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Editorial overview: Energy and environmental engineering: Energy-water nexus: transition from generic to specific
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ScienceDirect Editorial overview: Energy and environmental engineering: Energy-water nexus: transition from generic to specific Subhas K Sikdar and Rakesh Agrawal Current Opinion in Chemical Engineering 2014, 5:v–vi For a complete overview see the Issue Available online 14th August 2014 http://dx.doi.org/10.1016/j.coche.2014.07.005 2211-3398/Published by Elsevier Ltd.
Subhas K Sikdar National Risk Management Research Laboratory, US Environmental Protection Agency, Cincinnati, OH 45268, USA e-mail: [email protected] Dr. Subhas K Sikdar is the Associate Director for Science for the National Risk Management Research Laboratory of the U.S. EPA in Cincinnati, OH. For 22 years he championed the concepts and methods for clean products and processes for the Agency and in NATO projects and engineering workshops. He is the founder and the coEditor-in-Chief of the international journal, Clean Technologies and Environmental Policy. He currently chairs the Engineers’ Forum for Sustainability and has published more than 80 technical papers in reputed journals, has 27 U.S. patents, and has edited 15 books.
Rakesh Agrawal School of Chemical Engineering, Purdue University, Forney Hall of Chemical Engineering, 480 Stadium Mall Drive, West Lafayette, IN 47907, USA e-mail: [email protected] Rakesh Agrawal is Winthrop E. Stone Distinguished Professor, School of Chemical Engineering, Purdue University. A major thrust of his research is related to energy issues and includes novel processes for fabrication of low-cost solar cells, biomass and liquid fuel conversion, and energy systems analysis. His research further includes synthesis of multicomponent separation configurations including distillation, membrane and adsorption based processes, basic and applied research in gas separations, process development, gas liquefaction and cryogenic processes. He is a recipient of the U.S. National Medal of Technology and Innovation.
www.sciencedirect.com
Vast amounts of research results and opinion pieces accumulated over the recent past on clean water quality and quantity have brought energy-water nexus to the forefront as an important civil society issue. Various environmental, economic, and societal factors are driving this section, such as global warming due to emission of greenhouse gases from energy production, and shrinking clean water reserves resulting from unsustainable water withdrawal, which is turning many parts of human-habited world into waterstressed areas. In simple terms, energy-water nexus means that we need useful energy to produce clean water, especially drinking water, and conversely we need clean water to produce useful energy for doing work, such as providing electricity or raising steam. Other nexuses derived from this concept are being discussed as well, the most prominent of them being energy-water-agriculture nexus. The inter-connectivity of the appropriate sectors of the economy, once unappreciated, is now considered essential to include into the design and analyses of many anthropogenic enterprises to avoid societal ills that could be explained away before as unintended consequences but are now clearly possible to anticipate and avoid by engineering approaches. Production of energy and water for industrial and civic uses may not have been a central focus of chemical engineering, but this discipline typically employs these resources in various chemical conversion processes that produce industrial and consumer goods, and hence examining the dynamics of the nexus has become a research and operational focus in chemical engineering. We know from thermodynamic principles that the total energy of a system is conserved, yet it is the useful energy, called exergy, that is relevant in this nexus parlance. Similarly, the total water content of the globe is the same regardless of the quality of water, but we are mainly concerned about clean water which can be seen as the equivalent of the exergy concept because it is in that form we can make use of water. This concept of water scarcity in the face of abundance was sharply brought into relief in the immortal words of Samuel Taylor Coleridge in his poem, The Rime of the Ancient Mariner: Water, water, everywhere, And all the boards did shrink; Water, water, everywhere, Nor any drop to drink.’’ In the works of engineers, the energy-water nexus is going beyond the statistics of numbers to mathematical analyses of processes that produce energy or water to the design and operation of plants that make useful Current Opinion in Chemical Engineering 2014, 5:v–vi
vi Energy and Environmental engineering
products that improve our standards of living. In this issue we have recruited several papers relevant to chemical engineers, yet not all are written by chemical engineers. Yang and Goodrich examine clean water sustainability from the urban needs and climate change perspectives. They have anchored their analysis on IPCC-predicted climate change and the adaptive needs of protecting the water resources from the regional fallouts. They extend their analysis to the needs of innovative technologies that minimize the use of these precious resources to satisfy both Government policy aims and adequate human needs. Varbanov examines the global water-energy nexus, focusing on the implications of the trade of goods that carry virtual water from one region to another. He points out the frequent mismatch between location of production of water and energy and their use. This mismatch exists both for water and energy, but is more pronounced for water. He argues that since increases in water use amplify the needs for more energy, the same works in reverse. Thus process integration techniques can be used to minimize both in production situation, such as in biofuels. Dodder focuses on the electricity production sector from a systems perspective by considering both fossil and non-fossil means. This article also uses climate change as the backdrop requiring carbon capture and sequestration (CCS) as a necessary element for preventing adverse climate change outcomes, while water use in production situations is minimized. Her analysis similarly points to the need for developing more energy and water efficient technologies. El-Halwagi et al. analyze the application of gas to liquid (GTL) technology, such as Fischer Tropsch approaches to hydraulic fracturing products also in the context of this nexus. Hydraulic fracturing requires large volumes of fresh water for producing the ‘fracking’ liquids endowed with desired properties, and the integration of fracking with GTL presents challenges to waterenergy nexus, especially in arid water-stressed regions. They share some interesting insights into managing this nexus. Gabriel et al. focuses on a specific route to a new technology, gas to liquid processes (GTL) for the production of liquid fuels for transportation needs for water use optimization. Their technique for demonstrating attainment of this aim is process integration which relies on targeting water use reduction and shows how the process system can be modified to realistically reach the goal. Grossmann et al. also reviewed the connection between energy and water consumption within a chemical plant. They argue that reducing energy consumption can often result in freshwater consumption. Thus they emphasize the need for developing methods that will simultaneously optimize both energy and freshwater demand for chemical and petrochemical processes. They present synthesis methods for water networks, especially for biofuel plants, after performing flow sheet optimization with heat integration. They present examples where substantial Current Opinion in Chemical Engineering 2014, 5:v–vi
reduction in freshwater demand is achieved through reuse, waste water treatment and prudent recycles for bioethanol as well as biodiesel productions. These articles are examples of the state-of-the art waste water network synthesis methods. Use of large quantities of water for natural gas production from shale formations (shale gas) in the United States is well known. For shale gas production, the article by Allen discusses the need to balance the potential environmental impact due to associated methane emission with the energy and economic benefits. The global warming potential of methane over a hundred year time horizon is presented. It is followed by telling us the urgency to control methane’s leak within 1–5% of a well’s production. However, it also points to the challenges associated with measuring and monitoring methane leak from a shale gas supply chain. Finally, the article provides us a glimpse of multi-scale combinations of bottom-up and top-down approaches that could be deployed to monitor methane emission during shale gas production and use. Siirola provides us a glimpse of the future global energy supply and demand. He considers various factor such as current global population growth rate, gross domestic product (GDP) of different regions of the world and variation in current energy consumption per GDP along with anticipated energy efficiency improvements to conclude that the total global energy demand may nearly triple by midway of the present century. However, he also points out that this energy consumption could further substantially increase due to water desalination and other water purification needs. Siirola also points out that due to concerns with global warming, use of renewable non-carbon energy sources such as solar wind, etc., will eventually increase. However, a great concern is the intermittent availability of these resources. While batteries are quite efficient for energy storage, there is a need for alternative means of energy storage at GWhr levels due to relatively low storage energy density for batteries. Genc¸er et al. present carbon storage cycles (CSC) that uses cyclic transformation between carbon dioxide and a carbon containing fuel. Thus, when renewable energy is available, carbon dioxide is converted to a fuel and during periods of unavailability, the fuel is converted to carbon dioxide which is then stored as liquid carbon dioxide and electricity is provided to the grid. Such cycles are shown to have storage efficiencies approaching 57% and are quite amenable to chemical engineering principles. Thus the articles in this section deal with energy-water nexus as well as important issues associated with global energy and fresh water demand and supply. They provide us with the issues where we chemical engineers can contribute by developing solutions for this grand challenge of our time. www.sciencedirect.com
ScienceDirect Editorial overview: Energy and environmental engineering: Energy-water nexus: transition from generic to specific Subhas K Sikdar and Rakesh Agrawal Current Opinion in Chemical Engineering 2014, 5:v–vi For a complete overview see the Issue Available online 14th August 2014 http://dx.doi.org/10.1016/j.coche.2014.07.005 2211-3398/Published by Elsevier Ltd.
Subhas K Sikdar National Risk Management Research Laboratory, US Environmental Protection Agency, Cincinnati, OH 45268, USA e-mail: [email protected] Dr. Subhas K Sikdar is the Associate Director for Science for the National Risk Management Research Laboratory of the U.S. EPA in Cincinnati, OH. For 22 years he championed the concepts and methods for clean products and processes for the Agency and in NATO projects and engineering workshops. He is the founder and the coEditor-in-Chief of the international journal, Clean Technologies and Environmental Policy. He currently chairs the Engineers’ Forum for Sustainability and has published more than 80 technical papers in reputed journals, has 27 U.S. patents, and has edited 15 books.
Rakesh Agrawal School of Chemical Engineering, Purdue University, Forney Hall of Chemical Engineering, 480 Stadium Mall Drive, West Lafayette, IN 47907, USA e-mail: [email protected] Rakesh Agrawal is Winthrop E. Stone Distinguished Professor, School of Chemical Engineering, Purdue University. A major thrust of his research is related to energy issues and includes novel processes for fabrication of low-cost solar cells, biomass and liquid fuel conversion, and energy systems analysis. His research further includes synthesis of multicomponent separation configurations including distillation, membrane and adsorption based processes, basic and applied research in gas separations, process development, gas liquefaction and cryogenic processes. He is a recipient of the U.S. National Medal of Technology and Innovation.
www.sciencedirect.com
Vast amounts of research results and opinion pieces accumulated over the recent past on clean water quality and quantity have brought energy-water nexus to the forefront as an important civil society issue. Various environmental, economic, and societal factors are driving this section, such as global warming due to emission of greenhouse gases from energy production, and shrinking clean water reserves resulting from unsustainable water withdrawal, which is turning many parts of human-habited world into waterstressed areas. In simple terms, energy-water nexus means that we need useful energy to produce clean water, especially drinking water, and conversely we need clean water to produce useful energy for doing work, such as providing electricity or raising steam. Other nexuses derived from this concept are being discussed as well, the most prominent of them being energy-water-agriculture nexus. The inter-connectivity of the appropriate sectors of the economy, once unappreciated, is now considered essential to include into the design and analyses of many anthropogenic enterprises to avoid societal ills that could be explained away before as unintended consequences but are now clearly possible to anticipate and avoid by engineering approaches. Production of energy and water for industrial and civic uses may not have been a central focus of chemical engineering, but this discipline typically employs these resources in various chemical conversion processes that produce industrial and consumer goods, and hence examining the dynamics of the nexus has become a research and operational focus in chemical engineering. We know from thermodynamic principles that the total energy of a system is conserved, yet it is the useful energy, called exergy, that is relevant in this nexus parlance. Similarly, the total water content of the globe is the same regardless of the quality of water, but we are mainly concerned about clean water which can be seen as the equivalent of the exergy concept because it is in that form we can make use of water. This concept of water scarcity in the face of abundance was sharply brought into relief in the immortal words of Samuel Taylor Coleridge in his poem, The Rime of the Ancient Mariner: Water, water, everywhere, And all the boards did shrink; Water, water, everywhere, Nor any drop to drink.’’ In the works of engineers, the energy-water nexus is going beyond the statistics of numbers to mathematical analyses of processes that produce energy or water to the design and operation of plants that make useful Current Opinion in Chemical Engineering 2014, 5:v–vi
vi Energy and Environmental engineering
products that improve our standards of living. In this issue we have recruited several papers relevant to chemical engineers, yet not all are written by chemical engineers. Yang and Goodrich examine clean water sustainability from the urban needs and climate change perspectives. They have anchored their analysis on IPCC-predicted climate change and the adaptive needs of protecting the water resources from the regional fallouts. They extend their analysis to the needs of innovative technologies that minimize the use of these precious resources to satisfy both Government policy aims and adequate human needs. Varbanov examines the global water-energy nexus, focusing on the implications of the trade of goods that carry virtual water from one region to another. He points out the frequent mismatch between location of production of water and energy and their use. This mismatch exists both for water and energy, but is more pronounced for water. He argues that since increases in water use amplify the needs for more energy, the same works in reverse. Thus process integration techniques can be used to minimize both in production situation, such as in biofuels. Dodder focuses on the electricity production sector from a systems perspective by considering both fossil and non-fossil means. This article also uses climate change as the backdrop requiring carbon capture and sequestration (CCS) as a necessary element for preventing adverse climate change outcomes, while water use in production situations is minimized. Her analysis similarly points to the need for developing more energy and water efficient technologies. El-Halwagi et al. analyze the application of gas to liquid (GTL) technology, such as Fischer Tropsch approaches to hydraulic fracturing products also in the context of this nexus. Hydraulic fracturing requires large volumes of fresh water for producing the ‘fracking’ liquids endowed with desired properties, and the integration of fracking with GTL presents challenges to waterenergy nexus, especially in arid water-stressed regions. They share some interesting insights into managing this nexus. Gabriel et al. focuses on a specific route to a new technology, gas to liquid processes (GTL) for the production of liquid fuels for transportation needs for water use optimization. Their technique for demonstrating attainment of this aim is process integration which relies on targeting water use reduction and shows how the process system can be modified to realistically reach the goal. Grossmann et al. also reviewed the connection between energy and water consumption within a chemical plant. They argue that reducing energy consumption can often result in freshwater consumption. Thus they emphasize the need for developing methods that will simultaneously optimize both energy and freshwater demand for chemical and petrochemical processes. They present synthesis methods for water networks, especially for biofuel plants, after performing flow sheet optimization with heat integration. They present examples where substantial Current Opinion in Chemical Engineering 2014, 5:v–vi
reduction in freshwater demand is achieved through reuse, waste water treatment and prudent recycles for bioethanol as well as biodiesel productions. These articles are examples of the state-of-the art waste water network synthesis methods. Use of large quantities of water for natural gas production from shale formations (shale gas) in the United States is well known. For shale gas production, the article by Allen discusses the need to balance the potential environmental impact due to associated methane emission with the energy and economic benefits. The global warming potential of methane over a hundred year time horizon is presented. It is followed by telling us the urgency to control methane’s leak within 1–5% of a well’s production. However, it also points to the challenges associated with measuring and monitoring methane leak from a shale gas supply chain. Finally, the article provides us a glimpse of multi-scale combinations of bottom-up and top-down approaches that could be deployed to monitor methane emission during shale gas production and use. Siirola provides us a glimpse of the future global energy supply and demand. He considers various factor such as current global population growth rate, gross domestic product (GDP) of different regions of the world and variation in current energy consumption per GDP along with anticipated energy efficiency improvements to conclude that the total global energy demand may nearly triple by midway of the present century. However, he also points out that this energy consumption could further substantially increase due to water desalination and other water purification needs. Siirola also points out that due to concerns with global warming, use of renewable non-carbon energy sources such as solar wind, etc., will eventually increase. However, a great concern is the intermittent availability of these resources. While batteries are quite efficient for energy storage, there is a need for alternative means of energy storage at GWhr levels due to relatively low storage energy density for batteries. Genc¸er et al. present carbon storage cycles (CSC) that uses cyclic transformation between carbon dioxide and a carbon containing fuel. Thus, when renewable energy is available, carbon dioxide is converted to a fuel and during periods of unavailability, the fuel is converted to carbon dioxide which is then stored as liquid carbon dioxide and electricity is provided to the grid. Such cycles are shown to have storage efficiencies approaching 57% and are quite amenable to chemical engineering principles. Thus the articles in this section deal with energy-water nexus as well as important issues associated with global energy and fresh water demand and supply. They provide us with the issues where we chemical engineers can contribute by developing solutions for this grand challenge of our time. www.sciencedirect.com