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Kidby, David W. "Biogas hydrogen as an indicator of digester instability in anaerobic sewage sludge digesters". Thesis, University of Essex, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280473.
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Moço, Eunice Alexandra dos Santos. "Projeto de uma unidade produtora de biogás". Master's thesis, Instituto Politécnico de Tomar, 2012. http://hdl.handle.net/10400.26/5847.
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Começa-se a acreditar que a sociedade poderá colapsar, caso não se resolvam
alguns problemas de foro estrutural e de comportamento, em particular os problemas
associados à sustentabilidade, ou falta dela, dos recursos energéticos. Num momento em
que Portugal se encontra numa crise económica profunda, as alternativas que possam
reduzir a nossa dependência de combustíveis fósseis são cada vez mais determinantes para
o nosso futuro.
É verdade que as fontes de energia renovável estão a ganhar grande relevo,
particularmente em Portugal. Mas, as bioenergias estão ainda em segundo plano, face à
energia hídrica, solar e eólica. Entre as bioenergias, uma das formas com elevado
potencial, mas ainda pouco aproveitado é o biogás. O biogás é principalmente obtido de
resíduos (agropecuários, aterros sanitários, estações de tratamento de águas residuais): a
transformação desses resíduos através de digestão anaeróbia, representa uma forma atrativa
de os valorizar, e simultaneamente reduzir os impactos ambientais gerados pelo despejo
direto desses resíduos na natureza.
Neste projecto avaliou-se a possibilidade de implementar uma unidade de produção
de biogás, e da sua conversão em electricidade, a partir das lamas residuais do saneamento
da região de Cantanhade, nos casos em que estas não são convertidas em biogás nas
próprias ETAR da região.
Procederam-se aos balanços de massa e de energia, e ao dimensionamento dos
equipamentos principais, apesar de forma simplificada, para uma capacidade de digestão
de 600 toneladas por ano. Determinou-se que seria possível produzir cerca de 1200 MWh
de energia anualmente.
Porém, verificou.se que a capacidade é demasiado pequena para viabilizar
economicamente a instalação. Mas aumentando a capacidade para cerca do dobro, a
instalação já poderia ser viável num horizonte de 20 anos.
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Christodoulides, Jacqueline S. "Mixing in anaerobic digesters". Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.533276.
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Mons, Catherine. "Complications digestives chez les transplantés cardiaques". Bordeaux 2, 1996. http://www.theses.fr/1996BOR2M025.
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Velho, Douglas Ferreira. "Digestão anaeróbia de resíduos de restaurantes: partida do reator e avaliação do biofertilizante". Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5823.
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Comitesinos - Comitê de Gerenciamento da Bacia Hidrográfica do Rio dos Sinos
FUNDEPE - Fundação Universitária para Desenvolvimento do Ensino e da Pesquisa
Petrobras - Petróleo Brasileiro S. A.
UNISINOS - Universidade do Vale do Rio dos Sinos
O crescente aumento na geração de resíduos sólidos urbanos, somado às formas inadequadas de tratamento e disposição contribuem de forma direta e significativa com a problemática ambiental. Diante deste cenário, se faz necessário o desenvolvimento de alternativas que permitam outros benefícios além da disposição final apropriada. A digestão anaeróbia é uma alternativa viável e economicamente interessante para tratamento da fração orgânica dos resíduos sólidos urbanos. Considerando que em nosso país a fração orgânica é predominante nos resíduos sólidos urbanos, correspondendo em média a mais de 40% na composição, ao mesmo tempo que reduz o volume de resíduos enviados para os aterros sanitários, o processo gera produtos como o biogás e biofertilizante para uso agrícola. Esta pesquisa teve como objetivo avaliar a tratabilidade da fração orgânica dos resíduos sólidos domésticos provenientes do preparo e pós consumo das refeições de um restaurante universitário em um reator operado por batelada e qualificar as características do biofertilizante gerado. Para atingir este objetivo, a pesquisa foi realizada em três etapas, sendo que na etapa inicial foram realizadas quatro bateladas nas quais foram analisadas a proporção adequada de resíduos e inóculo para partida do reator sem que ocorresse acidificação. A segunda etapa consistiu na realização de seis bateladas, nas quais foram monitorados os principais parâmetros de operação e a terceira etapa onde foram avaliados os parâmetros químicos, físicos e microbiológicos do biofertilizante gerado ao final dos ensaios da segunda etapa. Os resultados da primeira etapa apontaram que a proporção de 6:1 em termos de sólidos totais voláteis, sendo lodo proveniente de um reator UASB e resíduos sólidos putrescíveis respectivamente, apresentaram uma partida adequada do sistema, sem que ocorresse acidificação, com o pH variando entre 6,9 e 7,7. Na segunda fase o monitoramento dos principais parâmetros de operação permitiu que no decorrer dos ensaios a proporção em termos de STV fosse reduzida, chegando a 1:1 de inóculo e substrato respectivamente, na batelada 10, portanto permitindo o tratamento de uma quantidade maior de resíduos em relação aos ensaios iniciais. Os resultados obtidos no monitoramento apontaram que o pH manteve-se dentro da faixa considerada ideal entre 6,0 e 8,0, porém o período de vinte e dois dias adotado como tempo de retenção mostrou-se insuficiente para degradação e consequente remoção da matéria orgânica, sendo que apenas a batelada 10 mostrou-se eficiente na remoção de STV 8,1% e carbono orgânico total 33,5%. A análise física do biofertilizante gerado no final de cada ensaio apontou umidade acima do permitido pela legislação, sendo indicado apenas para uso via aspersão. Quimicamente o biofertilizante apresentou insuficiência de nitrogênio, evidenciada nas elevadas relações C:N iniciais e finais obtidas e carência de macronutrientes como fósforo cujos resultados ficaram abaixo de 1%, mínimo imposto pela legislação e potássio, elemento que não foi detectado na pelo equipamento utilizado. A qualidade sanitária do composto atendeu a legislação quanto a presença de ovos viáveis de helmintos, sendo que todos os ensaios apresentaram resultados inferiores a uma unidade/4g, porém apresentou resultados acima do limite estabelecido para coliformes termotolerantes. O teste de germinação confirmou a ausência da fitotoxidade dos produtos.
The increase in the generation of municipal solid waste, together with the inadequate forms of treatment and disposal contribute directly and significantly to the environmental problems. In this scenario, it is necessary to develop alternatives to other benefits in addition to the appropriate disposal. Anaerobic digestion is a viable alternative and economically interesting for the treatment of the organic fraction of municipal solid waste. Whereas in our country the organic fraction is predominant in urban solid waste, corresponding to an average of over 40% in the composition, at the same time reducing the volume of waste sent to landfills, the process generates products such as biogas and biofertilizers for agricultural use. This research aimed to evaluate the treatability of the organic fraction of household waste from the preparation and after consumption of meals from a university restaurant in a reactor operated by batch and qualify the characteristics of the generated biofertilizers. To achieve this goal, the research was conducted in three phases, with the initial phase were held four batches were analyzed in which the proportions of the waste and inoculum for starting the reactor without acidification occurred. The second stage consisted of six batches, which were monitored in the main operating parameters and the third stage where we evaluated the chemical, physical and microbiological biofertilizer generated at the end of the second stage trials. The first step results indicated that the ratio of 6: 1 in terms of total volatile solids, and sludge from a UASB reactor and solid waste putrescible respectively, showed a suitable starting system without occur acidification to pH between 6.9 and 7.7. In the second stage, the monitoring of key operating parameters allowed during the experiment the proportion in terms STV be reduced, reaching 1: 1 inoculum and substrate respectively in the batch 10, thus allowing treatment of a larger quantity of waste compared to the initial test. The results showed that monitoring the pH was maintained within the range considered optimal between 6.0 and 8.0, but the period twenty-two days adopted as the retention time was insufficient to degradation and subsequent removal of matter organic, and only the batch 10 was effective in removing STV 8.1% and 33.5% total organic carbon. Physical analysis of biofertilizers generated at the end of each test pointed humidity above those permitted by law and is intended only for use via spraying. Chemically biofertilizer showed nitrogen deficiency, evidenced in the high ratios C: Initial N and obtained final and lack of nutrients such as phosphorus whose results were below 1% minimum required by the legislation and potassium, an element that was not detected in the equipment used. The sanitary quality of the compound met the legislation for the presence of viable helminth eggs, and all tests showed lower results to a unit / 4G, but showed results above the limit for fecal coliforms. The germination test confirmed the absence of phytotoxicity of products.
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Fukayama, Ellen Hatsumi [UNESP]. "Características quantitativas e qualitativas da cama de frango sob diferentes reutilizações: efeitos na produção de biogás e biofertilizante". Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/104913.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Objetivou-se avaliar o efeito da reutilização de cama de quatro lotes de criações de frangos de corte sobre a produção de cama de frango, a produção de biogás e a utilização do biofertilizante para adubação de milho. No capítulo sobre produção de cama foram avaliados quatro reutilizações de cama de frangos de corte criados em um galpão comercial dividido em 12 boxes pertencente à Empresa Rei Frango em São Carlos - SP - Brasil. Para caracterização da produção de cama foi avaliado a quantidade de cama produzida na matéria seca (MS) e o coeficiente de resíduo (Cr), ou seja, a quantidade de resíduo por kg de peso vivo das aves. Na caracterização qualitativa, foram analisados os teores de macro, micronutrientes e metais na casca de amendoim e cama de frango. Com o acréscimo de casca de amendoim nova mais o aumento de excretas do lote anterior, houve aumento (P<0,05) na produção de cama (MS). Assim, o Cr aumentou de acordo com a reutilização da cama. Porém, quando se avalia o Cr acumulado, ou seja, a quantidade de resíduo por kg de peso vivo acumulado das aves dos lotes criados, não houve diferença (P>0,05). De forma geral, foi observado que, com a reutilização da cama houve aumento (P<0,05) na concentração de nutrientes na cama. Conclui-se que com a reutilização de cama é possível igualar ou diminuir os custos com a aquisição de nova cama, aumentar a quantidade de nutrientes na cama para ser utilizada como biofertilizante na agricultura e estabilizar ou diminuir o impacto ambiental com a produção de cama por ave produzida. No capítulo sobre biodigestão anaeróbia de cama de frangos, para cada lote de aves conduzidos foram realizadas duas avaliações de biodigestão anaeróbia, sendo 4 ensaios (camas de 1 a 4º reutilização) avaliados de 2 formas: as 4 camas foram avaliadas em diferentes épocas do ano e também avaliadas na mesma época...
The objective was to evaluate the effect of reuse of litter of four broiler breeding cycle on the broiler litter’ production, the biogas’ production and use of organic fertilizer for fertilization of maize. In the chapter on production of litter were evaluated four reuses of litter of broiler chickens reared in a commercial shed divided in 12 boxes belonging to Rei Frango Company in São Carlos - São Paulo - Brazil. To characterize the production of litter was assessed the amount of litter produced in dry matter (DM) and the coefficient of waste (CW), or the amount of waste per kg of live birds. In qualitative characteristics, were analyzed the levels of macro, micro and metals in the shell of peanuts and broiler litter. With the addition of new peanut shell, plus the increase of manure of the previous batch, there was an increase (P<0.05) in the production of litter (dry matter - DM). Thus, the increased CW according to the reuse of litter. But when assessing the cumulative CW, or the amount of waste per kilogram of body weight of accumulated lots of birds created, there was no difference (P>0.05). Overall, it was observed that with the reuse of the litter there was an increase (P<0.05) in the concentration of nutrients in litter. It follows that with the reuse of litter can be equal or lower cost for the purchase of new litter, increase the amount of nutrients in litter to be used as organic fertilizer in agriculture and keep or reduce the environmental impact to the production of litter by produced per bird. In the chapter on anaerobic digester with litter of broiler, for each batch of birds conducted two evaluations were made of anaerobic digester, and 4 trials (litters from 1 to 4 reuse) evaluated in 2 ways: the 4 litters were evaluated at different times of the year and also evaluated in the same season, totaling 8 tests. 24 digesters were used in batch, distributed... (Complete abstract click electronic access below)
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Voegel, Célestine. "Impact BIochimique des effluents agricoles et agroindustriels sur les structures/ouvrages en BEtOn dans la filière de valorisation par Méthanisation (ou codigestion anaérobie)". Thesis, Toulouse, INPT, 2017. http://www.theses.fr/2017INPT0044/document.
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La digestion anaérobie est une succession d’étapes de dégradation de la matière organique, par l’intermédiaire de microorganismes, opérée industriellement dans des digesteurs en béton. Des métabolites microbiens (acides gras volatils (AGV), NH4+, CO2) produits au cours du processus de digestion attaquent la matrice cimentaire du béton. Afin d’assurer un développement pérenne de la filière de méthanisation, il est donc nécessaire de comprendre d’abord tous ces phénomènes d’altération pour ensuite proposer des solutions durables pour les matériaux de construction des digesteurs. Les objectifs de la thèse visaient à identifier et quantifier les agents agressifs pour le béton présents dans les milieux de la méthanisation, puis à comprendre leurs rôles dans les mécanismes d’altération des matrices cimentaires. Enfin, l’action de ces milieux a pu être comparée sur un panel de matériaux cimentaires réalisées à partir de différents liants : ciment Portland ordinaire, ciment de haut-fourneau, ciment d’aluminate de calcium et liant alcali activé. Dans des digesteurs de laboratoire, les concentrations maximales des agents chimiques agressifs mesurées pendant la digestion anaérobie d’un biodéchet modèle étaient de 3000 mg.L-1 d’AGV, de 800 mg.L-1 de NH4+, et de 140 mg.L-1 de CO2 dissous. La prolifération de microorganismes capables de métaboliser ces composés chimiques agressifs a été observée à la surface des matériaux cimentaires exposés dans le biodéchet au cours de sa digestion. La zone dégradée des matériaux cimentaires exposés est partiellement décalcifiée, vraisemblablement du fait de l’action des AGV et de l’ammonium NH4+, et carbonatée en raison de la présence de CO2 dissous. Des essais in situ, c’est à dire en conditions réelles, réalisées sur une plateforme expérimentale de méthanisation, ont permis de confirmer les phénomènes d’altération observés en laboratoire. En termes de durabilité, le ciment alumineux présente la meilleure résistance face aux attaques biochimiques lorsqu’on le compare au ciment ordinaire ou aux ciments composés de laitier de haut-fourneau au sein de systèmes de méthanisation en laboratoire ou in situAnaerobic digestion consists in the degradation of organic matter by the successive actions of microorganisms, industrially operated in digesters made of concrete. Microbial metabolites (volatile fatty acids (VFA), NH4+, CO2) produced during this process attack the cementitious matrix of the concrete. To ensure the development of this new industrial field, it appears essential to understand first the alteration phenomena, then to propose durable solutions for digesters’ construction materials. The thesis’ objectives were first to identify and to quantify the aggressive agents for concrete in anaerobic digestion media, then to understand their impacts on the cementitious materials’ alteration mechanisms. Finally, the impacts of those media were compared on different cement pastes made of : ordinary Portland cement, blast furnace slag cement, calcium aluminate cement or alkali activated materials. During laboratory tests, the maximal concentration in aggressive agents measured during the digestion of a synthetic biowaste were 3 000 mg.L-1 of VFA, 800 mg.L-1 of NH4+, and 140 mg.L-1 of dissolved CO2. The colonization of the microorganisms able to produce the aggressive agents has been observed on the cementitious materials’ surfaces exposed to the biowaste during digestion. The external degraded layers of the exposed cementitious materials are partially decalcified, most likely regarding to the action of the VFA and the NH4+. Carbonation has also been detected caused by the dissolved CO2. In situ experiments, in real conditions, achieved in an experimental anaerobic digestion platform, confirmed the alteration phenomena distinguished in the laboratory tests. In terms of durability, calcium aluminate cement present the best performances against the biochemical attacks compared to ordinary cement or blast furnace slag cement in laboratory or in situ anaerobic digestion systems
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Rieradevall, Joan. "Contaminació ramadera en zones rurals. Tractament anaerobi en purins de porc en digestors convencionals, i en planta pilot digestor-fossa a temperatura ambient". Doctoral thesis, Universitat Autònoma de Barcelona, 1992. http://hdl.handle.net/10803/3261.
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This work covers a study on livestock contamination in a rural municipality, the technological adaptation of the conventional anaerobic reactors for treating pig manure on farms for use on an industrial scales, and the preliminary experiences of a pilot digester pit at low temperature.The first phase of the study consisted of a global analysis a rural municipality dedicated preliminary to agricultural and livestock activities and having a typical production of waste matter. This study covered the population, the physical environment, the activities and the issue of livestock waste matter along with its impact on the environment.
Quantification and characterization of the livestock waste matter were affected as well as how its was being handled from storage to disposal.
Management and treatment actions for livestock waste matter have been proposed with a view to minimizing its impact on the environmental in rural areas.
Where livestock waste treatment are concerned, a study was carried out on the general features of the anaerobic digestion facilities in Catalonia (Spain), later making a follow up on four of them where pig manure is treated on an industrial scale.
The problems involved in the function of these facilities were studied, observing gas escapes from those under study plus degradation of the gasometers, obstructions in the pipes, the use of inadequate equipment and the inhibition of digestion.
The degree of purification at these facilities was assessed, with its being equal or inferior to fifty percent.
In the final stage of this study, research undertaken on anaerobic digestion at low temperature.
A study was made of the design and engineering of the pilot digester pit in terms cost, control of construction, the mechanisms to be installed, civil works, installation of gas and electricity and means of scientific control.
The start up of the digester pit was been assessed by applying a conventional inoculators, later observing the feasibility of this process.
Additional energy and thermographic studies of the facility were also made. A lower consumption of electricity than in conventional facilities was observed, as well as the fact of there being no thermal bridges in the digester pit.
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Pons, Laurent. "Troubles moteurs digestifs associés à une inflammation expérimentale du tractus digestif chez le rat. Rôle du PAF, des radicaux libres et des prostanoi͏̈des". Toulouse 3, 1993. http://www.theses.fr/1993TOU30146.
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Ce travail se proposait de decrire les troubles moteurs digestifs enregistres lors d'inflammations experimentales de l'intestin grele ou du colon chez le rat vigile, mais aussi d'en elucider les mecanismes par l'utilisation d'antagonistes ou d'inhibiteurs de la synthese endogene de divers mediateurs inflammatoires. Les phenomenes moteurs digestifs ont ete apprehendes par electromyographie a l'aide d'electrodes intraparietales implantees a demeure le long du tractus digestif ou par mesure de transit utilisant un marqueur radioactif. Dans une premiere serie d'experimentations, nous avons pu mettre en evidence la participation du paf dans les alterations du profil moteur intestinal observees apres l'administration d'endotoxines d'escherichia coli. Les effets des endotoxines seraient par ailleurs lies a une liberation de radicaux libres et de prostaglandines, eux-memes impliques dans les effets dependants du paf. La deuxieme partie de ce travail revele que le paf et les endotoxines d'escherichia coli presentent des effets similaires au niveau du colon: ils stimulent la motricite, accelerent le transit et augmentent l'humidite des feces. Les effets des endotoxines sur la motricite et le transit coliques sont en partie medies par le paf, mais aussi par les prostaglandines, alors que les effets secretoires tant des endotoxines comme ceux du paf dependraient d'une liberation de prostaglandines, et plus particulierement de prostaglandines de type e#2. La derniere partie de notre travail concerne les effets d'une inflammation du colon induite par l'administration d'acide trinitrobenzene sulfonique (tnb) et montre l'implication du leucotriene d#4 dans la genese des troubles precoces du transit colique. L'ensemble de ces resultats montre l'apparition de troubles moteurs digestifs associes a une inflammation et indique que ces manifestations sont la resultante d'une cascade d'evenements faisant intervenir differents mediateurs produits simultanement ou de facon successive
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Jansson, Johan. "Digester modelling for diagnostics and control". Doctoral thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-7547.
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This thesis will show the possibility for the development and use of an on-line model for application to continuous digesters for pulp production. The model is developed by using a program called Dymola (Dynamic Modeling Laboratory). What makes the Dymola software so well suited is that the program solves equations simultaneously. The model is a further development from the Purdue model [Bhartiya et al, 2003]. The main difference between this model and the Purdue model however, is the dynamics in the model. The dynamics are very important when you use the model for control purposes because the cooking process has long dead and retention times. The main purpose of this model is to use it for the advanced control of continuous digesters as well as giving the operators a better understanding of what happens in the cooking process when changes are made. The model will also be used for diagnostic purposes. Advanced control in this case is Model Predicted Control (MPC). The MPC will control the quality of the pulp “kappa” number and the chemical consumption during digestion. This thesis describes the model and results are shown for applications of on-line diagnosis in three pulp mills in South Africa. Real time process data from the pulp mills is fed into the model and a simulation is performed. Thereafter, the results from the simulation are compared to the actual measured data for a number of key variables. By comparing the simulation results to the real process data and following the trends of the deviations between the two, different types of faults and upsets can be detected in both the process and sensors.KKS project:Use of physical models combined with statistical models for improved digester control
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Armelin, Isabelle. "Manifestations digestives du purpura rhumatoïde chez l'enfant". Montpellier 1, 1990. http://www.theses.fr/1990MON11011.
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Auduval, Sandrine. "Les candidoses digestives". Bordeaux 2, 1996. http://www.theses.fr/1996BOR2P105.
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Kearney, Theresa Elizabeth. "Survival of pathogenic bacteria in anaerobic digesters". Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334706.
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Ishaq, Farryad. "Trace metal supplementation in wastewater sludge digesters". Thesis, University of Birmingham, 2012. http://etheses.bham.ac.uk//id/eprint/3896/.
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Multiple studies have shown the importance of transition metals for the microorganisms involved in anaerobic digestion. Deficiencies in metals can translate into suboptimal digester performances and therefore where present an opportunity to stimulate anaerobic digestion exists. Previous supplementation studies that have used EDTA complexed metals have shown conflicting results. Assays supplemented with cobalt-EDTA on its own consistently responded to a level equal to or higher than that from assays supplemented with a combination of metals. The results seemingly indicate that cobalt was the most commonly deficient metal in the sludge digesters. However this study has raised questions about the bioavailability of other metals as EDTA chelates, particularly nickel-EDTA. Differing levels of bioavailability for different EDTA complex metals explain how conflicting results for EDTA complexed metals can exist. Metal deficiencies were present 69% of the time in the wastewater sludge digesters samples. Given the questions raised about the bioavailability of metal-EDTA chelates the prevalence of deficiencies was likely to have been higher. At a site specific level it was found that a lower than expected Vmax for a given sites acetoclastic methanogen population corresponded with a positive response from supplementation and therefore it can act as an indicator of metal requirement.
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Zahr, Meia. "Separation of Tryptic Digested IgG with HPLC". Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233869.
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The antibody immunoglobulin G (IgG) can be tryptically digested into smaller peptides. This study attempted to develop a separation method for those peptides using RP-HPLC with a C18 column at room temperature. Optimizing separation of trypsin cleaved cytochrome C was used as a guideline before analyzing IgG. The optimized analysis of Cytochrome C was performed at wavelength 280nm (UV) and methanol was used as an organic solvent in mobile phase (B). A fast gradient to 100% mobile phase B with low flow rate gave favorable results for cytochrome C. A slow gradient to 100% mobile phase B was suited for IgG separation. The optimized gradient elution of cytochrome C and IgG was performed at 0.3 and 0.8 ml/min, respectively.Antikroppen Immunoglobulin G (IgG) kan klyvas till peptider med enzymet trypsin. Under denna studie ska utvecklades en separationsmetod för dessa peptider med RP-HPLC. Separationen utfördes med en C18 kolonn i rumstemperatur. Först optimerades en separation av trypsin-klyvt cytokrom C vars optimerade parametrar sedan användes som grund för IgG-separation. Optimeringen utfördes vid våglängden 280 nm(UV) och metanol användes som organiskt lösningsmedel i mobil fas (B). En snabb gradient upp till 100% B med låg flödeshastighet gav mest gynnsamt resultat för cytokrom C. Separationen av IgG gynnades av ett högt flöde och en långsam gradient till 100% B. Den optimerade gradientelueringen för cytokrom C och IgG gjordes vid flödet 0.3 respektive 0.8 ml/min.
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Fukayama, Ellen Hatsumi. "Características quantitativas e qualitativas da cama de frango sob diferentes reutilizações : efeitos na produção de biogás e biofertilizante /". Jaboticabal : [s.n.], 2008. http://hdl.handle.net/11449/104913.
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Orientador: Jorge de Lucas JuniorBanca: Roberto Alves de Oliveira
Banca: Júlio Cesar Pascale Palhares
Banca: Nilva Kazue Sakomura
Banca: Mônica Sarolli Silva de Mendonça Costa
Resumo: Objetivou-se avaliar o efeito da reutilização de cama de quatro lotes de criações de frangos de corte sobre a produção de cama de frango, a produção de biogás e a utilização do biofertilizante para adubação de milho. No capítulo sobre produção de cama foram avaliados quatro reutilizações de cama de frangos de corte criados em um galpão comercial dividido em 12 boxes pertencente à Empresa Rei Frango em São Carlos - SP - Brasil. Para caracterização da produção de cama foi avaliado a quantidade de cama produzida na matéria seca (MS) e o coeficiente de resíduo (Cr), ou seja, a quantidade de resíduo por kg de peso vivo das aves. Na caracterização qualitativa, foram analisados os teores de macro, micronutrientes e metais na casca de amendoim e cama de frango. Com o acréscimo de casca de amendoim nova mais o aumento de excretas do lote anterior, houve aumento (P<0,05) na produção de cama (MS). Assim, o Cr aumentou de acordo com a reutilização da cama. Porém, quando se avalia o Cr acumulado, ou seja, a quantidade de resíduo por kg de peso vivo acumulado das aves dos lotes criados, não houve diferença (P>0,05). De forma geral, foi observado que, com a reutilização da cama houve aumento (P<0,05) na concentração de nutrientes na cama. Conclui-se que com a reutilização de cama é possível igualar ou diminuir os custos com a aquisição de nova cama, aumentar a quantidade de nutrientes na cama para ser utilizada como biofertilizante na agricultura e estabilizar ou diminuir o impacto ambiental com a produção de cama por ave produzida. No capítulo sobre biodigestão anaeróbia de cama de frangos, para cada lote de aves conduzidos foram realizadas duas avaliações de biodigestão anaeróbia, sendo 4 ensaios (camas de 1 a 4º reutilização) avaliados de 2 formas: as 4 camas foram avaliadas em diferentes épocas do ano e também avaliadas na mesma época... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The objective was to evaluate the effect of reuse of litter of four broiler breeding cycle on the broiler litter' production, the biogas' production and use of organic fertilizer for fertilization of maize. In the chapter on production of litter were evaluated four reuses of litter of broiler chickens reared in a commercial shed divided in 12 boxes belonging to Rei Frango Company in São Carlos - São Paulo - Brazil. To characterize the production of litter was assessed the amount of litter produced in dry matter (DM) and the coefficient of waste (CW), or the amount of waste per kg of live birds. In qualitative characteristics, were analyzed the levels of macro, micro and metals in the shell of peanuts and broiler litter. With the addition of new peanut shell, plus the increase of manure of the previous batch, there was an increase (P<0.05) in the production of litter (dry matter - DM). Thus, the increased CW according to the reuse of litter. But when assessing the cumulative CW, or the amount of waste per kilogram of body weight of accumulated lots of birds created, there was no difference (P>0.05). Overall, it was observed that with the reuse of the litter there was an increase (P<0.05) in the concentration of nutrients in litter. It follows that with the reuse of litter can be equal or lower cost for the purchase of new litter, increase the amount of nutrients in litter to be used as organic fertilizer in agriculture and keep or reduce the environmental impact to the production of litter by produced per bird. In the chapter on anaerobic digester with litter of broiler, for each batch of birds conducted two evaluations were made of anaerobic digester, and 4 trials (litters from 1 to 4 reuse) evaluated in 2 ways: the 4 litters were evaluated at different times of the year and also evaluated in the same season, totaling 8 tests. 24 digesters were used in batch, distributed... (Complete abstract click electronic access below)
Doutor
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Onderková, Petra. "Zhodnocení ekologických rizik plynoucích z realizace a provozu bioplynových stanic". Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-259183.
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Environmental pollution, natural resources consumption and global climate change have been threats for mankind since 21 century. In order to antedate environmental pollution in many countries of the world including The Czech Republic we use legislative tool as a process of influence of the environment EIA. Substitution of non-renewable energy sources for renewable ones may retard global climate change markedly.
This thesis deals with analysis of specific biogas plants located in Moravian-Silesian region in relation to the environment and population.
It means that it deals with biomass utilization as a renewable source of energy. Within EIA process, it assesses the unity rate between prediction, said
in documentation, and the real state after implementation. As far as the population perspective is concerned, poeple assess great strength, weaknesses, opportunities
and threats.
Results of the research showed different perceptions of biogas before and after project implementation. The risk of discomfort housing (smell, increased traffic congestion, noise) threatens residents in older facilities where an EIA was not yet part of the legislation. The results also showed compliance with the information provided in the EIA documentation in relation to the population and the environment, and the state after realizing the plan of a biogas plant.
The thesis brings us new information within post-project analysis, it shows us the importance of EIA process and publicity involvement into this process. Defining the specific effects of biogas plants by mutual cooperation between the investor
and the public authorities can be achieved some functioning device with regard
to population and environmental components.
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Gamelin, Erick. "Pharmacologie clinique du 5-fluorouracile et de certains sels de platine chez des patients souffrant de cancers du tractus digestif et des voies aéro-digestives supérieures". Bordeaux 2, 1997. http://www.theses.fr/1997BOR28484.
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Bendezú, García Rogger Álvaro. "Mecanismo de producción de los síntomas digestivos funcionales". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/399830.
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En esta tesis se abordan los mecanismos que producen los síntomas digestivos funcionales haciendo uso de técnicas no invasivas como son la tomografía computarizada y la resonancia magnética nuclear. Para el análisis de las imágenes y estudio de su contenido se han diseñado softwares especiales en nuestro laboratorio.
En el primer estudio, empleando una metodología original y técnicas de inteligencia artificial se ha estudiado una cohorte grande de sujetos sanos para establecer el patrón de normalidad en la distribución de gas dentro del tubo digestivo. Además se incluyeron 88 enfermos con síntomas atribuidos al gas intestinal, a quienes se les estudió en situación basal y durante un episodio de distensión máxima. Los volúmenes medidos cuando el paciente se encontraba asintomático fueron similares a los de la cohorte de voluntarios sanos, sin embargo durante los episodios sintomáticos algunos pacientes presentaron un patrón de gas en el tubo digestivo fuera del rango de la normalidad.
En el segundo estudio se midió el componente no gaseoso a nivel del colon tanto en sujetos sanos como en enfermos con distensión abdominal, observándose que el contenido sólido presenta una distribución uniforme con variaciones en relación a la ingesta. Los síntomas abdominales funcionales no se relacionan con variaciones del contenido no gaseoso del colon.
En el tercer estudio, haciendo uso de imágenes abdominales obtenidas por resonancia magnética nuclear, se obtuvo una valoración fiable del colon y su contenido. Es así que el contenido no gaseoso presenta variaciones circadianas con un recambio sustancial producidas por la ingesta y la defecación. La ingesta de residuos no absorbibles en la dieta tiene una influencia marcada sobre el contenido no gaseoso del colon.In this thesis we have studied the mechanisms that produce functional gastrointestinal symptoms using non-invasive techniques such as computed tomography and magnetic resonance imaging. For image analysis and study of its contents we created special softwares in our laboratory. In the first study, using an original methodology and techniques of artificial intelligence we have studied a large cohort of healthy subjects to establish the pattern of normality in the distribution of gas within the digestive tract. In addition, 88 patients with symptoms attributed to intestinal gas were studied at baseline and during an episode of maximum distension. Volumes measured when the patient was asymptomatic were similar to those of the cohort of healthy volunteers, however during symptomatic episodes some patients had a pattern of gas in the digestive tract outside the range of normal. In the second study the non-gaseous component in the colon in both healthy subjects and in patients with abdominal distention was measured, showing that the solid content has a uniform distribution with variations related to ingestion of meals. Functional abdominal symptoms not related to changes in non-gaseous contents of the colon. In the third study, using abdominal images obtained by nuclear magnetic resonance, a reliable assessment of the colon and its contents was obtained. Thus the non-gaseous content presents circadian variations with substantial parts produced by ingestion and defecation. Intake nonabsorbable residues in the diet has a marked influence on colon nongaseous content.
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Boruchowicz, Arnaud. "Sarcoidose et tube digestif". Lille 2, 1993. http://www.theses.fr/1993LIL2M136.
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Rougelin-Clapasson, Christine. "Vascularites et tube digestif". Montpellier 1, 1990. http://www.theses.fr/1990MON11291.
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Cunha, Joaquim Miguel Gonçalves. "Digestão anaeróbia de biorresíduos". Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/23337.
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Mestrado em Engenharia do AmbienteA digestão anaeróbia (DA) é um processo com grande interesse no âmbito da gestão de resíduos pois para além de tratar estes resíduos diminuindo a carga poluente ao nível das emissões gasosas e dos efluentes líquido quando são descarregados no ambiente, permitem ainda recuperar os nutrientes para aplicação no solo como fertilizante e condicionador do solo, produzindo ainda biogás, que é uma fonte de energia renovável. A digestão anaeróbia é realizada por determinados microrganismos específicos, que, atuando na ausência de oxigénio, promovem a degradação da matéria orgânica, produzindo digestato e uma mistura gasosa composta por metano e dióxido de carbono. O presente trabalho tem como objetivo contribuir para o estudo do processo de digestão anaeróbia aplicado a biorresíduos de origem alimentar, no contexto da avaliação da operacionalidade de uma instalação piloto de digestão anaeróbia disponível no DAOUA. Para o efeito foram realizadas várias séries de ensaios, cada uma das quais em diferentes situações, na tentativa de obter condições de operação satisfatórias em estado estacionário, nomeadamente em relação à temperatura, ao pH, à produção de biogás, à carga orgânica/teor de sólidos e mistura. Em relação aos resultados obtidos, foi possível concluir que a condição inicial afeta de forma decisiva o desempenho do processo ao longo do tempo, nomeadamente a atividade da população bacteriana responsável pela metanogénese. Dos quatro ensaios reportados, apenas o último, realizado à temperatura de cerca de 25ºC, evidenciou as condições de estacionaridade desejadas: cerca de 125 litros de biogás por kg de biorresíduos contendo 50- 60% de CH4, na presença de um digestato com pH de cerca de 7,1, com teor de sólidos totais de 8-10%, alcalinidade de 5-6 gCaCO3.L-1, quase sem cheiro e facilmente centrifugável, contendo cerca 2-3% de azoto Kjeldahl referido ao digestato seco. Com as alterações introduzidas, a instalação evidenciou condições para a realização de estudos e lecionação à escala piloto, nomeadamente no âmbito do tratamento de biorresíduos por digestão anaeróbia, embora seja conveniente/necessário melhorar tecnicamente alguns dos dispositivos que apresenta atualmente ao nível de: alimentação, recolha/descarga do digestato, agitação/mistura, monitorização e registo de dados.
Anaerobic digestion (AD) is a process with great interest in the management of organic wastes because, in addition to treating this residue reducing the pollutant load at the level of the gaseous emissions and the liquid effluents when they are discharged into the environment, it also allows to recover the nutrients for application in soil as fertilizer/soil amendment and still produces biogas, which is a source of renewable energy. Anaerobic digestion is performed by certain specific microorganisms, which degrade organic matter in the absence of oxygen, producing a digestate and a gaseous mixture of methane and carbon dioxide. The present work aims to contribute to the study of the anaerobic digestion applied to biowaste, in the context of the evaluation of the operational conditions of a pilot plant available in DAOUA. For this purpose, several series of tests, each in different situations, were carried out to obtain satisfactory steady state operating conditions, namely in order to temperature, pH, biogas production, organic load and mixing. In relation to the obtained results, it was possible to conclude that the initial condition affects in a decisive way the performance of the process over time, namely the activity of the bacterial population responsible for methanogenesis. Of the four trials reported, only the last one, performed at a temperature of about 25ºC, showed the desired stationarity conditions: about 125 liters of biogas per kg of biowaste containing 50-60% CH4, in the presence of digestate with pH of about 7,1, with total solids content of 8-10%, alkalinity of 5-6 gCaCO3.L-1, almost odorless and easily centrifugable, containing about 2-3% of Kjeldahl nitrogen referred to the dry digestate. With the changes introduced, the installation showed conditions for carrying out studies and lecturing at the pilot scale, namely in the treatment of biowaste by anaerobic digestion, although it is convenient/necessary to technically to improve some of its devices: feeder, outlet digestate port, continuous mixer, monitoring and recording data.
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Pech-Gourg, Laurent. "Troubles digestifs et sports". Montpellier 1, 1992. http://www.theses.fr/1992MON11211.
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GRUNER, LAURENT. "Les hemorragies digestives basses". Lyon 1, 1990. http://www.theses.fr/1990LYO1M373.
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Stephenson, Robert John. "A comparison of retained biomass anaerobic digester designs". Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26740.
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The principles behind anaerobic digestion are fairly well understood, but the limits of application of each digester design are not known. Because there are significant differences in the properties of the many wastewaters requiring treatment optimal anaerobic digester performance requires the matching of feed characteristics to a digester design and mode of operation. No consensus has yet emerged on digester design, operating conditions or feed/digester match-ups.
In this study, three bench scale retained biomass anaerobic digester designs were examined for their response to a sequence of varied hydraulic retention times (HRTs) and influent wastewater concentrations. The digester designs studied were the upflow anaerobic filter, the upflow anaerobic expanded bed and the upflow anaerobic sludge bed. The wastewater was screened and diluted dairy cow manure obtained from the UBC dairy barn. The parameters monitored included the total and soluble chemical oxygen demand (TCOD and SCOD), volatile and suspended solids (VS and SS), total volatile fatty acids (VFAs), total Kjeldahl and ammonia nitrogen (TKN and NH₃-N), pH, biogas production, and the methane (CH₄) and carbon dioxide (C0₂) content of the biogas.
Wastewater treatment efficiencies, measured in terms of TCOD, SCOD, VS, and TVFA removals, and methane productivity and methane yield for each of the digester designs were examined for the range of the operating conditions.
The anaerobic filter digester effected a mean TCOD removal efficiency of 47% ± 14% at a mean 4.0 day HRT, 51% ± 9% at a mean 2.3 day HRT and 35% ± 11% at a mean 1.3 day HRT. The expanded bed digester effected a mean TCOD removal of 45% ± 15% at a mean 4.3 day HRT, 38% ± 12% at a mean 2.5 day HRT and 28% ± 9% at a mean 1.3 day HRT. The sludge bed digester effected a mean TCOD removal of 53% ± 9% at a mean 3.8 day HRT, 45% ± 12% at a mean 2.2 day HRT and 32% ± 10% at a mean 1.2 day HRT. For all three digesters, the difference in the treatment efficiency over the range of HRTs tested, from 5 to 1.25 days was not in proportion to the change in HRT. Methane productivity, measured against either the removal or addition of substrate in terms of TCOD, SCOD, VS and TVFA, demonstrated considerable variability. Methane production increased with both substrate addition and substrate removal. Methane yield increased with increasing HRT. The sludge bed digester generally exhibited the greatest but most variable methane yields. It produced 0.095 L CH₄/g VS added at a mean 3.8 day HRT and 0.037 L CH₄/g VS added at a mean 1.2 day HRT. The anaerobic filter delivered the greatest methane yield at the intermediate HRT, 0.044 L CH₄/g VS added at a mean 2.3 day HRT. The expanded bed demonstrated low methane yields over the range of feed strengths and HRTs tested.
Biogas composition averaged 62.1% methane and 17.1% carbon dioxide for the anaerobic filter, 43.6% methane and 5.3% carbon dioxide for the expanded bed. and 61.1% methane and 18.9% carbon dioxide for the sludge bed.Applied Science, Faculty of
Graduate
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Campbell, Alison June. "The behaviour of pharmaceuticals in anaerobic digester sludge". Thesis, University of Portsmouth, 2013. https://researchportal.port.ac.uk/portal/en/theses/the-behaviour-of-pharmaceuticals-in-anaerobic-digester-sludge(995bec06-33fd-4c74-96a3-db4aba5a1c30).html.
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Pharmaceuticals are biologically active compounds that may be consumed in hundreds of tonnes per year, and which are excreted into municipal sewerage systems. Many pharmaceuticals persist during sewage treatment, and significant environmental risk has been linked to incomplete removal of pharmaceuticals. Evaluation of this risk is important and should be as representative as possible, taking into consideration all significant exposure routes and removal processes. Sludge treatment processes are of particular interest because they offer a final opportunity for the removal of persistent compounds before the disposal of treated biosolids. During environmental risk assessment, it is currently assumed that anaerobic sludge treatment results in insignificant removal of persistent and adsorptive compounds from sewage sludge. This project was undertaken to address whether this assumption is valid. This thesis describes research into the behaviour and fate of pharmaceuticals in anaerobic digester sludge, and examines how redox conditions influence removal efficiency. Nine commonly used pharmaceuticals (caffeine, cimetidine, fluoxetine, ibuprofen, metformin, naproxen, paroxetine, propranolol and salicylic acid) were selected for use based upon detection levels within sewage sludge and predicted anaerobic biodegradability. Initial experiments were conducted to identify toxicity to anaerobic microorganisms and anaerobic biodegradability. No toxicity to the microorganisms in anaerobic sludge was identified at ≤ 50 mg C L-1for any of the selected pharmaceuticals. The extent of removal in anaerobic sludge and the principal removal mechanism was found to vary between the selected pharmaceuticals. Metformin and salicylic acid were removed by 82 and 93% through mineralisation, respectively; naproxen was completely removed through primary biodegradation; fluoxetine, paroxetine and propranolol were removed by 92 and 96 and 55% due to adsorption, respectively. It was hypothesised that the removal of pharmaceuticals in anaerobic sludge through biodegradation and adsorption would be observed at varying rates under differing redox conditions. Test systems using headspace gas flushing and chemical amendment were evaluated for the control of redox conditions, with Eh measurements and DOC removal being used to indicate the stability of the system and its capacity for biodegradation. The addition of nitrate, sulfate and carbonate resulted in poised Eh values in the region of +200, -200 and -200 mV, respectively and 81, 78 and 74% removal of DOC, respectively. This methodology was subsequently used to evaluate the removal of naproxen, propranolol and fluoxetine under carbonate-, nitrate- and sulfate-amended conditions. Significant differences (p = 0.001) in the removal of naproxen through primary biodegradation were found to exist between different redox conditions. Naproxen was completely removed under control conditions, while 26, 98 and 61% removal was observed under nitrate- sulfate- and carbonate amended conditions, respectively. Some differences were observed in Kd values, however, redox amendment was found to have little influence upon the elimination of propranolol and fluoxetine through adsorption. It was identified from this work that pharmaceuticals within the aqueous phase degraded under anaerobic conditions as predicted, while pharmaceuticals associated with the biosolids were removed through adsorption and present a potential threat to the environment on the disposal of treated biosolids. This work supports the current industry assumption that anaerobic treatment of biosolids offers limited opportunity for the removal of adsorptive pharmaceuticals, and also found no evidence for their enhanced removal under redox-controlled conditions. While research described within this thesis increases knowledge of the behaviour of pharmaceuticals in sewage sludge under anaerobic conditions, data is presented for a limited range of test substances only, and further investigation into the behaviour of additional compound classes is recommended.
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Holloway, Ryan W. "Forward osmosis for concentration of anaerobic digester centrate". abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1436020.
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Shaaban, M. G. B. "Scale-up studies on anaerobic dispersed growth digesters". Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372310.
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Bouaziz, Alexandre N. (Alexandre Nathanel). "Design of an anaerobic digester in Quebec, Canada". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90008.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 81-84).
.In response to the future Quebec, Canada regulations prohibiting landfilling of organic matter by 2020, EBI, a waste management company located near Montreal is considering constructing an anaerobic digester. This thesis focuses on designing a scalable prototype based on the waste types available from the existing facilities of the company and the Montreal area. Based on an extended literature review and a feedstock analysis realized for this project, the study covers the elements composing an anaerobic digestion facility, the design criteria and calculations as well as a preliminary cost assessment and scalability strategy to help EBI realize the project.
by Alexandre N. Bouaziz.
M. Eng.
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Brooks, Dana L. "Potential for methane digesters on U.S. dairy farms". Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15664.
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Master of AgribusinessDepartment of Agricultural Economics
Christine Wilson
Methane digesters are a potential investment for a dairy farm. A digester can lower greenhouse gas emissions, manage manure waste, generate energy, provide fertilizer and recycle bedding. The AgSTAR project of the Environment Protection Agency describes anaerobic digesters as a solution to a problem dairy farmers have always had to solve but that has become more acute with the innovation of larger scale, confined animal feeding operations developed in response to the growing food demands of the world’s larger and more prosperous middle class population – what to do with cow manure. Digesters take cow manure and convert it into energy while also eliminating manure odor. Energy is the primary economic benefit of a digester. A dairy farmer can use the electricity or gas generated from the digester to fuel the energy needs of the farm. Selling gas or electricity on the market is a revenue source that largely determines the level of profit from investing in a digester. This thesis will explore the four economic factors required to make anaerobic digesters a viable economic investment for a 1,500 head cow herd in the United States. It is imperative that farmers are able to obtain a return on the investment as soon as possible as many do not have the capital to invest in a nearly $1 million project. Congress may need to provide additional incentives for farmers and utility companies to take waste and process to energy. The future for methane digesters looks profitable when energy and carbon markets are available and allowed to trade competitively. The federal government may consider focusing on incentives for the utility companies’ infrastructure to make purchases of renewable energy from a digester more economically attractive and efficient. Today, an obstacle for increasing the number of digesters in the United States is the cost associated with moving the energy from the digester and into the national natural gas to grid. Natural gas companies may need to be compensated for that expense plus the potential difficulties of dealing with multiple suppliers or digester owners. Electricity companies have a grid in place to power rural and urban communities. They have spent billions of dollars and decades to establish efficient routing of power to residents and businesses. Manure digesters are mostly located in rural areas that would also require an investment in infrastructure to move the energy from the digester to the power grid. Mandating net-metering would require energy companies to purchase renewable energy, but consumers may see an increase in their cost. Therefore, the answer to increasing the number of manure digesters in the United States may be to direct the incentives to utility companies to invest in expanding infrastructure rather than increasing digester owner subsidies. Although, the REAP grants are helpful for assisting farmers with startup installation costs, there may not be a need to increase that subsidy in the next farm bill if an energy bill includes incentives for energy companies to purchase renewable energy from digesters.
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Clements, Laura. "The suitability of anaerobic digesters on organic farms". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/354422/.
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Food and energy security are two key environmental challenges currently faced by mankind. The principles behind organic farming are to promote environmental sustainability; however within the organic standards the use of renewable energy is only a suggested method with which to achieve this. If organic farmers can successfully utilise anaerobic digesters, they could contribute towards the provision of both food and energy security using one holistic system. Within this thesis, the suitability of anaerobic digesters on organic farms was explored using methods from ecological, sociological and environmental sciences. This enabled both the practical and theoretical issues behind the question of whether it is suitable for anaerobic digesters to be used on organic farms to be addressed. Field and laboratory experiments were used to compare the effects digestate and slurry had on earthworms, grass and weeds. Digestate and slurry had species dependent effects on earthworms during both LD50 / LT50 experiments and behavioural bioassays; Lumbricus terrestris survived longer in slurry and showed a behavioural preference towards slurry over digestate, whereas Eisenia fetida showed the opposite responses. Fertiliser application rates over 170 kg N ha-1 were found to be harmful to both species of earthworm. Suppressed germination effects were seen on thistles treated with digestate compared with no treatment (F0.56,19.66 =4.66, P < 0.01), whilst grass fertilised with digestate had a greater total mass than grass fertilised with slurry or left unfertilised (F2,27 =17.92, P < 0.001). Questionnaires and interviews were used to obtain a better understanding of the opinions farmers had about anaerobic digesters. Organic farmers believed renewable energy generation fitted well within organic principles, but using an anaerobic digester on an organic farm was less practical than on a conventional farm. This was due to multiple reasons including lack of information, poor associated finances, and that existing digesters are currently unsuitable for small organic farms. There was also support for anaerobic digesters to be on dairy farms- this was regardless of whether the farm was organic or conventional. Two case-study farms were used to assess the impact an anaerobic digester would have on the farms total GHG emissions. An anaerobic digester on the dairy farm was calculated to reduce GHG emissions by up to 24%, while for the mixed farm, the maximum reduction was by 20%. This was primarily due to the fact that the dairy farm benefitted from a higher volume of feedstock and proposed to use the biogas in a more energy efficient manner by producing electricity rather than vehicle fuel. Due to the high emissions associated with keeping livestock, both case studies needed to import additional feedstock if the farms were to achieve zero net GHG emissions. The answer to whether anaerobic digesters can be suitable for organic farms was judged on how well they complimented or conflicted with IFOAM’s definition of organic farming. Three main aspects of their definition were chosen and evidence from each chapter used to address the main question of the thesis. In conclusion, anaerobic digesters are theoretically suitable for use on organic farms, but are generally more practical for use on conventional farm systems. Across both farm systems the most suitable enterprises to adopt anaerobic digesters are dairy farms. This highlights the need for suitability of new systems to be assessed on a case-by-case scenario when trying to maximise positive impacts from new technologies.
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Jeyanayagam, Samuel S. "Engineering analysis of a Chinese-type anaerobic digester". Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49800.
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Davis, Owen S. "Heat transfer through anaerobic digester concrete tank walls". Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29909.
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This dissertation is a study of the heat transfer through concrete walls in anaerobic digester facilities. In the biogas industry, the term “heat loss” is synonymous with heat transfer. The dissertation identifies the reasons why heat is critical in the operations of these facilities. Concrete has traditionally been a material used for the retention of liquid-based products and additionally provides good thermal insulating properties. It combines the benefits of being relatively cost effective for the construction of large tanks and requiring low maintenance during the operational life span. The research focuses on the thermal properties of the various constituents of concrete and the influence these have on the overall thermal properties of the concrete tank. The constituents forming part of the study are cement, corex slag, water, fine and coarse aggregate. The study showed that the aggregates have a greater influence on the thermal conductivity than the other constituents. It also showed that the mineral composition of the aggregates has a greater effect on the thermal conductivity than the porosity of the aggregates. The study also looked at the influence of the interfacial transition zone around the aggregate and this was found to be not significant and generally can be ignored as a contributor to the thermal conductivity of normal / structural concrete. The effects of the porosity of the binder paste does affect the thermal conductivity specifically when aqueous solutions are being retained. The capillary pores of the paste can be filled with liquid (mainly water) and less with air. Due to water having a higher thermal conductivity than air, the thermal conductivity of the binder paste is significantly increased. The effects of reinforcement on the thermal conductivity of concrete was also investigated. Different types and arrangements of reinforcement could have a big influence. Steel fibres and reinforcement if aligned in the direction of the thermal gradient will greatly increase the thermal conductivity. However, it was found that the reinforcement used in the sample wall did not increase the thermal conductivity significantly as it was mainly aligned perpendicularly to the direction of the thermal gradient. Similarly, no steel fibres were used in the concrete. Once the thermal conductivities of the constituent materials were determined, the effective thermal conductivity of the concrete could be calculated using the effective medium theory. The subsequent heat losses, which are a function of the thermal conductivity, the temperature gradient between the internal and external faces of the concrete wall, the contact surface area and the heat transfer coefficient, could be calculated as a function of time. The New Horizons Waste to Energy Project in Cape Town was used as a reference project and the research was based on the materials used in the construction of the concrete anaerobic tanks. The project was also used for the measurement of the temperature gradients and subsequent calculation of actual heat losses at various points along the concrete walls. Furthermore, a computational model was developed using Abaqus to compare the results with those derived from the theoretical model. The heat loss from the computational model compares very well with that of the theoretical model.
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Murambadoro, Daniel K. "The structural performance of egg-shaped sludge digesters". Master's thesis, University of Cape Town, 2003. http://hdl.handle.net/11427/5019.
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Lehtinen, Silja. "Building a Small Scale Anaerobic Digester in Quelimane". Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214458.
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Anaerobic digestion is a process where biogas is generated from organic substance in the absence of oxygen. The most common application of the anaerobic digestion technology in developing countries is small-scale household digesters producing biogas for cooking purposes. These systems are usually fed with cattle dung or organic household waste. The typical small-scale digester models are fixed-dome digester, floating-drum digester and rubber-balloon digester. Biogas systems contribute to self-sustainability of energy production, improve waste management and mitigate deforestation and health problems caused by poor waste management and usage of traditional cooking fuels such as firewood and charcoal. Anaerobic digestion technology is still quite unknown in Mozambique. An initiative to implement this technology in the municipality of Quelimane located in Zambézia province in the central part of the country, was taken in 2015 and background studies were performed during spring 2015 and 2016. As a part of the study resulting in this report, performed in spring 2017, a small-scale biogas digester was installed in Quelimane city. The digester was fed with the initial input of cow manure in order to create population of anaerobic bacteria and in the future it’s planned to be fed with food waste. The purpose of the first installed digester is to serve for educational purposes and to produce cooking fuel for the few people working in the municipal location where the digester is installed. It’s estimated that the digester has a potential to produce daily 0.3 m3 of biogas from 2 kg of food waste which can be used for preparing lunch for the employees or for heating water. In the future, possible applications of anaerobic digestion technology in Quelimane are a municipal biogas plant, cooling systems for the fish industry and biogas based latrines in the less developed areas located outside of the city center.
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Conklin, Anne. "Acetoclastic methanogenesis : a key to anaerobic digester stability /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10131.
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Plouchart, Diane. "Experimental coalescence of microbial communities in anaerobic digesters". Thesis, Montpellier, SupAgro, 2018. http://www.theses.fr/2018NSAM0009/document.
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La digestion anaérobie est un procédé biologique effectué par un réseau complexe et synergique de communautés microbiennes permettant la dégradation de matière organiques comme les déchets agricoles ou les effluents de station d’épuration en biogaz, un gaz valorisable en énergie. Les mécanismes influençant les communautés microbiennes au cœur de ce procédé mais aussi dans la nature restent incompris du fait de la faible compréhension de leur dynamique. Les objectifs de ce projet visent à donc développer un système de digestion anaérobie permettant de mieux comprendre la dynamique de l’assemblage des communautés microbiennes. Ainsi un nouveau procédé de réacteurs en continu dont les fonctions d’alimentation de soutirage et de dégazage sont automatisées a été développé. L’automatisation et le multiplexage des réacteurs permettent la manipulation de 30 réacteurs en continu en parallèle. Outre l’automatisation ce système, de nombreux paramètres sont flexibles comme le taux de charge (une fois par minute jusqu’à une condition batch), le volume de réacteur (50 à 200mL), la température (pièce – 55°C), mais aussi l’utilisation du système en aérobie ou l’implémentation d’autres outils comme des LEDs pour les cultures phototrophes. Capable de quantifier précisément la performance d’un écosystème méthanogène, ce système nous a permis de tester la structure et la performance d’écosystèmes méthanogènes mis en mélanges et testés de façon individuelle. En mélangeant des écosystèmes méthanogènes différents, la diversité des Archées a augmenté transitoirement. Une corrélation est d’ailleurs observée entre la diversité de ces communautés mélangées et leur performance méthanogène, seulement à même diversité les communautés individuelles ont un meilleur fonctionnement. L’assemblage de certaines communautés mélangées a pourtant permis une meilleure production de méthane que les communautés individuelles, ce qui suggère le développement d’interactions spécifiques de ces communautés. De façon nouvelle par rapport à la littérature, la majorité des communautés bactériennes individuelles sont retrouvées dans les communautés mélangées. Soit contrairement à l’idée d’une sélection d’une communauté plus adaptée ou plus fonctionnelle, ici la majorité des communautés se sont implantées. Ces expériences suggèrent qu’un paramètre tel que la fonctionnalité d’un bioprocédé peut-être amélioré par bioaugmentationAnaerobic digestion is a biological process carried out by a complex and synergistic network of microbial communities allowing the degradation of organic matter such as agricultural waste or effluents from wastewater treatment plants, into biogas, a gas recoverable into energy. The mechanisms influencing microbial communities at the heart of this process but also in nature remain misunderstood because of a low understanding of their dynamics. The objectives of this project are therefore to develop an anaerobic digestion system to better understand the dynamics of microbial community assembly. Thus, a new continuous reactor process has been developed with automated feeding, biomass wasting and degassing functions. Automation and multiplexing of reactors allows for the continuous parallel manipulation of 30 reactors in parallel. In addition to the automation, many parameters are versatile, such as the substrate loading (once a minute up to batch conditions), the reactor volume (50 to 200 mL), the temperature (room to 55°C), but also the use of the aerobic system or the implementation of other tools such as LEDs for phototrophic cultures. Capable of accurately quantifying the performance of a methanogenic ecosystem, this system has enabled us to test the structure and the performance of five different methanogenic ecosystems that have been mixed and tested individually. By mixing different methanogenic ecosystems the Archaea diversity has increased transiently. Besides, a correlation is observed between the diversity of mixed communities and their methanogenic performance; yet the individual communities have a better functioning at the same level of diversity. Interestingly, the mixture of some communities has allowed for better methane production than individual communities, suggesting the development of specific interactions in these communities. In a novel way compared to the literature and that the majority of individual bacterial communities are found in mixed communities. Contrary to the idea of selecting a more adapted or functional community, here the majority of communities have settled. These experiments suggest that a parameter such as the functionality of a bioprocess can be improved by bioaugmentation
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Tcha-Thom, Maglwa. "Recherche d'une filière durable pour la méthanisation des déchets de fruits et d'abattoirs du Togo : Evaluation du potentiel agronomique des digestats sur les sols de la région de la Kara". Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0061/document.
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La digestion anaérobie, procédé d’énergie renouvelable, constitue un atout indéniable de récupération des flux matière et énergie des déchets en réponse aux enjeux du développement durable. Ainsi, la présente étude a pour objectif de contribuer à la compréhension des mécanismes qui gouvernent l’environnement réactionnel de digestion en anaérobie et les effets des digestats sur la matrice bio-physico-chimique des sols à vocation agricole. Le développement des tests de lixiviation en réacteurs contrôlés aérobie et anaérobie, les modes de mobilisation du contenu organo-minéral des substrats et la valorisation du biogaz pour l’équarrissage des bêtes ont été réalisés. Les verrous techniques et physico-chimiques entachant la digestion anaérobie des déchets d’ananas ont été levés et optimisés grâce à des co-substrats notamment les bouses de vache et les cendres. Les digestats ont été apportés sur des sols agricoles, des sols des zones de forêts et des milieux sans matière organique ni argiles et ont permis de déceler les limites d’utilisation des digestats et les interactions avec les fractions organiques et minérales du sol. Cette étude montre ainsi, l’importance de développer la filière de méthanisation pour une élimination durable des déchets organiquesAnaerobic digestion, a renewal energy process, constitutes an undeniable asset of material and energy flows recovering in response to sustainable development issues. Thus, the aim of this current study was to contribute to the understanding of mechanisms that govern the reactive environment of anaerobic digestion and the effects of digestates on the biophysico- chemical matrix of agricultural soils sector. The running of leaching tests in aerobic and anaerobic controlled reactors, organo-mineral mobilizations patterns of the substrates and the valorization of biogas in slaughtered animals knackering have been realized. The physicochemical and technical locks tarnishing the pineapple wastes anaerobic digestion have been lifted and optimized through the co-substrates including cattle manure and ashes. The digestates have been brought on agricultural soils, forests areas soils and medium free of organic matter and clays and allowed to detect the limits of digestates uses and the interactions with organic and mineral fractions of soils. This study, thus show, the importance to develop the anaerobic digestion sector for a sustainable removal of organic wastes
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Ducreux, Michel. "Tumeurs neuroendocrines : nouvelles approches diagnostiques et thérapeutiques, facteurs pronostiques". Dijon, 2000. http://www.theses.fr/2000DIJOMU16.
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Les tumeurs neuroendocrines (tne) sont des tumeurs rares dont le point de depart est le plus souvent digestif. Les objectifs de ce travail ont ete de definir la place des nouveaux examens, l'efficacite des nouvelles therapeutiques permettant d'ameliorer la strategie diagnostique et therapeutique de ces tumeurs. Apres une premiere etude demontrant le peu d'interet de la recherche de catecholamines urinaires, une seconde etude a montre que la chromogranine a etait plus sensible et avait une meilleure valeur predictive positive que l'enolase neurone-specifique. Enfin une grande etude de screening menee chez 130 patients consecutifs a determine les recherches hormonales qu'il fallait effectuer en fonction du siege de la tumeur. Bilan limite en cas de tne du grele ou de l'appendice, bilan plus exhaustif en cas de tne pancreatique. Apres la demonstration d'une equi-efficacite du lanreotide par rapport a l'octreotide dans le traitement du syndrome carcinoidien, une etude de phase ii a evalue l'effet anti-tumoral de ce nouvel analogue de la somatostatine. Quarante-six patients ont ainsi ete traites par le lanreotide administre tous les 15 jours.
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Waelkens, Barbara Elisabeth [Verfasser], e Ralf [Akademischer Betreuer] Takors. "Investigation of high load anaerobic digester design parameters : effect of reaction kinetics on digester design recommendations / Barbara Elisabeth Waelkens ; Betreuer: Ralf Takors". Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2020. http://d-nb.info/1215101929/34.
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Genevois, Sandrine. "Intérêt de l'endoscopie digestive haute systématique chez l'insuffisant rénal chronique avant le début de la dialyse : étude rétrospective de 72 sujets réunionnais". Bordeaux 2, 1998. http://www.theses.fr/1998BOR2M063.
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Nguyen, Vo Chau Ngan. "Small-scale anaerobic digesters in Vietnam - development and challenges". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-88525.
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Small-scale anaerobic digesters, known as biogas plants, were applied as an optimal livestock waste treatment as well as biogas supply for cooking and lighting demand for small-scale farmers in Vietnam. Although the biogas technology was introduced for nearly 30 years, the number of the constructed biogas plants is still limited. The current development of biogas plants is far below the real demand on livestock waste treatment that has increased significantly. This paper gives a comprehensive overview on the biogas plant development in Vietnam and attempts to address the challenges and discuss appropriate solutions for the further biogas developmentMô hình lên men yếm khí quy mô nhỏ (được biết với tên hầm ủ khí sinh học) đã được ứng dụng hiệu quả trong xử lý chất thải chăn nuôi cũng như cung cấp nguồn nhiên liệu phục vụ nhu cầu nấu ăn và thắp sáng cho các hộ chăn nuôi nhỏ ở Việt Nam. Mặc dù đã hiện diện gần 30 năm, nhưng số lượng hầm ủ khí sinh học vẫn còn hạn chế. Sự gia tăng số lượng hầm ủ khí sinh học chưa theo kịp với nhu cầu về xử lý chất thải chăn nuôi đang ngày càng gia tăng. Bài báo trình bày các chặng đường phát triển của hầm ủ khí sinh học tại Việt Nam, ghi nhận các thách thức trong việc nhân rộng hầm ủ khí sinh học trong thực tế và thảo luận một số giải pháp để phát triển công nghệ khí sinh học
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Albadvi, Elham. "Measuring uniformity in kraft digesters using flow-following sensors". Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/29411.
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Measurements of pulp variability and temperature distributions within kraft digesters have been the subject of intense interest for many years. An extensive survey carried out on the previous approaches to measure digester variability has shown that data directly taken from within the digester, during the kraft cook is scarce. Moreover, the increased size of modern digesters is believed to reduce the flow uniformity within them, increasing the risk of pulp variability and highlighting the need to collect data from within the digesters themselves. This has motivated the development of a new method for measuring digester variability: the “SmartChip”. This device is a flow-following sensor package that measures and records the temperature directly within the digester during the kraft cook.
This research proposes a theoretical model to describe the heat transfer mechanisms occurring within the digester and then uses the data captured by the SmartChip to measure the digester variability. Preliminary test trials were conducted to ensure that the SmartChip could withstand the harsh environment of the kraft cook. Subsequently, multiple SmartChips were deployed in a single cook to provide insight on the temperature variability and heat transfer mechanisms occurring within the digester and these experimental results were then be compared with the predictions of the proposed model. Moreover, by taking pulp samples in the vicinity of the SmartChip sensors, the relation between nonuniformity and temperature gradients is established.
The SmartChips have been tested in two laboratory batch digesters and as expected, temperature was already well-controlled within them and little variability was observed in these small-scale devices. Moreover, a good agreement is found between the model predictions and the experimental results and the model is experimentally validated, showing that the heat transfer through the digester contents is by pure advection with almost negligible thermal energy required for the heating of wood chips. These findings further suggest that the SmartChip works well under the harsh conditions of the kraft cook and future work is warranted to develop the instrument for its use at the industrial scale, where the temperature fluctuations along the digesters are more noticeable.
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Fell, Christopher John. "Monitoring and control of anaerobic digesters treating industrial effluents". Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/32621.
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Increasing charges by the private utilities for the treatment of industrial waste water are making on-site effluent treatment more attractive. On-site anaerobic digestion is increasingly being used by food processing factories as a cost effective solution to waste liquid waste disposal. Discharge of treated effluent to sewer or water course requires compliance to a maximum admissible concentration (MAC) value, therefore, there is a need for careful control of on-site waste water treatment. This research investigates the treatment of effluent from instant coffee production. This results in a liquid waste that contains recalcitrant and toxic compounds formed during the roasting process. This waste varies in strength and composition according to the different processes that are performed in the manufacture of instant coffee. Anaerobic filters are particularly attractive for wastes containing recalcitrant or inhibitory compounds requiring a long sludge age. Therefore, this study was aimed at firstly investigating the treatability of coffee waste, using anaerobic filters; and secondly monitoring and control of the digestion process in order to maintain a constant effluent quality.
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Castano, Juan Mauricio. "Anaerobic Digestion of Low Rate Digesters in Temperate Climates". The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345220853.
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Jiang, Anping. "Ammonia recovery from digested dairy manure as nitrogen fertilizer". Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Dissertations/Fall2009/a_jiang_010509.pdf.
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Thesis (Ph. D.)--Washington State University, December 2009.Title from PDF title page (viewed on Feb. 19, 2010). "Department of Biological Systems Engineering." Includes bibliographical references.
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Gibson, Leia. "Microalgal cultivation to treat anaerobically digested domestic effluent (ADDE)". Thesis, Gibson, Leia (2020) Microalgal cultivation to treat anaerobically digested domestic effluent (ADDE). Masters by Research thesis, Murdoch University, 2020. https://researchrepository.murdoch.edu.au/id/eprint/59417/.
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In this study, the cultivation of microalgae in anaerobically digested domestic effluent (ADDE) was evaluated. Based on the knowledge from other literature, this is the first study of its kind. The ADDE was sourced from a local wastewater treatment plant (WWTP) which had a total ammonia content of approximately 1000 - 1500 mg L-1 NH3+-N. The overarching aim of this study was to identify the optimal nutrient concentration to maximise the growth of the mixed microalgal consortium (Chlorella and Scenedesmus species) in the ADDE supernatant. Apart from this, the growth comparison of microalgae cultivated in sand-filtered and unfiltered, ADDE supernatant was also assessed.
In this research, two experimental studies were conducted. The first study evaluated the growth of the mixed microalgal consortium in different dilutions (25%, 50%, 75% and 100%) of the unfiltered, ADDE supernatant. Based on the first study, the mixed consortium produced the highest mean specific growth rate (μ) in higher dilutions (25% and 50%) of the unfiltered, ADDE. The observations from the first study led to the creation of the second experiment, which observed the same consortium in the sand-filtered and unfiltered, ADDE at 25% and 50% dilution. No statistical difference, however, was observed between the average biomass productivities (Pr) and μ of different treatments in the second study. The algal growth, however, in the 50% diluted, unfiltered ADDE treatment (50% UA treatment) possessed a higher μ when compared to the other treatments.
The 50% UA treatment was also the most efficient treatment at removing nitrogen sources in comparison to the other treatments. It removed 63% and 77% more total nitrogen (ammonia, nitrate and nitrite) when compared to the average removal rates of the same nitrogen sources observed in other treatments. No statistical difference was, however, detected between the mean nitrogen (ammonia, nitrate and nitrite) removal rates of all treatments.
The mixed consortium in all treatments was, however, not very efficient at removing phosphorus and COD. The mean phosphate removal rates observed in this second study was also much lower when compared to the phosphate or total phosphorus removal rate reported in other literature. The cause for this might be due to the non-ideal N: P ratio of the wastewater. The unfiltered, ADDE supernatant contained higher levels of phosphorus instead of ammonia. More nitrogen is typically required for microalgal growth instead of excess phosphorus which makes only 1% of the microalgal dry weight. In terms of COD removal inefficiency, microalgal cells can release substances that increase COD levels, especially in conventional microalgae-based wastewater treatment systems (WWTS). Most of the COD in wastewater are also non-soluble and take a long time to biodegrade.
As for the aerobic bacteria population observed in the second study, no statistical difference was detected between the aerobic cell counts of different treatments on day 0, 1 and 3. There was an increase (by about 40% - 50%) in aerobic bacterial cells observed in all treatments between day 1 and 3. An average of 1× 107 CFU mL-1 aerobic bacteria cells was observed in all treatments towards the end of the experiment of the second study. There were no E.coli or coliform bacteria observed in all the treatment replicates through the entire experimental period of the second study.
In terms of heavy metal absorption, the same consortium that was grown in the 50% UA treatment, removed about 21% and 25% of Cd, Cr and As. The microalgal biomass cultivated in this treatment was more efficient at assimilating Cr and Cd over As. The concentration of As and Cd present in the mixed consortium’s biomass was respectively, about 83% - 99% higher than the maximum levels of these heavy metals (HMs) recommended by the Codex Alimentarius set by the FAO. It is unknown if the Cr levels in the mixed consortium’s biomass exceed the maximum levels since it was not stated in the Codex Alimentarius.
While the 50% UA treatment was the most efficient at removing nitrogen sources (ammonia, nitrate and nitrite) in comparison to the other treatments. It was still relatively low in comparison to nitrogen (nitrate, nitrite and ammonia) removal rates reported in other published studies. The phosphorus or phosphate removal rates published in other studies were also much higher in comparison to this research. Based on the heavy metal analysis; the microalgal biomass produced in the same treatment, cannot be used to produce food and feed. It does not meet the international safety standards outlined in the Codex Alimentarius set by the FAO. The high level of aerobic bacteria detected in all treatments was due to the dissolved oxygen produced by the photosynthetic activity of microalgal cells. More work is still required before this indoor lab study can be conducted outdoors. Further analysis is needed to fully understand how to optimise the growth of this consortium in the ADDE supernatant.
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Wahal, Shantanu. "Nutrient Utilization from Anaerobic Digester Effluent Through Algae Cultivation". DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/671.
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Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI and later identified to be closely related to Chlorella vulgaris) from the wastewater treatment lagoons in Logan, UT. All tested strains could be adapted to the effluent to enhance the utilization of native nutrients present in both organic and inorganic forms. There was a marked improvement in growth rates (up to 4.8-fold) and biomass production (up to 8.7-fold) of algal cultures after they adapted to the effluent. Also, effluent-adapted strains were able to switch from phototrophy to heterotrophy to prolong the growth when light availability became limited. However, an increase in irradiance levels in light-limited cultures led to resumption of phototrophic growth. It was found that this approach of light supplementation prolonged growth and increased biomass production (up to 2.7-fold) in algal cultures. Of all the strains tested, the isolate from the wastewater treating lagoons grew to highest culture densities and produced the highest concentration of intracellular triacylglycerides (TAG). This culture also grew best in non-sterile, native effluent and could reach biomass concentration of up to 4.5g/L with TAG content of approximately 10% (w/w). Culture densities were lower when this organism was grown in sterilized effluent or in sterile artificial media, suggesting that this organism symbiotically associated with other microbes in digested animal waste. Findings of this research study suggest that microalgae can be grown efficiently on inexpensive natural substrates in non-sterile growth conditions. When commercially implemented, biodiesel production from such systems could be more cost effective and sustainable.
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Adler, Neal Cary. "Dairy Manure Flushwater Treatment by Packed-Bed Anaerobic Digesters". DigitalCommons@CalPoly, 2013. https://digitalcommons.calpoly.edu/theses/1025.
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Wastewater treatment performance of three pilot-scale packed-bed anaerobic digesters with walnut shell medium was researched for treating dairy freestall barn flushwater. Reciprocation mixing was evaluated as a means to lessen channelization in the media bed and to improve biogas production and organic matter removal at ambient temperatures. Reciprocation has been used in biological nitrogen removal systems to introduce air into the system to repeatedly oxygenate nitrifying biofilm along with mixing (Behrends et al. 2003), but the anaerobic systems benefit from mixing. Two tanks were used in each system, where one was full and one was empty at any given time. Water was repeatedly pumped from one tank to the other and back again (reciprocation). A key research objective was to determine the minimum reciprocation frequency (between 0-10 per day) while still maintaining moderate methane production and treatment performance. Broken walnut shells with a specific surface area of 360 m2/m3 were used as the packed media. Digester influent, which was pretreated to remove large solids, had the following characteristics: total solids (TS) of 5.5 g/L, volatile solids (VS) of 2.8 g/L, 5-day carbonaceous biochemical oxygen demand (cBOD5) of 800 mg/L, and chemical oxygen demand (COD) of 4340 mg/L. Average digesting liquid temperatures ranged from 14.1 to 23.6 °C. At 6-day theoretical hydraulic residence times (V/Q where V is Lliquid, which is volume of liquid occupying the digester pores, and Q is total daily influent flow) and 1 reciprocation per day, methane production was 0.060 ± 0.10 LCH4/Lliquid-day and at 10 reciprocations methane production 0.058 ± 0.14 LCH4/Lliquid-day (mean ± standard deviation of measurements over time). COD percent removals were both 51% at 6-day V/Q. Since multiple reciprocations did not appear to make a difference in methane production and treatment performance, fewer reciprocations were used in subsequent experiments. Higher flow rates were also used in subsequent experiments to accelerate sludge clogging and channelization in the walnut-shell bed and thereby allow detection of any advantage provided by reciprocation compared to an upflow reactor. At 0 and 1 reciprocations per day and 0.35 and 0.50-day V/Qs, respectively, methane production was 0.24 ± 0.08 and 0.23 ± 0.08 LCH4/Lliquid-day and COD percent removal was 17 and 22%. Over the study period of 226 days, walnut shell porosities decreased due to sludge accumulation from 0.68 and 0.64 (start-up or clean-bed) to 0.31 and 0.24 in the 1 and 0 reciprocation per day reactors. Sludge accumulation and channelization did not appear to be affected by reciprocation mixing on the scale of this study.
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Almeida, Érika Hotz. "Digestão ácida em diptera superiores". Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/46/46131/tde-18092015-160208/.
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Insetos abrangem o maior número de espécies descritas, estando distribuídos por praticamente todos os nichos ecológicos. O tubo digestivo destes animais consiste na principal interface entre estes e o meio externo. Assim, o estudo das enzimas digestivas, ou proteínas relacionadas ao processo digestivo em insetos, faz-se fundamental para a tentativa de desenvolver novos métodos de controle que ajam via canal alimentar, como o uso de plantas transgênicas para controlar insetos fitófagos (Felton & Gatehouse, 1996). Diptera superiores são os únicos animais, além dos vertebrados, que apresentam uma região ácida em seu intestino médio (Vonk & Western, 1984). Assim, o estudo da digestão ácida nestes organismos permite-nos examinar em detalhe este interessante paralelismo evolutivo (muito revelador se incluir também aspectos moleculares). Para realização deste estudo foram escolhidas duas enzimas relacionadas com a digestão ácida em Diptera: uma aspártico-proteinase de Musca domestica, semelhante à catepsina D, e uma lisozima digestiva de Drosophila melanogaster. Para purificar a aspártico-proteinase intestinal de M. domestica, ventrículos anterior e médio de larvas deste inseto foram homegeneizados e centrifugados, sendo o sobrenadante resultante utilizado como fonte de enzima. A combinação de uma cromatografia em coluna de troca iônica seguida de uma filtração em gel mostrou-se como a melhor para a obtenção da aspártico-proteinase intestinal de larvas de M. domestica totalmente purificada. Clones de lisozima de D. melanogaster (LysD) e de A. darlingi (Lysdar) foram utilizados na construção de vetores de expressão a seguir usados na transformação de E. coli linhagem OrigamiTMB (DE3) e P. Pastoris GS115 (his4). As bactérias transformadas com vetor pT7-dar (que continha o gene Lysdar), quando induzidas por IPTG, foram capazes de expressar uma proteína, cujo peso molecular em gel de SDS-PAGE é de cerca de 14 kDa, como o esperado. A lisozima hipotética foi encontrada em corpos de inclusão, que solubilizados por SDS 3% resultaram em proteína inativa. Colônias de P. pastoris transformadas com o vetor pPIC-9-D (contendo o gene LysD) foram submetidas a reação em cadeia com DNA polimerase. Aquelas que geraram produtos de PCR de tamanho coerente com o de uma lisozima foram cultivadas e posteriormente, induzidas por metanol. P. pastoris é capaz de secretar a lisozima induzida. Assim, alíquotas do meio de indução foram utilizadas em ensaios enzimáticos para a detecção da atividade da lisozima intestinal de D. melanogaster. A lisozima é expressa em P. pastoris em grande quantidade (12 mg/L) e com atividade preservada. Foi verificado que há uma intima relação entre a força iônica do meio e o pH ótimo da lisozima intestinal recombinante de D. melanogaster. O pH ótimo é deslocado para valores mais ácidos quando em forças iônicas maiores. Em contrapartida, os valores de atividade obtidos para a lisozima D recombinante de D. melanogaster decrescem com o aumento da força iônica do meio.Insects are the most numerous of living beings and are found in almost all habitats. The midgut of these animals is the main interface between them and their enviroment. Thus, the study of digestive enzymes or of other proteins relateded to the insect digestive process is putatively useful for the development of new insect control strategies. Houseflies (higher Diptera) are the only animals, besides vertebrates, that present an acidic region in the midgut (Vonk & Western, 1984). Due do that, a detailed analysis of the acidic digestion in these insects may disclose molecular evolutionary paralellisms between those animals. Two enzymes were chosen along the aims discussed: a Musca domestica aspartic-proteinase, similar to cathepsin D and a digestive lysozyme from Drosophila melanogaster. To purify the cathepsin D-like proteinase from M. domestica larvae, larval foreguts and midguts were homogeneized, centrifuged, and the resulting supernatant was used as an enzyme source. Ion-exchange chromatography followed by a gel filtration of enzyme extract resulted in a homogeneous preparation of the enzyme. Clones of lysozyme from D. melanogaster (LysD) and A. darling (Lysdar) were used in the construction of expression vectors, which were used to transform E. coli cells (OrigamiTM B(DE3)) and P. pastoris GS115 (his4). Bacteria transformed with pT7-dar (the expression vector which contained the gene Lysdar), when induced by IPTG, expressed a protein with a molecular weight of 14 kDa, as expected for lysozyme. This protein was found in inclusion bodies that were solubilized in 3% SDS resulting in a protein with no activity. After choosing at random P. pastoris colonies transformed with the expression vector pPIC9-D (containing the gene LysD), they were submited to a PCR. The colonies with 366pb products were grown and induced by methanol. P. pastoris was engineered to excrete the expressed proteins. In accordance to that, about 12 mg of lysozyme were recovered from each litter of culture medium. Recombinant D. melanogaster lysozyme D was more active at acid pH values, when present in media with physiological ionic strengths, and its Km value increased with the ionic strength of media. This is agreement with data obtained with lysozyme D isolated from D. melanogaster midgut. The results support the assertion that this enzyme may be used in crystalographic and site mutagenesis studies to reveal the molecular basis of its catalytic properties.