿ 500 ºC) in order to verify yield and properties in each of these temperature ranges. The discovery of possible applications for the bamboo bio-oil will contribute to the economic viability of production process of bamboo charcoal, the main product of slow pyrolysis reactors. The pyrolysis experimental tests were made following a factorial design 2^2 more central points (DOE - Design of Experiments), with the purpose of determining the influence of agitation speed (20 to 60 rpm) and residence time (10 to 30 min) on yield generated from the process. The results indicated that the best bio-oil yield (~ 53 %) occurred in the condition in which the rotor agitation was 60 rpm and the solid residence time was 30 min. The highest heating value of the bio-oil was 28,7 MJ/kg, corresponding to the fraction collected between 300 and 400 °C / Mestrado / Termica e Fluidos / Mestra em Engenharia Mecânica

A jet-stirred reactor was designed and constructed in the Clean Combustion Research Center (CCRC) at King Abdullah University of Science and Technology (KAUST); was validated with n-heptane, iso-octane oxidation and cyclohexene pyrolysis. Different configurations of the setup have been tested to achieve good agreement with results from the literature. Test results of the reactor indicated that installation of a pumping system at the downstream side in the experimental apparatus was necessary to avoid the reoccurrence of reactions in the sampling probe. Experiments in ethyl levulinate oxidation were conducted in the reactor under several equivalence ratios, from 600 to 1000 K, 1 bar and 2 s residence time. Oxygenated species detected included methyl vinyl ketone, levulinic acid and ethyl acrylate. Ethylene, methane, carbon monoxide, hydrogen, oxygen and carbon dioxide were further quantified with a gas chromatography, coupled with a flame ionization detector and a thermal conductivity detector. The ethyl levulinate chemical kinetic model was first developed by Dr. Stephen Dooley, Trinity College Dublin, and simulated under the same conditions, using the Perfect-Stirred Reactor code in Chemkin software. In comparing the simulation results with experimental data, some discrepancies were noted; predictions of ethylene production were not well matched. The kinetic model was improved by updating several classes of reactions: unimolecular decomposition, H-abstraction, C-C and C-O beta-scissions of fuel radicals. The updated model was then compared again with experimental results and good agreement was achieved, proving that the concerted eliminated reaction is crucial for the kinetic mechanism formulation of ethyl levulinate. In addition, primary reaction pathways and sensitivity analysis were performed to describe the role of molecular structure in combustion (800 and 1000 K for ethyl levulinate oxidation in the jet-stirred reactor).

Diploma thesis is focused on the treatment of biofuel prior to combustion and effect of this treatment on the biofuel characteristics. The first part is a review of literature encompassing characteristics of fuel, preparation of samples, methods of analysis of individual characteristics and a presentation of various types of mills. The second part of thesis is experimental. It is an analysis of sample characteristics under various mill settings with regard to the temperature in the mill during grinding.

Phospholipid bilayers are the principal component of the cell membrane. Membranes ensure the maintenance of processes required for cells’ survival by regulating the inflow and outflow of nutrients and other molecules using membrane proteins. However, studying the cell membrane is challenging because of its complexity and small size. In-vitro membrane models made of phospholipids are important tools for studying membranes. In this work, we aim to study the fluidity of phospholipid bilayers of different lipids using general polarization (GP) of the fluorescent probe Laurdan as a measure. We will focus on the relative importance of head groups and fatty acids in the phospholipid. For this purpose, we are synthesizing chimeric lipids with the common human head group phosphocholine paired with bacterial fatty acids. We will compare the response of the human and chimeric lipids to temperature and biofuels to ascertain whether improved stress tolerance can be obtained with the chimeras.

This master’s thesis is aimed at process of enzymatic hydrolysis of lignocellulosic material – waste paper as a source of raw material for production of liquid biofuels. In the theoretical part of this work are summarized previously used methods of hydrolysis and lignocellulosic materials used for the process of hydrolysis as a source of fermentable sugars for fermentation technology. The different types of waste paper are evaluated from the composition and usability with consideration to the papermaking process in order to select the appropriate type of waste paper for the enzymatic hydrolysis process. In the next part of this work are suggested technological premises and procedures for the preparation of raw materials and the subsequent enzymatic hydrolysis of these pre–treated materials. In the experimental part were optimized parameters of enzymatic hydrolysis using the Novozymes company enzyme package. Enzymatic degradation of cellulose to reducing sugars was observed using Somogyi – Nelson method. For the verification of hydrolysis conditions were used model materials with high cellulose content – pulp and filter paper. Conditions, which seems to be the best after testing on the model materials, were verified on specific waste paper materials – offset cardboard, recycled paper, matte MYsol paper and for comparison again on model materials – pulp and filter paper. The highest yields was achieved with the use of cardboard, which was further tested using various combinations of pretreatment to material for purpose of increase the yields of hydrolysis.