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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Avaliação do desempenho de flotação por ar dissolvido no tratamento de efluente de refinaria de óleo de soja / Valuation of performance of dissolved air flotation on treatment of wastewaters of soybean oil refining

Cecchet, Juliana 06 July 2007 (has links)
Made available in DSpace on 2017-07-10T19:24:01Z (GMT). No. of bitstreams: 1 Juliana Cecchet.pdf: 2090330 bytes, checksum: 58b3febaf50310456ede4d0b8648a7f0 (MD5) Previous issue date: 2007-07-06 / The aim of this work was to value the performance of three types of coagulants, two of them of polichlorate of alum class and one of them was organic, combined to three polyelectrolytes class (anionic, cationic and no ionic) applying the dissolved air flotation (DAF), to viability their use on treatment of effluents of soybean oil refinery. The study was conducted on laboratory scale where first was tested the coagulants on several dosages combined to several bands of pH and three ascension velocities (Va), finding a optimum band of this combination for one of each three batteries. For this, was fixed parameters how time and fast mixed gradient (1 min / 150 s-1), time and slow mixed gradient (10 min / 40 s-1 5 min / 20 s-1), pressure on saturation chamber (450 kPa) and recirculation ratio (30%). Finding the optimum concentration of coagulant (Cc ótima), optimum coagulation pH (pHcoag ótimo) and optimum ascension velocities (Vaótima), fix those parameters and then goes for a variation of polyelectrolyte, testing several dosages and finding a optimum concentrate of polyelectrolyte (Cf ótimo). Finally, with junction of all optimized parameters, was varied de recirculation rate (R) (10, 20 e 30%), choosing the best R and collecting samples for the determination of levels of turbidity, total suspended solids (TSS), volatile suspended solids (VSS), oil and greases (O&G) and chemical oxygen demand (COD) remaining on treated effluent presenting a percentage of remotion COD of 95,4%, 93,7% and 95,1% and O&G of 100%, 94,2% e 99,8% for the batteries 1, 2 e 3 respectively. Despite of being excellent efficiencies of remotion, the treated effluent was not present characteristics for the reuse on the cooling water towers, because its organics load on the raw effluent its too much higher and even with so good levels of remotion, still was necessary a pos treatment to think on reuse. / Este trabalho foi desenvolvido com o objetivo de avaliar o desempenho de três tipos de coagulantes, dois da classe dos PACs (cloreto de polialumínio) e um orgânico, combinados a três classes de polieletrólitos (aniônico, catiônico e não iônico), aplicando o uso de Flotação por Ar Dissolvido (FAD), para viabilizar seu uso em tratamento de efluentes de refinaria de óleo de soja. O experimento foi conduzido em escala de laboratório e primeiramente foram testados os coagulantes em diversas dosagens combinados a diversas faixas de pH e três velocidades ascensionais (Va), encontrando uma faixa ótima dessa combinação para cada uma das três baterias. Para tanto foram fixados parâmetros como tempo e gradiente de mistura rápida (1 min / 150 s-1) tempo e gradiente de mistura lenta (10 min / 40 s-1 5 min / 20 s-1), pressão na câmara de saturação (450 kPa) e razão de recirculação (30%). Encontrando-se a concentração de coagulante ótima (Cc ótima), pH de coagulação ótimo (pHcoag ótimo) e velocidade ascensional ótima (Vaótima). Fixados esses parâmetros foi verificada a variação do polieletrólito, testando-se em diversas dosagens e encontrando uma concentração de floculante ótima (Cf ótimo). Finalmente, com a junção de todos os parâmetros otimizados, efetua-se a variação da razão de recirculação (R) (10, 20 e 30%), escolhendo a melhor R e coletando-se amostras para a determinação dos níveis de turbidez, sólidos suspensos totais (SST), sólidos suspensos voláteis (SSV), óleos e graxas (O&G) e demanda química de oxigênio (DQO) remanescentes no efluente tratado apresentando um grau de remoção de DQO de 95,4%, 93,7% e 95,1% e de O&G de 100%, 94,2% e 99,8% para as baterias 1, 2 e 3 respectivamente. Apesar de serem eficiências excelentes de remoção, o efluente tratado não apresentou características de reuso em torres de resfriamento, pois sua carga orgânica no efluente bruto é muito alta e mesmo com níveis tão bons de remoção ainda seria necessário um pós-tratamento para se avaliar a possibilidade de reuso.
122

Tratamentos para redução de metais alcalinos, enxofre e cloreto em celulignina destinada à obtenção de gás de síntese como substituto do gás natural para geração de energia termoelétrica em turbinas a gás / Treatments for reduction of alkali metals, sulfur and chloride in cellulignin designed to obtain synthesis gas as a substitute for natural gas for thermoelectric power generation with gas turbines

Erica Leonor Romão 02 March 2011 (has links)
O presente trabalho se insere no Programa de Biomassa - Energia - Materiais - PROBEM?, cuja Refinaria de Biomassa desenvolve tecnologias para o aproveitamento integral de biomassas lignocelulósicas e oleosas, objetivando sua exploração autossustentada. Os principais produtos obtidos são combustíveis para geração de energia termoelétrica, produtos químicos, materiais inorgânicos e reciclagem de fertilizantes. Neste trabalho explorou-se a celulignina, que é um combustível obtido pela pré-hidrólise ácida da biomassa, visando à obtenção de gás de síntese (singás) da celulignina para geração de energia termoelétrica com turbinas a gás, como substituto do gás natural. Para essa aplicação, e também para aplicações em síntese de produtos químicos e combustíveis pelo processo Fischer Tropsch, teores de metais alcalinos, enxofre e cloretos são críticos. A biomassa considerada foi a madeira de Eucalyptus grandis. O trabalho propõe a lixiviação aquosa daqueles contaminantes por pré-hidrólise ácida da biomassa, seguida da moagem a úmido da celulignina para razões líquido/sólido (L/S) otimizadas em relação ao consumo de água e aos teores finais dos contaminantes na biomassa tratada. A eficiência da sequência de tratamentos foi verificada medindo os teores de potássio, sódio, cloreto e enxofre total após cada etapa de lixiviação da celulignina. A pré-hidrólise ácida do E. grandis foi realizada na presença de ácido sulfúrico como catalisador, com produção de cerca de 67% de celulignina e 34% de solução de açúcares, em relação à quantidade de biomassa seca inicial. Os resultados desta etapa do processamento mostraram uma redução no teor de potássio de 3,3 vezes e no teor de sódio de 1,9 vez na celulignina em relação ao E. grandis in natura. A celulignina assim obtida foi submetida a uma sequência de moagem a úmido em moinho de martelos. Resultados apontaram a razão L/S = 12 como mais eficiente. O singás obtido da celulignina apresentou teores estimados de K+ + Na+= 600 ppb, Cl-=1,4 mg/Nm³ e enxofre total = 4 mg/Nm³. Isso significa uma redução de 1000 vezes em K+ + Na+ em relação à biomassa bruta. Nessas condições, o gás de síntese obtido já seria similar ao singás do gás natural, podendo ser usado em turbinas a gás. As aplicações com o gás de síntese no processo Fischer Tropsch não estão descartadas já que as especificações do gás natural para essa mesma aplicação permitem um máximo de enxofre de 70 mg/Nm³. Melhoramentos nos procedimentos de análise química em todas as etapas do processo são necessários para levar a resultados mais acurados. Melhoramentos nos equipamentos de controle das emissões gasosas na geração do singás tendem a diminuir os teores de enxofre para os níveis previstos em norma (< 1mg/Nm³). / This work is part of the Program Biomass - Energy - Materials - PROBEM?, whose Biomass Refinery develops technologies for a self-sustaining exploration of lignocellulosic and oily biomass. The main products are fuels for thermal and electricity energy generation, chemicals, materials and recycled inorganic fertilizers. This work explores the cellulignin, which is a fuel obtained by acidic prehydrolysis of biomass aiming to produce synthesis gas (syngas) as a substitute for natural gas for themoelectrical energy generation with gas turbines. This application, and also for the Fischer Tropsch process, of alkali metals, sulfur and chlorine concentrations in the syngas must be very low. The selected biomass is Eucalyptus grandis. The main objectives are to promote the aqueous leaching of those contaminants from cellulignin by a sequence of treatments, and to obtain the syngas by gasification of the cleaned cellulignin. The aqueous leaching of contaminants is carried out by acidic prehydrolysis of the wood, followed by the wet grinding of cellulignin at different liquid / solid (L/S) rations optimized with respect to water consumption and the final concentration of contaminants in the treated biomass. The efficiency of the sequence of treatments was checked by measuring potassium, sodium, chloride and sulfur contents in the cellulignin after each leaching step. Prehydrolysis of E. grandis was carried out using sulfuric acid as a catalyst, producing 67% of cellulignin and 34% of hydrolysate in relation to the initial dry biomass mass. Results after prehydrolysis showed a reduction of 3.3 times in the potassium content and of 1.6 times for sodium in the unwashed cellulignin in relation to the E. grandis \'in natura\'. The cellulignin so obtained was wet-ground in hammer mill. Results showed the L/S = 12 as the more efficient ratio in the grinding step. After gasification of the cellulignin the estimated values of the contaminants in the syngas were K++Na+ = 600 ppb, Cl- =1,4 mg/Nm³, and total S = 4 mg/Nm³, similar to the syngas from natural gas specifications for those elements. This means that the syngas from the cellulignin can be used as a fuel in gas turbines, replacing the syngas obtained from natural gas. Yet, its application in the Fischer Tropsch process is not discarded because maximum sulfur content allowed in the natural gas for that application is 70 mg/Nm³. Improvements have to made on the analytical procedures to ensure more accurate results, and is also necessary to improve the efficiency of the equipments for gas emission control in the syngas generation process. The last improvement should lower the S content to the specification values for the syngas (< 1mg/Nm³).
123

Análise ambiental, energética e econômica de arranjo processual para reúso de água em refinaria de petróleo. / Environmental, energetic and economic analysis of a process design for water reuse in petroleum refinery.

Victor Sette Gripp 18 December 2013 (has links)
Foi construído um modelo representativo do ciclo de vida da água em uma refinaria de petróleo, contemplando todos os usos a que esta se presta. Nesse contexto foram avaliados do ponto de vista ambiental, energético e econômico cenários em que etapas adicionais eram incorporadas ao tratamento de efluentes de forma a viabilizar o reúso de água e o fechamento do circuito na própria refinaria, reduzindo assim a necessidade de captação e, consequentemente, de tratamento da água bruta captada pela refinaria. O Cenário I corresponde ao cenário-base, sem implantação de nenhuma ação voltada ao reúso. No Cenário II, é incorporada a etapa adicional chamada Tratamento Fase 1, constituída por um processo de Clarificação seguido de uma Eletrodiálise Reversa (EDR) que permite o reúso de 255,7 m3/h dos 350 m3/h lançados inicialmente ao corpo hídrico no Cenário I. No Cenário III, é incorporada ao arranjo do Cenário II uma etapa de Cristalização Evaporativa para tratar o concentrado salino da EDR, recuperando, assim, mais 55,4 m3/h dos 350 m3/h lançados inicialmente, utilizando, para isso, vapor residual inicialmente não aproveitado pela refinaria. A análise ambiental foi desenvolvida por Avaliação do Ciclo de Vida (ACV) e constatou um desempenho muito semelhante dos três cenários. Apesar disso, a análise em perfil aberto, de impactos de midpoint, evidenciou ganhos ambientais significativos associados ao fechamento de circuito de água e, embora com vantagens muito discretas, o Cenário III apresentou um desempenho superior ao do Cenário II em todas as categorias e, na grande maioria delas, também superior ao desempenho do Cenário I. A análise de indicador único, em endpoint, destacou o impacto em Mudança Climática, relativo principalmente à queima de gás natural na caldeira para a geração de vapor, como o principal impacto ambiental associado ao ciclo de vida da água na refinaria, responsável por mais de 90% do valor correspondente ao resultado do indicador único. A análise energética foi desenvolvida utilizando-se o indicador de Demanda Cumulativa de Energia (CED) e resultou em um desempenho superior do Cenário I, ainda que com pequenas diferenças em relação aos Cenários II e III. O pior desempenho foi o do Cenário II. Comparando-se a contribuição relativa dos diferentes tipos de energia, destaca-se a energia de origem hidrelétrica, responsável por cerca de 80% do indicador único de CED em todos os três cenários. A análise econômica foi realizada por meio de indicadores tradicionalmente utilizados para a análise de viabilidade de projetos Taxa Interna de Retorno (TIR) e Valor Presente Líquido (VPL) , considerando, como referência, as regras de cobrança pelo uso da água vigentes na bacia do rio Paraíba do Sul. Com os preços cobrados atualmente pelo uso da água desta bacia, a implantação de ambos os cenários de reúso (II e III) não se viabiliza economicamente. Para que isso ocorra, o valor cobrado pelo uso da água teria que ser da ordem de 50 a 80 vezes maior do que o que é cobrado atualmente. Dentre os cenários de reúso, o Cenário II apresentou desempenho econômico superior ao do Cenário III. / It was built a representative model of the water life cycle within a petroleum refinery, considering all the uses in which it is applied. In this context, under environmental, energetic and economic perspective, different scenarios were analyzed, where further treatment stages were added to the wastewater treatment process so that recycled water could be provided back to the refining process, reducing, therefore, the need for freshwater intake and pretreatment by the refinery. Scenario I is the base scenario, without implementation of any water reuse aimed action. In Scenario II, it is incorporated the additional stage called Phase 1 Treatment, which consists of a Clarification process followed by an Electrodialysis Reversal (EDR).This enables the recycling of 255.7 m3/h from the 350 m3/h previously discharged to the water body in Scenario I. In Scenario III, it is incorporated to the Scenario II setting an Evaporative Crystallization process for treating the concentrated brine resulting from the EDR process. This enables the recovery of more 55.4 m3/h from the 350 m3/h initially released, using, for that, the energy from residual steam previously not used by the refinery. The environmental analysis was developed through Life Cycle Assessment (LCA) and found very similar performances for all three scenarios. Despite that, the open profile analysis, of midpoint impacts, showed significant environmental gains from the closure of the water circuit and, though with very small advantages, Scenario III showed a better performance than Scenario II in all impact categories and, in most of them, also better than Scenario I performance. The single score analysis, considering endpoint impact categories, highlighted Climate Change, specially related to the natural gas burning in the boiler for steam generation, as the main impact category associated to the water life cycle within the refinery, being responsible for more than 90% of all the value of the single score indicator. The energetic analysis was developed using the Cumulative Energy Demand (CED) indicator and resulted in a better performance of Scenario I, even if with just small differences from Scenarios II and III. The worst performance was from Scenario II. Comparing the relative contribution of the different types of energy, the hydroelectricity was the most important one, being responsible for around 80% of the CED single score in all three scenarios. The economic analysis was developed through traditional indicators used for assessing projects viability Internal Return Rate (IRR) and Net Present Value (NPV), considering, as reference, the rules of charging for water use valid nowadays at the Paraíba do Sul river basin. With the prices charged nowadays for the water use from this basin, the implementation of both reuse scenarios is not economic viable. In order to make it viable, the charged value would have to be around 50 to 80 times higher than it is today. Among the reuse scenarios, Scenario II had a better economic performance than Scenario III.
124

Índice de geração de efluentes aplicado a uma refinaria de petróleo / Effluent generation index applied to oil refinery

Oliveira, Priscilla Mariano de 19 August 2018 (has links)
Orientador: Carlos Gomes da Nave Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-19T00:37:37Z (GMT). No. of bitstreams: 1 Oliveira_PriscillaMarianode_M.pdf: 10824605 bytes, checksum: 47b264ae4588180810a4be93864e2f1b (MD5) Previous issue date: 2010 / Resumo: Visando subsidiar a gestão ambiental das indústrias do estado de São Paulo, aperfeiçoar o planejamento e execução de suas ações, a Companhia Ambiental do Estado de São Paulo CETESB instituiu o monitoramento por indicadores ambientais envolvendo a captação de água, a geração e lançamento de efluentes versus produto principal produzido. Atendendo a estas especificações propõe-se a aplicação do Indicador de Geração de Efluente (IGE) permitindo as indústrias de refinaria de petróleo gerenciar sua emissão de efluentes em relação ao produto final produzido, o petróleo processado. Na Petrobras Refinaria de Paulínia, local de aplicação deste estudo, os sistemas de drenagens são abertos, sofrendo a influencia de precipitação, o que exigiu a aplicação de modelos de chuva-vazão para quantificar e descontar este incremento do volume de efluente real gerado. Na simulação do escoamento superficial utilizou-se do método NRCS para determinar a chuva efetiva e do método do hidrograma unitário adimensional para a obtenção dos hidrogramas relativos às áreas de diferentes usos e condições de impermeabilização, além do método da onda cinemática para a propagação na rede de canais de drenagem no âmbito da refinaria, permitindo a dedução dos volumes escoados. A partir disto, foram gerados os índices mensais de comparação entre os volumes de petróleo processado e efluente gerado pelo processo no período de um ano. Os resultados conduziram a obtenção de índices variando entre 1,0 a 2,3 % incluindo modificações na dinâmica de processo e a sazonalidade meteorológica. O IGE permite centralizar e aprimorar as informações sobre a produção de efluentes industriais em relação ao desempenho do processo da empresa, adquirindo dados e ferramentas de colaboração necessárias para enfrentar desafios na experiência na gestão de processo com foco ambiental promovendo a maximização de desempenho do seu ativo / Abstract: To subsidize the environmental management of industries in the state of Sao Paulo, improve the planning and execution of their actions, the Companhia Ambiental do Estado de São Paulo CETESB established the monitoring for environmental indicators involving water caption, the generation and release of effluent versus main product produced. Given these requirements it is proposed the application of the Effluent Generation Index (IGE) allowing industries to manage their oil refinery effluent emissions in relation to the final product produced processed oil. In the Petrobras Paulínia Refinaria REPLAN, local application of this study, the drainage systems are open, suffering the influence of precipitation, requiring the application of rainfall-runoff models to quantify and deduct this increase in the volume of effluent generated real. In the simulation of surface runoff NRCS method was used to determine effective rainfall and the dimensionless unit hydrograph method to obtain hydrographs of areas relating to different uses and conditions of waterproofing, in addition to the kinematic wave method for propagation in the network of drainage channels within the refinery, allowing the deduction of runoff volumes. From this, the monthly indices were generated to compare the volumes of oil and processed wastewater generated during the period of one year. The results led to obtain indices ranging from 1.0 to 2.3% including changes in process dynamics and the seasonal weather. The IGE allows centralize and improve the information on the production of industrial effluents in relation to the performance of the business process, acquiring data and collaboration tools needed to face challenges on experience in process management with a focus on promoting environmental maximizing performance of its assets / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
125

Fractionnement de fibres de biomasses herbacées endémiques ou cultivées dans une zone d'estuaire : Eco-conception de matériaux pour la construction / Fractionation of endemic or cultivated herbaceous biomass on estuary area : Eco-design of construction materials

Rigal, Matthieu 25 March 2015 (has links)
Le fractionnement de quatre biomasses herbacées modèles présentes ou cultivées dans l’estuaire de la Loire est étudié pour la production d’agrofibres adaptées à leur usage dans les matériaux composites écoconçus pour la construction. Les biomasses caractérisées chimiquement et physicochimiquement sont traitées par trois technologies de complexité croissante : le broyeur à marteaux permettant une fragmentation transversale et longitudinale radiale, le défibrage mécanique orientant les contraintes de façon longitudinale radiale et tangentielle, et le défibrage thermomécanique permettant un raffinage à l’échelle de la fibre élémentaire. Le Foin des Marais, modèle de mélange d’herbacées composé de tiges portant des feuilles, endémiques de prairies mésohygrophiles, est une source d'agrofibres cellulo-hémicellulosiques peu lignifiées (ratio cellulose/hémicelluloses/lignines 50/40/10) présentant un très fort taux de composés hydrosolubles (17 à 27% de MS), très hydrophiles (ratio liquide/solide à saturation L/Ssat entre 5,2 et 9,7), relativement fines (facteur de forme L/D >10) et de petites dimensions (moins de 5 cm) permettant l’obtention d’une grande gamme de densité de mats (37 à 112 kg/m3) et ayant une bonne aptitude à l’auto-assemblage sous contrainte. La Rouche, modèle de mélange d’herbacée composés de feuilles ayant des tiges, endémique de prairies hygrophiles, est une source d'agrofibres cellulo-hémicellulosiques peu lignifiées (ratio 50/40/10) présentant un fort taux de composés hydrosolubles (16% de MS), hydrophiles (L/Ssat entre 4,1 et 10,7), fournissant une large gamme de morphologie d’agrofibres allant jusqu’à 13cm de long pour des L/D de 100, formant des mats de 32 à 121 kg/m3, et ayant une bonne aptitude à l’autoassemblage. La Canne de Roseau (Phragmites australis), modèle de tiges creuses rigides, endémiques des bas marais, est une source d'agrofibres rigides beaucoup plus lignifiées (ratio 50/30/20) contenant peu de composés hydrosolubles (6 à 8% de MS), thermostables jusqu’à 220°C et relativement peu hydrophiles (L/Ssat de 3,4) si elles ne sont pas trop déstructurées, ne générant que de agrofibres courtes (moins de 5 cm) et de faible finesse (L/D <15). Les tiges de Mélilots jaune et blanc (Melilotus officinalis et Melilotus alba), dicotylédones à croissance secondaire adaptée à la culture sur les terrains de l’estuaire de la Loire, s’est avéré produire deux classes d’agrofibres. La première est composée d’agrofibres longues, extractibles du cortex de la tige, souples et essentiellement cellulosiques (ratio 75/15/10) pouvant aller jusqu’à 16cm de long (L/D>100), formant des mats de 38 à 42 kg/m3; la seconde classe d’agrofibres macroporeuses courtes et rigides extractibles du bois, beaucoup plus lignifiées (ratio 65/15/20), ayant très peu d’extractibles (2 à 3% de MS), et peu hydrophiles (L/Ssat entre 2,5 et 2,8). Un nouveau procédé d’extraction d’agrofibres longues (dm à cm) courtes (cm à mm), et ultra courtes (mm à μm) est développé. Des agrofibres sélectionnées sont mises en oeuvre avec de la colle de caséine dans des agrocomposites basse densité type blocs isolants thermiques (40 à 82 mW/m*K) et phoniques (indice d'affaiblissement sonore entre 0,18 et 1,2 dB(A)/mm) ; avec de la colle d’os dans des agrocomposites haute densité type panneaux de particules et de fibres (D jusqu’à 1,3 g/cm3, Eflexion jusqu’à 3,9 GPa et σmax flexion jusqu’à 39 MPa) ; ainsi qu’avec une matrice thermoplastique recyclable (PP+PPMA) chargées jusqu’à 40% en agrofibres et présentant une tenue mécanique jusqu’à 5 fois plus élevée en traction et en flexion. Parallèlement, les graines de Mélilots sont caractérisées, et se révèlent être riche en protéines (31 à 32% de MS) et avoir un fort potentiel en fraction extractible aqueuse (34 à 36% de MS) contenant des galactomannanes. Le raffinage de cette agroressources a été entrepris en vue de l'obtention de liants pour des agrocomposites. / The fractionation of four Loire estuary herbaceous biomasses models, endemic or cultivated, have been studied for their agrofibre production potential and adapted for their use in composite materials for ecodesigned construction. Chemically and physicochemically characterized biomasses have been processed by three increasingly complex technologies: hammer-mill that provides transversal and radial longitudinal fragmentation, mechanical defibration orienting the constraints in radial and tangential longitudinal way, and thermomechanical defibration that provides a refining at the scale of elementary fibre. Hay of Swamps, a herbaceous model made of a mix of stem bearing leaves, endemic of mésohygrophile land, is a source of few lignified cellulo-hemicellulosic agrofibres (50/40/10 ratio cellulose/hemicelluloses/lignin) with a very high rate of water-soluble compounds (17 to 27% of DM), very hydrophilic (saturation liquid/solid ratio L/Ssat between 5.2 and 9.7), relatively thin (shape factor L/D >10) and small size (less than 5 cm) allowing mats with large density range (37 to 112 kg/m3) with good self-assembling properties. Rouche, a herbaceous model made of a mix of leaves with stem, endemic of hygrophile land, is a source of little lignified cellulo-hemicellulosic agrofibres (50/40/10 ratio) with a high rate of water-soluble compounds (16% de DM), hydrophilic (L/Ssat between 4.1 et 10.7), producing a large agrofibres morphology range, up to 13cm long and L/D to 100, and allowing mats with density of 32 to 121 kg/m3, with good self-assembling properties. Reed (Phragmites australis), stiff hollow stems model, endemic of low-marsh, is a source of highly lignified stiff agrofibres (50/30/20 ratio) with a low rate of water-soluble compound (6 to 8% of DM), thermostable up to 220°C and relatively little hydrophilic (L/Ssat= 3.4) if they are not too much destructured, producing only short agrofibres (less than 5 cm) with low thinness (L/D <15). Yellow and white sweet clovers stem (Melilotus officinalis and Melilotus alba), secondary growth dicotyledon able to be cultivated on estuary land, provides two kinds of agrofibre. The first kind is stem cortex extractable long agrofibres, flexible and primarily cellulosic (75/15/10 ratio) up to 16cm long (L/D>100 and allowing light mat with density of 38 to 42 kg/m3. The second kind is secondary xylem extractable macroporous short and stiff agrofibres, highly lignified (ratio 65/15/20), with a very low rate of water-soluble compounds (2 to 3% of DM), and little hydrophilic (L/Ssat between 2.5 and 2.8). A new extraction process of long (from decimetric to centimetric length), short (from centimetric to millimetric length), and ultra-short (from millimetric to micrometric length) agrofibres had been developed. Selected agrofibres are processed with casein glue in low density agrocomposites such as insulating material (40 to 82 mW/m*K and sound reduction factor between 0.18 to 1.2 dB(A)/mm) ; with bones glue in high density agrocomposites such as particle board and fibreboard (D until 1.3 g/cm3, Eflexion until 3.9 GPa et σmax flexion until 39 MPa) ; thus with a recyclable thermoplastic matix (PP+PPMA) loaded until 40% of agrofibres, having a tensile and flexure mechanical strength almost 5 time higher. In parallel the sweet clover seeds had been characterized, and demonstrate to be rich in proteins (31 to 32% of DM) and to have a great potential in being water-extractable (34 to 36% of DM) containing, among other, galactomannans. The refining of this agroresources has been undertaken in the development of new binding materials for agrocomposites.
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Study on bioaccumulation and integrated biorefinery of vegetable oil and essential oil of Coriander (Coriandrum sativum L.) / Etude de la bioaccumulation et du bioraffinage des huiles végétale et essentielle de coriandre (Cordiandrum Sativum L.)

Nguyen, Quang Hung 24 September 2015 (has links)
Les apiaceae peuvent être définies en tant qu' Aroma-Tincto-Oleo-Crop (ATOC), plantes qui contiennent à la fois une huile végétale et une huile essentielle. Appliquer le concept d'agroraffinage aux ATOC revient à proposer un procédé séquentiel alliant une co-extraction huile végétale et huile essentielle à une valorisation des résidus en tant que source de molécules biosourcées et de susbtrat pour la formulation d'agromatériaux . Les objectifs de cette thèse seront donc d'étudier la faisabilité biologique et technologique d'application du concept d'ATOC-raffinage à la coriandre (Coriandrum sativum L.). Le chapitre I présente l'état de l'art bibliographique sur l'extraction et l'analyse des huiles végétales et huiles essentielles de coriandre tandis que dans le chapitre II sont décrits les matériels et méthodes mis en oeuvre au cours de la thèse tant au niveau échantillonnage, extraction, analyse que traitement des données. Le chapitre III est centré sur l'étude des différents paramètres biologiques pouvant influencer la bioaccumulation des huiles végétales et huiles essentielles dans la coriandre (différentes variétés, différents organes de la plante, différents stades de développement biologique) et leur impact sur l'activité anti-oxydante des extraits obtenus à partir des résidus d'extraction. Dans le chapitre IV, la technologie d'extrusion (mono-vis et bi-vis) a été appliquée aux graines de coriandre dans le but d’évaluer la faisabilité du pressage mécanique du fruit de la coriandre pour l’extraction d'une huile végétale aromatisée. L’influence des conditions expérimentales sur le rendement d'extraction en huile végétale (diamètre de buse et distance buse-vis (extrudeur mono-vis) ou configuration de vis, coefficient de remplissage et température de pressage (extrudeur bi-vis)) a été étudiée tandis que la faisabilité de la valorisation du résidu solide d'extraction en agromatériaux (thermo-pressage) a été montrée. / Apiaceae could be defined as Aroma Tincto Oleo Crops (ATOC), e.g. plants containing both vegetable oil and essential oil. Applying agroreffinery concept to ATOC led to propose a sequential fractionation process coupling co-extraction of vegetal oil and essential oil to a valorization of by-product residues as biosourced active molecules and substrates for designing agromaterials. The aim of this thesis is to determine the biological and technological feasability of application of the ATOC-refinery concept to coriander (Coriandrum sativum L.) Chapter I reports a bibliographic state of the art study on extraction and characterisation of coriander vegetal oil and essential oil while chapter II describes materials and methods setting up during the thesis for sampling, extraction, analysis and data processing. Chapter III focus on the study of major various biological parameters influencing bioaccumulation of vegetal oil and essential oil in coriander (different plant varieties, different plant organs, different biological stages) and their impact on anti-oxidant activity of extracts obtained from extraction residues. In chapter IV, coriander fruits are processed by extrusion technology (mono screw and twin-screw extruder) in order to evaluate the feasability of mechanical pressing for extracting a flavored vegetal oil. Influence of operating parameters on vegetal oil extraction yields (nozzle diameter and nozzle/screw distance (single-screw extruder) or screw configuration, device’s filling coefficient and pressing temperature (twin-screw extruder)) is studied while the feasability of valorization of extraction cake as agromaterial (thermopressing) was stated.
127

Compost bioremediation of oil sludge by using different manures under laboratory conditions

Ubani, Onyedikachi 06 1900 (has links)
This study was conducted to measure the reduction in polycyclic aromatic hydrocarbons (PAHs) content in oil sludge by co-composting the sludge with pig, cow, horse and poultry manures under laboratory conditions. Four kilograms of soil spiked with 800g of oil sludge was co-composted differently with each manure in a ratio of 2:1 (w/w) spiked soil: manure and wood-chips in a ratio of 2:1 (w/v) spiked soil: wood-chips. Control was set up similar as the one above but without manure. Mixtures were incubated for 10 months at room temperature. Compost piles were turned weekly and moisture level was maintained at between 50% and 70%. Moisture level, pH, temperature, CO2 evolution and oxygen consumption were measured monthly and the ash content at the end of experimentation. Bacteria capable of utilizing PAHs were isolated, purified and characterized by molecular techniques using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), amplification of the 16S rDNA gene using the specific primers (16S-P1 PCR and 16S-P2 PCR) and the amplicons were sequenced. Extent of reduction of PAHs was measured using automated soxhlet extractor with Dichloromethane as the extraction solvent coupled with gas chromatography/mass spectrometry (GC/MS). Temperature did not exceed 27.5OC in all compost heaps, pH ranged from 5.5 to 7.8 and CO2 evolution was highest in poultry manure at 18.78μg/dwt/day. Microbial growth and activities were enhanced. Bacteria identified were Bacillus, Arthrobacter and Staphylococcus species. Results from PAH measurements showed reduction between 77 and 99%. The results from the control experiments may be because it was invaded by fungi. Co-composting of spiked soils with animal manures enhanced the reduction in PAHs. Interestingly, all bacteria isolated and identified in this study were present in all treatments, including the control. / Environmental Sciences / M.Sc. (Environmental Sciences)
128

Bewertungsmodell für die Wertschöpfungstiefe der Erdölverarbeitung in der Mongolei

Dashdavaa, Altantsetseg 01 August 2013 (has links)
Die Forschungsarbeit beschäftigte sich mit der Frage, ob es zielführend ist, die Mongolei durch Veredelung eigener Ölressourcen mit Mineralölprodukten zu versorgen. Die Mongolei ist ein Land mit großem mineralischen Rohstoffpotential, darunter auch Erdöl. Zurzeit wird der Bedarf an Mineralölprodukten ausschließlich durch Import gedeckt. Zur Untersuchung der technischen Machbarkeit einer Ölverarbeitungsindustrie wurden verschiedene Raffinieriekonzepte auf Basis des mongolischen Rohöls Tamsag erarbeitet. Anschließend wurde anhand einer Bewertungsmethode die gesamtwirtschaftliche Relevanz der Downstream-Industrie in der Mongolei geprüft. Im Ergebnis der Untersuchungen zeigte sich, dass eine Erdölindustrie für die Mongolei sinnvoll ist. Die Erdölveredelung, als neuer Wirtschaftszweig, würde Möglichkeiten wirtschaftlicher Entwicklung eröffnen und die Importabhängigkeit der strategisch wichtigen Mineralölprodukte vermeiden.
129

Treatment Technology for VOC Emissions from Oil Refineries : Case study of measures taken to minimize VOC emissions at Swedish petrochemical companies to be appiled at Chineses Refineries

Odén, Hanna January 2010 (has links)
The aim of this thesis is to give suggestions on what measures to take to improve the VOC emission situation in refineries in Tianjin, China, through existing technologies in refineries in Sweden. This has been done by identifying the main places of leakage in oil refineries in Sweden, identifying what VOC compounds are emitted from the plants and the amounts emitted, mapping out different measures taken by oil refineries in Sweden to minimize VOC emissions, evaluating the different measures and suggesting how to move forward with VOC control in Tianjin. Six case studies have been done in Sweden; at Preemraff Lysekil, Shell refinery in Gothenburg, Berg depot Statoil Sweden situated in Nacka, Nynas refinery situated in Nynäshamn, Scandinavian Tank Storage situated in Torshamnen and Oxelösund harbor. Two case studies at Chinese refineries were made, PetroChina Dagang Petrohemical Company and China Petroleum and Chemical Corporation, Sinopec, Tianjin Branch, both situated in Tianjin Binhai New Area. Since the data retrieved from the Chinese refineries is insufficient to make a qualitative evaluation of the state of their VOC treatment it is not possible to propose measures for these two refineries. Instead this evaluation is focused on general problems and solutions at refineries and gives an idea of what can be done to improve the VOC emission situation at refineries. The report contains an evaluation of internal measures and technical solutions at Swedish refineries and other petrochemical companies. The evaluation is focused as much as possible on the Chinese situation. The technologies have been evaluated from an environmental, technical and economical point of view. This has resulted in recommendations for refineries that wish to enhance their VOC control. / Detta examensarbete har gjorts som en avslutande del i utbildningen Civilingenjör i Kemiteknik vid Kungliga Tekniska högskolan, Stockholm. Idén för arbetet introducerades av Östen Ekengren, IVL Svenska Miljöinstitutet, och har utförts vid IVL:s kontor i Stockholm. Den har handletts från Institutionen för Industriell Ekologi, KTH. Oljeraffinaderier släpper ut stora mängder VOC. På grund av den stora produktionsskalan och fabriksområdets omfattning är det svårt att veta hur mycket och vad som släpps ut. Lättflyktiga organiska ämnen (Volatile organic compounds, VOC) är organiska föreningar som har ett tillräckligt högt ångtrycker för att förångas under normala förhållanden. Stora mängder VOC läcker från oljeraffinaderier varje år. Tianjin är en industristad med stora investeringar. På grund av den stora industriella aktiviteten i området är VOC-problemen stora. En av de stora utsläppsbovarna är den petrokemiska industrin. Tianjin Academy of Environmental Science (TAES) har frågat efter Svensk teknik att minimera VOC-utsläpp från petrokemisk industri. Målet med detta examensarbete är att ge förslag på vilka åtgärder som kan tas för att förbättra VOC-utsläppssituationen i raffinaderier i Kina genom befintlig teknik på Svenska raffinaderier. Detta har gjorts genom följande steg: Identifiera de största utsläppsområdena på oljeraffinaderier i Sverige Identifiera vilka VOC-föreningar som emitteras från raffinaderierna samt i vilken mängd. Kartlägga olika åtgärder vid oljeraffinaderier i Sverige och i Tianjin, Kina för VOC-utsläpp. Utvärdera de olika åtgärderna och föreslå hur man kan gå vidare med VOC-kontroll i Kina. Sex fallstudier har genomförts i Sverige; Preemraff Lysekil, Shell raffinaderi i Göteborg, Bergs depot Statoil Sweden i Nacka, Nynas refinery i Nynäshamn, Scandinavian Tank Storage i Torshmnen och Oxelösunds hamn, Oxelösund. Två fallstudier har genomförts vid Kinesiska raffinaderier; PetroChina Dagang Petrochemical Comapany och China Petroleum and Chemical Corporation, Sinopec, Tianjin Branch, båda placerade i Tianjin Binhai New Area. Eftersom otillräcklig data från de Kinesiska raffinaderierna har gjort det svårt att göra en kvalitativ utvärdering av hur långt de kommit i VOC-arbetet har det inte varit möjligt att föreslå åtgärder för dessa två raffinaderier specifikt. Istället har utvärderingen fokuserats på generella problem och lösningar vid raffinaderier och att ge en ide om vad som kan göras för att förbättra VOC-utsläppssituationen vid raffinaderier. VOC från oljeraffinaderier med traditionell aktivitet består i huvudsak av alkaner, alkener och aromater där alkaner utgör den största delen. Alla dessa tre grupper förekommer naturligt i råolja. Vilka föreningar som förekommer i VOC-plymen från en fabriksanläggning beror på vilken råolja som används, hur processen ser ut och vilka produkter som produceras. Sammansättningen av VOC-plymen varierar därför från raffinaderi till raffinaderi. De största emissionskällorna vid raffinaderier som producerar i första hand bensin och diesel är tankparkerna, speciellt under fyllning. Tankparker som innehåller råolja utgör den största emissionspunkten vid dessa raffinaderier. Den näst största källan är processområdet. Detta medför att tankparker och processområde är de områden där störst fokus på minimering skall ligga för raffinaderier med samma typ av verksamhet. Produktionen vid Nynas Refinery kräver en annan råolja Här är det processen som utgör den största utsläppskällan tillsammans med vattenrening. Uppvärmda bitumencisterner utan rening utgör också en stor utsläppspunkt. Eftersom processområdet och tankparkerna har många potentiella läckpunkter är det primära sättet att minimera VOC-utsläpp tätning och underhåll på hela fabriksområdet. Införandet av rutiner för detta har visat sig mycket effektivt speciellt vid Shell raffinaderi. En annan idé skulle kunna vara att inkludera VOC-utsläppsmätning i on-line system för produktkvalitet. Detta skulle medföra ett inbyggt VOC-kontrollsysem. Detta har inte gjorts än men det kan vara värt att ta en närmare titt på. Kina har stort fokus på luktkontroll. Detta är bara en liten del av VOC-problemet. Metan utgör en stor del av utsläppen från råoljecisterner, vilka är vanliga luktbovar. För att eliminera lukt är adsorbtion med aktivt kol effektivt. Filtret fångar däremot inte kortare kolkedjor som metan och etan. För att eliminera dessa är förbränning den enda lösningen. Ingen luktsanerningsmetod som presenteras i denna rapport genererar någon vinst för företagen. Gasåterföringsanläggningar (VRU) har visats vara en gynnsam metod för att behandla emissioner vid tankning. En snabb överslagsräkning baserat på den återförda mängden bensin och diesel vid Preemraff Lysekil 2008 ger en vinst på 0,9 – 1,3 miljoner Euro/år. En stor andel VOC förbränns i fackla på raffinaderier. Denna gas skulle kunna användas som bränngas eller för energiåtervinning. Penningvärdet på energin i gasen som facklas är stor. Genom att installera en kompressor kan gas som skulle facklas användas som bränngas i raffinaderierna istället. Båda de studerade raffinaderierna i Kina angav fackling som den primära VOC-åtgärden. Man kan därmed anta att stora mängder gas facklas där. Detta visar att det finns mycket att tjäna på att hitta alternativa sätt att använda gasen. Flyktiga utsläpp är en stor del av VOC-källorna vid oljeraffinaderier. Utsläppunkterna beror på typ av råolja, process och produkter. Varje raffinaderi ar unikt och måste därför mäta sin a utsläpp. Vid mätning av ett helt fabriksområde med Solar Occulation Flux-metoden, som är en on-lineteknik som mäter VOC-utsläpp i from av alkaner, fås en bild av totala utsläppen från hela fabriken. Detta är till stor hjälp vid identifiering av problemområden och behandling av dessa. När VOC-behandling skall påbörjas vid ett raffinaderi rekommenderas följande: Mätning av VOC över hela raffinaderiområdetAnvända on-lineteknik, så som SOF Identifiera sammansättning av plymen genom kanisterprov etc. Läcksökning / Underhåll Om följande tekniska lösningar går att applicera vid raffinaderiet föreslås det att de prioriteras. Införa VRU-anläggning Energiåtervinning (minimerad fackling) Införa kommunicerande kärl För fortsatt arbete rekommenderas följande. Undersöka om det finns intresse och möjlighet att införa on-line VOC-konrollsystem eller on-line konstrollsystem för produktkvalitet. Är det tekniskt möjligt och ekonomiskt hållbart? För att kunna utvärdera miljöpåverkan av NMVOC från oljeraffinaderier har en studie av effekterna från emissionerna från Preemraff Lysekil och Shell Göteborg gjorts genom att använda karakteriseringsdata från databaserna CLM2001 och EDIP97. Detta resulterade i ett värde som ger hur många gånger fler de två raffinaderierna per ton satsad råolja bidrar till ozonformationspotentialen och globala uppvärmningspotentialen i förhållande till årspersonsekvivalenten (vad en normalperson bidrar med per år). Det visade sig att de bidrar med mycket mindre än årspersonsekvialenten per ton råolja, 0,03 gåner för Preemraff och 0,02 gånger för Shell. Men med antalet ton råolja som processas per år i åtanke så blir oljeraffinaderierna en stor källa till miljöpåverkan. Toxicitetsvärdena visade att Shell hade mycket större andel toxiska utsläpp än Preemraff. I förbränning, som fackling, så förbränns VOC till CO2. Detta medför att VOC har en sekundär GWP. Om hänsyn tas till detta kan man se att den totala GWP av VOC främst utgörs av den sekundära effekten genom fackling. Denna utvärdering visar att miljöpåverkan är olika för olika raffinaderier, även de med samma typ av verksamhet.
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Multiphase Flow Effects on Naphthenic Acid Corrosion of Carbon Steel

Jauseau, Nicolas January 2012 (has links)
No description available.

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