Orientador: Caio Glauco Sanchez / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-08-08T20:26:18Z (GMT). No. of bitstreams: 1 Camargo_FernandodeLima_D.pdf: 7117474 bytes, checksum: 1af76a6da86b0eb0088d549b41f7ed5f (MD5) Previous issue date: 2006 / Resumo: O conteúdo de energia da biomassa pode ser explorado por combustão direta ou outros processos de conversão: físicos, biológicos e termoquímicos. Entre os processos termoquímicos há a pirólise que é atrativa devido à conversão de biomassa sólida para produtos líquidos apresentando algumas vantagens tais como no transporte, no armazenamento, na manufatura, reprocessamento e flexibilidade na produção. O objetivo deste trabalho foi construir e operar um reator de leito fluidizado em escala de bancada com alimentação contínua de biomassa para converter o bagaço de cana de açúcar em líquidos via pirólise rápida. O reator construído tem 0,095 m de diâmetro interno e foi utilizado areia fina como material inerte. Foi desenvolvido um novo alimentador para controlar a alimentação contínua de biomassa no leito e um sistema isocinético de amostragem com o objetivo de quantificar os produtos gerados no processo. Uma metodologia experimental foi escrita para a realização de testes de pirólise rápida de biomassa. Experimentos foram realizados usando catalisadores de craqueamento de petróleo (FCC) e injeção de água no fluxo para avaliar a influência destes fatores no processo. Temperatura e altura estática do leito também foram consideradas neste estudo. A altura estática do leito e a temperatura foram as variáveis mais relevantes na maioria dos testes realizados e necessitam de atenção especial na conversão para produtos líquidos / Abstract: The energy content of biomass can be exploited by direct combustion or after conversion by physical, biological and thermochemical processes. Among the thermochemical processes there is the pyrolysis that is an attractive process because it provokes the conversion of solid biomass into liquids products. Such conversion presents many advantages in transport, storage, handling, retrofitting, combustion and flexibility in production and marketing. The goal of this work was to build and operate a bench scale fluidized bed reactor to convert sugarcane bagasse into liquid products by fast pyrolysis. The reactor design presents 0,095 m internal diameter and fine sand was used as inert material for the fluidized bed. A new hopper to control the continuous feed of biomass in the reactor and an isokinetic sampling device to quantify the products obtained in the process. An experimental methodology was written for tests with biomass. Experimental essays carried out with fluid catalytic cracking and water injection in the stream in order to verify these effects in the process. Temperature and static height of the bed was also considered in this study. The static height of the bed and the temperature were the variables more important, requiring special attention in the conversion process / Doutorado / Termica e Fluidos / Doutor em Engenharia Mecânica

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Concerns surrounding the world’s current dependence on quickly depleting fossil fuels and their negative environmental impacts have brought about much research into renewable and sustainable energy sources. With population and economic growth not only is this dependence increasing but there is an increasing production of waste by society in general. With space becoming a premium commodity and environmental protection a necessity, landfilling of the majority of the world’s waste is no longer feasible. Thus, research is being carried out into waste-to-energy (WTE) processes and refuse derived fuels (RDF). This study focuses on thermochemical conversion, specifically pyrolysis of solid wastes as a means of energy product recovery. Before a specific waste stream can be used in WTE or RDF contexts its composition and degradation behaviour needs to be investigated. For this reason, a full physical characterisation of the municipal solid waste (MSW) from the Stellenbosch municipality was carried out. It was found that the composition of waste differs between areas within the municipality but the composition of the waste in general compares well with international data. It was found that six main components present in the recyclables stream; namely high and low density polyethylene (HD/LDPE), poly(ethylene terephthalate) (PET), glossy paper, office paper and newspaper would be suitable for thermochemical conversion. The thermal properties and pyrolytic degradation of these six components were investigated by multi heating rate thermogravimetric analysis (TGA) from which kinetic parameters (activation energy, pre-exponential factor and kinetic rate constants) were calculated by a differential isoconversional method. The volatiles released during degradation were identified by way of online mass spectrometry (TGA-MS) yielding six individual kinetic schemes. In order to gauge to what extent milligram pyrolytic experimentation (TGA-MS) can be used to predict larger scale pyrolytic behaviour, runs were performed on one plastic (HDPE) and one paper (glossy paper) sample on a gram scale pyrolytic plant under both slow and vacuum conditions. It was found that, especially for high thermal conductivity samples, yields on gram scale experimentation can be accurately predicted on a milligram scale. Further, the compositions of slow pyrolysis oils from glossy paper, obtained by gas chromatography–mass spectrometry (GC-MS), were compared to TGA-MS results as well as off gases captured from TGA runs by thermal desorption (TGA/TD-GC-MS). It was found that TGA-MS and TGA/TD-GC-MS can be used to predict the main functional groups in pyrolysis oil produced on a gram scale. Thus small scale experimentation can be used to determine the suitability of different waste components for pyrolytic conversion. / AFRIKAANSE OPSOMMING: Kommer oor die wêreld se huidige afhanklikheid van fossielbrandstowwe en die negatiewe uitwerking op die omgewing het baie navorsing oor hernubare en volhoubare energie bronne meegebring. Bevolking en ekonomiese groei veroorsaak 'n toename in hierdie afhanklikheid en in die produksie van afval deur die samelewing. Daar is baie min onbenutte grond oop en die beskerming van die omgewing het noodsaaklik geword. Dus is storting van die meeste van die wêreld se afval nie meer ‘n aanvaarbare opsie nie. As gevolg daarvan word daar tans navorsing in afval-tot-energie (ATE) prosesse en afval afgeleide brandstowwe (AAB) gedoen. Hierdie studie fokus op die termochemiese omskakeling van afval, spesifiek pirolise, as 'n methode vir energie-produk hernuwing. Voordat 'n spesifieke afvalstroom gebruik kan word as 'n AAB moet die samestelling en afbrekings gedrag eers ondersoek word. Daarom is 'n volledige fisiese karakterisering van die munisipale afval (MA) van Stellenbosch munisipaliteit uitgevoer. Resultate het getoon dat daar ‘n verskil in die samestelling van afval tussen die gebiede binne die munisipaliteit is. Afgesien daarvan vergelyk die samestelling van die afval in die algemeen goed met internasionale data. Daar is gevind dat daar ses belangrike komponente teenwoordig is in die herwinbare stroom wat geskik sou wees vir termochemiese omskakeling, naamlik; hoë en lae digtheid poliëtileen (HD/LDPE), poli(etileen tereftelaat) (PET), glans, kantoor en koerant papier. Die termiese eienskappe en termiese afbreking van hierdie ses komponente is ondersoek deur middel van multi-verhittimgs tempo termogravimetriese analise (TGA) waaruit kinetiese parameters (aktiveringsenergie, pre-eksponensiële faktor en kinetiese snelheidskonstantes) deur 'n differensiële omskakelings metode bereken is. Die vlugtige komponente wat tydens die afbreking vrygestel is, is geïdentifiseer deur aanlyn-massaspektrometrie (TGA-MS) wat ses individuele kinetiese skemas verskaf. Om vas te stel tot watter mate milligram pirolitiese eksperimente (TGA-MS) gebruik kan word om op ‘n groter skaal die pirolitiese gedrag te kan voorspel, is eksperimentele lopies op een plastiek- (HDPE) en een papier (glans papier) monster op 'n laboratorium skaal pirolise opstelling onder stadige- en vakuum omstandighede uitgevoer. Daar is gevind dat, veral met hoë hitte geleiding komponente, die opbrengs op gram skaal eksperimente akkuraat voorspel kan word op ‘n milligram skaal. Verder was die samestelling van die stadige pirolise olies uit glans papier, wat verkry word deur gaschromatografie-massaspektrometrie (GC-MS), vergelyk met TGA-MS resultate sowel as af-gasse gevang van TGA lopies deur termiese desorpsie (TGA/TD-GC –MS). Daar is gevind dat TGA-MS en TGA/TD-GC-MS gebruik kan word om die belangrikste funksionele groepe in pirolise olie, wat op 'n gram skaal geproduseer word, te voorspel. Dus kan milligram eksperimente gebruik word om die geskiktheid van afval komponente vir pirolitiese omskakeling te bepaal.

M.Tech. (Civil Engineering) / This study presents work on the design and construction of three dual-chamber microbial fuel cells (MFCs) using a sandwich separator electrode assembly (SSEA) and membrane cathode assembly (MCA) for the dual purposes of energy generation from domestic wastewater and wastewater treatment. MFC1 was designed using an improvised SSEA technique (i.e. a separator electrode membrane electrode configuration, SEMEC) by gluing a sandwich of anode, membrane and a mesh current collector cathode to an anode chamber made from a polyethylene wide-mouth bottle. The reactor was filled with 1500 mL of domestic wastewater and operated on a long fed-batch mode with a residence time of 3 weeks. The reactor was inoculated with a mixed culture of bacteria present in the wastewater stream. The aim was to study the impact of wastewater COD concentration on power generation and wastewater treatment efficiency. For MFC2 and MFC 3, cathodes were constructed using the MCA technique consisting of a membrane and a mesh current collector cathode, with the anode electrode at the opposite side of stacked Perspex sections used for the anode chamber. The impact of electrode material on current production was examined in this study. For MFC2 a mesh current collector treated with polytetrafluoroethylene (PTFE) and activated carbon (AC) functioned as the cathode, while the MFC3 cathode was an uncatalyzed mesh current collector. The two reactors were both filled with 350 mL of domestic wastewater...

Thesis (Ph. D.)--Utrecht University, 2007. / "This publication has been submitted as a Ph. D. thesis for the award of the degree of Doctor at Utrecht University, the Netherlands, 16 February 2007"--T.p. verso. Vita. Includes bibliographical references (p. 131-141).

Biogas has the potential to provide energy to communities, especially those where grid electrification will not be installed for a long time and who experience problems in accessing energy resources. The purpose of this study was to investigate whether biogas technology could provide households and a school with an acceptable, affordable, efficient, and sustainable alternative energy resource, thereby providing opportunities for cost savings, reduction of the labour burden and income generation. Three case studies were selected, two households and Myeka High School in rural Maphephetheni. Maphephetheni is situated approximately 80 km west of Durban and is characterised by the lack of grid electrification. The two households selected as case studies were both using firewood and paraffin for thermal energy. Collection of firewood was a tiresome burden to women and paraffin was expensive to purchase. The third case study, Myeka High School was using solar energy and LP gas to support its energy needs. Biogas digesters were donated to the two households and the school. Data before and after installation of biogas was collected through questionnaires, informal interviews and observations. Monitoring and evaluation of the case studies was carried out. Results collected revealed that biogas was an acceptable source of energy because the household and school equipped with the floating dome biogas digesters accepted cooking on biogas while the household used the fertiliser from biogas on their crops. However it was not affordable both to the household and the school because in the household income did not allow for its purchase while savings on energy expenditure from both the school and household could not offset the cost in the six years estimated by the engineer but it would take 11 years. Biogas was found to be efficient and sustainable provided proper management was available. Although income generation opportunities were not fully utilised, there was an opportunity for income generation through the biogas provided there was encouragement, support and markets available. Recommendations are that government policy should provide for training of stakeholders on proper management techniques. Government or organisations involved with biogas energy could do this, as well as provide an extension service for the dissemination of biogas and other renewable energy information. However, government policy should as in other countries provide for subsidies, risk underwritten bank loans or tax incentives to manufacturers. / Thesis (M.Soc.Sc.)-University of Natal, Pietermaritzburg, 2003.

Capes; CNPq / A geração de energia renovável desafia as empresas a envolver um processo em cadeia, no qual, todos os elos são corresponsáveis pela geração de novos produtos, processos, e pelo consumo e produção responsável, protegendo o meio ambiente e melhorando a vida das pessoas com que mantém interações. A presente pesquisa objetivou propor uma abordagem teórica do processo de geração de biometano a partir de resíduos agroindustriais. Para a realização da abordagem teórica, foi construído um Portfólio Bibliográfico e adotadas técnicas de revisões sistemáticas de literatura, para assegurar que estudos recentes e relevantes sobre o tema da pesquisa fossem capturados. A abordagem teórica foi dividida em três principais fases, sendo que a primeira fase do processo de geração de biometano incluiu a escolha, o pré-tratamento e o transporte do material orgânico até o biodigestor. A segunda fase do processo incluiu decisões como, a escolha do modelo do biodigestor e a utilização final do biofertilizante e do biogás gerado. Por fim, a terceira fase do processo de geração de biometano incluiu decisões como, a escolha da tecnologia a ser utilizada para o processo de purificação, e o uso final do biometano. O processo de geração de biometano a partir de resíduos agroindustriais, é um tema de poucas publicações no Brasil. O uso do biometano em países como Alemanha, Reino Unido e Suécia, está em um estágio consideravelmente avançado em relação a legislação e tecnologias, comparado ao Brasil. Desta forma, a proposta formulada neste estudo, auxilia acadêmicos, pesquisadores e gestores na área, na compreensão do processo como um todo e na tomada de decisões sustentáveis. / Renewable energy generation challenges companies to engage in a chain process in which all links are co-responsible for the generation of new products, processes and responsible consumption and production, protecting the environment and improving the lives of people with whom Interactions. The present research aimed to propose a theoretical approach of the biomethane generation process from agroindustrial waste. For the accomplishment of the theoretical approach, a Bibliographic Portfolio was constructed and techniques of systematic literature reviews were adopted to ensure that recent and relevant studies on the research topic were captured. The theoretical approach was divided into three main phases, and the first phase of the biomethane generation process included the selection, pretreatment and transport of the organic material to the biodigester. The second phase of the process included decisions such as the choice of biodigester model and the final use of biofertilizer and biogas generated. Finally, the third phase of the biomethane generation process included decisions such as the choice of technology to be used for the purification process and the final use of biomethane. The process of generating biomethane from agro-industrial waste is a subject of few publications in Brazil. The use of biomethane in countries such as Germany, the United Kingdom and Sweden is at a considerably advanced stage compared to legislation and technologies compared to Brazil. Thus, the proposal of this study assists academics, researchers and managers, in understanding the process as a whole and in making sustainable decisions.

Capes; CNPq / A geração de energia renovável desafia as empresas a envolver um processo em cadeia, no qual, todos os elos são corresponsáveis pela geração de novos produtos, processos, e pelo consumo e produção responsável, protegendo o meio ambiente e melhorando a vida das pessoas com que mantém interações. A presente pesquisa objetivou propor uma abordagem teórica do processo de geração de biometano a partir de resíduos agroindustriais. Para a realização da abordagem teórica, foi construído um Portfólio Bibliográfico e adotadas técnicas de revisões sistemáticas de literatura, para assegurar que estudos recentes e relevantes sobre o tema da pesquisa fossem capturados. A abordagem teórica foi dividida em três principais fases, sendo que a primeira fase do processo de geração de biometano incluiu a escolha, o pré-tratamento e o transporte do material orgânico até o biodigestor. A segunda fase do processo incluiu decisões como, a escolha do modelo do biodigestor e a utilização final do biofertilizante e do biogás gerado. Por fim, a terceira fase do processo de geração de biometano incluiu decisões como, a escolha da tecnologia a ser utilizada para o processo de purificação, e o uso final do biometano. O processo de geração de biometano a partir de resíduos agroindustriais, é um tema de poucas publicações no Brasil. O uso do biometano em países como Alemanha, Reino Unido e Suécia, está em um estágio consideravelmente avançado em relação a legislação e tecnologias, comparado ao Brasil. Desta forma, a proposta formulada neste estudo, auxilia acadêmicos, pesquisadores e gestores na área, na compreensão do processo como um todo e na tomada de decisões sustentáveis. / Renewable energy generation challenges companies to engage in a chain process in which all links are co-responsible for the generation of new products, processes and responsible consumption and production, protecting the environment and improving the lives of people with whom Interactions. The present research aimed to propose a theoretical approach of the biomethane generation process from agroindustrial waste. For the accomplishment of the theoretical approach, a Bibliographic Portfolio was constructed and techniques of systematic literature reviews were adopted to ensure that recent and relevant studies on the research topic were captured. The theoretical approach was divided into three main phases, and the first phase of the biomethane generation process included the selection, pretreatment and transport of the organic material to the biodigester. The second phase of the process included decisions such as the choice of biodigester model and the final use of biofertilizer and biogas generated. Finally, the third phase of the biomethane generation process included decisions such as the choice of technology to be used for the purification process and the final use of biomethane. The process of generating biomethane from agro-industrial waste is a subject of few publications in Brazil. The use of biomethane in countries such as Germany, the United Kingdom and Sweden is at a considerably advanced stage compared to legislation and technologies compared to Brazil. Thus, the proposal of this study assists academics, researchers and managers, in understanding the process as a whole and in making sustainable decisions.

At present, the use of other sources of energy other than energy source from crude oil has accelerated. This is due to limited resources of fossil fuel, increasing prices of crude oil and environmental concerns. Alternative fuels such as biofuel are becoming more important because it can serve as a replacement for petroleum diesel due to its comparable fuel properties and cleaner emission. For use in a standard diesel engine, biodiesel can be blended (mixed) with petroleum diesel at any concentration. In this study, transesterification of waste cooking oil with methanol was catalyzed by heterogeneous catalyst TiO2-supported-MgO and the biodiesel produced was characterised. Waste cooking oil (WCO) was used because it is regarded as one of the cheapest feedstock for biodiesel production in that most oils from oil crops are used as food. Waste cooking oil is available in vast amounts each day in every restaurants and fast food outlets worldwide. The waste cooking oil used in this study was laboratory prepared by the addition of 5 wt. % of oleic acid into 95 wt. % of soybeans oil.10 wt. % of titanium-supported-magnesium oxide catalyst (MgO/TiO2) used was prepared by incipient wetness impregnation and characterized using XRF, BET and XRD. These materials were tested with the catalyst for the conversion of waste vegetable oil to biodiesel in presence of methanol and hexane co-solvent. Methanol to oil mole ratio of 18:1 was employed in the transesterification process. When hexane was used as cosolvent, methanol to oil mole ratio of 18:1 and methanol to hexane mole ratio of 1:1 was used. The effects of reaction time, reaction temperature and hexane co-solvent on the waste vegetable oil conversion has been established. The 1HNMR analysis was used to estimate the structure of FAME produced. It was observed that the oil conversion increases with the increased reaction time, reaction temperature and use of hexane as co-solvent. / Chemical Engineering / M. Tech. (Chemical Engineering)

At present, the use of other sources of energy other than energy source from crude oil has accelerated. This is due to limited resources of fossil fuel, increasing prices of crude oil and environmental concerns. Alternative fuels such as biofuel are becoming more important because it can serve as a replacement for petroleum diesel due to its comparable fuel properties and cleaner emission. For use in a standard diesel engine, biodiesel can be blended (mixed) with petroleum diesel at any concentration. In this study, transesterification of waste cooking oil with methanol was catalyzed by heterogeneous catalyst TiO2-supported-MgO and the biodiesel produced was characterised. Waste cooking oil (WCO) was used because it is regarded as one of the cheapest feedstock for biodiesel production in that most oils from oil crops are used as food. Waste cooking oil is available in vast amounts each day in every restaurants and fast food outlets worldwide. The waste cooking oil used in this study was laboratory prepared by the addition of 5 wt. % of oleic acid into 95 wt. % of soybeans oil.10 wt. % of titanium-supported-magnesium oxide catalyst (MgO/TiO2) used was prepared by incipient wetness impregnation and characterized using XRF, BET and XRD. These materials were tested with the catalyst for the conversion of waste vegetable oil to biodiesel in presence of methanol and hexane co-solvent. Methanol to oil mole ratio of 18:1 was employed in the transesterification process. When hexane was used as cosolvent, methanol to oil mole ratio of 18:1 and methanol to hexane mole ratio of 1:1 was used. The effects of reaction time, reaction temperature and hexane co-solvent on the waste vegetable oil conversion has been established. The 1HNMR analysis was used to estimate the structure of FAME produced. It was observed that the oil conversion increases with the increased reaction time, reaction temperature and use of hexane as co-solvent. / Chemical Engineering / M. Tech. (Chemical Engineering)