Percorrer por autor "Brito, Paulo"
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- 14th International Chemical and Biological Engineering Conference (CHEMPOR-2023): Book of AbstractsPublication . Queiroz, Ana; Peres, António M.; Ribeiro, António E.; Barreiro, Filomena; Ferreira, Olga; Brito, Paulo; Pinho, SimãoWelcome to the 14th edition of the International Chemical and Biological Engineering Conference (ChemPor-2023) held at Bragança Polytechnic University (Instituto Politécnico de Bragança, IPB), Portugal, from 12 to 15 of September, 2023. This triennial conference, organized by a Portuguese Higher Education Institution and the Portuguese Engineers Association (Ordem dos Engenheiros), gathers experts from the chemical and biological engineering areas and related subjects to exchange knowledge and technological experiences within the academic, industrial, scientific, and technological communities. ChemPor-2023 addresses these research fields in different topics, from green chemistry to engineering education, always envisaging a sustainable development. The etymology of the word “conference”, from the Medieval Latin, means literally “bring together”. This 14th edition comes with a two-year delay following the global sanitary crisis since only a full inperson meeting could fulfill this purpose. ChemPor-2023 encompasses a gathering in a vivid, enlightening, and convivial way, and this hiatus did not limit this spirit or its objectives. The conference aims to celebrate creativity, diversity, and friendship among participants, promoting ideas exchange and fruitful interactions. We have circa 300 delegates from 4 continents, and your active participation is highly acknowledged. The general relevance of ChemPor-2023 is addressed in a variety of settings, including biorefinery, biotechnology, energy and environment, innovative materials, creation and design of novel reaction and separation processes, always foreseeing industrial applications for a sustainable shaping of the future. This edition includes an opening lecture by Jorge Calado in the immense but much less explored area of ArtScience, and an Honor Session dedicated to Alírio Rodrigues for his academic and scientific contributions, particularly regarding IPB. Besides, the conference includes 11 invited lectures from internationally recognized scientists and experts from the industry, 107 oral presentations distributed in 27 sessions, and 135 posters in two dedicated sessions. A session exclusively dedicated to companies and another for Ph.D. studies in industrial environments are to be highlighted. The “Professor Almiro e Castro” award, established in 2014 by PARALAB – Equipamentos Industrial and Laboratory SA, to recognize the scientific merit of a Portuguese professor or researcher in the last three years in the fields of Chemical and Biological Engineering, and related areas, will be announced at the closing of the conference. In that ceremony, the two best posters and the best oral communication awards by young scientists will also be granted. We want to reinforce our deepest appreciation to all the participants, but also to the members of the Honor, Scientific, and Local Organizing Committees for their invaluable contribution to the conference and acknowledge the institutional support of Instituto Politécnico de Bragança, Ordem dos Engenheiros, Centro de Investigação de Montanha, Sociedade Portuguesa de Química, and Câmara Municipal de Bragança. Expressing enormous gratitude is mandatory to all our Sponsors and associated scientific journals and publishers. Nothing could have been possible without all of you! Finally, our best wishes for success for the next ChemPor organization.
- 1D and 2D modeling and simulation of radial combustion propagation on Fe 2O 3/Al thermite systemsPublication . Brito, Paulo; Durães, Luísa; Portugal, AntónioIn previous works, a one-dimensional model was built to simulate the nonsteady radial combustion propagation on thin disk-shaped samples of Fe2O3/aluminum thermite mixtures and was successfully tested. Now, the purpose is to extend the referred model to the more sensible two-dimensional features of the samples, maintaining the main characteristics of the previous model: zero-order kinetics, conductive/radiative heat transfer, assumption of phase transitions, temperature and composition dependency for all system properties during propagation. Therefore, an adaptive numerical algorithm that conjugates a method of lines (MOL) strategy based on finite differences space discretizations, with a collocation scheme based on increasing level dyadic grids is applied for the solution of the problem. The particular integration method proves to cope satisfactorily with the steep traveling thermal wave in 1D and 2D spatial domains, either for trivial uniform mixing conditions, as in complex examples developed to feature more sophisticated circumstances, such as nonhomogeneous reactant mixing, which realistically replicate the observed experimental conditions.
- Acidic waste cooking oil valorization by biodiesel synthesis catalyzed by hydrogen sulfate 1-butyl-3-methylimidazoliumPublication . Baú, Ana; Lenzi, Giane G.; Ribeiro, António E.; Queiroz, Ana; Brito, PauloBiodiesel is a fuel that shows growing demand as a promising alternative to petroleum-derived fuels. It is produced by esterification or transesterification reactions from renewable raw materials such as animal fats and vegetable oils , where the presence of catalysts is used for an effective conversion. The basic catalysts are very sensitive to the presence of water and FFAs, promoting saponification reactions. On the other hand, the use of acid catalysts means reaction times up to 4000 times higher, higher alcohol/oil molar ratios and higher reaction temperatures. In this context, Ionic Liquids (ILs) used as catalysts, come as a viable alternative to overcome these problems in biodiesel production processes. Imidazolium-based ILs, have been extensively studied, mainly due to their specific characteristics such as, low pressure and ability for self-organization in different states. Hydrogen sulfate 1-butyl-3-methylimidazolium [BMIM]HSO4 has been showing promising results in this type of applications. Therefore, the objective of this work is to study the application of the [BMIM]HSO4 IL in the catalysis of esterification/transesterification reactions of triglycerides mixtures with high free fatty acid contents coming from waste cooking oils samples, with further characterization of the quality of the biodiesel produced. The present work includes also the assessment of the catalyst potential for recovery and recycling.
- Acidic waste cooking oil valorization by biodiesel synthesis catalyzed by hydrogen sulfate 1-butyl-3-methylimidazoliumPublication . Baú, Ana; Lenzi, Giane G.; Ribeiro, António E.; Queiroz, Ana; Brito, PauloBiodiesel is a fuel that shows growing demand as a promising alternative to petroleum-derived fuels. It is produced by esterification or transesterification reactions from renewable raw materials such as animal fats and vegetable oils , where the presence of catalysts is used for an effective conversion. The basic catalysts are very sensitive to the presence of water and FFAs, promoting saponification reactions. On the other hand, the use of acid catalysts means reaction times up to 4000 times higher, higher alcohol/oil molar ratios and higher reaction temperatures. In this context, Ionic Liquids (ILs) used as catalysts, come as a viable alternative to overcome these problems in biodiesel production processes. Imidazolium-based ILs, have been extensively studied, mainly due to their specific characteristics such as, low pressure and ability for self-organization in different states.
- Adaptive collocation methods for the numerical solution of differential modelsPublication . Brito, Paulo; Portugal, AntónioA PDE integration algorithm that associates a Method of Lines (MOL) strategy based on finite differences or high resolution space discretizations, with a collocation strategy based on increasing level one or two-dimensional dyadic grids is presented. It reveals potential either as a grid generation procedure for predefined steep localised functions, and as an integration scheme for moving steep gradient PDE problems, namely 1D and 2D Burgers equations. Therefore, it copes satisfactorily with an example characterized by a steep 2D travelling wave and an example characterised by a forming steep travelling shock, which confirms its flexibility in dealing with diverse types of problems, with reasonable demands of computational effort.
- Adaptive collocation methods for the numerical solution of differential modelsPublication . Brito, Paulo; Portugal, AntónioA PDE integration algorithm that associates a Method of Lines (MOL) strategy based on finite differences or high resolution space discretizations, with a collocation strategy based on increasing level one or two-dimensional dyadic grids is presented. It reveals potential either as a grid generation procedure for predefined steep localised functions, and as an integration scheme for moving steep gradient PDE problems, namely 1D and 2D Burgers equations. Therefore, it copes satisfactorily with an example characterized by a steep 2D travelling wave and an example characterised by a forming steep travelling shock, which confirms its flexibility in dealing with diverse types of problems, with reasonable demands of computational effort.
- Adaptive collocation methods for the solution of partial differential equationsPublication . Brito, Paulo; Portugal, AntónioAn integration algorithm that conjugates a Method of Lines (MOL) strategy based on finite differences space discretizations, with a collocation strategy based on increasing level dyadic grids is presented. It reveals potential either as a grid generation procedure and a Partial Differential Equation(PDE) integration scheme. It copes satisfactorily with a example characterized by a steep travelling wave and a example that presented a forming steep shock, which demonstrates its versatility in dealing with different types of steep moving front problems, exhibiting features like advection-diffusion, widely common in the standard Chemical Processes simulation models.
- Analysis of the feasibility of the use as fertilizers, of leachates from a mechanical biological treatment plant for municipal solid wastePublication . Cardoso, Jonathan; Rodrigues, Bárbara; Gomes, Helder; Brito, PauloThe main environmental issue associated with the compost production is the production of a liquid leachate. However, compost leachate may also be considered as a source of nutrients and used as fertilizer. Chemical properties were determined for a raw leachate from a mechanical biological treatment plant for municipal solid waste, to check if it meets the adequate requirements for using as commercial fertilizer according to the proposal of regulation of the European Parliament of 2016, for fertilizers. This study intends to access if the leachate can be used as potential source for fertilizers. It qualitatively meets the requirements established for the composition of commercial fertilizers and the production cost of leachate as raw material is low. Preliminary results showed low concentrations of heavy metals and suitable amounts of nutrients after the concentration of the leachate by simple batch distillation.
- Analysis of the feasibility of the use as fertilizers, of leachates from a mechanical biological treatment plant for municipal solid wastePublication . Cardoso, Jonathan; Rodrigues, Bárbara; Gomes, Helder; Brito, PauloThe main environmental issue associated with the compost production is the production of a liquid leachate. Therewith, compost leachate may also be considered as a source of nutrients and used as fertilizer. The main pollution issue associated with this compost treatment is the production of a liquid leachate that is characterized by high organic load. Although municipal waste compost leachate is one of the problems of compost production, it may be considered as a source of nutrients. Compost leachate from municipal wastes contains carbon, nitrogen, phosphorus, potassium and trace elements that can be used as nutrients by plants. The advantages of the use of organic wastes such as compost leachate as fertilizers are evident. Their use would reduce the consumption of commercial fertilizers which need in their production high cost and energy. Leachate is a waste product, which means that no direct production costs are associated. The use of leachate in agriculture also means that the costs at waste treatment plants can be reduced, since processes for nitrogen and phosphorus removal would not be necessary. In that point of view, this work aims to determine the chemical properties for a raw leachate from a mechanical biological treatment plant for municipal solid waste, to check if it meets the adequate requirements for using as commercial fertilizer according to the proposal of regulation of the European Parliament of 2016, for fertilizers. This study intends to assess if the leachate can be used as potential source for fertilizers. It qualitatively meets the requirements established for the composition of commercial fertilizers and the production cost of leachate as raw material is low. Preliminary results showed low concentrations of heavy metals and suitable amounts of nutrients after the concentration of the leachate by simple batch distillation.
- Aplicação de métodos adaptativos para a simulação de processos de combustãoPublication . Brito, Paulo; Durães, Luísa; Campos, José; Portugal, AntónioMuitos dos modelos que envolvem combustão, nomeadamente da reacção da termite Fe2O3/Al, inserem-se numa classe de problemas cuja solução consiste na propagação de frentes abruptas de reacção exotérmica com dinâmica altamente não linear. Por outro lado, verifica-se a ocorrência de problemas de instabilidade (pulsação da frente, formação de modos de propagação rotacionais, etc), quando o valor de alguns parâmetros ultrapassa valores críticos. Dadas as condições extremas a que ocorrem as referidas reacções e à grande incerteza associada à estimativa de parâmetros importantes, esta classe de modelos constitui-se como um caso de estudo interessante para o teste de uma grande variedade de métodos numéricos adaptativos de integração (para geometrias uni- e multidimensionais). Deste modo, no presente trabalho aplica-se um método de adaptação de malha para a resolução de um modelo unidimensional que descreve o processo de combustão do sistema Fe2O3/Al. Conclui-se que o termo reactivo não se revela suficiente para auto-sustentar a propagação da frente, verificando-se um fenómeno de abrandamento e aceleração sucessivos, determinado pela competição entre as influências da condução de calor induzida pela condição fronteira e do calor libertado pela reacção. Conclui-se também ser necessária a análise mais aprofundada dos parâmetros e considerações do modelo e dos parâmetros numéricos, para uma descrição física mais consentânea com as características destes fenómenos. Pretende-se ainda futuramente estender o presente estudo a modelos de geometria radial bidimensionais, utilizando o método descrito e outros mais complexos – adaptação dinâmica e wavelets.