Sustainable engineering: An initiative for chemical engineers (original) (raw)

Green Engineering Education through a U.S. EPA/Academia Collaboration

Environmental Science & Technology, 2003

The need to use resources efficiently and reduce environmental impacts of industrial products and processes is becoming increasingly important in engineering design; therefore, green engineering principles are gaining prominence within engineering education. This paper describes a general framework for incorporating green engineering design principles into engineering curricula, with specific examples for chemical engineering. The framework for teaching green engineering discussed in this paper mirrors the 12 Principles of Green Engineering proposed by Anastas and Zimmerman (Environ. Sci. Technol. 2003, 37, 94A-101A), especially in methods for estimating the hazardous nature of chemicals, strategies for pollution prevention, and approaches leading to efficient energy and material utilization. The key elements in green engineering education, which enlarge the "box" for engineering design, are environmental literacy, environmentally conscious design, and beyond-the-plant boundary considerations.

Guest Editor’s Note: Green Chemical Engineering

Rangsit University, 2016

________________________________________________________________________________________________ Green Chemical Engineering will lead us to a bright, sustainable future. Designers must strive to ensure that all materials and energy inputs and outputs are as inherently nonhazardous as possible. Use your chemical knowledge of properties like boiling point, melting point, freezing point, vapor pressure, and water solubility. In addition chemical engineers must note flammability, explosivity, compressibility, viscosity, and properties that affect heat and mass transfer. These are the starting points when we are designing a new chemical process. We have to do more. Most of us are less familiar with properties related to toxicity to environmental organisms and humans. The engineer must have a systems perspective: i.e., the ability to do mass and energy balances. Don't just look at your laboratory bench or pilot plant process. Look at your systems-factory scale-whole industrial park scale. Designers need to select chemicals or materials whose properties will not cause harm to the environment or to people. With the right choice of chemicals and materials, a designer can control how much energy is required and the form of that energy; e.g., heating, cooling, light, microwave, pressure, etc. In terms of putting toxics into the environment energy matters as much as the choice of chemicals. It is better to prevent waste than to treat or clean up waste after it is formed. A central tenets of green technologies is to make only the amount that is needed for a process. From a business perspective, this makes absolute sense. Think out the new process or procedure that you want to try. How much of everything goes into making your product? Do you need all of these things? If you have to heat the reaction, a large pot of solvent is going to need a lot of heat. Less solvent would need less heat. The engineer might design a process in which the reaction is run to low conversion, a separation is achieved to recover the product, and the unused reactant is recycled back to the reactor, allowing higher overall conversion. Separation and purification operations should be designed to minimize energy consumption and materials use. Industrial separation processes are very energy intensive. Historically, for liquid and condensable gases, multistage distillation has been the workhorse process. Many bulk organic chemicals involve distillation, which adds significantly to their production CO 2 footprints. Thus, avoiding distillation, making distillation more efficient, and searching for alternatives to distillation are very important. One technology that has broken the hold of distillation in a large scale application is reverse osmosis membrane separation for water desalination. Reverse osmosis uses mechanical pressure to overcome the osmotic pressure exerted by the salt solution and thereby push the water through a selective skin. As calculated by the change of free energy of mixing, the theoretical energy to de-mix water and salt is approximately 1 kWh/m 3 of water, the current best membrane technologies have a real energy cost of 4.0 kWh/m 3 and thermal "distillation" type technologies use on the order of 50 kWh/m 3. When you see caparisons like this, you know the old, familiar technologies may need updating. Products, processes and systems should be designed to maximize mass, energy, space, and time efficiency. It is simplicity that will allow us, as a society, to become more sustainable. In the past, there was no consideration regarding the complexity of the reaction, and material, energy and production requirements that will be needed to take this chemical reaction from the bench to the pilot plant to production. As

Green Engineering is the Best Fit to Approach Nature's Engineering Benchmark

The population and consumption is continuing to grow while non-renewable fossil fuels and other raw materials are depleted at ever increasing rates. A technical approach to address these issues using engineering design and analysis called the green engineering has emerged. Green Engineering transforms existing engineering disciplines and practices to those that lead to sustainability. Green Engineering incorporates development and implementation of products, processes, and systems that meet technical and cost objectives while protecting human health and welfare and elevates the protection of the biosphere as a criterion in engineering solutions. The green engineering must be close to natural engineering system to be sustainable. The use of free energy, prevent waste generation and waste prevention & waste minimization strategies. Waste minimization can be achieved in an efficient way by focusing on 'reduce', followed by 'reuse' & then 'recycle' and finally 'energy recovery'. Twelve basic principles of green engineering along with ten rules to follow in any of the multi-disciplinary have been discussed. A few case studies have been presented to corroborate the benefits of green engineering with sustainable development.

New trends for design towards sustainability in chemical engineering: Green engineering

Chemical Engineering Journal, 2007

A broad review of disciplines and technologies concerning the last-decade-advances and state-of-the-art in the understanding and application of sustainability from a Chemical Engineering viewpoint is presented. Up to now it was hard to find useful sustainability criteria and ready-to-use guidance tools for the design of products, processes and production systems. Fortunately, in the last decade a range of practices and disciplines have appeared transforming the way in which traditional disciplines were conceived. Firstly, a review of the concept of sustainability and its significance for the chemical and process industry is presented. Then, several inspiring philosophies and disciplines which are the basis of the new trends in design are briefly reviewed, namely, The Natural Step, Biomimicry, Cradle to Cradle, Getting to Zero Waste, Resilience Engineering, Inherently Safer Design, Ecological Design, Green Chemistry and Self-Assembly. The core of the manuscript is a deep review of what has been done in Green Engineering so far, including its main definitions and scope of application, different guiding principles, frameworks for design and legislative aspects. A range of illustrative industrial applications and several tools oriented to GE are analysed. Finally, some educational considerations and training opportunities are included, providing education at academic and university levels allows for the creation of a critical mass of engineers and scientists to foster green engineering and sustainable development in the future.

Sustainability in chemical engineering education: Identifying a core body of knowledge

AIChE Journal, 2012

The quality of modern life depends on the availability of vast amounts of energy and an array of products provided by the chemical industry. Chemical processes provide products and materials used in health care, consumer products, transportation, agriculture, food processing, electronic materials, and construction. Highly energetic, globally transportable fuels are an essential element of global transportation and distribution systems. Yet, these same chemical processes and fuel systems that provide products essential for modern economies, like all engineered systems, consume resources and have environmental impacts. Growing demand for energy, food and materials have put increasing pressure on air and water, arable land, and raw materials. Concern over the ability of natural resources and environmental systems to support the needs and wants of global populations, now and in the future, is part of an emerging awareness of the concept of sustainability. Sustainability is a powerful, yet abstract, concept. The most commonly employed definition of sustainability is that of the Brundtland Commission report-development that meets the needs of the present generation without compromising the ability of future generations to meet their needs (1). However, a search on the definition of sustainability will return many variations on this basic concept. For example, the 2006 National Research Council report on Sustainability in the Chemical Industry (2) defines sustainability as "a path forward that allows humanity to meet current environmental and human health, economic, and societal needs without compromising the progress and success of future generations". In engineering, incorporating a concern about sustainability into products, processes, technology systems, and services generally means integrating environmental, economic, and social factors in the evaluation of projects and designs. This can be referred to as "sustainable engineering", but other terms have also been used; green engineering, design for environment, pollution prevention, eco-efficiency and a variety of other terms. To grasp the magnitude of the sustainability challenge, it is useful to invoke a conceptual equation that is generally attributed to Ehrlich and Holdren (3). The equation relates impact (I), to population (P), affluence (A), and technology (T). I = P * A * T This conceptual relationship, commonly referred to as the IPAT equation, suggests that impacts, which could be energy use, materials use, or emissions, are the product of the population (number of people), the affluence of the population (generally expressed as gross domestic product of a nation or region, divided by the number of people in the nation or region), and the Perspective AIChE Journal

Sustainability—The next chapter

Chemical Engineering Science, 2006

In the last decade significant progress has been made in recognising and understanding the issues in sustainability. Much remains to be done because the science that underlies sustainability is still far from exact. Given the natural abilities of chemical engineers with systems analysis, balances and modelling, there is a key role for chemical engineering science to play in its development. An integrated approach requires addressing cascading levels of sustainability objectives. The levels are global objectives, industry strategy, enterprise targets, specific targets and individual actions/measurement outcomes. We need to consider the reality of the cascade effect-is it possible for global objectives to cascade all the way down to individual actions and what will be the effect of each of the steps between? Exploration of the existing metrics and sustainability systems in relation to these cascading levels reveals that there is no single approach that can address both global responsibilities and enterprise and company interests. It is time for a framework for sustainability to be developed that can be used across all scales of application. Indicators that address all levels of sustainability goals will enable a paradigm shift, allowing us to move beyond individual problems and to offer options on the pathway to the ultimate solution. Without these indicators it is difficult to translate our broad goals into decision-making processes. Reliable indicators would also assist companies to resist the pressures that work against sustainability, for example, those from investors for short-term returns. Chemical engineering has a history of embracing new disciplines and has a special role to play in the change process. An understanding at the micro and molecular levels and the integration of this knowledge into macro systems will be integral to the shift towards process engineering addressing the sustainability framework. Breakthroughs in greenhouse gas reduction, climate change prevention and process redesign will require a strong base of chemical engineering science. I see opportunities for chemical engineers to play a leadership role by collaborating with other industries in building critical mass and contributing to step change beyond best practice, by broadening the scope of the discipline and by restructuring chemical engineering education at an individual level.

Environmental Sustainability for Engineers and Applied Scientists

2019

This textbook presents key theoretical approaches to understanding issues of sustainability and environmental management, perfectly bridging the gap between engineering and environmental science. It begins with the fundamentals of environmental modelling and toxicology, which are then used to discuss qualitative and quantitative risk assessment methods, and environmental assessments of product design. It discusses how business and government can work towards sustainability, focusing on managerial and legal tools, before considering ethics and how decisions on environmental management can be made. Students will learn quantitative methods while also gaining an understanding of qualitative, legal, and ethical aspects of sustainability. Practical applications are included throughout, and there are study questions at the end of each chapter. PowerPoint slides and jpegs of all the figures in the book are provided online. This is the perfect textbook on environmental studies for engineerin...