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- Sustainable product design education: engineering students’ perceptions and attitudesPublication . João, Isabel; Silva, JoãoMoving towards sustainable development is a global challenge requiring efforts from all the society, but governments and other stakeholders as well as researchers and academics have a central role to aid put in practice the knowledge and tools to enforce the vital changes. This work was developed to better understand the topic of sustainable product design among engineering students given the deficit of such kind of studies in the master courses of our engineering department. Survey data were collected from engineering students enrolled in master courses that have in its syllabus the product design curricular unit. The main objective of the work was to understand the students’ perceptions and attitudes in relation to sustainable product design to envisage actions to continually improve the course with the goal of developing students’ further knowledge and competencies with the focus on cradle to cradle design strategies.
- Use of excess heat from ethylene recycling in a low-density polyethylene production plantPublication . Matos, Rodolfo D. C.; João, Isabel; Silva, JoãoThe recovery of the wasted heat is an effective way of improving the energy efficiency of industry sites and can contribute to the reduction of the operating costs and the CO2 emissions. In the production of low density polyethylene, the polymerisation reaction is carried out with a large excess of ethylene at very high pressure. The excess ethylene is separated at an intermediate pressure (around 280 bar and 310 °C) and then it is recycled. In this recycle, the stream is cooled in several steps to temperatures close to 35 °C before being recompressed. In some units, the first cooling is carried out with air coolers up to temperatures around 130 °C. In a unit with a recycle of 33 t/h, this cooling corresponds to releasing to the atmosphere about 4.6 MW of thermal power. We present a study of different alternatives for the use of this excess heat. We studied the implementation of a refrigeration cycle by absorption with LiBr/H2O, the production of steam and the electricity generation by Rankine and Kalina cycles. The Aspen HYSYS process simulator was used to study the different alternatives. The capital cost was estimated for each of the evaluated options as well as the benefits expected to be obtained. In the study conditions, the absorption refrigeration cycle is the best solution presenting a return period of 3 years.
- Evaluating the degree of gelation of PVC-U pipes. Comparison of currently available methodsPublication . Real, L. E. Pimentel; João, Isabel; Pimenta, S. I.; Diogo, HerminioHealth and Safety policies have led to the recommendation of alternative tests to evaluate the resistance to dichloromethane to estimate the degree of gelation of rigid PVC pipes (PVC-U). In this work, we confirm that DSC is the best alternative method for evaluating the degree of gelation of rigid PVC pipes, using the relation between the enthalpy of fusion of primary and secondary crystallites, which were measured from respective endotherms. The suitability of this method is established by comparison with experimental results obtained with the test for determining the resistance to dichloromethane. Indeed, this method has proven to be fairly reliable and is the only one that allows the quantification of the degree of gelation.
- Exploring students entrepreneurial mindset. Insights to foster entrepreneurship in engineering educationPublication . João, Isabel; Silva, JoãoHigher education graduates have a huge potential forinnovative processes and sustainable economic development. The higher education institutions must play an important role in engaging students for entrepreneurial careers, enhancing their skills in entrepreneurship. Students capable of identifying opportunities and turning ideas into business, who have good communication and leadership skills as well as strong technical competencies are likely to be highly valued in the marketplace. This paper presents the results of a survey to investigate students’ entrepreneurial mindset. The main concern is to understand the interest of the students in entrepreneurship and reasons to start or not start a business, the engineering students’ perceptions of their entrepreneurial related abilities, as well as their perception about the extent by which entrepreneurship is addressed in their engineering programs. The students were selected among two engineering master courses in a Portuguese Engineering School of a Polytechnic Institute. The curricular unit of entrepreneurship is part of the curriculum in one of the master course, while in the other course the students do not have such subject in their study program. The data were collected to investigate differences within and across engineering students who are and who are not participating in entrepreneurship courses as well as diferences concerning some demographic characteristics.
- Excess‐heat recovery and promotion through organic chemical heat pumpsPublication . Silva, Luís António Pinela da; João, Isabel; Silva, JoãoHeat recovery and promotion is essential to decarbonization, and chemical heat pumps based on reversible organic reactions can aid to fulfil this. This paper stud ied the isopropanol/acetone/hydrogen (IAH) and the tert-butanol/isobutene/water (tB/iB) systems regarding their performance and economic competitiveness through simulation and found that the IAH presents satisfactory performance and has the potential to be a very promising solution in increasing the overall energy efficiency while also preventing the emission of massive amounts of CO2 and other greenhouse gases released during energy production and transforma tion. This system presents enough arguments to become a very successful solution if proper politico-economic support and incentives are established and put into practice.
- The role of higher education towards sustainable consumption behavioural change: topics discussed in sustainable consumption educationPublication . João, Isabel; Silva, JoãoMany factors have contributed to the urgency of adopting sustainable consumption patterns. The main challenges related to sustainable consumption include respecting our planet in all its complexity and diversity, taking care of communities and life and, to this end, adopting consumption and production patterns that protect human rights and the well-being of communities. The theme of education for sustainable consumption is multidisciplinary with elements from different curriculum topics and addresses all aspects of everyday life. Establishing a common understanding of sustainable consumption education will create a shared understanding of the topic and improve the necessary cooperation between educators and students, making sustainable consumption education an established and more understandable topic. The objective of this study is to identify the main topics within sustainable consumption education teaching and learning, the main barriers and propose some actions that contribute to a sustainable behavioural change in higher education. A literature review was carried out to categorize the main topics related to teaching and learning processes in higher education environments to fill the gap in this underrepresented research topic of education for sustainable consumption. The review allowed the collection of information reported in this new millennium and the identification, selection and critical evaluation of research related to education for sustainable consumption.
- Designing and teaching a curricular unit to accomplish the outcomes related learning objectivesPublication . João, Isabel; Silva, JoãoThis paper describes how a curricular unit of Advanced Techniques for Quality was designed in the Quality and Environmental Engineering Master Course to satisfy the outcomes defined in the unit. This paper seeks to (1) explain the steps to take into consideration in the design of a curricular unit, (2) explain the outcomes related learning objectives of the specified curricular unit, (3) identify the instructional techniques that are used in the unit to prepare students to achieve those curricular unit outcomes, as well as the selected assessment methods and (4) describe how an active learning project is used as a teaching learning methodology to help the students to attain the learning outcomes defined in the unit.
- TRIZ and MACBETH in Chemical Process EngineeringPublication . João, Isabel; Silva, JoãoThe Chemical Process Industry (CPI) is facing an increasing pressure to develop new or improved chemical processes. The major challenges experienced by CPI is related with sustainability namely economic, social, and environmental issues, is the reason why innovation in chemical process design is becoming more challenging. However innovative chemical process design needs the support of a systematic innovation approach to guide engineers in the creation of new or improved chemical processes. The objective of this work is to present an approach that integrates the theory of inventive problem solving (TRIZ) and a multicriteria decision analysis method MACBETH for the selection of an improved chemical design among different options. The objective is to establish a systematic innovation approach to assist engineers or decision makers through the idea generation with TRIZ theory, and use MACBETH to perform the selection of the best-generated concept. The use of a combined approach in chemical process improvement may increase the efficiency of concept selection avoiding time waste. An illustration is presented in order to show the simplicity and applicability of the approach.
- Designing experiments with Aspen HYSYS simulation to improve distillation systems: Insights from a chemical engineering coursePublication . João, Isabel; Silva, JoãoDesigning experiments by simulation with process simulators, e.g. Aspen HYSYS, can be very effective in the optimization of several chemical engineering systems. It is important to enhance students' skills highlighting the value of applying problem specific knowledge, simulation tools and sound statistical techniques. This paper addresses the use of Aspen HYSYS by Portuguese chemical engineering master students to model distillation systems together with statistical experimental design techniques in order to optimize the systems. The paper presents a procedure followed in two projects beginning with the selection of two case studies from the literature, which the goal is to further improve with the help of design of experiments. The paper presents the work developed by the students in order to model steady-state and dynamic processes and optimize the distillation systems emphasizing the benefits of the simulation tools and statistical techniques in helping the students learn how to learn. Students strengthened their domain specific knowledge and became motivated to rethink and improve chemical processes in their future chemical engineering profession. The main results and conclusions provide a strong incentive from the teachers' perspective to a wider use of this kind of procedure by chemical engineering master students.
- Designing Solutions by a Student Centred Approach: Integration of Chemical Process Simulation with Statistical Tools to Improve Distillation SystemsPublication . João, Isabel; Silva, JoãoProjects thematically focused on simulation and statistical techniques for designing and optimizing chemical processes can be helpful in chemical engineering education in order to meet the needs of engineers. We argue for the relevance of the projects to improve a student centred approach and boost higher order thinking skills. This paper addresses the use of Aspen HYSYS by Portuguese chemical engineering master students to model distillation systems together with statistical experimental design techniques in order to optimize the systems highlighting the value of applying problem specific knowledge, simulation tools and sound statistical techniques. The paper summarizes the work developed by the students in order to model steady-state processes, dynamic processes and optimize the distillation systems emphasizing the benefits of the simulation tools and statistical techniques in helping the students learn how to learn. Students strengthened their domain specific knowledge and became motivated to rethink and improve chemical processes in their future chemical engineering profession. We discuss the main advantages of the methodology from the students’ and teachers perspective.