O objetivo deste trabalho foi desenvolver um processo efetivo de síntese enzimática de biodiesel em reator de leito fixo, conectados em série, a partir de óleos vegetais operando em modo contínuo. Para o desenvolvimento do projeto, foram selecionados óleos vegetais de baixo impacto na cadeia alimentícia, tais como óleos de babaçu, macaúba e coco que apresentam composição predominantemente láurica (35-47%). A enzima selecionada para condução dos experimentos foi a lipase microbiana de Burkholderia cepacia imobilizada covalentemente em matriz híbrida sílica-PVA com comprovada eficiência na síntese de biodiesel a partir de diferentes matérias-primas lipídicas. Todos os experimentos foram efetuados na ausência de solventes a 50?C utilizando etanol como doador do grupo acila. Foram testados reatores de leito fixo (um estágio) e em série (dois estágios). A etapa inicial do trabalho consistiu em testes de desempenho do reator (um estágio) verificando a influência das propriedades dos óleos vegetais no rendimento do processo e atividade do biocatalisador. Apesar do biocatalisador ter apresentado elevado tempo de meia- vida > 373 h, nas condições testadas, independente do óleo usado a concentração máxima de ésteres esperada não foi alcançada (68,2%) limitando os rendimentos para valores máximos de 87,5%. Para contornar as restrições identificadas foi adotada uma configuração de reator de leito fixo dois estágios incorporando uma coluna recheada com resina catiônica (Lewatit GF 202) para adsorção do glicerol formado como subproduto. O desempenho do reator foi avaliado para substratos constituídos de óleos láuricos na razão molar óleo: etanol de 1:12, definindo os limites de operação em termos de vazão do substrato. Foi quantificado o desempenho do sistema para 4 diferentes vazões volumétricas correspondendo a tempos espaciais entre 7 a 17h e determinadas para cada condição a influência do tempo espacial na concentração de ésteres de etila formados, rendimentos de transesterificação e produtividade. O funcionamento do sistema foi comprovado quantitativamente para tempos espaciais no reator de 14h, fornecendo rendimentos de transesterificação médios de 95,9 ± 4,1% e valores médios de produtividade de 41,5 ± 1,5 mg.g-1.h-1. As amostras de biodiesel purificadas apresentaram viscosidade cinemática média de 5,5 ± 0,3 mm2.s-1, valor que atende a norma americana ASTM (D6751) e a brasileira pela resolução ANP n°14/2012. A lipase imobilizada em SiO2-PVA foi estável quanto à suas características morfológicas e catalíticas revelando tempo médio de meia-vida (t1/2) superior a 500 h. O emprego da configuração de reatores de leito fixo (PBR) em duplo estágio pode elevar os níveis de rendimento de transesterificação, aumentar a produtividade de biodiesel, por consequência reduzir o custo global do processo. As características globais do desempenho do sistema contínuo proposto torna atrativa a continuidade dos estudos em escala ampliada de processo. / The aim of this study was to develop an effective enzymatic continuous process to obtain biodiesel from vegetable oils in two-stage packed bed reactors. For this, non- edible vegetable oils (babassu, macaw palm and coconut) having predominant lauric acid (35-47%) composition were assessed. The selected enzyme was the microbial lipase from Burkholderia cepacia covalent immobilized on hybrid matrix silica-PVA (SiO2-PVA) which showed already satisfactory performance in the biodiesel synthesis from different lipid feedstocks. All experiments were carried out in solvent free system at 50°C using ethanol as acyl acceptor. Packed bed reactors (simple and two-stages) were tested. Preliminary work was focused on the determination of the influence of the properties of the vegetable oils on the process yield and biocatalyst activity using simple packed bed reactor. Under the conditions used, the biocatalyst was found to have high half-life time > 373 h and independent of the used oil the maximum concentration expected esters was not reached (68.2%) limiting the maximum yield to 87.5%. To overcome such constraints a two-stage packed bed reactor incorporating a column with cationic resins (Lewatit GF 202) to remove the glycerol formed as by-product was proposed. The reactor performance was evaluated for substrates consisting of lauric oils at molar ratio of oil-to-ethanol of 1:12, determining its operation limits in terms of substrate flow rate. The system performance was quantified for four different flow rates corresponded to spatial times from 7 to 17 h. For each condition, the influence of spatial times in the ethyl esters formation, transesterification yields and productivities were determined. The reactor operation was demonstrated for spatial time of 14 h, attaining transesterification yields of 95.9 ? 4.1% and productivities of 41.5 ? 1.5 mg.g-1.h-1.The immobilized lipase on SiO2-PVA was found to be stable regarding its morphological and catalytic characteristics, showing half-life time (t1/2) higher than 500 h. Biodiesel purified samples showed average kinematic viscosity of 5.5 ± 0.3 mm2.s-1, value that meets the criteria established by the American National Standard ASTM (D6751) and Brazilian ANP resolution No. 14/2012. Therefore, the continuous packed-bed reactor connected in series and glycerol separation system has a great potential for achieving high level of transesterification yields, raising biodiesel productivity, consequently decreasing industrial process cost. The performance characteristics of the proposed continuous system made attractive to develop further studies aiming at scaling up the process.

Salmonella, a common food pathogen, costs more than any other pathogen in the United States in terms of health care costs and loss of work due to the illnesses it causes. Low-moisture foods, especially flour, are susceptible to being contaminated by Salmonella. Food producers want flour to be pathogen-free but to also retain the same functionality of non-treated flour. Heat treatment is the most common method employed for lowering the concentration of pathogens in food. However, heating can result in the loss of the flour’s functionality. Pantoea dispersa strain JFS has been isolated from flour as a nonpathogenic bacterial surrogate that closely matches the D-value of Salmonella in flour. Flour samples were subjected to dry heat (70, 75, and 80°C) and heat tolerance was determined by plating out at least four different time points for each temperature. The death rate of P. dispersa strain JFS was similar to (p<0.05) Salmonella. This strain of P. dispersa was then used as a surrogate for Salmonella in a continuous and batch heat treatment processes to determine the amount of kill achieved by each. The continuous process was conducted using varying levels of four independent variables: temperature, residence time, use of steam, and manipulation of initial water content. All 15 runs resulted in a reduction of at least 1.5 logs of the surrogate, with the greatest reduction being 2.5 logs. The batch process was conducted using one independent variable, temperature. All runs for the batch process resulted in a reduction of at least 2.5 logs of the surrogate, with the greatest reduction being 4.3 logs at 170°F. Both processes could be used to reduce any Salmonella present in flour.

Quality management (QM) is a holistic management philosophy that emphasises the involvement of every employee at different levels of an organization to achieve customer satisfaction and improve organizational effectiveness through continuous process improvement. There has been a rising interest among service sector professionals in examining the applicability and usefulness of quality management methods in service organisations. Many service organisations that have implemented quality management has achieved substantial benefits, but it is clear that implementation initiatives in some organisations have failed to live up to expectations. These mixed results point to a need to identify the factors that lie behind the success and failures of quality management programs. Empirical research in this area is extremely limited. The results of the study point to the importance of the role of employee support and encouragement of departmental co-operation for the successful implementation of quality management programs. These factors were found to be important not only initially, but also throughout the whole implementation period of QM programs. Another interesting finding is the relationship between QM success and implementation issues concerning internal organisational communication, corporate cultural change, and internal marketing. Significant differences exist in the way that each of these factors are practised and emphasised across organisations. Respondents rated the way in which they drew upon the culture, communication pattern and other behaviour to promote QM within the organisation. They also rated how important they thought these various activities were. It was found when these factors were emphasised in QM programs the chance of successful implementation was increased. Implications for quality management professionals and suggestions for further research are discussed / Doctor of Philosophy (PhD)

Hydrogenation of nitrile butadiene rubber (NBR) has been carried out industrially for a number of years, producing a material with exceptional resilience to high temperatures and oxidative conditions. Current processes involve a batch reactor which is difficult to optimize further for larger scale production. A continuous process for this particular process is required in order to provide a large volume of production with consistent qualities. The integration of heat balance could be realized in a continuous process. A novel continuous process for hydrogenation of NBR has been developed in the present work. A multistage agitated contactor (MAC) was proposed as a gas liquid reactor for this process. Comprehensive hydrodynamic data have been acquired under various process conditions. The hydrodynamic behaviour under different operating variables such as stirring speed, liquid flow rate and gas flow rate has been understood through experimental study. It is found that an increase in stirring speed intensifies liquid backmixing while an increase liquid flow rate decreases liquid backmixing. The presence of gas flow helps in reducing liquid back mixing by two coupled effects: liquid entrainment effect due to a cocurrent operation manner and a strengthening effect of liquid flow rate due to its reduction of liquid hold-up. Contradictory conclusions regarding the effect of liquid viscosity on liquid backmixing in a MAC have been resolved through experimental investigation and computational fluid dynamics (CFD) simulations. It is shown that an increase in liquid velocity dampens turbulence which contributes to liquid phase backmixing within the reactor. The established hydrodynamic understanding of MACs in the present work widens its potential application for gas liquid process. Based on comprehensive understanding of the proposed reactor, a bench-scale prototype was designed and constructed in order to demonstrate hydrogenation performance. One more efficient catalyst for NBR hydrogenation, an osmium-based catalyst, was used in the present work. Hydrogenation degree of NBR in the continuous unit was investigated at operating conditions relevant to industrial applications. It is indicated from the experimental results that a desired hydrogenation degree of over 95% in 2.5% and 5% NBR solutions can be achieved at the conditions investigated. It is also shown that both system pressure and catalyst loading increase hydrogenation conversion. Mathematical modeling of the designed process was established by coupling the intrinsic catalytic hydrogenation from batch studies and flow behavior of the reactor. A cascade of stirred tanks with back flow (CTB) model was used to characterize the dynamic hydrogenation performance in a MAC. The comparison of experimental results and numerical prediction indicates that the established model could satisfactorily predict the hydrogenation in the designed process with consideration of approximately 30%-50% catalyst deactivated due to impurities and oxygen contamination in the polymer solution. A revised n CSTRs-in-series model was proposed to predict the hydrogenation degree at steady state and a good agreement was found when comparing the predicted results with the experimental data. A continuous process for hydrogenation at a pilot scale was designed based on the primary results from the bench scale process. A process with a capacity of 50 tons/year was targeted and the hydrogenation efficiency provided by the pilot scale unit has been estimated through the established reactor model.

Orientador: Adilson Marques Gennari / Banca: Felipe Luiz Gomes e Silva / Banca: José Walter Canoas / Resumo: A organização do trabalho na indústria automática de vidro é diretamente influenciada pela tecnologia inserida no processo produtivo. Neste ramo, uma cadeia integrada de autômatas realiza as operações físico-químicas que dão corpo ao produto final. Assim, o trabalhador não se envolve diretamente na fabricação e/ou montagem, ficando apenas como supervisor do processo. Isto implica uma série de características importantes à indústria automática vidreira: não só o processo de trabalho em si é marcado por tal nuance tecnológica como também - e conjuntamente com aquele - os processos de gestão e organização da empresa como um todo. Ao tratar da relação entre tecnologia e processo produtivo, não podemos deixar de analisar a própria relação capital/trabalho em sua dinâmica histórica. Por isso, o presente estudo se volta para uma análise crítica, com viés marxista, das principais formas de gerência do trabalho surgidas ao longo da história do capitalismo. Primeiramente, destacamos as vicissitudes da divisão do trabalho na manufatura, considerando o processo de subsunção formal à subsunção real do trabalho ao capital, ou seja, estudamos como ocorre a inserção da maquinaria no processo produtivo. Em seguida, analisamos o taylorismo e o fordismo - bem como o conceito de racionalização - como mecanismos de controle do trabalho operário. Por fim, investigamos a indústria de processo contínuo - ramo no qual se insere a indústria automática de vidro -, contrapondo-a com as características das indústrias tayloristas e fordistas / Abstract: The organization of work in the auto glass industry is directly influenced by technology inserted in the production process. In this business, an integrated chain of automata performs the physical-chemical operations that embody the final product. Thus, the worker does not get directly involved in manufacturing and/or assembly, being only a supervisor of the process. This implies a number of important features to the auto glass industry: not only the work process itself is marked by such technological nuance but also - and along with that - the processes of management and organization of the company as a whole. In addressing the relationship between technology and production process, we must search capital / labor relation in its historical dynamic. Therefore, this study turns to a critical analysis, biased Marxist, of the main ways of management work that emerged throughout the historyof capitalism. First, we highlight the vicissitudes of division of labor in manufacturing, considering the process of formal subsumption to real subsumption of labor to capital, ie, we study how the inclusion of machinery occurs in the production process. We then analyze Taylorism and Fordism - as well as the concept of rationalization - as mechanisms of control of labor worker. Finally, we investigate the continuous process industry - in which sector the auto glass industry is inserted - contrasting it with the characteristics of Taylorist and Fordist industries / Mestre

Made available in DSpace on 2014-06-11T19:24:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-02Bitstream added on 2014-06-13T20:12:23Z : No. of bitstreams: 1 souza_hpb_me_arafcl.pdf: 1077752 bytes, checksum: c974ff2d0de227542f988e8097aa9a5e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A organização do trabalho na indústria automática de vidro é diretamente influenciada pela tecnologia inserida no processo produtivo. Neste ramo, uma cadeia integrada de autômatas realiza as operações físico-químicas que dão corpo ao produto final. Assim, o trabalhador não se envolve diretamente na fabricação e/ou montagem, ficando apenas como supervisor do processo. Isto implica uma série de características importantes à indústria automática vidreira: não só o processo de trabalho em si é marcado por tal nuance tecnológica como também – e conjuntamente com aquele – os processos de gestão e organização da empresa como um todo. Ao tratar da relação entre tecnologia e processo produtivo, não podemos deixar de analisar a própria relação capital/trabalho em sua dinâmica histórica. Por isso, o presente estudo se volta para uma análise crítica, com viés marxista, das principais formas de gerência do trabalho surgidas ao longo da história do capitalismo. Primeiramente, destacamos as vicissitudes da divisão do trabalho na manufatura, considerando o processo de subsunção formal à subsunção real do trabalho ao capital, ou seja, estudamos como ocorre a inserção da maquinaria no processo produtivo. Em seguida, analisamos o taylorismo e o fordismo - bem como o conceito de racionalização - como mecanismos de controle do trabalho operário. Por fim, investigamos a indústria de processo contínuo – ramo no qual se insere a indústria automática de vidro -, contrapondo-a com as características das indústrias tayloristas e fordistas / The organization of work in the auto glass industry is directly influenced by technology inserted in the production process. In this business, an integrated chain of automata performs the physical-chemical operations that embody the final product. Thus, the worker does not get directly involved in manufacturing and/or assembly, being only a supervisor of the process. This implies a number of important features to the auto glass industry: not only the work process itself is marked by such technological nuance but also - and along with that - the processes of management and organization of the company as a whole. In addressing the relationship between technology and production process, we must search capital / labor relation in its historical dynamic. Therefore, this study turns to a critical analysis, biased Marxist, of the main ways of management work that emerged throughout the historyof capitalism. First, we highlight the vicissitudes of division of labor in manufacturing, considering the process of formal subsumption to real subsumption of labor to capital, ie, we study how the inclusion of machinery occurs in the production process. We then analyze Taylorism and Fordism - as well as the concept of rationalization - as mechanisms of control of labor worker. Finally, we investigate the continuous process industry - in which sector the auto glass industry is inserted - contrasting it with the characteristics of Taylorist and Fordist industries

Este trabalho mostra uma aplicação de conceitos de produção enxuta em uma empresa de processo contínuo. Existe uma percepção por parte de algumas destas empresas de que, sendo de fluxo contínuo, elas se adequam mais aos princípios da produção em massa, não sendo portanto aplicáveis a elas os conceitos de produção enxuta. Também existe a crença, igualmente questionável, de que elas já são enxutas por natureza, devido ao elevado nível de automação com pouca manipulação e movimentações discretas. Este trabalho mostra que isso nem sempre é verdade e que uma empresa de processo contínuo pode se beneficiar consideravelmente da aplicação de conceitos de manufatura enxuta. É apresentada aqui uma revisão bibliográfica das principais ferramentas e conceitos de produção enxuta. Também é apresentado um caso já documentado na literatura técnica de aplicação destes conceitos em uma empresa química de processo contínuo. A seguir é mostrado o caso de aplicação de produção enxuta conduzida pelo autor em uma empresa de grande porte do setor termoplástico no estado de São Paulo, que tem características de processo contínuo. São também apresentados os resultados desta aplicação, evidenciando os ganhos obtidos como redução de 21% no indicador de refugo e 14% no tempo médio de set up, e algumas considerações sobre aplicação de produção enxuta em empresas desta natureza. / This paper shows a application of the concepts of lean production in a continuous process company. There is a misconception from some companies\' part that because they have continuous process, they fit more the mass production principles, therefore it is not valid to them the concept of lean production. There is also the belief, questionable as well, that they are naturally lean, due to the high level of automation with little handling and discret movements. This paper shows that this is not true and that continuous process company can benefit considerably from the application of the lean production concepts. It is presented here a bibliography review of the main tools and concepts of lean production. It is also presented a documented case of the application of these concepts in a chemical industry with continuous process. Next, the case of the application of lean production is showed, conducted by the author in a big company of termoplastic in the state of São Paulo that presents the characteristics of continuous process. The results of this application is presented, enfasizing the results obtained, it was obtained 21% of reduction in the screp indicator and 14% in the midium time of the set up and also some comments about the application of the lean production in these kinds of companies.

Apesar do crescimento nas exportações de açúcar, a conjuntura atual do setor sucroalcooleiro e a instabilidade do mercado externo têm feito com que as usinas busquem mais competitividade. A Tecnologia da Informação (TI) tem participação nesta busca, visto que, hoje, é impossível uma empresa apresentar um gerenciamento integrado eficaz sem a utilização de sistemas informatizados. Alguns desses sistemas, os ERP, têm se desenvolvido muito nos últimos anos, chegando, por exemplo, a ponto de possuírem módulos específicos para determinados tipos de empresas. Um dos desenvolvedores desses sistemas criou módulos específicos para o Planejamento e Controle da Produção (PCP) em indústrias de processo contínuo. Os conceitos envolvidos em tais módulos são apresentados nesta dissertação e comparados com os módulos tradicionais de Planejamento e Controle de Produção. Depois do embasamento conceitual, e da apresentação dos processos industriais de uma determinada usina de açúcar e álcool, é desenvolvida a configuração de tais módulo, para análise da compatibilidade desses ao processo produtivo da usina. / In spite of the growth in the sugar exports, the current situation of the sector responsible for the production of sugar and alcohol, as well as the instability of the external market, responsible for the fact that sugar and alcohol mills are looking for an increase competitiveness. The Information Technology (IT) has a great degree of participation in this search for competitiveness, because it is impossible for a company to introduce an effective integrated management network without the utilization of computerized systems. Some of these systems, called Enterprise Resources Planning, have developed remarkably in the last years, reaching, for instance, the point of having their own specific modules for certain industry types. One of the developers of these systems developed specific modules for the production planning and control in industries of continuous process. The concepts involved in such modules are introduced in this dissertation, and compared with the traditional modules of production planning and control. Basic concepts are introduced at first, then the industrial processes of a plant are explained, and the modeling of such company is presented for the analysis of the compatibility of the modules to the productive process of the plant.

Orientador: Pilar Rodriguez de Massaguer / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T11:41:03Z (GMT). No. of bitstreams: 1 Sanches_CristianaDePaulaPacheco_D.pdf: 39491118 bytes, checksum: 1b9b67b564e9684ca74114092ff37150 (MD5) Previous issue date: 2005 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Doutorado / Doutor em Ciência de Alimentos

Content: Leather goods are noble and sustainable but leather production may bear a potential for pollution. During leather manufacture high amounts of chromium shavings, wet by-products of the leather industry, are produced worldwide. Due to their chromium content they are disposed in landfill sites worldwide leading to long lasting environmental problems. They are stable towards temperatures of up to 110 °C and enzymatic degradation, preventing anaerobic digestion in a biogas plant. This stability is due to the three-dimensional native structure, typical for collagen, and additional chemical cross-links between the collagen fibers achieved by Cr3+ salts in the tanning step in tanneries. Therefore, hitherto chromium shavings are not utilized industrially to produce biogas. In order to ease enzymatic degradation, necessary to produce biogas, a previous denaturation of the native structure has to be carried out. Otherwise, the generation of biogas is hindered. In our projects, shavings were pre-treated thermally and mechanically by extrusion and hydrothermal methods. In previous works, we studied intensively the use of these shavings to produce biogas in batch scale and significant improvement was reached when using pre-treated shavings. In this work, a scale-up of the process was performed in a continuous reactor using pre-treated and untreated shavings to examine the feasibility of the considered method. Measuring different parameters along the anaerobic digestion, namely organic matter and volatile fatty acids content, it was possible to show that a higher loading rate can be used when feeding the reactor with pre-treated shavings instead of untreated shavings, which means a more economical process in an industrial scenario. Take-Away: The use of a pre-treatment improves the biogas production from chromium shavings