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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.
491

Ação de enzimas de origem vegetal (Bromelina e Ficina) sobre anticorpos produzidos por cavalos imunizados com veneno de Bothrops jararaca / Vegetal enzyme action (Bromelain and Ficin) on antibodies produced by immunized horses with Bothrops pit viper venom.

Rodolfo Ferreira Marques 27 June 2016 (has links)
Enzimas proteolíticas de origem vegetal têm sido amplamente empregadas em diversos estudos devido a sua capacidade de clivar anticorpos em fragmentos específicos, o que, para algumas aplicações, pode ser mais interessante do que a molécula de imunoglobulina como um todo. Além disso, elas podem ser utilizadas diretamente no paciente no papel de um \"fármaco\" (Há exemplos da aplicação de enzimas no estudo de várias patologias como: doenças auto-imunes, traumáticas ou neurológicas), no auxílio de técnicas clínicas para a detecção de anticorpos e como ferramentas para a produção de soros. Apesar de a utilização dessas enzimas ter grande importância e extensa aplicabilidade, o modo de ação das proteases ainda não é bem compreendido, entretanto, as mesmas são de fácil acesso e largamente encontradas na natureza. A ficina (encontrada nas figueiras) e bromelina (proveniente do abacaxi) são, por exemplo, enzimas que vem sendo exploradas em diversos trabalhos e demostram capacidade de digerir anticorpos. Neste projeto, propusemos verificar a atividade destas enzimas sobre anticorpos provenientes de equinos produção de fragmentos imunorreativos de imunoglobulina a partir de proteases de origem vegetal, diminuindo o risco potencial de transmissão de doenças de origem animal. Espera-se que os fragmentos gerados possam contribuir para diversos estudos de ordem clínica e para a produção de soros adequados contra as toxinas presentes nos venenos de animais. As amostras de soro foram obtidas a partir da imunização dos cavalos pertencentes ao Instituto Butantan, com \"pool\" de veneno de serpente do gênero Bothrops. Esses anticorpos foram purificados utilizando ácido caprílico, digeridos por bromelina ou ficina e diafiltrados. Os resultados obtidos indicam a formação do fragmento de imunoglobulina F(ab)\'2, como proposto no projeto, entretanto necessitando ainda de um delineamento experimental mais amplo a fim de otimizar o processo de digestão atingindo uma maior quantidade de fragmentos F(ab)\'2. / Proteolytic enzymes from vegetal origin have been largely employed in several studies due to its capacity to cleave antibodies into specific fragments, which for some applications, could be more relevant than the immunoglobulin molecule itself. Beyond that, they could be used directley into a patient playing the role of a \"drug\" (There are examples of enzyme application in studies of several pathologies such as autoimmune, traumatic and neurological diseases), in the aid of clinical techniques for antibodies detection and as tools for serum production. Despite the fact that those enzymes have been of great importance and large applicability, its ease of access and ubiquity in nature, the protease mode of action is still not fully understood. Ficin (found in Fig trees) and Bromelain (found in pineapples) are, for example, enzymes that are being explored in an array of articles and demonstrate the capacity to digest antibodies. In this project, we propose to verify the activity of such enzymes from vegetal origins over the antibodies obtained from equines in the production of immunoreactive fragments of immunoglobulin, lowering the potential risk of animal origin diseases transmission. It is hoped that the fragments generated can contribute to studies of clinical level and the production of proper serum against toxins present in animal poisons. Plasma samples were obtained from horse immunization with a venon \"pool\" from Bothrops snakes at Instituto Butantan. These antibodies were purified using caprilic acid, digested by bromelain or ficin and purified again using chromatographic techniques. The results indicate the formation of an immunoglobulin fragment - F(ab)\'2, however, more experiments are needed to optimize the digestive process in order to improve the reaction yield.
492

Molecular physiology of digestion in arachnida: functional and comparative-evolutionary approaches. / Fisiologia molecular da digestão em Arachnida: abordagens funcional e comparativo-evolutiva.

Fuzita, Felipe Jun 30 May 2014 (has links)
Spiders and scorpions are efficient predators arachnid (PA) consuming preys larger than themselves. Few studies reported, molecularly, the digestion in PA. This work describes a biochemical, transcriptomic and proteomic analysis of the midgut and midgut glands (MMG) and digestive juice (DJ) from Nephilengys cruentata and Tityus serrulatus MMG. Cathepsin L, B, D and F, legumain, trypsin, astacin, carbohydrases and lipases were identified by these approaches. Peptide isomerase and ctenitoxins, which are venom proteins were identified, showing a correlation among digestive and venom enzymes. Summarily, PA relies in multi peptidase system mainly constituted of astacins for extracellular prey liquefaction and cathepsin L for intracellular digestion, describing a molecular model for digestion. Probably, during evolution, gene duplication led a diversification of astacins in the derived groups of Arachnida, like spiders, distinctly from what is observed in basal groups like scorpions. These data on Arachnida digestion will allow detailed multi disciplinary studies. / Aranhas e escorpiões são aracnídeos predadores eficientes (AP) consumindo presas maiores que eles mesmos. Poucos estudos descrevem molecularmente a digestão em AP. Neste trabalho caracterizamos bioquimicamente, por transcriptoma e proteoma o intestino e glândulas digestivas (IGD) e suco digestivo (SD) de Nephilengys cruentata e o IGD de Tityus serrulatus. Catepsinas L, B, D e F, legumaína, tripsinas, astacinas, carboidrases e lipases foram identificadas. Peptídeo isomerase e ctenitoxina foram identificadas no IGD. Estas proteínas podem indicar uma correlação entre enzimas digestivas e do veneno. Portanto, AP apresentam várias peptidases principalmente astacinas para liquefazer a presa extraoralmente e catepsinas L para digestão intracelular, descrevendo um modelo molecular para a digestão. Provavelmente, durante a evolução, eventos duplicação gênica levaram à diversificação das astacinas aracnídeos derivados, como as aranhas, diferentemente dos grupos basais, como os escorpiões. Estes dados sobre a digestão em Arachnida permitirão estudos multidisciplinares.
493

Biodigestão da fração orgânica de resíduos sólidos em um reator de duas fases operado em bateladas sequenciais com imobilização da biomassa. / Biodigestion of the organic fraction of solid wates in a two-phase reactor, operated in sequential batch with biomass immobilized.

Culi, Mario Jose Lucero 28 November 2018 (has links)
O presente trabalho avaliou a geração de biogás em um reator de duas fases, operado em bateladas sequencias, com resíduos coletados no CEAGESP de São Paulo-SP. O reator com volume efetivo de 10,7 L, era composto por um biofiltro anaeróbio em sua parte inferior, seguido por um separador de gases e posteriormente por um depósito de resíduos a digerir na parte superior. O inóculo era proveniente do fundo de uma lagoa de lixiviados do aterro de São Carlos-SP. O experimento foi conduzido em temperatura controlada em 30 ± 2 ºC nas Etapas 1, 2 e 3. A Etapa 1 consistiu na ativação e adaptação da biomassa, utilizando-se etanol e posteriormente resíduo orgânico do CEAGESP. A Etapa 2 consistiu na operação anaeróbia do sistema com resíduo do CEAGESP com lodo já adaptado. Na Etapa 3, verificou-se o efeito da aeração no compartimento de resíduos. Na Etapa 4, avaliou-se a influência da temperatura na digestão anaeróbia e com isto foi possível a obtenção do coeficiente de Arrhenius. Na Etapa 5, comparou-se o sistema de duas fases com um segundo reator anaeróbio, com configuração parecida com a convencional. Os resultados obtidos de todas as etapas na geração de biogás no reator de duas fases foram de 0,44; 0,44; 0,47 m3 /Kg SV e as eficiências de remoção de Sólidos Voláteis foram de 82,1%; 84,5% e 84,8% nas Etapa 1, 2 e 3, respetivamente, com um tempo de ração de 14 d nas três etapas. As concentrações de metano foram de 68,4; 67,1 e 66,6%, respectivamente. Na Etapa 4, os resultados da geração de biogás foram de 0,36; 0,38; 0,41; 0,41 m3 biogás/Kg SV nas temperaturas 25,6 ºC; 28,9 ºC; 34,0 ºC e 38,1 ºC, respetivamente. Denotando que a temperatura é um fator importante na geração de biogás em digestão anaeróbia. No reator convencional, a geração de biogás foi de 0,32 m3 biogás/Kg SV. / The present work evaluated the biogas generation in a two-phase reactor, operated in batch sequences, with residues collected at CEAGESP in São Paulo-SP. The reactor with an effective volume of 10.7 L was composed of an anaerobic biofilter in its lower part, followed by a gas separator and later by a deposit of waste to digest in the upper part. The inoculum was from the bottom of a leachate pond in the São Carlos-SP landfill. The experiment was conducted at a temperature of 30 ± 2 º C in Steps 1, 2 and 3. Step 1, consisted of the activation and adaptation of the biomass using ethanol and then organic waste from CEAGESP. Step 2, consisted of the anaerobic operation of the system with residue of the CEAGESP with already adapted sludge. In Step 3, the effect of aeration on the waste compartment was verified. In Step 4, the influence of temperature on the anaerobic digestion was evaluated and with this it was possible to obtain the Arrhenius coefficient. In Step 5, the two-phase system was compared with a second anaerobic reactor, with the same configuration as conventional. The results of all stages in the biogas generation in the two-phase reactor were 0.44; 0.44; 0.47 m3 / Kg SV and the removal efficiencies of Volatile Solids were 82.1%; 84.5% and 84.8% in Step 1, 2 and 3 respectively; and a feed time were of 14 d in the three steps. Consequently, the percentage of methane was 68.4; 67.1 and 66.6%. In stage 4 the results in the biogas generation were 0.36; 0.38; 0.41; 0.41 m3 biogas / Kg SV at temperatures 25.6 ° C; 28.9 ° C; 34.0 ° C and 38.1 ° C respectively. In the conventional reactor the biogas generation was 0.32 m3 biogas / Kg SV.
494

Digestibilidade in vitro e sua correlação com a resposta glicemica produzida por alimentos contendo amido / In vitro digestibility and its correlation with the glycemic response produced by starch-containing foods

Seravalli, Elisena Aparecida Guastaferro 30 January 1991 (has links)
Avaliando-se, em ratos a glicemia produzida pela ingestão de diferentes alimentos contendo carboidratos complexos e, através de ensaios \"in vitro\", observou-se que as sementes de leguminosas (feijão e lentilha) produziram menores respostas glicêmicas do que a dos cereais (arroz, pão, macarrão, farelo de trigo, polenta, farinha de milho e extrusado de milho) e dos tubérculos ( batata, mandioca, farinha de mandioca e beiju) (p<0,05). Observou-se, ainda correlação positiva entre as respostas \"in vivo\" e os ensaios de digestibilidde \"in vitro\" (r=0,95 p<0,0l). As causas das diferenças observadas não são ainda bem conhecidas. Nas análises \"in vitro\" com feijões que sofreram diferentes tratamentos e por observações ao microscópio óptico, verificou-se que com o aumento do tempo de cocção ocorreu descompactação celular, porém a parede celular que envolve os grânulos não sofreu ruptura. A resistência oferecida à desintegração parece ser um dos possíveis fatores responsáveis pela menor digestibilidade das sementes de leguminosas. / The determination of postprandial glycemia from ingest of different foods contained complex carbohydrates, \"in vivo\" and \"in vitro\" assays, showed that leguminous seeds (bean and lentil) produced lower glycemic responses than those from the cereals (rice, bread, macaroni, wheat bran, porridge corn, cornflakes and corn flour) and the tubercles (potato, cassava, cassava flour and \"beiju\") (p<0,05). positive relationship between the \"in vivo\" responses and the \"in vitro\" digestibility assays (r=0,95, p<0,0l) was observed. The causes of the observed differences werenot knomn yet. In the \"in vitro\" analysis, heat treatment and optical microscope with beans were applied. The results from optical microscope revealed that the longer the cooking time was the greater the cell separated. And no damages on bean cell walls were observed. The resistance of cell wall to heat damage could be one of possible factors for the lower digestibility of the leguminous seeds.
495

Microscale biomass generation for continuous power supply to remote customers

Loeser, Mathias January 2010 (has links)
Remotely located and sparsely populated areas often do not have access to an efficient grid connection for electricity supply. However, plenty of biomass is normally available in such areas. Instead of employing island solutions such as small diesel generators or large battery stacks for power provision, a flexibly operating microscale biomass power plant using locally available and renewable feedstock is not only an efficient way of providing those areas with competitive and reliable electricity, but also a step towards energy self sufficiency for a large share of areas worldwide, and towards mitigating the looming high costs of grid infrastructure upgrading and extension. A novel power plant design combining thermo chemical and biochemical biomass treatment was developed in this research. This system consists of a small scale gasifier and an anaerobic digester unit, both coupled to a gas storage system and a micro turbine as the generation unit. This design is suitable to continuously provide reliable electricity and accommodate fluctuating residential power demand, and it can be scaled to a level of around 100kWe, which is a fitting size for a group of residential customers, such as in a remote village. The project covers a review of available technology; the choice of suitable technology for such a plant and the design of the system; the set up of a detailed plant model in chemical engineering software; extensive simulation studies on the basis of load profiles to evaluate and optimise operation; and feedstock sourcing, efficiency and economic analyses. It will be shown that such a system is a feasible and economic solution for remote power supply, and that it can overcome many of the current obstacles of electrifying rural regions.
496

Biodigestão da fração orgânica de resíduos sólidos em um reator de duas fases operado em bateladas sequenciais com imobilização da biomassa. / Biodigestion of the organic fraction of solid wates in a two-phase reactor, operated in sequential batch with biomass immobilized.

Mario Jose Lucero Culi 28 November 2018 (has links)
O presente trabalho avaliou a geração de biogás em um reator de duas fases, operado em bateladas sequencias, com resíduos coletados no CEAGESP de São Paulo-SP. O reator com volume efetivo de 10,7 L, era composto por um biofiltro anaeróbio em sua parte inferior, seguido por um separador de gases e posteriormente por um depósito de resíduos a digerir na parte superior. O inóculo era proveniente do fundo de uma lagoa de lixiviados do aterro de São Carlos-SP. O experimento foi conduzido em temperatura controlada em 30 ± 2 ºC nas Etapas 1, 2 e 3. A Etapa 1 consistiu na ativação e adaptação da biomassa, utilizando-se etanol e posteriormente resíduo orgânico do CEAGESP. A Etapa 2 consistiu na operação anaeróbia do sistema com resíduo do CEAGESP com lodo já adaptado. Na Etapa 3, verificou-se o efeito da aeração no compartimento de resíduos. Na Etapa 4, avaliou-se a influência da temperatura na digestão anaeróbia e com isto foi possível a obtenção do coeficiente de Arrhenius. Na Etapa 5, comparou-se o sistema de duas fases com um segundo reator anaeróbio, com configuração parecida com a convencional. Os resultados obtidos de todas as etapas na geração de biogás no reator de duas fases foram de 0,44; 0,44; 0,47 m3 /Kg SV e as eficiências de remoção de Sólidos Voláteis foram de 82,1%; 84,5% e 84,8% nas Etapa 1, 2 e 3, respetivamente, com um tempo de ração de 14 d nas três etapas. As concentrações de metano foram de 68,4; 67,1 e 66,6%, respectivamente. Na Etapa 4, os resultados da geração de biogás foram de 0,36; 0,38; 0,41; 0,41 m3 biogás/Kg SV nas temperaturas 25,6 ºC; 28,9 ºC; 34,0 ºC e 38,1 ºC, respetivamente. Denotando que a temperatura é um fator importante na geração de biogás em digestão anaeróbia. No reator convencional, a geração de biogás foi de 0,32 m3 biogás/Kg SV. / The present work evaluated the biogas generation in a two-phase reactor, operated in batch sequences, with residues collected at CEAGESP in São Paulo-SP. The reactor with an effective volume of 10.7 L was composed of an anaerobic biofilter in its lower part, followed by a gas separator and later by a deposit of waste to digest in the upper part. The inoculum was from the bottom of a leachate pond in the São Carlos-SP landfill. The experiment was conducted at a temperature of 30 ± 2 º C in Steps 1, 2 and 3. Step 1, consisted of the activation and adaptation of the biomass using ethanol and then organic waste from CEAGESP. Step 2, consisted of the anaerobic operation of the system with residue of the CEAGESP with already adapted sludge. In Step 3, the effect of aeration on the waste compartment was verified. In Step 4, the influence of temperature on the anaerobic digestion was evaluated and with this it was possible to obtain the Arrhenius coefficient. In Step 5, the two-phase system was compared with a second anaerobic reactor, with the same configuration as conventional. The results of all stages in the biogas generation in the two-phase reactor were 0.44; 0.44; 0.47 m3 / Kg SV and the removal efficiencies of Volatile Solids were 82.1%; 84.5% and 84.8% in Step 1, 2 and 3 respectively; and a feed time were of 14 d in the three steps. Consequently, the percentage of methane was 68.4; 67.1 and 66.6%. In stage 4 the results in the biogas generation were 0.36; 0.38; 0.41; 0.41 m3 biogas / Kg SV at temperatures 25.6 ° C; 28.9 ° C; 34.0 ° C and 38.1 ° C respectively. In the conventional reactor the biogas generation was 0.32 m3 biogas / Kg SV.
497

Feeding and nutrition of tropical farmed fish and shrimp: pellet water stability, in vitro protein digestion, comparison of inert markers, evaluation of practical feeds, and dietary amino acid requirement / Alimentação e nutrição de peixes e camarões tropicais cultivados: estabilidade do pélete na água, digestão proteica in vitro, comparação de marcadores inertes, avaliação de rações práticas, e exigência de aminoácidos na dieta

Thiago Raggi 29 July 2016 (has links)
The aim of this thesis was to evaluate the feeding and nutrition of tropical farmed fish and shrimp, targeting its applicability to aquaculture farming. The study of the actual panorama of aquafeed quality for tilapia Oreochromis niloticus and shrimp Litopenaeus vannamei farmed in Brazil showed that the proximate compositions between the analyzed feeds were mostly consistent with the declared values from the manufacturers, however, the feed water stability showed the opposite; the in vitro pH-stat species-specific method to determine the protein degree of hydrolysis (DH) showed to be a useful tool to evaluate feed quality; and NIRS technique can be used in many applications throughout the aquafeed industry, being an efficient tool for rapidly assessing feed quality in terms of DH. A second study evaluated the acid-insoluble ash (AIA) and chromic oxide (Cr2O3) as inert markers and feed processing method (industrial extruded vs. laboratory cold pelleted) to determine apparent digestibility coefficient (ADC) of dry matter and crude protein of juvenile L. vannamei. The AIA showed to be an effective natural endogenous marker for digestibility trials with L. vanammei, however, for commercial feeds attention should be paid to feed AIA level; the extruded feed showed better animal performance than the cold pelleted feed, however, ADC of both feeds were not significantly different from each other. Further, two feeding trials were conducted with juvenile cobia Rachycentron canadum: (1) feeding trial conducted within floating net cages to test the nutritional efficacy of different dietary feeding regimes ranging from the use of trashfish, in-house formulated feeds, to dry commercial extruded marine fish feed; and (2) feeding trial conducted within indoor water-recirculated tanks to test the nutritional efficiency of different potential dietary fishmeal replacers within dry in-house prepared diets. Generally, fish performance was superior in the net-cage feeding trial compared with the indoor water-recirculated tank trial; overall, the fish growth and performance of the experimental diets were very similar, showing that the alternative ingredients could be included and replace part (50%) of the fishmeal component; the results from both trials concluded that the cobia requires practices diets with high levels of crude protein and lipid, and the inclusion of alternative plant-based and terrestrial animal protein sources was possible; the quantitative essential amino acid (EAA) requirement values estimated by the protein accretion method was highly correlated to the average of each of the EAA requirement for the species of carnivorous fish reported in the literature, and could be recommended for formulation of commercial feed for cobia R. canadum. Finally, a tentative to quantify the total sulfur amino acid requirement of juvenile Florida Pompano Trachinotus carolinus, was performed using combinations of various soybean protein products in order to develop cost-effective and environmentally-friendly diets. Although there was an apparent tendency in the results, the range of methionine levels employed in this study may not have been broad enough to accurately measure the dietary concentration necessary to estimate the total sulfur amino acid requirement; in addition, high variation results among the three replicates per diet did not provide sufficiency robustness for its estimation; this study within 45 days should not have been enough to show significant differences among the treatments. Long term feeding trials would be recommended from fingerling/juvenile to market size with full nutritional and economic evaluation of results. / O objetivo dessa tese foi avaliar a alimentação e nutrição de peixes e camarões tropicais cultivados, visando a sua aplicação à aquicultura. O estudo do atual panorama da qualidade das rações para tilapia e camarão cultivados no Brasil mostrou que a maioria das composições proximais das rações analisadas foram consistentes com os valores declarados pelos fabricantes, porém, a estabilidade das na água mostrou-se o oposto; o método in vitro pH-stat com enzimas espécie-específica, para determinação do grau de hidrólise da proteína (DH), mostrou ser uma ferramenta útil para avaliar a qualidade das rações; a técnica da espectrofotometria do infravermelho próximo (NIRS) pode ser usada em várias aplicações na indústria de alimentos aquáticos, sendo uma ferramenta eficiente para avaliar rapidamente a qualidade dos alimentos em termos de DH. Um segundo estudo avaliou a cinza insolúvel em ácido (AIA) e óxido de cromo (Cr2O3) como marcadores inertes, além de métodos de processamento de alimentos (extrusado industrial vs. peletizada a frio no laboratório) para determinar o coeficiente de digestibilidade aparente (ADC) da matéria seca e proteína bruta de juvenis de L. vannamei. O AIA mostrou ser um marcador endógeno natural eficaz para ensaios de digestibilidade com L. vanammei, no entanto, atenção especial deve ser dada aos níveis de AIA nas rações comerciais; a ração extrusada teve a melhor performance dos animais, porém, os valores de ADC entre as rações não foram diferentes significantemente. Além disso, dois experimentos de alimentação foram conduzidos com juvenis de beijupirá Rachycentron canadum: (1) experimento realizado em tanques-rede flutuantes para testar a eficácia nutricional de diferentes regimes alimentares, variando entre rejeito de pesca, rações preparadas em laboratório, e ração comercial extrusada; e (2) um experimento realizados em tanques com recirculação de água para testar a eficiência nutricional de diferentes potenciais substitutos de farinha de peixe, com dietas completadas preparadas em laboratório. Em geral, o desempenho dos peixes foi superior no experimento nos tanques-rede, comparado com o experimento nos tanques de recirculação de água; no geral o crescimento e performance dos peixes das dietas experimentais foram bem similares, concluindo que ingredientes alternativos podem ser incluídos e substituírem parte (50%) da farinha de peixe das rações; os resultados de ambos os estudos concluíram que o beijupirá requer dietas práticas com alto teores de proteína bruta e lipídeos, e a inclusão de fontes proteicas de origem vegetal e animal foi possível. Os valores quantitativos das exigências de amino acido essenciais (EAA) estimados pelo método de acreção de proteína na carcaça foram altamente correlacionados com as médias de exigência de cada EAA das as espécies de peixes carnívoros encontrados na literatura, e pode ser recomendado para a formulação de ração comercial para beijupirá R. canadum. Por ultimo, uma tentativa de quantificar as exigências de amino ácidos sulforosos totais para Florida Pompano Trachinotus carolinus, foi realizada utilizando combinações de vários ingredientes proteicos a base de soja, a fim de desenvolver dietas de baixo custo e ecologicamente sustentáveis. Embora houve uma tendência clara nos resultados, os intervalos dos níveis de metionina utilizados nesse estudo podem não ter sido amplos o suficiente para medir com precisão a concentração alimentar necessária para estimar a exigência dos de amino ácidos sulforosos totais; além disso, a alta variação entre as replicas não forneceu uma estimativa robusta; este estudo de 45 dias não deve ter sido suficiente para mostrar diferenças significativas entre os tratamentos.
498

Optimization of Pre-hydrolysis Conditions for the Production of Biogas

Awasume, Ignatius Ekwe, Sathiyaraj, Abel Prince Jabakumar January 2012 (has links)
Hydrolysis and solubilisation of organic material is known to be the rate limiting step during anaerobic digestion. In this study, the effect of pre-hydrolysis was investigated. The substrate had a composition of the following wastes streams: fish and slaughterhouse waste, cleaning waste, doggy meat, doggy sludge, doggy dry food, mink (fur), Norway slurry, SOR2-Industrial waste, and municipal solid waste (MSW) from households in Borås community.Analyses were made on two batches of experiments performed at two different mesophilic temperature conditions; 34 0C and 42 0C and with or without the addition of mesophilic sludge obtained from a waste water treatment plant. One of the substrate maintained the original carbon/nitrogen (C/N) ratio, and for the other substrate the carbon nitrogen ratio was then slightly increased by adding 7.98g of special shredded paper which contains 82% volatile solids (VS). The experiments were run for 7days with samples collected regularly after 0 day, 4 days, 5 days, 6 days and 7 days retention time. Chemical oxygen demand (COD), pH, total nitrogen, and volatile fatty acids (VFAs) as process indicators were analyzed.The results showed that at 42 0C the rate of hydrolysis was faster with a higher COD release and removal. The optimum retention time for hydrolysis was 4 days and any longer time caused some of the carbon to be lost to carbon dioxide. The effect of adding mesophilic sludge had no significant effect. An increased C/N ratio resulted in a balanced system with lower VFAs produced compared with that from the original substrate mixture. / <p>Acknowledgements: The authors are heartily thankful to their supervisor Ilona Sárvári Horváth whose guidance and support from the initial to the final level of this thesis work enabled us to gain a deeper understanding of the project.</p><p>We equally extend our sincere gratitude to the following persons who never ceased in helping until this work was complete.</p><p>Solmaz Aslanzadeh: For sharing her precious time and positive insight in coping with associated challenges of the project.</p><p>Hanson Jonas: Your assistance and patience over our laboratory experiments given the limited resources vis-a-vis students demand is quite reminding and saluted.</p><p>The support team at Sobacken Biogas plant: Your concern and timely assistance beginning from the supply of the substrate and the opportunity granted us to use your laboratory station greatly ensured results validation.</p><p>Program: MSc in Resource Recovery - Sustainable Engineering</p><p>Program: MSc in Resource Recovery - Industrial Biotechnology</p>
499

Continuous co-digestion of agro-industrial residues

Siripong, Chuthathip, Dulyakasem, Supusanee January 2012 (has links)
Slaughterhouse waste (SB) has high potential to be utilized in anaerobic digestion due to its high protein and lipid content. However, these are also the limiting factors of system stability. Thus, co-digestion of slaughterhouse waste with other agro-industrial residues (manure (M), various crops (VC) and municipal solid waste (MSW)) was introduced in this study to overcome this problem. The main objective of the work was to determine the operating parameters and the methane yield in semi-continuous co-digestion of slaughterhouse waste with other agro-industrial waste streams. Four continuously stirring tank reactors (CSTRs) with different substrates and mixtures (SB, SB:M, SB:VC and SB:VC:MSW) were started up operating with hydraulic retention time (HRT) of 25 days in thermophilic conditions. The highest organic loading rates which could be achieved were 0.9 g VS/L·d in digestion of SB and 1.5 g VS/L·d for the co-digestion mixtures. In these cases, average methane yields of 300, 510, 587 and 426 ml/g VS were obtained from the digestion of SB, and the co-digestion of SB:M, SB:VC and SB:VC: MSW, respectively, with methane contents in the biogas of 60-85%. The highest average methane yield of 587 ml/g VS was found in co-digestion of SB:VC, which was in accordance with the value of 592 ml/g VS detected during the batch digestion of the same mixture. Moreover, batch assays with different substrates as well as 11 different mixtures of those were also set up to investigate the methane potential and the effect of second feeding. The results showed that the co-digestion of SB:VC, SB:VC:MSW and SB:M could provide high methane potentials, where the highest methane yields of 592, 522 and 521 ml/g VS, respectively were obtained. Moreover, increasing, similar or decreasing methane yields were determined from the second feeding depending on the substrates and substrate mixtures used. / Program: MSc in Resource Recovery - Sustainable Engineering
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High rate biogas production from waste textiles

Rajendran, Karthik, Balasubramanian, Gopinath January 2011 (has links)
Textile is a global product used by all people in the world. These textiles after the use are thrown into the trash for incineration or land filling. However an efficient way that can be used to produce more energy, in an environmentally friendly process is anaerobic digestion. Waste textiles which contain cellulosic fibers (e.g. Cotton and viscose) can be converted to biogas. In this study, the performance of a two-stage anaerobic digestion process for biogas production from four different materials, including untreated jeans, treated jeans, cotton, and starch was studied. Starch was used as an easy-to-digest material to compare its digestion with that of cellulosic materials.The two-stage processes were composed of a CSTR (for hydrolysis) and a UASB (for methanogenisis) which were investigated in two different configurations, namely (closed and open systems). In the closed system, the outlet of UASB was completely returned back to the CSTR, while in the open system the UASB outlet was sent to sewage. In a stepwise progress, the OLR was aimed to increase from 2 to 20 g Vs per L per day along with reduction in hydraulic retention time from 10 days to 1 day.The results showed that the closed system was more stable when compared to the open system. The pre-treatment of jeans by NMMO helped to produce methane as that of cotton. The hydraulic retention time was decreased to less than 9 days for treated jeans and less than 5 days for starch. The overall methane yield at OLR of 4 gVS per L per day for starch and treated jeans was 98.5% and 97.4% in the closed system, whereas in the open system the yield was 77.0% and 35.5%, respectively.Another experiment was conducted to compare the performance of two-stage process with that of a single stage process of anaerobic digestion of textiles containing polyester and cotton or viscose. Viscose textiles produced more gas compared to the cotton textile; it may be due to the higher crystalline of cotton which makes it hard to be degraded by the microorganisms. Furthermore, two-stage process could able to produce more methane than the single stage process.The parameters like total solids, volatile solids, pH, gas production, gas composition, concentration of nutrients, and COD were also analyzed for both of the experiments.

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