Constructivist-based experiential learning: A case study of student-centered and design-centric unit operation distillation laboratory

This paper presents the rationale for incorporating engineering design into project-based laboratory learning. To ensure an effective and efficient pedagogy for the new laboratory format, we placed the emphasis of the pedagogical framework on constructivist learning for deep laboratory learning, and integrated experiential learning cycle with cyclic engineering design to formulate a sequential instruction and formative assessment methodology. The implementation of the pedagogy was exemplified using a case study of a concrete distillation design consisting of conceptualizing the design, reasoning the adequacy and experiment-based validation of the design correlations, and verifying the final design as per experimental observations. The impact of the novel lab format on student learning experience was surveyed and compared to that of a traditional laboratory. The survey results revealed that the project-based laboratory with design resulted in an improved learning experience in addressing high-level learning outcomes and engineering skills. Evidence of the survey also suggested that the sequential instruction and formative assessment methodology was effective with every stage of the experiential learning and formative assessment essential for the successful and efficient implementation of the project-based laboratory learning.     

Making programme learning outcomes explicit for students of process and chemical engineering

There is a global shift in education from solely content-driven teaching to teaching that takes learning outcomes into account. This movement underpins much of the educational reform in the area of engineering education. Programme learning outcomes for degrees in engineering education are more commonplace as more and more professional accrediting bodies require fulfillment or compliance with prescribed learning outcomes. However, the students may not be presented with these learning outcomes as they are often “hidden” in documentation submitted by institutions for accreditation purposes and hence may not be divulged to students. Undergraduate students (2006–2008) taking the BE degree programme in Process & Chemical Engineering at UCC were first surveyed to assess their level of knowledge of the learning outcomes concept and of the degree programme learning outcomes. The contents of two documents used in applications for accreditation by professional accreditation bodies as well as professional Institution guidelines were reviewed to formulate the degree programme learning outcomes which were presented to the students. These students were then surveyed after the presentation. The results of the questionnaire completed by students demonstrated a major improvement in their knowledge of both the concept of learning outcomes and also of the degree programme learning outcomes. It also showed that the students found the session to be of overall beneficial value.     

Incorporating environmental impacts and regulations in a holistic supply chains modeling: An LCA approach

Corporate approaches to improve environmental performance cannot be undertaken in isolation, so a concerted effort along the supply chain (SC) entities is needed which poses another important challenge to managers. This work addresses the optimization of SC planning and design considering economical and environmental issues. The strategic decisions considered in the model are facility location, processing technology selection and production–distribution planning. A life cycle assessment (LCA) approach is envisaged to incorporate the environmental aspects of the model. IMPACT 2002+ methodology is selected to perform the impact assessment within the SC thus providing a feasible implementation of a combined midpoint–endpoint evaluation. The proposed approach reduces the value-subjectivity inherent to the assignment of weights in the calculation of an overall environmental impact by considering endpoint damage categories as objective function. Additionally, the model performs an impact mapping along the comprising SC nodes and activities. Such mapping allows to focus financial efforts to reduce environmental burdens to the most promising subjects. Furthermore, consideration of CO₂ trading scheme and temporal distribution of environmental interventions are also included with the intention of providing a tool that may be utilized to evaluate current regulatory policies or pursue more effective ones. The mathematical formulation of this problem becomes a multi-objective MILP (moMILP). Criteria selected for the objective function are damage categories impacts, overall impact factor and net present value (NPV). Main advantages of this model are highlighted through a realistic case study of maleic anhydride SC production and distribution network.     

A life cycle assessment of advanced biofuel production from a hectare of corn

Conventional agricultural life cycle assessments (LCAs) measure greenhouse gas (GHG) emissions for biofuel pathways as the amount of carbon dioxide equivalent emitted per unit of energy provided by the pathway (i.e. gCO₂e/MJ). This measure of GHG emissions, as computed by the Environmental Protection Agency (EPA) is then used to determine the extent to which the corresponding biofuel pathway complies with the GHG emission standards set forth by the Energy Independence and Security Act (EISA) of 2007. Under current legislation, ethanol produced from corn grain is prohibited from qualifying as an advanced biofuel, even if it were to meet the GHG emission standards. This paper proposes a measure of GHG emissions based on a unit of land rather than the energy provided by a biofuel pathway utilizing only one feedstock. A hectare of corn thus provides two feedstocks for the biofuel pathway considered here; corn grain is used for production of ethanol while corn stover is subjected to fast pyrolysis for production of biochar and bio-oil. The bio-oil is then subsequently upgraded to a fuel suitable for use as a drop in fuel in internal combustion engines. A LCA of this pathway is conducted and it is found that such a pathway generates a 52.1% reduction in GHG emissions. This is a reduction that is sufficient to qualify the combined output of a hectare of corn as an advanced biofuel if the current restriction in EISA were removed.     

Electro-membrane reactor: A powerful tool for green chemical engineering

Electro-membrane reactors use electro-membranes for preferentially diffusive/electrophoretic migration or electroosmotic separation of in-situ reactive products, thereby maximizing the reaction rate and transport efficiencies of the products. These reactors are widely employed in the chemical engineering sectors such as green chemical synthesis, biorefining, electrocatalytic reduction/oxidation, and water treatment. In this review article, we provide an overview of the recent advances in three categories of electro-membrane reactors in chemical engineering sectors from three categories: (1) Electro-membrane reactors based on stacked ion-exchange membranes for resources recovery; (2) Electro-membrane reactors via Faraday reactions on functional anodes/cathodes for substance transformation; and (3) Closed-loop chemical reactions and substance separation via coupling of Faraday reactions and stacked membranes. The increasing demand for low-carbon economy has accelerated the advancement of environmentally friendly chemical engineering and sustainable processes and necessitates the use of electro-membrane processes. The macro perspective provides a timely reference for researchers and engineers.     

An introduction to life cycle assessment with hands-on experiments for biodiesel production and use

This paper describes a hands-on project that introduces first year engineering students to life cycle assessment (LCA) through the comparison of the environmental impact of the production and use of three diesel fuels: petroleum diesel, biodiesel from new vegetable oil, and biodiesel from waste vegetable oil. The purpose of this LCA project was to incorporate life cycle thinking into the engineering design process, to apply the four main steps of LCA (definition and scope, inventory analysis, impact assessment and improvement assessment), and to explore some of the challenges associated with each step. The inventory for biodiesel production (from both new and waste vegetable oils) was based on measurements obtained by the students in laboratory experiments. The fossil diesel production inventory was obtained from the SimaPro^® database. The inventory for the use of all three fuels was obtained from measurements taken during combustion of the fuels in a generator. A cradle-to-grave life cycle analysis was then conducted using SimaPro^® for each fuel. The assessment of learning outcomes indicates a significant increase in conceptual understanding of the four stages of life cycle assessment, and an average gain of over 55% in overall knowledge of life cycle assessment.     

化工产品生命周期设计的理论和方法

生命周期评价(LCA)和生命周期成本分析(LCC)是实现化工产品和过程清洁生产的两大支持工具。分别介绍了生命周期评价和生命周期成本的内涵和特征,提出了产品生命周期设计(LCD)的概念和实施步骤,有助于设计人员做出正确的决策,开发出环境友好、经济节约的产品。     

Environmental assessment of flue gas cleaning processes of municipal solid waste incinerators by means of the life cycle assessment approach

Life cycle assessment (LCA) is an environmental assessment tool generally applied to products but also to processes. Features of the LCA of processes are presented in this paper. This approach was used to compare two flue gas cleaning processes: the typical wet-type process and the new transported droplets column process. The LCA result shows that the global environmental burden is similar between the two processes, which confirms the viability of the transported droplets column. The distribution of the environmental burden, however, is different between the two processes. The weak points of the transported droplets column are the pollution transfer from air to water and a larger volume to stabilize. Its strong point: it is more efficient in capturing dust particles and toxic pollutants. This process could be improved from an environmental standpoint by adding an electrostatic filter upstream of the transported droplets column to capture the particles. The laboratory results of the transported droplets column need, however, to be confirmed at a larger scale.     

能源和化工系统的全生命周期评价和可持续性研究

在资源和能源日趋紧缺的背景下,开拓替代能源和新的化工产品技术路线势在必行。然而,目前对各种新技术方案的基础数据和系统分析比较薄弱,对产业布局和生态环境的长期影响有待深入研究。对近年来研究资源/能源化工复杂系统的建模、模拟、结构优化和系统集成问题的进展进行综述,运用过程系统投入产出分析的理论和方法,建立化工产品技术路线的全生命周期分析模型与集成的框架平台,研究资源、能源、技术、经济、环境等多因素综合优化评价问题。以煤气化合成气衍生的煤化工系统为基础案例,专门论述了在产品路线规划和过程合成中,集成优化、全生命周期评价和可持续性的研究进展。目标在于推进"技术-经济-环境-产业发展"多属性、多目标、多尺度系统集成的基础理论研究和技术创新。     

Design and assessment of a project-based learning in a laboratory for integrating knowledge and improving engineering design skills

Mechanical Design is a subject usually included in Chemical Engineering Degrees. In this work, we present the application of a project-based learning to the lab in two different engineering degrees, in of one the most time-consuming and difficult subjects of their programs. These two degrees, Mechanical and Chemical engineering degrees, were selected in order to compare the learning outcomes and satisfaction with the activity in the degree more related to mechanical concepts and the Chemical engineering degree. Moreover, to enhance students’ enthusiasm and motivation, these sessions included an innovative manufacturing technology, 3D printing, and digital image correlation (DIC). Before each practical session, the students are encouraged to watch an online video with the fundamental aspects. In order to assess the success of this methodology, after finishing the lab sessions, the students answered a non-formal quantitative survey. The results showed that the proposed project-based learning had the ability to help integrating the knowledge and improve the skills included in the main competences. Although these results are encouraging, there are still parts of the lab activity that should be improve in order to make the activity less time consuming and the most difficult part being easier for the students.     

Integrated project-based learning (IPBL) implementation for first year chemical engineering student: DIY hydraulic jack project

Implementation of student-centered learning has shown wide global acceptance within institutes of higher learning. Some methods, such as active learning, project-based learning, problem-based learning, and experiential-based learning, have significantly impacted the students’ understanding of a particular subject. However, students will still have problems integrating the materials learned from one course to other courses. Thus, this is where the proposed initiative comes in. This paper discusses the implementation of integrated project-based learning (IPBL) to assist students in integrating the knowledge gained from one course to the other for first-year chemical engineering students of Universiti Teknologi PETRONAS. The mapping of assessments and learning domains to the learning activities are also shown in detail. This study was conducted on two courses offered in the same semester, namely, Principles of Chemical Engineering and Chemical Engineering Fluid Mechanics, in January 2019. A total of 214 students grouped in 43 teams were asked to develop a Do-It-Yourself (DIY) hydraulic jack, which uses the fundamentals taught in these two courses. The results show that 100 % student was able to come up with a working prototype within 5 weeks and 90 % of the students agree that the initiative increased their understanding in chemical engineering fundamentals and developed their leadership, problem-solving, communications and time management skills.     

Perspectives of quantum computing for chemical engineering

Quantum computing has been attracting public attention recently. This interest is driven by the advancements in hardware, software, and algorithms required for its successful usage and the promise that it entails the potential acceleration of computational tasks compared to classical computing. This perspective article presents a short review on quantum computing, how this computational approach solves problems, and three fields that quantum computing can potentially impact the most while relevant to chemical engineering: computational chemistry, optimization, and machine learning. Here, we present a series of chemical engineering applications, the developments, potential improvements with respect to classical computing, and challenges that quantum computing faces for each of these fields. This article intends to provide a clear picture of the challenges and potential advantages that quantum technology may yield for chemical engineering, together with an invitation for our colleagues to join us in the adoption and development of quantum computing.     

Life cycle assessment and environmental profile evaluation of lead-free piezoelectrics in comparison with lead zirconate titanate

The prohibition of lead in many electronic components and devices due to its toxicity has reinvigorated the race to develop substitutes for lead zirconate titanate (PZT) based mainly on the potassium sodium niobate (KNN) and sodium bismuth titanate (NBT). However, before successful transition from laboratory to market, critical environmental assessment of all aspects of their fabrication and development must be carried out in comparison with PZT. Given the recent findings that KNN is not intrinsically ‘greener’ than PZT, there is a tendency to see NBT as the solution to achieving environmentally lead-free piezoelectrics competitive with PZT. The lower energy consumed by NBT during synthesis results in a lower overall environmental profile compared to both PZT and KNN. However, bismuth and its oxide are mainly the by-product of lead smelting and comparison between NBT and PZT indicates that the environmental profile of bismuth oxide surpasses that of lead oxide across several key indicators, especially climate change, due to additional processing and refining steps which pose extra challenges in metallurgical recovery. Furthermore, bismuth compares unfavourably with lead due to its higher energy cost of recycling. The fact that roughly 90–95% of bismuth is derived as a by-product of lead smelting also constitutes a major concern for future upscaling. As such, NBT and KNN do not offer absolute competitive edge from an environmental perspective in comparison to PZT. The findings in this work have global practical implications for future Restriction of Hazardous Substances (RoHS) legislation for piezoelectric materials and demonstrate the need for a holistic approach to the development of sustainable functional materials.     

Implementing humanistic view via pass-through game style in teaching: A case study in teaching chemical engineering principles for undergraduates

The humanistic view has a far-reaching influence on education. This work presents an innovative pass-through game style teaching approach to improve the quality of classroom teaching in the rapid development of higher education in China, and creating a model for classroom teaching with a humanistic view. A case study in teaching “Chemical Engineering Principles 2” for undergraduate students in Quzhou University is presented, and great improvement in students’ tests and national competition results, and their satisfaction have been demonstrated. Through the pass-through game style teaching, individual attention for students in big class can be realized.     

Energy in chemical manufacturing processes: gate‐to‐gate information for life cycle assessment

Gate‐to‐gate process energy for 86 chemical manufacturing processes is presented. The estimation of the process energy follows design‐based methodology. Results show that the gate‐to‐gate process energy for half of organic chemicals ranges from 0 to 4 MJ per kg, and for half of inorganic chemicals ranges from ?1 to 3 MJ per kg. The main energy source in both organic and inorganic processes is steam energy followed by potential recovered energy. In organic chemicals, the fractions of heating oil and electricity use are relatively low, but these fractions are higher in the inorganic chemicals than in the organic chemicals. Furthermore, about 50% of the energy consumed in chemical processes is used for purifying the product, byproduct or recycled stream, which indicates that there are large opportunities for improving the process energy in chemical processes. The information presented in this study is very important for those in the life cycle assessment community in order for them to identify inaccurate information or information not based on actual process design. However, the range for the entire range of chemicals is very substantial and thus reflects the need of the life cycle inventory to separately evaluate the chemistry and degree of purity for chemical products. Copyright © 2003 Society of Chemical Industry     

Life Cycle Analysis: Assessment of Technologies for Droplet Separation – A Case Study

For the assessment of separation technologies from an ecological and economic perspective, a case study was performed to investigate the influence of entrainment on energy and resource demand of a single apparatus and on a single production process. Taking the example of the Rectisol process, the influence of droplet entrainment on individual separation equipment as well as on the process as a whole was identified via flowsheet simulation. Based on the calculated mass and energy balances, an LCA and LCC approach was used for the quantification of the entrainment influence.     

Selective thermal recycling for graphene growth on natural substrates: A comparative study on life cycle assessment,energy consumption,and mechanical performance in recompounding

Manufacturing of carbon-based materials from waste thermoplastics is a keystone to reduce adverse environmental impacts. There are numerous attempts for sustainable graphene manufacturing from various waste sources by thermal treatment but there is no clear distinction on the effective conversion process by addressing reliable CO₂ footprints. This study provides a comprehensive benchmarking study on the conversion of waste polypropylene plastics coming from yogurt containers into graphene on the substrate of talc by applying two upcycling techniques of catalytic carbonization (CC) and flash pyrolysis (FP) by comparing energy and speed of the processes and a dimensional stability and physical characteristics of the produced graphene substances by adopting a comparative life cycle assessment. FP led to the sphericalization of graphenes due to fast dehydration, cross-linking, and carbonization of aromatic structures. On the other hand, gradual heating in CC caused the formation of tubular-like graphene structures. In addition, FP became advantageous by resulting in 52% of CO₂ emission compared with CC process. On the other hand, graphenes separated from talcs exhibited a remarkable 70% reduction in global warming potential compared with conventional graphene production from graphite. In order to complete the value chain and circularity, the mechanical performance of two different hybrid additives produced by selective thermal recycling in recompounding with copolymer polypropylene was examined, and additives from CC enhanced the flexural and tensile properties two times better than the one from FP. With this study, it becomes possible to compare analysis of graphene growth on natural substrates by exploring life cycle assessment, energy consumption, and mechanical performance with selective thermal recycling and recompounding.     

Cleaner production of cellulose nanocrystals and calcium sulfate whiskers: Process design and life cycle assessment

The commercialization of cellulose nanocrystals (CNCs) is currently limited by its environmental impact of high water consumption and brine wastewater generation. Here, a combined process integrating the production of CNCs and calcium sulfate whiskers (CSWs) was proposed to achieve complete utilization of the waste acid, and the corresponding environmental performance was evaluated by life cycle assessment (LCA). Accordingly, we prepared fibrous CSWs with an average length of 309 μm and an average aspect ratio of 57 under optimum conditions. The LCA results demonstrated the superior environmental performance of the combined process, especially for CNC production, and the impact values reduced by 45.6% on average. Moreover, the cost of producing 20 g of CNCs decreased from 3.04 CNY (traditional process) to 1.66 CNY (combined process). Therefore, this combined production process is eco-efficient and economically scalable for the industrial production of CNCs.     

The life and death of gc: The changeover to si and the declining use of gc in chemical engineering textbooks

Thirty years ago, an editorial on metrology in the March 1971 issue of AlChE Journal noted the following: “Recognizing the inevitable, the AlChE Journal will require that all papers submitted after July 1, 1971 conform in notation to the SI System (Système International d'Unités)”. This decision was the starting point for the gradual introduction of the use of the SI System in chemical engineering textbooks, at a substitute for the preceding British System. As a consequence, the use of the g_c conversion factor has been also diminishing, gradually but at a slower pace In this paper, the changeover to SI and the declining use of g_c in chemical engineering textbooks is analyzed. Firstly, some representative books published before 1971 are studied. Secondly, a special analysis is devoted to transport phenomena books. Finally, a few but significant books published since 1971, have been selected in order to carry out the analysis of the changeover to SI System and the evolution of the use of g_c