A indústria de papel e celulose passa por constantes desafios para solucionar problemas relacionados ao alto consumo de água industrial. Uma alternativa é utilizar ferramentas como a Integração de Processos, onde é possível aplicar técnicas gráficas como o \"Water Pinch\" ou técnicas com programação matemática para otimizar o circuito de água. Para contribuir com o setor, as técnicas foram aplicadas no presente trabalho utilizando-se dados reais coletados em uma unidade produtora de polpa termomecânica e papel imprensa. Com os dados, um caso base em um simulador foi desenvolvido para iniciar a análise por Integração de Processos. A análise é baseada no aproveitamento das correntes de águas residuais em outras etapas do processo sob restrições na concentração limite de contaminantes, especificamente finos e sólidos dissolvidos. Diferentemente dos trabalhos apresentados na literatura que alegam que a solução encontrada trata-se de valores otimizados, os resultados mostram que os valores encontrados através da programação matemática e do método Pinch são teoricamente corretos, porém, quando novamente simuladas sob estas novas condições obtidas por Integração de Processos, as condições operacionais da unidade industrial mostram-se inadequadas. As concentrações limites de contaminantes previamente estabelecidos pelas técnicas utilizadas são frequentemente ultrapassadas nos resultados de recálculo por simulação, e portanto, as soluções de Integração de Processos devem ser corrigidas antes de implantação. Por isso, os valores previstos, por exemplo, de redução de consumo de até 38% no projeto realístico atinge o valor de 23%, o que ainda é um bom resultado. O trabalho ainda mostra que a programação matemática é eficaz e rápida para encontrar soluções com múltiplos contaminantes, enquanto o método Pinch é mais voltado para casos com contaminante simples. / The Pulp and Paper industry has constantly struggled to solve problems related to high water consumption. One alternative is to use tools like Process Integration, where graphical methods and mathematical programming can be applied to optimize the water circuit. To contribute to the Pulp and Paper sector, the methods were applied in the present work using real process data that have been collected in an integrated thermomechanical and newsprint mill. With these data, a base case simulation was developed to initiate the analysis by Process Integration. The analysis is based on residual water reuse in other process stages under propriety constraints like contaminants concentration limits, specifically the dissolved solids and fine fibers. Differently from works presented in the references that claim that solutions found are optimized values, the results of this work show that values found by mathematical programming and pinch method are theoretically correct, however, the operational conditions of the mill become inadequate when simulated under new conditions achieved by Process Integration. The concentration limits of contaminants previously established for the methods have their values frequently exceed after recalculation by simulation, and thus, the solutions by Process Integration must be corrected before using them. So, if the predicted value for reduction of fresh water consumption is, for example, 38%, in the realistic project this value will reach only 23%, which is still a good result. The work also shows that mathematical programming is efficient to find solutions when there are multiple contaminants, while pinch method is more adequate for those cases with single contaminant.

With the growing interest in converting a wide variety of biomass-based feedstocks to biofuels, there is a need to develop effective procedures for the design and optimization of multi-feedstock biorefineries. The unifying goal of this work is the development of systematic methodologies and procedures for designing flexible multifeedstock biorefineries. This work addresses four problems that constitute building blocks towards achieving the unifying goal of the dissertation. The first problem addresses the design and techno-economic analysis of an integrated system for the production of biodiesel from algal oil. With the sequestration of carbon dioxide from power plant flue gases, algae growth and processing has the potential to reduce greenhouse gas emissions. Algae are a non-food oil feedstock source and various pathways and technologies for obtaining algal oil were investigated. Detailed economic and sensitivity analysis reveal specific scenarios that lead to profitability of algal oil as an alternative feedstock. In the second problem, a new safety metric is introduced and utilized in process design and selection. A case study was solved to assess the potential of producing biodiesel from sewage sludge. The entire process was evaluated based on multiple criteria including cost, technology and safety. The third problem is concerned with incorporating flexibility in the design phase of the development of multi-feedstock biofuel production processes. A mathematical formulation is developed for determining the optimal flexible design for a biorefinery that is to accommodate the use of multiple feedstocks. Various objective functions may be utilized for the flexible plant depending on the purpose of the flexibility analysis and a case study is presented to demonstrate one such objective function. Finally, the development of a systematic procedure for incorporating flexibility and heat integration in the design phase of a flexible feedstock production process is introduced for the fourth problem. A mathematical formulation is developed for use in determining the heat exchange network design. By incorporating the feedstock scenarios under investigation, a mixed integer linear program is generated and a flexible heat exchange network scheme can be developed. The solution provides for a network that can accommodate the heating and cooling demands of the various scenarios while meeting minimum utility targets.

Η εργασία αυτή παρουσιάζει την Βusiness-to-Βusiness πλευρά των αλυσίδων εφοδιασμού, εξετάζοντας τα χαρακτηριστικά των e-Επιχειρείν σχέσεων και της σημασίας τους για την εφαρμογή τεχνολογιών e-Επιχειρείν, εστιάζοντας όμως στο θέμα της ενοποίησης των e-Διεργασιών και των εμποδίων προς την κατεύθυνση αυτή. Συζητούνται επιλεκτικά μερικά από τα ευρέως υιοθετημένα πρότυπα, έτσι ώστε να γίνουν κατανοητοί οι τρόποι με τους οποίους οι μεγάλες βιομηχανικές πρωτοβουλίες προσπαθούν να αντιμετωπίσουν το γεγονός ότι το e-Επιχειρείν περιβάλλον αντανακλά τους ιδιοσυγκρασιακούς τρόπους με τους οποίους οι επιχειρηματικές διεργασίες λειτουργούν μέσα σε έναν οργανισμό και δημιουργούν ασυνέπειες στην διαλειτουργικότητά τους. Εξετάζεται το πρόβλημα της Ενοποίησης Επιχειρηματικών Διεργασιών και γίνεται εμφανές πως είναι πιθανώς αδύνατο αυτό να αντιμετωπιστεί στο σημείο αυτό στην πλήρη έκτασή του. Για τον σκοπό αυτό, οι τεχνικές και επιχειρηματικές πλευρές της ενοποίησης αποσυνδέονται και εξετάζονται ξεχωριστά, με έμφαση στην επιχειρηματική πλευρά, καθώς διαπιστώνεται έλλειψη λύσεων στον τομέα αυτό. Η μετακίνηση αυτή του βάρους προς την επιχειρηματική πλευρά του προβλήματος οδηγεί στο θέμα των σημασιολογικών ασυνεπειών κατά την ανταλλαγή πληροφορίας μεταξύ επιχειρηματικών διεργασιών, τόσο σε επίπεδο δεδομένων όσο και διεργασιών. Για το σκοπό αυτό, παρουσιάζεται ένα Μοντέλο Συνεργατικών Διεργασιών – Collaborative Process Model (CPM) που προσπαθεί να αντιμετωπίσει την έλλειψη ενός κοινού μοντέλου αναφοράς για ανόμοια μοντέλα διεργασιών, στοχεύοντας στο να επιτρέψει την ευθυγράμμιση ανόμοιων επιχειρηματικών μοντέλων. Τα λειτουργικά και εννοιολογικά χαρακτηριστικά του μοντέλου αυτού συζητούνται και στην συνέχεια διατυπώνονται και σε τυπική μορφή, επιδεικνύοντας τον τρόπο με τον οποίο μια πιο αφαιρετική προσέγγιση στην περιγραφή των διεργασιών μπορεί να χρησιμοποιηθεί για να τους επιτρέψει να συνεργαστούν στη δημιουργία μεγαλύτερων δομών όπως οι αλυσίδες διεργασιών. Στη συνέχεια παρουσιάζεται η εφαρμογή του CPM σε ένα επιχειρηματικό πεδίο ως μια μελέτη της εφαρμοσιμότητας και λειτουργικότητας του μοντέλου. / This work discusses the Business-to-Business aspect of supply chains, examining the characteristics of the e-Business relationships and their relevance for the application of e-Business technology, but focusing on the issue of the integration of e-Business Processes and the impediments in this effort. A selection of widely adopted business standards is being presented in order to get a glimpse of the ways that major industrial efforts are trying to deal with the fact that the e-Business environment reflects the idiosyncratic ways that the business processes work within an organization, and create inconsistencies in their interoperation. The problem of Business Process Integration is being discussed, and what becomes evident during that discussion is that the problem is probably impossible to handle at this point in its full extent. For this purpose, the technical- and business-related aspects of the integration are decoupled and examined in isolation, with the emphasis put on the business aspect, due to the lack of solutions for this part of the problem. Since the focus is moved towards the business level issues then this inadvertently leads to the problem of the semantic inconsistencies during the exchange of information between processes, both on data and process level. For this purpose, a Collaborative Process Model - CPM is presented that attempts to address the lack of a common reference model for the description of business information and business logic, aiming to enable the alignment of disparate process models. The functional and conceptual characteristics of the Model are being discussed and consequently formally defined, showing how a more abstract approach in the description of the processes can be utilized in order to allow them to cooperate in the creation of bigger structures like process chains. Following on, the application of CPM to a business domain is presented as a proof of concept of its applicability and functionality.

Requirements Engineering (RE) approaches are widely used in several domains such as telecommunications systems, information systems, and even regulatory compliance. However, they are rarely applied in healthcare beyond requirements elicitation. Healthcare is a multidisciplinary environment in which clinical processes are often performed across multiple units. Introducing a new Information Technology (IT) system or a new process in such an environment is a very challenging task, especially in the absence of recognized RE practices. Currently, many IT systems are not welcomed by caregivers and are considered to be failures because they change what caregivers are familiar with and bring new tasks that often consume additional time. This thesis introduces a new RE-based approach aiming to evaluate and estimate the potential impact of new system integrations on current practices, organizational goals,and user satisfaction using goal modelling and process modelling techniques. This approach is validated with two case studies conducted in real hospitals and a usability study involving healthcare practitioners. The contributions of the thesis are: • Major: a novel Activity-based Process Integration (AbPI) framework that enables the integration of a new process into existing practices incrementally, in a way that permits continuous analysis and evaluation. AbPI also provides several alternatives to a given integration to ensure effective flowing and minimal disturbance to current practices. AbPI has a Goal Integration Method to integrate new goals, an Integration Method to integrate new processes, and an Alternative Evaluation Method exploiting multi-criteria decision-making algorithms to select among strategies. The modelling concepts of AbPI are supported by a profile of the User Requirements Notation augmented with a new distance-based goal-oriented approach to alternative selection and a new data-quality-driven algorithm for the propagation of confidence levels in goal models. • Minor: a usability study of AbPI to investigate the usefulness of the framework in a healthcare context. This usability study is part of the validation and is also a minor contribution due to: 1) the lack of usability studies when proposing requirements engineering frameworks, and 2) an intent to discover the potential usefulness of the framework in a context where recognized RE practices are seldom used.

A água é uma matéria-prima estratégica na indústria química, petroquímica e de alimentos, sendo utilizada em diversas etapas dos processos. Devido à importância econômica e ao impacto ambiental resultante do consumo da água na indústria, o uso racional da água vem sendo amplamente enfatizado. Nas últimas décadas, diversas metodologias foram propostas para a minimização do consumo de água e emissão de efluentes líquidos na indústria, baseadas em conceitos de integração mássica como reuso, reciclo e regeneração das correntes que conectam os processos. As metodologias propostas na literatura para a integração mássica dividem-se em dois grandes grupos: o primeiro utiliza a abordagem termodinâmica-heurística-evolutiva, enquanto que o segundo faz uso da programação matemática e otimização. Ambas as metodologias apresentam dificuldades para tratar do caso de múltiplos poluentes, sendo que na primeira, é necessário uma série de aproximações para tratar deste tipo de problema e na segunda estão presentes limitações relativas aos métodos de otimização. Além disso, sistemas integrados massicamente podem apresentar dificuldades operacionais devido ao maior número de reciclos e reusos de correntes. O presente trabalho através do uso de ferramentas de programação matemática e, baseado no problema padrão de síntese de redes proposto por Fontana (2002), propõe métodos para a redução da complexidade do problema de síntese e obtenção de redes integradas massicamente, considerando aspectos econômicos e operacionais. Inicialmente foi proposta a eliminação de variáveis inteiras do problema de otimização, transformando o problema de programação nãolinear inteira-mista (MINLP) em um problema de programação não-linear (NLP). Em seguida, foi proposta uma metodologia para a redução da complexidade do problema baseada na utilização das restrições de igualdade, reduzindo o número de variáveis de decisão. As formulações propostas apresentaram bons resultados, diminuindo consideravelmente o tempo computacional em relação ao problema MINLP original. Baseada nas metodologias desenvolvidas para redução da complexidade do problema, foi implementado ainda um gerador de estimativas iniciais viáveis utilizando números aleatórios. Também foram propostas três implementações para a síntese de redes com considerações econômicas e operacionais, resolvendo o problema de otimização em dois níveis: um externo para avaliação de critérios econômicos e um interno de onde é obtido o índice operacional. Das três formulações com considerações operacionais propostas, duas apresentaram redes com melhor desempenho operacional quando comparadas com os problemas somente com considerações econômicas. Tais resultados foram avaliados através de simulações dinâmicas com modelos linearizados, sendo observado, nestas duas implementações, aumento da robustez do sistema (redução da ação de controle sobre as variáveis manipuladas) frente a distúrbios positivos nas cargas de poluentes e mudanças nos set-points das variáveis controladas. / Water is an important raw material in the chemical, petrochemical, and food industry, being used in several stages of a process. Based on the economic importance of the water and the environmental impact through its employment in the industry, its rational consume has been receiving special attention. In the past decades, several methodologies have been proposed for the minimization of industrial water consume and wastewater emissions based on concepts of mass integration such as reuse, recycle, and regeneration of process streams. The methodologies proposed in the literature for the mass integration can be classified in two main groups: the first uses the themodynamic-heuristic-evolutive approach while the second uses mathematical programming and optimization. Both methodologies show difficulties to deal with the case of multiple pollutants: on the first one it is necessary to make some assumptions to solve this problem while the second, limitations relative to optimization methods are present. Another problem is the operational limitations due to streams recycle and reuse, that integrated processes can present. The present study, through the use of mathematical programming tools, based on the synthesis problem proposed by Fontana (2002), proposes methods to reduce the problem complexity and also for the synthesis of mass integration networks regarding economical and operational aspects. Initially it was proposed the elimination of the integer variables from the optimization problem, changing the problem from mixed-integer nonlinear programming (MINLP) to nonlinear programming (NLP). In the following, a methodology for the reduction of the problems complexity, based on the equality constraints, was applied to reduce the number of decision variables. The proposed formulations showed good results, reducing the computational time comparing to the MINLP problem. Based on the proposed methodologies for the reduction of the problem complexity described above, it was implemented a feasible initial guess generator based on random numbers. It was also proposed three formulations for the network synthesis with economic and operational considerations, solving the synthesis problem in two levels: an external level for the evaluation of economical criteria and an internal level where the operational index is obtained. Two out of the three implementations presented networks with better operational results comparing with problems only with economical aspects. These results were evaluated by dynamic simulations with linearized models and it was observed an increase in the systems robustness (reduction of the control action over the manipulated variables) when the system was subjected to positive disturbances in the pollutants loads and set-points changes.

A água é uma matéria-prima estratégica na indústria química, petroquímica e de alimentos, sendo utilizada em diversas etapas dos processos. Devido à importância econômica e ao impacto ambiental resultante do consumo da água na indústria, o uso racional da água vem sendo amplamente enfatizado. Nas últimas décadas, diversas metodologias foram propostas para a minimização do consumo de água e emissão de efluentes líquidos na indústria, baseadas em conceitos de integração mássica como reuso, reciclo e regeneração das correntes que conectam os processos. As metodologias propostas na literatura para a integração mássica dividem-se em dois grandes grupos: o primeiro utiliza a abordagem termodinâmica-heurística-evolutiva, enquanto que o segundo faz uso da programação matemática e otimização. Ambas as metodologias apresentam dificuldades para tratar do caso de múltiplos poluentes, sendo que na primeira, é necessário uma série de aproximações para tratar deste tipo de problema e na segunda estão presentes limitações relativas aos métodos de otimização. Além disso, sistemas integrados massicamente podem apresentar dificuldades operacionais devido ao maior número de reciclos e reusos de correntes. O presente trabalho através do uso de ferramentas de programação matemática e, baseado no problema padrão de síntese de redes proposto por Fontana (2002), propõe métodos para a redução da complexidade do problema de síntese e obtenção de redes integradas massicamente, considerando aspectos econômicos e operacionais. Inicialmente foi proposta a eliminação de variáveis inteiras do problema de otimização, transformando o problema de programação nãolinear inteira-mista (MINLP) em um problema de programação não-linear (NLP). Em seguida, foi proposta uma metodologia para a redução da complexidade do problema baseada na utilização das restrições de igualdade, reduzindo o número de variáveis de decisão. As formulações propostas apresentaram bons resultados, diminuindo consideravelmente o tempo computacional em relação ao problema MINLP original. Baseada nas metodologias desenvolvidas para redução da complexidade do problema, foi implementado ainda um gerador de estimativas iniciais viáveis utilizando números aleatórios. Também foram propostas três implementações para a síntese de redes com considerações econômicas e operacionais, resolvendo o problema de otimização em dois níveis: um externo para avaliação de critérios econômicos e um interno de onde é obtido o índice operacional. Das três formulações com considerações operacionais propostas, duas apresentaram redes com melhor desempenho operacional quando comparadas com os problemas somente com considerações econômicas. Tais resultados foram avaliados através de simulações dinâmicas com modelos linearizados, sendo observado, nestas duas implementações, aumento da robustez do sistema (redução da ação de controle sobre as variáveis manipuladas) frente a distúrbios positivos nas cargas de poluentes e mudanças nos set-points das variáveis controladas. / Water is an important raw material in the chemical, petrochemical, and food industry, being used in several stages of a process. Based on the economic importance of the water and the environmental impact through its employment in the industry, its rational consume has been receiving special attention. In the past decades, several methodologies have been proposed for the minimization of industrial water consume and wastewater emissions based on concepts of mass integration such as reuse, recycle, and regeneration of process streams. The methodologies proposed in the literature for the mass integration can be classified in two main groups: the first uses the themodynamic-heuristic-evolutive approach while the second uses mathematical programming and optimization. Both methodologies show difficulties to deal with the case of multiple pollutants: on the first one it is necessary to make some assumptions to solve this problem while the second, limitations relative to optimization methods are present. Another problem is the operational limitations due to streams recycle and reuse, that integrated processes can present. The present study, through the use of mathematical programming tools, based on the synthesis problem proposed by Fontana (2002), proposes methods to reduce the problem complexity and also for the synthesis of mass integration networks regarding economical and operational aspects. Initially it was proposed the elimination of the integer variables from the optimization problem, changing the problem from mixed-integer nonlinear programming (MINLP) to nonlinear programming (NLP). In the following, a methodology for the reduction of the problems complexity, based on the equality constraints, was applied to reduce the number of decision variables. The proposed formulations showed good results, reducing the computational time comparing to the MINLP problem. Based on the proposed methodologies for the reduction of the problem complexity described above, it was implemented a feasible initial guess generator based on random numbers. It was also proposed three formulations for the network synthesis with economic and operational considerations, solving the synthesis problem in two levels: an external level for the evaluation of economical criteria and an internal level where the operational index is obtained. Two out of the three implementations presented networks with better operational results comparing with problems only with economical aspects. These results were evaluated by dynamic simulations with linearized models and it was observed an increase in the systems robustness (reduction of the control action over the manipulated variables) when the system was subjected to positive disturbances in the pollutants loads and set-points changes.

A indústria de papel e celulose passa por constantes desafios para solucionar problemas relacionados ao alto consumo de água industrial. Uma alternativa é utilizar ferramentas como a Integração de Processos, onde é possível aplicar técnicas gráficas como o \"Water Pinch\" ou técnicas com programação matemática para otimizar o circuito de água. Para contribuir com o setor, as técnicas foram aplicadas no presente trabalho utilizando-se dados reais coletados em uma unidade produtora de polpa termomecânica e papel imprensa. Com os dados, um caso base em um simulador foi desenvolvido para iniciar a análise por Integração de Processos. A análise é baseada no aproveitamento das correntes de águas residuais em outras etapas do processo sob restrições na concentração limite de contaminantes, especificamente finos e sólidos dissolvidos. Diferentemente dos trabalhos apresentados na literatura que alegam que a solução encontrada trata-se de valores otimizados, os resultados mostram que os valores encontrados através da programação matemática e do método Pinch são teoricamente corretos, porém, quando novamente simuladas sob estas novas condições obtidas por Integração de Processos, as condições operacionais da unidade industrial mostram-se inadequadas. As concentrações limites de contaminantes previamente estabelecidos pelas técnicas utilizadas são frequentemente ultrapassadas nos resultados de recálculo por simulação, e portanto, as soluções de Integração de Processos devem ser corrigidas antes de implantação. Por isso, os valores previstos, por exemplo, de redução de consumo de até 38% no projeto realístico atinge o valor de 23%, o que ainda é um bom resultado. O trabalho ainda mostra que a programação matemática é eficaz e rápida para encontrar soluções com múltiplos contaminantes, enquanto o método Pinch é mais voltado para casos com contaminante simples. / The Pulp and Paper industry has constantly struggled to solve problems related to high water consumption. One alternative is to use tools like Process Integration, where graphical methods and mathematical programming can be applied to optimize the water circuit. To contribute to the Pulp and Paper sector, the methods were applied in the present work using real process data that have been collected in an integrated thermomechanical and newsprint mill. With these data, a base case simulation was developed to initiate the analysis by Process Integration. The analysis is based on residual water reuse in other process stages under propriety constraints like contaminants concentration limits, specifically the dissolved solids and fine fibers. Differently from works presented in the references that claim that solutions found are optimized values, the results of this work show that values found by mathematical programming and pinch method are theoretically correct, however, the operational conditions of the mill become inadequate when simulated under new conditions achieved by Process Integration. The concentration limits of contaminants previously established for the methods have their values frequently exceed after recalculation by simulation, and thus, the solutions by Process Integration must be corrected before using them. So, if the predicted value for reduction of fresh water consumption is, for example, 38%, in the realistic project this value will reach only 23%, which is still a good result. The work also shows that mathematical programming is efficient to find solutions when there are multiple contaminants, while pinch method is more adequate for those cases with single contaminant.

A água é uma matéria-prima estratégica na indústria química, petroquímica e de alimentos, sendo utilizada em diversas etapas dos processos. Devido à importância econômica e ao impacto ambiental resultante do consumo da água na indústria, o uso racional da água vem sendo amplamente enfatizado. Nas últimas décadas, diversas metodologias foram propostas para a minimização do consumo de água e emissão de efluentes líquidos na indústria, baseadas em conceitos de integração mássica como reuso, reciclo e regeneração das correntes que conectam os processos. As metodologias propostas na literatura para a integração mássica dividem-se em dois grandes grupos: o primeiro utiliza a abordagem termodinâmica-heurística-evolutiva, enquanto que o segundo faz uso da programação matemática e otimização. Ambas as metodologias apresentam dificuldades para tratar do caso de múltiplos poluentes, sendo que na primeira, é necessário uma série de aproximações para tratar deste tipo de problema e na segunda estão presentes limitações relativas aos métodos de otimização. Além disso, sistemas integrados massicamente podem apresentar dificuldades operacionais devido ao maior número de reciclos e reusos de correntes. O presente trabalho através do uso de ferramentas de programação matemática e, baseado no problema padrão de síntese de redes proposto por Fontana (2002), propõe métodos para a redução da complexidade do problema de síntese e obtenção de redes integradas massicamente, considerando aspectos econômicos e operacionais. Inicialmente foi proposta a eliminação de variáveis inteiras do problema de otimização, transformando o problema de programação nãolinear inteira-mista (MINLP) em um problema de programação não-linear (NLP). Em seguida, foi proposta uma metodologia para a redução da complexidade do problema baseada na utilização das restrições de igualdade, reduzindo o número de variáveis de decisão. As formulações propostas apresentaram bons resultados, diminuindo consideravelmente o tempo computacional em relação ao problema MINLP original. Baseada nas metodologias desenvolvidas para redução da complexidade do problema, foi implementado ainda um gerador de estimativas iniciais viáveis utilizando números aleatórios. Também foram propostas três implementações para a síntese de redes com considerações econômicas e operacionais, resolvendo o problema de otimização em dois níveis: um externo para avaliação de critérios econômicos e um interno de onde é obtido o índice operacional. Das três formulações com considerações operacionais propostas, duas apresentaram redes com melhor desempenho operacional quando comparadas com os problemas somente com considerações econômicas. Tais resultados foram avaliados através de simulações dinâmicas com modelos linearizados, sendo observado, nestas duas implementações, aumento da robustez do sistema (redução da ação de controle sobre as variáveis manipuladas) frente a distúrbios positivos nas cargas de poluentes e mudanças nos set-points das variáveis controladas. / Water is an important raw material in the chemical, petrochemical, and food industry, being used in several stages of a process. Based on the economic importance of the water and the environmental impact through its employment in the industry, its rational consume has been receiving special attention. In the past decades, several methodologies have been proposed for the minimization of industrial water consume and wastewater emissions based on concepts of mass integration such as reuse, recycle, and regeneration of process streams. The methodologies proposed in the literature for the mass integration can be classified in two main groups: the first uses the themodynamic-heuristic-evolutive approach while the second uses mathematical programming and optimization. Both methodologies show difficulties to deal with the case of multiple pollutants: on the first one it is necessary to make some assumptions to solve this problem while the second, limitations relative to optimization methods are present. Another problem is the operational limitations due to streams recycle and reuse, that integrated processes can present. The present study, through the use of mathematical programming tools, based on the synthesis problem proposed by Fontana (2002), proposes methods to reduce the problem complexity and also for the synthesis of mass integration networks regarding economical and operational aspects. Initially it was proposed the elimination of the integer variables from the optimization problem, changing the problem from mixed-integer nonlinear programming (MINLP) to nonlinear programming (NLP). In the following, a methodology for the reduction of the problems complexity, based on the equality constraints, was applied to reduce the number of decision variables. The proposed formulations showed good results, reducing the computational time comparing to the MINLP problem. Based on the proposed methodologies for the reduction of the problem complexity described above, it was implemented a feasible initial guess generator based on random numbers. It was also proposed three formulations for the network synthesis with economic and operational considerations, solving the synthesis problem in two levels: an external level for the evaluation of economical criteria and an internal level where the operational index is obtained. Two out of the three implementations presented networks with better operational results comparing with problems only with economical aspects. These results were evaluated by dynamic simulations with linearized models and it was observed an increase in the systems robustness (reduction of the control action over the manipulated variables) when the system was subjected to positive disturbances in the pollutants loads and set-points changes.

[pt] A globalização da competição tem forçado as organizações a buscar e implementar novas vertentes geradoras de vantagens competitivas. Como na atualidade a competição ocorre freqüentemente entre cadeias de suprimentos e não entre empresas isoladas, a Gestão da Cadeia de Suprimentos (Supply Chain Management - SCM) aparece como uma nova fronteira a ser explorada. Em função dessas considerações, esta dissertação tem por objetivo de aplicar o Modelo para SCM de Aragão et al. (2004) para analisar cadeias de suprimentos baseadas em dimensões-chave necessárias para uma bem sucedida SCM. As dimensões-chave consideradas neste modelo são: integração de processos de negócios, identificação dos membros-chave da cadeia, compartilhamento de informação e medidas de desempenho relacionadas à cadeia de suprimento de uma empresa fabricante de gases industriais no mercado Brasileiro. Este fabricante é considerado nesta dissertação como a empresa focal da cadeia de suprimentos. Cinco membros-chave desta cadeia são também incorporados na análise. Conclui-se que a empresa focal possui diferentes formas de gerir a sua cadeia em função de cada membro chave. / [en] The globalization of competition has forced the organizations to seek and to implement new forms to create competitive advantages. Nowadays, as competition occurs effectively between supply chains and not between isolated companies, SCM (Supply Chain Management) appears as a new frontier to be explored. Within this context, this dissertation has the objective to apply the model for SCM proposed in Aragão et al. (2004) to analyze the supply chains based on key-dimensions for a successful SCM. The key- dimensions considered in this model are: business process integrations, identification of the supply chain key-member, sharing of information and measures of performance related to the supply chain of an industrial gas manufacturer in the Brazilian market. This manufacturer is considered in this dissertation as the focal company of the supply chain. Five key-members of this chain are also included in the analysis. As a result the analyses, it is possible to conclude that the focal company develops different ways to manage its chain depending on each of its key members.

Renewability and the carbonaceous basis of biomass provide potential for both energy and chemical production in biorefineries in a fashion similar to crude oil refineries. Biorefineries are envisaged as having a key role in the transition to a more sustainable industry, especially as a means to mitigate greenhouse gas (GHG) emissions. A biorefinery is a concept for the flexible, efficient, cost-effective and sustainable conversion of biomass through a combination of process technologies into multiple products. This implies that biorefineries must be integrated through designs that exploit the interactions between material and energy streams. The wide range of possibilities for biomass feedstock, processes and products poses a challenge to biorefinery design. Integrating biorefineries within evolving economic and environmental policy contexts requires careful analysis of the configurations to be deployed from early in the design stage. This research therefore focuses on the application and development of methodologies for biorefinery design encompassing process integration tools, economic and environmental sustainability analyses together. The research is presented in the form of papers published or submitted to relevant peer-reviewed journals, with a preamble for each paper and a final synthesis of the work as a whole. In a first stage, mass pinch analysis was adapted into a method for integration ofbiorefineries producing bioethanol as a final product and also utilising bioethanol asa working fluid within the biorefinery. The tool allows targeting minimum bioethanol utilisation and assessing network modifications to diminish revenue losses. This new application could stimulate the emergence of similar approaches for the design of integrated biorefineries. The thesis then moves to combine feedstock production models, process simulations in Aspen Plus® and process integration with LCA, to improve energy efficiency and reduce GHG emissions of biorefineries. This work, presented via two publications covering wheat to bioethanol and Jatropha to biodiesel or green diesel, provided evidence of the benefits of biorefinery integrationfor energy saving and climate change adaptation. The multilevel modelling approach is then further integrated into a methodologydeveloped for the combined evaluation of the economic potential and GHG emissions saving of a biorefinery from the marginal performances of biorefineryproducts. The tool allows assessing process integration pathways and targeting forpolicy compliance. The tool is presented via two further publications, the first drawing analogies between value analysis and environmental impact analysis inorder to create the combined Economic Value and Environmental Impact (EVEI)analysis methodology, the second extending this to demonstrate how the tool canguide judicious movement of environmental burdens to meet policy targets. The research embodied in this thesis forms a systematic basis for the analysis andgeneration of biorefinery process designs for enhanced sustainability. The toolspresented will facilitate both the implementation of integrated biorefinery designsand the cultivation of a community of biorefinery engineers for whom suchintegrated thinking is their distinctive and defining attribute.