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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.
41

Estudo das variáveis de processo na produção e na purificação do biodiesel de soja via rota etílica / Study of process variable in the production and purification of soybean via rota ethyl biodiesel

Lopes, Adriana Carla de Oliveira 27 August 2008 (has links)
Biodiesel is an alternative fuel, renewable, biodegradable and no toxic. The transterification of vegetable oils or animal fat with alcohol is the most usual manner of production of that fuel. The objectives of this study were to evaluate the process of production of biodiesel in pilot scale, and carry out the study of the variables that influence the process of etanolise of soybean oil, using a catalyst basic sodium hydroxide, in order to obtain the conditions operational leading to greater conversion to biodiesel and also assess the variables that influence the process of purification of fuel. The pilot plant consists of a glass reactor with a capacity of 3 L, provided with: Jersey movement of heated water and mechanical agitation. The experiments to study the production of biodiesel from soybeans have been conducted in accordance with the planning factor fragmented. Already the study of the same purification process was conducted in accordance with a schedule full factorial. The variables studied for the production process were: temperature of reaction (30-70 oC); concentration of catalyst (0,5-1,5%), time of reaction (0,5-2 hours); speed of agitation ( 150-350 rpm), and ethanol molar ratio: soybean oil (4:1-10:1). And these variables for the purification process were: temperature (30-70 ° C) and pH (2-5) of water washing. In the study of the production of biodiesel from soybean parameter of the evaluation was to conversion into biodiesel, determined by gas chromatography, using the chromatograph VARIAN, model CP-3800, and for studying the process of purification, the parameter of response was the amount of Water spent to counteract the biodiesel from soybean. At the end of the work was verified that the variables: molar ratio oil / alcohol, the reaction temperature and concentration of the catalyst has strong influence in the production of biodiesel. And as the temperature and pH of the water for washing exercise strong influence in the soybean biodiesel purification process. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O biodiesel e um combustivel alternativo, renovavel, biodegradavel e nao toxico. A transesterificacao dos oleos vegetais ou gordura animal com alcool e a forma mais usual de producao desse combustivel. Os objetivos desse trabalho foram avaliar o processo de producao do biodiesel em escala piloto, bem como, realizar o estudo das variaveis de processo que influenciam a etanolise do oleo de soja, utilizando o hidroxido de sodio como catalisador basico, de forma a se obter as condicoes operacionais que levam a uma maior conversao em biodiesel e tambem, avaliar as variaveis de processo que influenciam na purificacao deste combustivel. A planta piloto e composta por um reator de vidro com capacidade de 3 L, provido de: camisa de circulacao de agua aquecida e agitacao mecanica. Os experimentos para o estudo da producao do biodiesel de soja foram realizados de acordo com o planejamento fatorial fracionado. Ja o estudo do processo de purificacao do mesmo foi realizado de acordo com um planejamento fatorial completo. As variaveis estudadas para o processo de producao foram: temperatura de reação (30-70 oC); concentracao de catalisador (0,5-1,5%); tempo de reacao (0,5-2 horas); velocidade de agitacao (150-350 rpm); e, razao molar etanol : oleo de soja (4:1-10:1). E as variaveis estudadas para o processo de purificacao foram: temperatura (30-70 oC) e pH da agua de lavagem (2-5). No estudo da producao de biodiesel de soja o parametro de avaliacao foi a conversao em biodiesel, determinada por cromatografia gasosa, utilizando o cromatografo VARIAN, modelo CP-3800; e para o estudo do processo de purificacao, o parametro de resposta foi a quantidade de agua gasta para neutralizar o biodiesel de soja. Ao final do trabalho foi verificado que as variaveis: razao molar oleo/alcool; temperatura da reacao e concentracao do catalisador tem forte influencia no processo de producao do biodiesel. E que a temperatura e o pH da agua de lavagem exercem forte influencia no processo de purificacao do biodiesel de soja.
42

ALTERING THE FORMATION OF TRANS FATTY ACIDS IN CONTINUOUS CULTURES THROUGH OILS AND NATURAL DIETARY SUPPLEMENTATIONS

Ishlak, Adel 01 August 2013 (has links)
superscript your words
43

Implementation of Standard and Modified Soy Oils as Substitutes for Fish Oil in Feeds for Nile Tilapia

Mulligan, Bonnie Lynn 01 May 2013 (has links)
Seafood is the number one source of essential fatty acids, particularly, long-chain polyunsaturated fatty acids (LC-PUFA) in the human diet. As global population growth eventually surpasses what the world's wild commercial stocks can provide, reliance on the aquaculture industry to expand production will continue to increase in order to meet the demands of consumers worldwide. Currently, fluctuations in supply and cost coupled with environmental sustainability and contaminant concerns have motivated the aquaculture industry to research alternative lipid sources and feeding strategies in order to reduce the reliance on marine-derived resources. For most cultured species, replacing fish oil with terrestrial plant-based lipid sources is a minor dietary modification that has little consequence on production performance. However, fish raised on these plant-based lipid alternatives contain considerably higher medium chain polyunsaturated fatty acids (MC-PUFA) and n-6 fatty acids and less beneficial LC-PUFA and n-3 fatty acids within the fillets, thus negatively impacting the nutritional value of cultured seafood to the consumer. In order to alleviate this problem, producers can employ finishing strategies to restore fillet LC-PUFA content prior to harvest. As a complement to this approach, provision of dietary saturated fatty acids (SFA) and/or monounsaturated fatty acids (MUFA) in lieu of MC-PUFA appears to maximize the retention of LC-PUFA deposition during the grow-out period and may increase deposition during finishing. Accordingly, my objectives were to 1) assess whether the SFA, MUFA, and MC-PUFA content of the alternative lipid affected LC-PUFA levels in Nile Tilapia fed reduced fish oil feeds; and 2) using the optimal alternative lipid identified in the first objective, assess increasing fish oil replacement rates in conjunction with finishing to maximize product nutritional value and minimize fish oil usage in Nile Tilapia culture. To address the first objective, I assessed production performance and tissue composition of Nile Tilapia fed diets containing fish oil or blends of fish oil and various soybean-derived alternative lipids. Quadruplicate tanks of juvenile Nile Tilapia were fed diets containing fish oil (FISH, high in LC-PUFA) or a 50:50 blend of fish oil and standard (STD-SO, high in MC-PUFA), saturated fatty acid-enriched (SFA-SO, high in SFA), low α-linolenic (LO-ALA-SO, high in MC-PUFA), or hydrogenated (HYD-SO, high in MUFA) soybean oil for 16 weeks. Partial replacement of fish oil with soybean oils did not significantly affect production performance with the exception of the HYD-SO diet which yielded significantly reduced growth efficiency in comparison with some of the experimental diets, though not the FISH control. Despite distinctly different dietary fatty acid profiles, fillet fatty acid composition was similar among fish fed the FISH, SFA-SO, and HYD-SO diets. However, feeding the STD-SO and LO-ALA-SO diets resulted in significant enrichment of less desirable MC-PUFA and n-6 fatty acids within the fillet. Fillet LC-PUFA levels were equivalent among all groups despite the 50% reduction in dietary LC-PUFA intake among fish fed the soybean oil-based feeds. Based on these results, incorporation of STD-SO, SFA-SO, or LO-ALA-SO could be used as partial replacements for fish oil in Nile Tilapia feeds without impairing production performance, though SFA-rich soybean oils appeared to be the best alternative for maintaining a more "fish oil"-associated fillet fatty acid profile. Accordingly, the SFA-enriched soybean oil was selected for further study in the second objective trial that evaluated the effects of graded levels of fish oil replacement without or without implementation of finishing periods on production performance and fillet fatty acid composition. Nile Tilapia were fed feeds containing 100% fish oil (100-FO), the previously assessed SFA-enriched soybean oil (100-SFA-SO), or blends of fish oil and SFA-enriched soybean oil (50-SFA-SO, 75-SFA-SO). Triplicate groups of fish were fed the aforementioned diets exclusively throughout the feeding trial (100-SFA-SO unfinished, 75-SFA-SO unfinished, 50-SFA-SO unfinished) or in conjunction with 4 or 8 weeks of finishing with the 100-FO feed (100-SFA-SO + 4 wks, 100-SFA-SO + 8 wks, 75-SFA-SO + 4 wks, 75-SFA-SO + 8 wks, 50-SFA-SO + 4 wks, 50-SFA-SO + 8 wks) for a total of 20 weeks. Production performance was unaffected by dietary inclusion of SFA-enriched soybean oil when fed exclusively or in combination with fish oil, though growth performance was lower than observed in the previous trial and likely confounded by behavioral interactions and frequent spawning. After 12 weeks of consuming the SFA-enriched soybean oil grow-out diets, fillet levels of n-3 LC-PUFA were not statistically different from 100-FO control levels despite different levels of dietary inclusion. However, the high dietary levels of SFA in the experimental feeds did not translate into increased fillet SFA content, suggesting selective retention of LC-PUFA at the expense of fillet SFA. Finishing for 4 or 8 weeks increased fillet n-3 LC-PUFA content in all groups, though it appears that the 50- and 75-SFA-SO diets were more successful in maintaining acceptable health promoting n-3:n-6 ratios. Based on these results, SFA-enriched soybean oil-based feeds can be used as a cost-saving measure during grow-out, and the effects of these feeds on fillet fatty acid profile can be reversed to a considerable extent in as little as 4 weeks by implementing a finishing period prior to harvest. This approach is a promising strategy for minimizing fish oil usage while maximizing product value of cultured Nile Tilapia.
44

The effects of dietary fat source and feeding duration on pig growth performance and fat quality

Stephenson, Ethan Wade January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Michael Tokach / In 3 experiments, 4,720 pigs were used to determine the effects of: 1) dietary fat and feeding duration on growth performance and fat quality in finishing pigs; or 2) a novel protease or 3) increasing levels of Zn amino acid complex (ZnAA) or ZnO on finishing pig performance. Experiment 1 tested the effects of feeding tallow, soybean oil, or a blend of the two for various feeding durations (d 0 to 42, 42 to 84, or 0 to 84). Overall, pigs fed added fat for the entire 84 d had improved G:F compared to those fed a control diet. Additionally, pigs fed additional fat for the entire study had improved ADG and G:F as well as increased d 84 BW compared to pigs fed additional fat for 42 d. Increasing the feeding duration of soybean oil lowered monounsaturated fatty acids and increased polyunsaturated fatty acid concentrations while these values remained relatively unchanged by the addition of tallow. There were feeding period by fat source interactions for fatty acid composition and iodine value for belly and backfat, but not jowl fat, indicating a longer turnover rate for jowl fat compared to belly or backfat. In Exp. 2, adding a protease to a nutrient deficient diet increased ADFI and tended to increase ADG compared to pigs fed a negative control diet. There were no differences observed in ADG, ADFI, or G:F between pigs fed a positive control diet, formulated to 90% of the pigs SID lysine requirement, and those fed a negative control diet plus the protease, which would suggest the release values attributed to the enzyme were accurate. In Exp. 3, supplementing additional Zn from either ZnAA or ZnO at 25, 50, or 75 ppm in finishing diets for commercial finishing pigs was evaluated. Overall, no differences were observed in ADFI, but a Zn source by level interaction was observed for ADG and G:F, as pigs fed increasing ZnO were observed to have similar performance, while pigs fed added levels of 25 and 50 ppm Zn from ZnAA had decreased performance compared to those fed the highest level of ZnAA.
45

Fontes de óleo na dieta e sua importância no desempenho e na imunidade de frangos de corte

Ribeiro, Sheila Cardoso [UNESP] 20 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-20Bitstream added on 2014-06-13T19:14:36Z : No. of bitstreams: 1 ribeiro_sc_me_araca.pdf: 191988 bytes, checksum: 6ae04c780c812f7133db1a6434eef76f (MD5) / Foi avaliado o efeito do uso de óleos ricos em ácidos graxos polinsaturados ômega-3 na dieta de frangos de corte sobre o desempenho e a resposta imune humoral e celular à vacinação. Foram comparadas dietas formuladas com óleo de soja (OS), linhaça (OL) ou sardinha (OP), fornecidas a 240 frangos da linhagem Cobb, divididos em 24 grupos de 10 aves cada, num arranjo experimental 3x2 (3 tipos de óleo e 2 situações vacinais) e 4 repetições. O consumo de ração, o ganho de peso e a conversão alimentar foram avaliados aos 21, 35 e 42 dias. Metade dos grupos foi vacinado contra doença de Newcastle. A produção de anticorpos, avaliada 15 dias após a vacinação pelo método de ELISA e expressa em densidade óptica a 450nm (D.O.450nm), foi maior entre as aves alimentadas com ração com OS (P<0,05). Nos grupos alimentados com OL e OP as médias de D.O.450nm não diferiram significativamente entre vacinados e não vacinados (P>0,05). A resposta linfoproliferativa das aves vacinadas foi maior independente do tipo de óleo utilizado (P<0,05). Na análise de desempenho não houve interferência da fonte de óleo ou da vacinação sobre o ganho de peso e peso vivo. Entre as aves vacinadas a pior média de conversão alimentar correspondeu à dieta com OS. Além disso, entre as aves que receberam dieta com OS, a vacinação piorou significativamente a conversão alimentar, considerando todo o período experimental (P<0,05). Já entre as aves que receberam dieta com OL ou OP, não houve diferença na conversão alimentar entre os grupos vacinados e não vacinados (P>0,05). Estes resultados demonstram que a reação maior ao desafio vacinal prejudicou o desempenho das aves alimentadas com OS. / The effect of the use of oils rich in omega-3 polyunsaturated fatty acids in the diet of broiler on performance and humoral immunity and cellular response to vaccination were evaluated. Diets were compared with soybean oil (OS), linseed (OL) or sardine (OP), supplied to 240 broiler, Cobb, divided into 24 groups of 10 birds each in a 3x2 factorial arrangement (3 types of oil and two vaccine situations) and 4 replications. Feed intake, weight gain and feed conversion were evaluated at 21, 35 and 42 days. Half of the groups were vaccinated against Newcastle disease. The production of antibodies evaluated 15 days after vaccination by ELISA and expressed as optical density at 450 nm (D.O.450nm) was higher in birds fed OS (P<0.05). In groups fed OL and OP, the mean of D.O.450nm did not differ significantly between vaccinated and unvaccinated (P>0.05). The lymphoproliferative response of vaccinated birds was higher, regardless of the type of oil used (P<0.05). In the performance analysis, there was no interference from the source of oil or of vaccination on weight gain and body weight. Among those vaccinated, the worst average feed conversion corresponded to the diet OS. Moreover, among the birds fed OS, vaccination has significantly worsened feed conversion, considering the entire experimental period (P<0.05). Among the birds fed OL or OP, there was no difference in feed conversion between vaccinated and unvaccinated groups (P>0.05). These results demonstrate that the greatest reaction to the challenge vaccine affected performance of birds fed OS.
46

Obtenção de biodiesel por transesterificação enzimática de óleo de soja com etanol empregando t-butanol como solvente / Biodisel production by enzymatic transesterification of soybean oil with ethanol using t-butanol as a solvent

Sergio Patronelli de Carvalho 28 November 2008 (has links)
Neste estudo foi investigada a alcoólise enzimática do óleo de soja com etanol, utilizando t-butanol como solvente e enzimas imobilizadas Lipozyme TL IM, Lipozyme RM IM e Novozym 435 como catalisadores. As reações foram realizadas em um reator batelada fechado acoplado a um condensador e com constante agitação. Foram avaliadas a influência do t-butanol, do tipo de enzima utilizada, da razão molar álcool/óleo e da temperatura no rendimento em biodiesel. A etanólise do óleo de soja por sucessivas adições de álcool foi investigada e as melhores condições foram obtidas em presença de t-butanol, razão molar etanol/óleo igual a 3, temperatura de 50C e 5% (m/m) de Novozym 435. Nas reações conduzidas em presença de t-butanol não foram observadas diferenças significativas entre a adição direta e a escalonada do álcool. Os efeitos da adição de álcool só foram observados na ausência de t-butanol. O rendimento máximo em ésteres etílicos atingido foi cerca de 66% após 4h de reação com Novozym 435 na presença de solvente. / In this research, the enzymatic alcoholysis of soybean oil was investigated by using commercial immobilized lipases: Lipozyme TL IM, Lipozyme RM IM and Novozym 435 as catalysts. The reactions were carried out in a closed batch reactor with constant stirring and coupled with condenser. The influence of t-butanol, type of enzyme, molar ratio (alcohol/soybean oil) and temperature on biodiesel yield were evaluated. The ethanolysis of soybean oil by stepwise additions of ethanol was also investigated. The best conditions were obtained in t-butanol presence with ethanol/oil molar ratio of 3, temperature of 50oC and 5 wt.% Novozym 435. For the reactions carried out with t-butanol, the effects of stepwise alcohol addition were not observed, but it was realized in t-butanol absence. The maximum biodiesel yield achieved was 66% after 4h of reaction with Novozym 435 in t-butanol system.
47

Modelagem e analise do processo de obtenção do oleo de soja

Paraiso, Paulo Roberto 09 October 2001 (has links)
Orientador: Roger Josef Zem / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2017-06-20T18:15:28Z (GMT). No. of bitstreams: 1 Paraiso_PauloRoberto_D.pdf: 6072802 bytes, checksum: 03f1ff005f8e2f1bf228c5bf272314e3 (MD5) Previous issue date: 2001 / Resumo: A indústria de obtenção de óleo e fareIo de soja é um importante ramo da agroindústria da região noroeste do estado do Paraná. Os produtos gerados atendem tanto o mercado interno como o mercado externo. A concorrência é elevada, e para serem competitivos, a redução de custos e de desperdício é fundamental; além disso, como as indústrias da região utilizam o hexano como solvente na extração do óleo, a preocupação com a saúde do trabalhador e com o meio ambiente é de fundamental importância. Estas preocupações podem ser avaliadas tanto no projeto de novas unidades como no funcionamento das atuais unidades em melhores condições. Tais avaliações do processo podem propiciar uma redução no consumo de energia, bem como no consumo e no nível de perdas do hexano para o meio ambiente. O objetivo geral deste trabalho é desenvolver modelos para análise das operações existentes na obtenção do óleo bruto de soja visando a recuperação máxima de hexano e o consumo mínimo de energia. Os modelos são desenvolvidos, em regime estacionário, para analisar as condições de operação do extrator, do evaporador, do stripper e do dessolventizador-tostador (DT); na seqüência, os dados obtidos pelos modelos serão utilizados na análise energética do sistema. O modelo do extrato r se compõe de balanços de massa, relações de equilíbrio, equações empíricas e de um algoritmo de solução. O modelo do evaporador é baseado em balanços de massa, balanços de energia, relações de equilíbrio e num algoritmo de solução. Os modelos do stripper e do DT se compõem de balanços de massa, balanços de energia, relações de equilíbrio e do algoritmo de Bumingham-Otto para a solução. Desenvolvidos os modelos, as aplicações foram realizadas com dados de uma indústria local e os resultados obtidos foram bastante satisfatórios. Com isso, verifica-se que os modelos apresentados no trabalho são coerentes e poderão ser utilizados na melhoria do desempenho de uma planta de obtenção de óleo e fareIo de soja. Uma utilização importante desses modelos é no que se refere à integração energética da planta. Esta integração foi realizada com dados gerados pelos modelos e os resultados obtidos mostraram que o sistema atual da empresa já está razoavelmente integrado, mas que pequenas melhorias no consumo de energia ainda poderão ser obtidas / Abstract: The industry of oil production and soy meal is an important branch of the agroindustry of the northwest area of the Paraná State. The generated products assist both the internal market and the external market. The competition is intense, and to be competitive, the reduction of costs and of waste is fundamental; besides, as the industries of the area use hexane as solvent in the extraction of the oil, the concern with the worker's health and with the environment is of fundamental importance. These concerns can be so much appraised in the project of new units as in the operation of the current units in better conditions. Such evaluations ofthe process can propitiate a reduction in the consumption of energy, as well as in the consumption and in the level of losses of hexane to the environment. The general objective of this work is to present a methodology for analysis of the existent operations in the obtaining of the crude oil of soybean seeking the maximum recovery ofhexane and the minimum consumption of energy. The models are developed, in stationary regime, to analyze the conditions of operation of the extractor, of the evaporator, of the stripper and of the desolventizer-toaster (DT); in the sequence, the results obtained with these models wiIl be used in the analysis energy ofthe system. The model of the extractor is composed of mass balance, balance relationships, empirical equations and of a solution algorithm. The model of the evaporator is based on mass balances, balances of energy, equilibrium relationships and on a solution algorithm. The models of the stripper and of DT are composed of mass balances, balances of energy, equilibrium relationships and of Burmingham-Otto's algorithm for the solution. Once the models were developed, the applications were accomplished with data from a local industry and the obtained results were quite satisfactory. Whereupon, it is verified that the models presented in the work are coherent and they can be used in the improvement ofthe performance of a plant of oil production and soy meal. An important use of those models is in what it refers to the energy integration ofthe plant. This integration was accomplished with data from these models and the obtained results showed that the current system of the company is already quite integrated, but a small improvement in the consumption of energy can still be obtained. / Doutorado / Sistemas de Processos Quimicos e Informatica / Doutor em Engenharia Quimica
48

Degomagem de miscela de oleo bruto de soja utilizando membranas de ultrafiltração sob diversas condições de pressão e velocidade / Soybeans crude oil miscella degumming utilizing ceramic membranes: transmembrane pressure and velocity effects

Carvalho, Celio Cordeiro de 28 February 2007 (has links)
Orientador: Luiz Antonio Viotto, Lireny Aparecida Guaraldo Gonçalves / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T12:01:16Z (GMT). No. of bitstreams: 1 Carvalho_CelioCordeirode_M.pdf: 881544 bytes, checksum: 6c45ab4e5ad2c564b48dc42ad6d29cb8 (MD5) Previous issue date: 2007 / Resumo: O processo tradicional de degomagem remove principalmente os fosfolipídios presentes no óleo bruto de soja por hidratação e precipitação, seguida de agitação e separação por centrifugação. A remoção de fosfolipídios utilizando a separação por membranas é um processo que tem recebido muita atenção por parte de vários pesquisadores, por resultar em óleos de melhor qualidade com economia de energia e redução nos custos com tratamento de efluentes. O objetivo deste trabalho foi estudar a degomagem de óleo bruto de soja em miscela (4,6 kg de óleo bruto e 9,9 kg de hexano) utilizando uma unidade piloto de ultrafiltração com membranas cerâmicas de alumina com diâmetro médio de poro de 0,01 ?m de 19 e de 37 canais e de 0,05 ?m de 19 canais. Analisou-se a influência da pressão transmembrana (0,6 a 3,3 bar) e da velocidade tangencial (1,7 a 5,6 m/s) sobre o fluxo de permeado e o coeficiente de retenção de fósforo no óleo degomado. Verificou-se que para membranas de 0,01 ?m de 19 e 37 canais, pressões acima de 2,0 bar levaram a fluxos de até 70,9 kg/m2h e coeficiente de retenção de fósforo até 99,8% correspondente ao teor de fósforo no óleo degomado de 12,3 mg/kg dentro da especificação da indústria de refino. A degomagem com a membrana de 0,05 ?m realizada a 0,6 bar apresentou alto fluxo de permeado (até 133,93 kg/m2h), porém com óleo permeado com maior teor de fósforo para os padrões da indústria de refino. Também observou-se que as membranas com diâmetro médio de poro 0,01 ?m operando a baixas pressões (< 1,0 bar), independentemente das velocidades utilizadas apresentaram fluxos de até 38,53 kg/m2h e coeficiente de retenção de 98,5 %. Notou-se que o teor de fósforo no permeado aumentou com a redução da pressão transmembrana devido a menor compactação da camada gel polarizada e menor retenção de fosfolipídios e que o efeito da velocidade tangencial foi maior para a faixa de pressões mais alta / Abstract: The traditional degumming process removes mainly the phospholipids presents in the crude soybean oil by the precipitation and hydration, followed by agitation and separation by centrifugation. The removal of phospholipids using membranes separation is a process that has received much attention on the part from some researchers for presenting oils of better quality with energy economy and costs reduction with treatment of effluent. The objective of this work was to study the degumming of crude soybean oil micelle (4,6 kg of oil and 9,9 kg of hexane) using a unit pilot of ultrafiltration with alumina ceramic membranes of 0.01 μm pore diameter of 19 and 37 channels and 0.05 μm pore diameter of 19 channels. It was analyzed the transmembrane pressure influence (0,6 and 3,3 bar) and the tangential velocity on the flux and phosphorous retention in the degummed oil. It was verified that for 0.01μm pore diameter membranes of 19 and 37 channels, pressures above 2.0 bar had taken the flux up to 70.9 kg/m2h and phosphorous retention up to 99,8% correspondent to the phosphorous content in the degummed oil of 12,3 mg/kg insides the specification of the refining industry. The degumming with the membrane of 0.05 μm pore diameter presented high permeated flux (up to 133,93 kg/m2h), however with permeated oil with raised level of phosphorous for the standards of the refining industry. Also it was observed that the membranes with diameter of pore 0.01 μm operating in low pressures (< 1.0 bar), independently of the used velocity had presented flux up to 38.53 kg/m2h and retention of 98,5%. It noticed itself that the level of phosphorous in the permeated increase with the reduction of the transmembrane pressure due to of the lesser compacting of the polarization layer and the lesser retention of phospholipids, and that the effect of the tangential velocity was bigger in the higher pressures zone / Mestrado / Mestre em Tecnologia de Alimentos
49

Desacidificação de oleo de soja por extração liquido-liquido / Deacidificationof soybean oil by liquid-liquid extraction

Sa, Leticia Andrade de 03 December 2007 (has links)
Orientador: Antonio Jose de Almeida Meirelles, Christianne Elisabete da Costa Rodrigues / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T12:11:40Z (GMT). No. of bitstreams: 1 Sa_LeticiaAndradede_M.pdf: 1111674 bytes, checksum: 4740d77e5f31018175a3214d8d9ef4da (MD5) Previous issue date: 2007 / Resumo: O processo de desacidificação do óleo de soja por extração líquido-líquido (ELL) foi estudado em uma coluna de discos rotativos perfurados (PRDC), operada de modo contínuo e contra-corrente. Foram estudados sistemas-modelo formados por óleo de soja refinado com adição artificial de aproximadamente 2% de ácido linoléico comercial. Até o momento, os estudos de desacidificação de óleos vegetais por ELL realizados no Laboratório de Extração, Termodinâmica Aplicada e Equilíbrio (ExTrAE) haviam sido feitos com óleos que apresentavam teores mais altos de acidez (3 a 8%). O diferencial deste trabalho está no fato de o óleo de soja bruto apresentar baixa acidez (cerca de 2%). Outro diferencial foi a utilização de temperatura superior (50 °C) à ambiente e teor mais elevado de água no solvente, permitindo diminuir a perda de óleo neutro sem uma diminuição significativa da capacidade de o solvente extrair os ácidos graxos livres. Os experimentos foram analisados por metodologia de superfície de resposta, que permitiu avaliar a influência do teor de água no etanol (0 a 12% em massa) e da velocidade de rotação dos discos (50 a 150 rpm) na transferência de acidez e na perda de óleo neutro. Os resultados experimentais mostraram que é possível obter um óleo refinado com teor de acidez abaixo do exigido pela legislação (< 0,3%) quando se utiliza etanol anidro. Entretanto, para se atingir este objetivo utilizando altos teores de água no solvente, deve-se aumentar a altura da região de extração da coluna para transferir maior quantidade de ácidos graxos livres e para que a perda de óleo neutro seja no máximo 3%, inferior ao valor das perdas relatadas na literatura para o refino químico / Abstract: The deacidification process of soybean oil by continuous liquid-liquid extraction (LLE) was evaluated in a perforated rotating discs contactor column (PRDC). It were studied model-systems formed by refined soybean oil with artificial addition of approximately 2% of commercial linoleic acid. Until the moment, the studies of vegetable oils deacidification by LLE accomplished in the Laboratory of Extraction, Applied Thermodynamic and Equilibrium (ExTrAE) had been carried out with oils that presented higher acidity (3 to 8%). The differential of this work is in the fact that the crude soybean oil has low acidity level. Another differential was the use of a temperature (50 °C) higher than the environment and higher water contents in the solvent, allowing to reduce the loss of neutral oil without a significant reduction of the capacity of the solvent to extract the free fatty acids. The experiments were analyzed by response surface methodology, that allowed to evaluate the influence of the water in the ethanol (0 to 12% in mass) and the rotating speed of the discs (50 to 150 rpm) in the acidity transfer and on the loss of neutral oil. The experimental results showed that it is possible to obtain a refined oil with low acidity, below the required by legislation (< 0.3%) when anhydrous ethanol is used. However to reach this objective using high contents of water in the solvent, the height of the extraction region of the column must be increased to transfer greater to amount of free fatty acids and so that the loss of neutral oil is low (maximum 3%), less than the value of losses related in literature for the chemical refining / Mestrado / Mestre em Engenharia de Alimentos
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Sistemas de extração liquido-liquido para processos de purificação de biodiesel / System of liquid extraction folr biodiesel purification process

Ardila, Yurany Camacho, 1985- 12 November 2009 (has links)
Orientador: Maria Regina Wolf Maciel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-14T23:37:55Z (GMT). No. of bitstreams: 1 Ardila_YuranyCamacho_M.pdf: 2250925 bytes, checksum: 064d7ee71f7d0822b8434eb1a5680fca (MD5) Previous issue date: 2009 / Resumo: O biodiesel pode ser definido como sendo um monoalquil éster de ácidos graxos derivado de fontes renováveis, como óleos vegetais e gorduras animais, obtidos através do processo de transesterificação. Alem dos ésteres, a corrente de saída do reator de transesterificação contém a glicerina (subproduto da reação), excesso de álcool, água e poucas quantidades do catalisador. De acordo com o grau de solubilidade destes compostos, pode-se ter como efeito que quantidades consideráveis de ésteres (biodiesel) fiquem na fase rica em glicerina e que a fase rica em ésteres contenha uma importante quantidade de impurezas. Devido a este comportamento torna-se necessário entender os equilíbrios de fases líquido - líquido formados com as misturas envolvidas para poder proceder com a purificação do biodiesel. Tais dados não são encontrados na literatura atualmente, assim, inviabilizam o real entendimento da separação de fases bem como a construção de plantas virtuais e a realização de simulações computacionais. Sendo assim, o principal objetivo desta dissertação foi determinar dados de equilíbrio líquido-líquido (ELL) para sistemas ternários do tipo: BIOS + etanol + glicerina, BIOM + etanol + glicerina, BIOS + etanol + água, BIOM + etanol + água, BIOS + glicerina + água, BIOM + glicerina + água e sistemas quaternários envolvendo o catalisador NaOH usando 1% de concentração. Os termos BIOM e BIOS significam biodiesel de mamona e biodiesel de soja. Inicialmente foi feita uma caracterização físico-química dos óleos de soja e mamona visando criar as melhores condições para a efetivação da reação de transesterificação. O biodiesel foi produzido pela transesterificação etílica e, posteriormente, levado para caracterização (com o intuito de conhecer sua pureza, pois é uma propriedade importante para o uso nos experimentos realizados.). O estudo da temperatura do ELL foi feita através de curvas binodais usando o método da determinação do ponto de turbidez, encontrando que a melhor temperatura para a análise de equilíbrio foi de 25 °C. Os experimentos para a construção das linhas de amarração foram realizados em células de equilíbrio, mantendo a temperatura do sistema constante a 25 °C e pressão atmosférica. Através do planejamento fatorial 22, foi determinado o tempo de agitação (03 h) e de repouso (12 h), na faixa experimental estudada, para atingir o equilíbrio. Foi desenvolvida uma metodologia por cromatografia gasosa com detector FID (CG-FID) para a quantificação do biodiesel, etanol e glicerina usando como solvente para as analises cromatográficas o metanol. A água foi analisada por titulação Karl Fischer e o catalisador por titulação potenciométrica. Assim, foram determinadas as concentrações de cada componente nas fases rica em biodiesel, rica em glicerina/água. Posteriormente, usando o simulador comercial Aspen Plus 2006, os dados experimentais foram correlacionados através dos modelos moleculares NRTL, UNIQUAC e NRTL Eletrolitico para o cálculo do coeficiente de atividade de cada componente na fase líquida, com estimativa de novos parâmetros de interação energética. Os resultados foram considerados satisfatórios, observando-se que o modelo NRTL foi capaz de representar melhor os dados de equilíbrio dos sistemas estudados. / Abstract: Biodiesel can be defined as the mono alkyl esters of fatty acids derived from vegetable oils or animal fats, obtained through transesterification process. Besides the esters, the outlet stream of the transesterification reactor contains glycerin (a by-product of the reaction), excess alcohol, water, and small amounts of the catalyst. According to the solubility of these compounds, can have the effect that considerable amounts of esters (biodiesel) remains in the glycerin-rich phase and the ester-rich phase contains a significant amount of impurities. Because of this behavior is it necessary to understand the liquid-liquid phase equilibrium formed with the mixtures involved in order to proceed with the purification of biodiesel. Such data are not currently found in the literature, thus impracticable the real understanding of phase separation and the construction of virtual plants and the computer simulations executions. Therefore, the main objective of this work was to determine liquid-liquid equilibrium (LLE) data for the systems: BIOS + ethanol + glycerin, BIOM + ethanol + glycerin, BIOS + ethanol + water, BIOM + ethanol + water, BIOS + glycerin + water, BIOM + glycerin + water and quaternary systems involving the NaOH catalyst using 1% concentration. The terms BIOM and BIOS mean biodiesel from castor oil and soybean biodiesel. Initially, was made a physicolchemical characterization of soybean and castor oil with the aim to create the best conditions for the realization of the transesterification reactions. Biodiesel is produced by ethylic transesterification, and taken to subsequently characterization (to know its purity, because it is an important property for use in experiments performed). The study of the temperature of LLE was made by binodal curves using the method of determining the turbidity point, finding that the best temperature for the equilibrium analysis was 25 °C. The experiments for the construction of the ties lines were carried out in equilibrium cells, maintaining the system temperature constant at 25 °C and atmospheric pressure. Through factorial design 22, the agitation time (03 h) and rest time (12 h) were determined, in the experimental range studied, to reach the equilibrium. A methodology was developed by gas chromatography with FID detector (GC-FID) for biodiesel, ethanol and glycerin quantification, using methanol as solvent for GC analysis. The water was analyzed by Karl Fischer titration and the catalyst by potentiometric titration. Therefore, were determined the concentrations of each component at biodiesel - rich phases and glycerine / water - rich phase. Later, using the commercial simulator Aspen Plus 2006, the experimental data were correlated through the molecular models NRTL, UNIQUAC and Electrolytic NRTL for the calculation of the activity coefficient of each component in the liquid phase, with estimation of new parameters of interaction energy. The results were considered satisfactory, observing that NRTL was capable to represent better the equilibrium data of the studied systems. / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química

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