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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.
1

Production of ethanol from molasses using the thermotolerant yeast strain Kluyveromyces marxianus IMB3

Gough, Suzanne January 1998 (has links)
No description available.
2

Study of Ultrasonic Treatment of Clostridium on Bio-hydrogen Producing Effect

Kuo, Huan-Chen 29 August 2012 (has links)
The resources on earth are limited; thus, the demand for energy, goods and materials is surging because of the growth of the advanced technology and population. The issues of using the resources effectively and changing them into a useful energy are then important. Taiwan creates a vast amount of agricultural waste every year. The traditional way of eliminating the agricultural waste would be burned and buried. However, it is not only the agricultural waste cannot be reused and recycled, but also the problem of air pollution occurred. The objectives of this thesis are thus to transfer the agricultural waste into a useful energy. This study contents two parts. The first part changes the agricultural waste into sugar. The agricultural waste is full of wood fiber and can be transformed to sugar by a microorganism method. A cane which is a common agricultural waste is used; the wood fiber in cane will be added to the thermostable cellulolytic bacterial Geobacillus thermoleovorans T4 isolated from sugar refinery wastewater in southern Taiwan. T4 can convert wood fiber into sugar. Experimental results showed that the rate of reducing sugar is 13.77%. The second part studies the biological hydrogen production by Clostridium acetobutylicum ATCC 824, and the sugar will be added into the process. Also, this study uses ultrasonic treatment in the biological hydrogen production and calculates the natural frequency of ATCC 824. The experiment is designed using the Taguchi method for increasing hydrogen production, hydrogen production rate and hydrogen production efficiency by using an ultrasonic treatment to treat C. acetobutylicum ATCC 824. It is showed that the best combination is temperature 37¢XC, ultrasonic frequency 0.5 MHz, ultrasonic intensity 136 mW/cm2, exposure time 10 s, pH 7.5 and bacterial concentration 20%. This study can apply in bio-energy and fermentation food producing.
3

Comparative life cycle assessment of rice husk utilization in Thailand

Prasara-A, Jittima, s3126806@student.rmit.edu.au January 2010 (has links)
Thailand is one of the largest rice producing nations in the world. Moreover, there is a trend for Thai rice exports to increase. This could imply that if the trend continues, there will be an increased quantity of rice husk in the future. Rice husk is a co-product of rice products generated in the rice milling process, accounting for about 23 percent of the total paddy weight. To make use of this large quantity of rice husk, the husk has traditionally been used as an energy source in the rice mills themselves. More recently, the Thai government has promoted the use of biomass to substitute for fossil fuel consumption and to reduce the environmental impacts caused by using fossil fuels. Therefore, rice husk, which is one of the main sources of biomass in Thailand, has already been used on a commercial scale. However, the environmental impacts associated with different rice husk applications have not yet been widely investigated in the Thai context. While there is a need to find ways of dealing with rice husk disposal, it is also important to ensure that this husk is used in ways that harm the environment least. This research aims to identify the most environmentally friendly use of rice husk for Thailand. To achieve this, the research is divided into three main stages; identification of main current and potential uses of rice husk in Thailand; data collection; and data analysis using Life Cycle Analysis approach. A range of methods such as literature review, questionnaires with rice mill owners, and interviews with industry personnel, were used to help in identifying the current and potential uses of rice husk. The major current and potential rice husk uses chosen to be examined in this research are those uses of rice husk in electricity generation, in cement manufacture and in cellulosic ethanol production. The second stage is to collect detailed data about the processes of the selected rice husk uses to be examined. This was undertaken by literature review, questionnaires and interviews with involved industry personnel. The last stage is to analyse the data collated. Life Cycle Assessment (LCA) approach and the L CA software package SimaPro (version 7.1.6) were used to assess the environmental impacts of the selected rice husk uses. Results from the LCA are reviewed in the context of critical policy issues, including the Thai government biomass policies; the capacity of the production process of rice husk use options; and the infrastructure availability and practicality of the rice husk use options. Based on the goal and scope of the study, the data available for this study and the review of the issues just mentioned, it is concluded that, in the short term, the most practical environmentally friendly use of rice husk across the three uses investigated is the use of rice husk in electricity generation. However, with expected oil shortages in the future, rice husk should also be considered for use in cellulosic ethanol production, as this option helps to save some amount of petrol.
4

Release and Transport of Bacteria and Nutrients from Livestock Manure Applied to Pastureland

Soupir, Michelle Lynn 03 September 2003 (has links)
Transport of fecal bacteria and nutrients from point and nonpoint sources to surface water bodies is of significant concern in Virginia and the United States. In Virginia, 4,320 river miles are impaired for one or more beneficial use and 72% of the streams are impaired due to pathogen indicators (VDEQ, 2002). Land applications of manure from confined animal systems and by direct deposit by grazing animals are both major sources of fecal bacteria and nutrients in runoff. Therefore, an understanding of the overland transport mechanisms for fecal bacteria and nutrients is very important for the development of best management practices to reduce loading of pathogens and nutrients to surface water bodies. The objectives of this study were to quantify the release and transport potential of three fecal bacterial indicators: E. coli, Enterococcus, and fecal coliforms; and nitrogen and phosphorus from land applied manure during runoff events. Another objective was to identify the Enterococcus species present in dairy manure and determine which species have the highest potential to be transported by runoff. Release plots were established to study the in-field bacteria and nutrient release. The bacteria and nutrients released from the plots are available to be transported to the edge of the field in runoff. Four manure treatments (turkey litter, liquid dairy manure, cowpies, and none or control) and three land type treatments: pasture with a history of poultry litter application (Turkey Farm), pasture with a history of liquid dairy manure application (Dairy Farm), and pasture with no prior manure application (Tech Research Farm) were studied. During a short but intense rainfall event, the highest bacterial release was measured under the cowpie treatment (E. coli concentrations ranging from 37,000 to >300,000 and FC concentrations ranging from 65,000 to >300,000). Pasturelands with a history of previous manure applications did not release higher bacteria concentrations compared with pasturelands which had never received manure applications. Pasturelands with a history of land application of liquid dairy manure and turkey litter had 143% and 94% higher TSS concentrations available to be transported off the field during overland flow events because of the build up of organic material on the soil surface. TP concentrations released from the cowpie, liquid dairy, and turkey litter treatments were 3.12 mg/L, 3.00 mg/L, and 1.76 mg/L, respectively. Transport plots were developed to measure the concentrations of fecal bacteria and nutrients present in overland flow at the edge of the field. The bacteria flow-weighted concentrations were highest in runoff samples from the plots treated with cowpies (200,000 CFU/100 mL of E. coli and 234,000 CFU/100 mL of FC). The turkey litter had the highest concentration of dissolved phosphorus in runoff from pasturelands (1.22 mg/L), but the cowpie treatment had the highest concentrations of sediment bound phosphorus in runoff (0.73 mg/L). All three treatments investigated in this study contributed to phosphorus loading in surface waters and could potentially increase the risk of eutrophication. Total nitrogen concentrations from the transport plots exceeded the threshold for likely eutrophication problems for all treatments and the total nitrogen concentrations from plots treated with cowpies exceeded the threshold for severe eutrophication problems. The Biolog System, a method of bacterial source tracking, was used to identify the different species of Enterococcus present both in the cowpie source manure and in the runoff collected from the transport plots treated with cowpies. The source manure is dominated by the Enterococcus mundtii (55%), Enterococcus gallinarum (20%), Enterococcus faecium (10%), and Enterococcus faecalis (10%). Enterococcus faecalis had the highest percentage of isolates present in runoff with a total of 37%, followed by Enterococcus mundtii which was present in 21% of the runoff events and Enterococcus gallinarum and Enterococcus faecium (11%). Improvements in understanding the bacterial release and overland processes will enhance modeling of bacteria and nutrient transport, and provide a basis for a more realistic evaluation of the impacts of management practices implementation. The data from this study will serve as a baseline to model the release and transport of fecal bacteria and nutrients from agricultural watersheds to surface waters. / Master of Science
5

A catchment approach to managing agricultural pesticides in the environment : a case study with the herbicide atrazine

Popov, Vladislav H., University of Western Sydney, College of Science, Technology and Environment, School of Environment and Agriculture January 2005 (has links)
Surface water quality of the Liverpool Plains (NSW), a series of floodplains comprising the floodplain of the Mooki River, is poor despite the introduction of conservation tillage that has reduced soil erosion and, with it, the transport of sediment, nutrients and chemicals to streams.The aim of this thesis was to provide a basis for recommending the possible wider use of biofilters, by determining their effectiveness in reducing pollutant (mainly atrazine) transport at multiple scales in the Liverpool Plains, quantifying the importance of relevant processes, including the capacity of soil biofilters to degrade the retained pollutants, and evaluating the effect of pollutants on the biofilter vegetation. These objectives were explored in two sub-catchments within the Liverpool Plains, namely Big Jacks Creek and the Blackville.Soils are predominantly vertosols that crack deeply on drying, resulting in initially high infiltration rates on wetting and high water holding capacity. Field monitoring revealed that biofilters such as grassed waterways, natural grasslands or vegetated filter strips (VFS) positioned at multiple catchment scales can significantly reduce pollutant concentrations in runoff. The use of biofilters is discussed, along with other best management practices that will be needed to manage pesticide loads both at source and in the transport pathway. / Doctor of Philosophy (PhD)
6

Xylan-based Biodegradable And Wheat Gluten-based Antimicrobial Film Production

Karamanlioglu, Mehlika 01 February 2008 (has links) (PDF)
In the first part of the study, birchwood xylan-lignin film formation was studied. After film forming effect of lignin on pure birchwood xylan was demonstrated, the minimum lignin concentration necessary to form films was determined as 1.1% (lignin/xylan). So, it was determined that keeping about one percent lignin in xylan (w/w) was sufficient for film formation. Biodegradability of the lignin-birchwood xylan composite films was investigated enzymatically using 0.21 U / ml xylanase in an accelerated test. All the films containing lignin were hydrolyzed by xylanase showing biodegradability of the films. Colors of the birchwood xylan-lignin composite films containing different lignin concentrations were compared. Deviations of the color from the reference color were similar between the films. In the second part of the study, photocatalytic antimicrobial film production was investigated on wheat gluten-based films. In order to produce antimicrobial films, wheat gluten films were coated with a semiconductor, titanium dioxide (TiO2), applying different procedures. Coated films were illuminated and photocatalytical inactivation of Escherichia coli on films were determined by antimicrobial tests. The coating procedure in which titanium dioxide (TiO2) was produced from titanium tetraisopropoxide (TTIP) in aqueous-nitric acid and aqueous-hydrochloric acid solutions gave the best antimicrobial result but the films turned out to be deformed and brittle. Spreading TiO2 sol-gel on semi-dried wheat gluten films resulted in flexible and undeformed films having about 40% antimicrobial activity.
7

Estudo da Ocorrência de Isoflavonas em Resíduos da Cultura de Soja

Carneiro, Ariadne Magalhães January 2018 (has links)
Orientador: Cristiano Soleo de Funari / Resumo: Aproximadamente 3,7 x 109 toneladas de resíduos agrícolas são produzidos anualmente no mundo. Por ser uma das grandes potências agrícolas atualmente, grandes quantidades de resíduos agrícolas são geradas constantemente no Brasil. Uma das principais culturas produzidas no país é a soja. Além de seu uso na pecuária, utilizada na alimentação animal, assim como para alimentação humana, a soja desperta grande interesse do ponto de vista farmacológico, por ser uma das principais fontes de isoflavonas, uma forma de fitoestrogênio, sendo umas das espécies listadas na RENISUS. Este trabalho teve como objetivo investigar o perfil químico dos resíduos provenientes da cultura da soja (caules, folhas e vagens) por meio de uma abordagem analítica verde. Os extratos foram obtidos em triplicata por maceração dinâmica a 30 °C, com acetona e etanol, com e sem adição de ácido. O solvente acetonitrila foi utilizado como solvente de referência, pois é comumente empregado tanto para a extração como para a separação de isoflavonas presentes em grãos de soja. Os extratos foram analisados por cromatografia líquida de alta eficiência acoplada a um espectrofotômetro de untravioleta/visível (HPLC-PAD/UV) e a comparação da eficiência de extração entre os solventes testados foi feita com base em número total de picos, área total sob os picos e rendimento da extração. Os solventes verdes etanol e acetona mostraram-se mais eficientes do que o solvente de referência acetonitrila. Posteriormente, uma estratég... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Approximately 3.7 x 109 tonnes of agricultural waste is produced annually in the world. Because it is one of the great agricultural powers today, large amounts of agricultural residues are constantly generated in Brazil. One of the main crops produced in the country is soy. In addition to its use in livestock and human nutrition, the soybean awakes great interest from the pharmacological point of view, being one of the main sources of isoflavones, a form of phytoestrogen, being one of the species listed in RENISUS. The objective of this work was to investigate the chemical profile of residues from soybean (shoots, leaves and pods) using a green analytical approach. The extracts were obtained in triplicate by dynamic maceration at 30 ° C, with acetone and ethanol, with and without acid addition. The solvent acetonitrile was used as reference solvent, since it is commonly used both for the extraction and the separation of isoflavones present in soybean grains. The extracts were analyzed by high performance liquid chromatography coupled to an untraviolet/visible spectrophotometer (HPLC-PAD/UV) and the comparison of the extraction efficiency among the solvents tested was done based on total number of peaks, total area under peaks and extraction yield. The green solvents ethanol and acetone were more efficient than the reference solvent acetonitrile. Subsequently, a strategy for the identification of compounds in mixture, based on data obtained by high performance liquid chromatog... (Complete abstract click electronic access below) / Mestre
8

Resíduos agroindustriais utilizados para produção de tanase por aspergillus sp isolado da caatinga do Nordeste Brasileiro

Katarina Botelho de Melo Nascimento 11 December 2013 (has links)
A utilização de resíduos agroindustriais na produção de diversos bioprodutos tem surgido como uma alternativa viável, para o aproveitamento na formação de subprodutos através da bioconversão de resíduos agroindustriais que estão cada vez mais utilizados. Os resíduos se caracterizam como materiais extremamente heterogêneos, e que servem tanto como fonte de carbono e energia, quanto para o crescimento microbiano, reduzindo assim os custos de produção de diversas enzimas microbianas e minimizando o impacto ambiental que esses materiais ocasionariam ao serem descartados no meio ambiente. Os fungos filamentosos apresentam um elevado potencial biotecnológico para produção de enzimas de origem microbiana. As tanases são enzimas extracelulares que catalisam a quebra de taninos hidrolisáveis, induzíveis, produzidas por diversos micro-organismos, principalmente por fungos filamentosos, por fermentação sólida, líquida ou submersa, com vasta aplicação em diversos seguimentos de origem industrial e comercial. Este trabalho apresenta uma proposta de formular meios considerados econômicos para produção de tanases utilizando resíduos agroindustriais (café, uva e laranja) pelo fungo filamentoso Aspergillus isolado da caatinga do estado de Pernambuco. A primeira etapa da pesquisa consistiu na seleção do fungo, onde ele apresentou atividade degradadora do ácido tânico, porém a linhagem que apresentou melhor atividade foi o SIS 4. Essa linhagem, posteriormente, foi testada em meios de cultura adicionando 10 g/L de resíduos agroindustriais a uma solução de sais contendo 10 g/L de ácido tânico. Os melhores resultados foram obtidos com o resíduo de café para a linhagem previamente selecionada. / The use of agro-industrial waste in the production of various bioproducts has emerged as a viable alternative for use in the formation of by-products through bioconversion of agro-industrial waste that are increasingly used. The waste material is characterized as highly heterogenous, and they serve both as a source of carbon and energy, as for microbial growth thus reducing the production costs of several microbial enzymes and minimizing the environmental impact that these materials would provoke to be disposed in the environment. Filamentous fungi has a high potential for biotechnological production of enzymes of microbial origin. The tanases are extracellular enzymes that catalyze the cleavage of hydrolyzable tannins, inducible produced by various microorganisms, mainly by filamentous fungi , for ferment solid, liquid or submerged in a wide application in various segments of origin industrial and commercial. This work presents a proposal to formulate considered economical means for tannase production using agroindustrial waste (coffee, grape and orange) by the filamentous fungus Aspergillus isolated from the caatinga of Pernambuco state. The first stage of the research consisted in the selection of the fungus, where he was active degrading tannic acid, but the strain that showed the best activity was the SIS 4. This strain was subsequently tested in culture media by adding 10 g/L of the agroindustrial waste salt solution containing 10 g /L tannic acid. The best results were obtained with the residue of coffee to the line previously selected.
9

Estudo da Ocorrência de Isoflavonas em Resíduos da Cultura de Soja / Study of the Occurrence of Isoflavones in Soybean Crop Residues

Carneiro, Ariadne Magalhães 19 April 2018 (has links)
Submitted by ARIADNE MAGALHÃES CARNEIRO (ariadnemagcar@hotmail.com) on 2018-06-17T22:48:50Z No. of bitstreams: 1 Dissertação Ariadne Magalhães Carneiro Versão Corrigida 4.pdf: 2192618 bytes, checksum: 14dd0c6daab475134d8c57af4f4d517f (MD5) / Approved for entry into archive by Sulamita Selma C Colnago null (sulamita@btu.unesp.br) on 2018-06-18T20:32:00Z (GMT) No. of bitstreams: 1 carneiro_am_me_bot.pdf: 2192618 bytes, checksum: 14dd0c6daab475134d8c57af4f4d517f (MD5) / Made available in DSpace on 2018-06-18T20:32:00Z (GMT). No. of bitstreams: 1 carneiro_am_me_bot.pdf: 2192618 bytes, checksum: 14dd0c6daab475134d8c57af4f4d517f (MD5) Previous issue date: 2018-04-19 / Aproximadamente 3,7 x 109 toneladas de resíduos agrícolas são produzidos anualmente no mundo. Por ser uma das grandes potências agrícolas atualmente, grandes quantidades de resíduos agrícolas são geradas constantemente no Brasil. Uma das principais culturas produzidas no país é a soja. Além de seu uso na pecuária, utilizada na alimentação animal, assim como para alimentação humana, a soja desperta grande interesse do ponto de vista farmacológico, por ser uma das principais fontes de isoflavonas, uma forma de fitoestrogênio, sendo umas das espécies listadas na RENISUS. Este trabalho teve como objetivo investigar o perfil químico dos resíduos provenientes da cultura da soja (caules, folhas e vagens) por meio de uma abordagem analítica verde. Os extratos foram obtidos em triplicata por maceração dinâmica a 30 °C, com acetona e etanol, com e sem adição de ácido. O solvente acetonitrila foi utilizado como solvente de referência, pois é comumente empregado tanto para a extração como para a separação de isoflavonas presentes em grãos de soja. Os extratos foram analisados por cromatografia líquida de alta eficiência acoplada a um espectrofotômetro de untravioleta/visível (HPLC-PAD/UV) e a comparação da eficiência de extração entre os solventes testados foi feita com base em número total de picos, área total sob os picos e rendimento da extração. Os solventes verdes etanol e acetona mostraram-se mais eficientes do que o solvente de referência acetonitrila. Posteriormente, uma estratégia de identificação de compostos em mistura, baseada em dados obtidos por cromatografia líquida de alta eficiência acoplada a espectrometria de massas de alta resolução (HPLC-PDA/UV-ESI/TOF/MS) e em dados quimiotaxonômicos foi empregada. Foram identificadas as isoflavonas não glicosiladas daidzeína, genisteína e gliciteína, além da flavona apigenina, em resíduos de cultura de soja. Este trabalho sugere que isoflavonas e outros flavonóides poderiam ser obtidos de resíduos agrícolas da cultura de soja, amplamente disponíveis mundialmente, por meio de tecnologias verdes de extração e de análise. / Approximately 3.7 x 109 tonnes of agricultural waste is produced annually in the world. Because it is one of the great agricultural powers today, large amounts of agricultural residues are constantly generated in Brazil. One of the main crops produced in the country is soy. In addition to its use in livestock and human nutrition, the soybean awakes great interest from the pharmacological point of view, being one of the main sources of isoflavones, a form of phytoestrogen, being one of the species listed in RENISUS. The objective of this work was to investigate the chemical profile of residues from soybean (shoots, leaves and pods) using a green analytical approach. The extracts were obtained in triplicate by dynamic maceration at 30 ° C, with acetone and ethanol, with and without acid addition. The solvent acetonitrile was used as reference solvent, since it is commonly used both for the extraction and the separation of isoflavones present in soybean grains. The extracts were analyzed by high performance liquid chromatography coupled to an untraviolet/visible spectrophotometer (HPLC-PAD/UV) and the comparison of the extraction efficiency among the solvents tested was done based on total number of peaks, total area under peaks and extraction yield. The green solvents ethanol and acetone were more efficient than the reference solvent acetonitrile. Subsequently, a strategy for the identification of compounds in mixture, based on data obtained by high performance liquid chromatography coupled to high resolution mass spectrometry (HPLC-PDA/UV-ESI/TOF/MS) and chemotaxonomic data was used. The non-glycosylated isoflavones daidzein, genistein and glycitein, as well as flavone apigenin, were identified in soybean residue. This work suggests that isoflavones and other flavonoids could be obtained from soybean crop residues widely available worldwide through green extraction and analysis technologies.
10

Estudo de viabilidade do emprego de lodo de esgoto e resíduos agrícolas para a geração de bioenergia / Feasibility study of the use of sewage sludge and agricultural residues for bioenergy generation

Torquato, Lilian Danielle de Moura [UNESP] 12 December 2016 (has links)
Submitted by Lilian Danielle de Moura Torquato null (litorquato.ibilce@gmail.com) on 2016-12-19T19:48:44Z No. of bitstreams: 1 Tese_ L.D.M. Torquato (12-12-2016)_DEFINITIVA.pdf: 6366289 bytes, checksum: b0113724fd68a4c4328ce9913a55d99b (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-21T11:15:51Z (GMT) No. of bitstreams: 1 torquato_ldm_dr_araiq.pdf: 6366289 bytes, checksum: b0113724fd68a4c4328ce9913a55d99b (MD5) / Made available in DSpace on 2016-12-21T11:15:51Z (GMT). No. of bitstreams: 1 torquato_ldm_dr_araiq.pdf: 6366289 bytes, checksum: b0113724fd68a4c4328ce9913a55d99b (MD5) Previous issue date: 2016-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo deste trabalho foi avaliar a viabilidade do emprego de lodo anaeróbio, originados pelo processo de tratamento de efluentes sanitários, como biomassa para a geração de energia, o qual foi realizada por diferentes processos de conversão: por combustão, sendo este resíduo aplicado isoladamente ou co-processados com bagaço de cana-de-açúcar; por digestão anaeróbia, aplicando-o como inóculo para a produção biológica de hidrogênio. No processo termoquímico, avaliou-se o desempenho térmico e cinético das biomassas citadas, bem como de suas misturas (“blendas”) em diferentes proporções. Os estudos demonstraram que as blendas, apesar da influência das biomassas precursoras, apresentaram propriedades térmicas distintas destas durante o processo de combustão e dependentes da razão de aquecimento empregadas. Em termos de conteúdo energético, inerentemente, o poder calorífico das blendas cresce com a quantidade de bagaço adicionado, que contribui para o aumento da reatividade destes materiais durante a devolatilização. Entretanto, para a combustão em grande escala, a adição de 75% de bagaço ao lodo não se mostrou viável, por levar ao aumento da energia de ativação (Ea) durante o processo. Por outro lado, apesar de necessitar de maior Ea inicialmente, o lodo demonstrou maior estabilidade ao longo do processo, sugerindo sua capacidade de manter o mesmo rendimento por maior tempo. Os estudos preliminares de emissões gasosas demonstraram um perfil inesperado para a blenda com maior proporção de bagaço, o qual pode ser um reflexo dos resultados obtidos durante a caracterização térmica das biomassas avaliadas. Quanto à abordagem bioquímica, foram realizados ensaios voltados à geração de H2 por meio da digestão anaeróbia, empregando o lodo como inóculo e, como substrato, meio de cultura sintético e efluentes da indústria de processamento de frutas cítricas (a água residuária e a vinhaça citrícola). Este estudo demonstrou a potencialidade de ambos os efluentes citrícolas como substratos, bem como reiteraram a viabilidade de aplicação prática do lodo de esgoto LG para a produção biológica de H2, a qual já havia sido comprovada em meio sintético, inclusive em concentrações crescente de sacarose. Este inóculo apresentou maior potencial biológico quando comparado a amostras de lodo de diferentes sistemas de tratamento de efluentes da região de Araraquara. Paralelamente, foi desenvolvido um método termogravimétrico para a análise imediata de biomassas (umidade, materiais voláteis, carbono fixo e cinzas), no qual foi possível a avaliação de todas as referidas propriedades em uma única medida, realizada em um tempo consideravelmente mais curto em relação a métodos padrão. O método desenvolvido foi validado e aplicado a diferentes tipos de biomassas, demonstrando ser preciso mesmo quando aplicado a uma matriz complexa, como o lodo de esgoto. Em todos os estudos, ficou clara a importância da análise térmica para a caracterização destes resíduos quando se propõe sua aplicação energética, haja visto que fornece parâmetros que servem de base à compreensão dos fatores preponderantes para a futura implantação destes em processos em larga escala. As informações fornecidas por este trabalho certamente podem contribuir para agregar valor a materiais outrora tidos como rejeitos, promovendo-os a fontes potenciais de energia (biomassa) renovável e até mesmo limpa (H2), com alta disponibilidade e custo reduzido. / The aim of this study was to evaluate the feasibility of using the anaerobic sludge generated by the treatment of sanitary effluents, as biomass for power generation, which was carried out by different conversion processes: combustion, by applying this residue single or co-processed with sugar cane bagasse; anaerobic digestion, by applying sludge as inoculum for the biological production of hydrogen. In the thermochemical process, the thermal and kinetic performance of the related biomasses, as well as of their mixtures ("blends") were evaluated in different proportions. The studies showed that the blends had different thermal properties during combustion process despite the influence of the precursor biomass, which dependes on the heating rate employed. In terms of energy content, inherently, the heating value of the blends increases as increases the amount of bagasse, which contributes to increase the reactivity of these materials during devolatilization. However, for large-scale combustion, the addition of 75% of bagasse to the sludge was not feasible, since it results in a increase of the activation energy (Ea) during the process. On the other hand, despite the need for a greater input of Ea, the sludge showed greater stability throughout the process, suggesting its capacity to maintain the same yield for a longer time. Preliminary studies of gaseous emissions showed an unexpected profile for the blend with the highest bagasse ratio, which may be a reflection of the results obtained during the thermal characterization of the evaluated biomasses. Regarding the biochemical approach, tests were performed to generate H2 by anaerobic digestion, using sludge as inoculum and, as substrate, synthetic medium and effluents from the citrus processing industry (the wastewater and the citrus vinasse). This study demonstrated the potential of both citrus effluents as substrates, as well as reaffirm the feasibility of practical application of LG sewage sludge to the biological production of H2, which have already been proven in synthetic medium, even in increasing concentrations of sucrose. This inoculum presented higher biological potential when compared to sludge samples from different effluent treatment systems of the region of Araraquara. In parallel, a thermogravimetric method was developed for the proximate analysis of biomasses (moisture, volatile matter, fixed carbon and ash), which enables the direct evaluation of all these properties in a single measurement, carried out in a considerably shorter time in relation to standard methods. The developed method was validated and applied to different types of biomass, showing to be accurate even when applied to a complex sample as sewage sludge. In all studies, it became clear the importance of thermal analysis for the characterization of these residues when it is proposed their energetic application, given that it provides parameters that serve as a basis for the understanding of the prevailing factors for the future application of these materials in large scale processes. The information provided by this work can certainly contribute to add value to materials once considered as tailings, turning them into potential sources of renewable and even clean energy (H2), with high availability and low cost.

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