Industrial ecology

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Industrial ecology (IE) is the study of material and energy flows through industrial systems. The global industrial economy can be modelled as a network of industrial processes that extract resources from the Earth and transform those resources into by-products, products and services which can be bought and sold to meet the needs of humanity. Industrial ecology seeks to quantify the material flows and document the industrial processes that make modern society function. Industrial ecologists are often concerned with the impacts that industrial activities have on the environment, with use of the planet's supply of natural resources, and with problems of waste disposal. Industrial ecology is a young but growing multidisciplinary field of research which combines aspects of engineering, economics, sociology, toxicology and the natural sciences.

Contents

Industrial ecology has been defined as a "systems-based, multidisciplinary discourse that seeks to understand emergent behavior of complex integrated human/natural systems". [1] The field approaches issues of sustainability by examining problems from multiple perspectives, usually involving aspects of sociology, the environment, economy and technology. [2] [3] The name comes from the idea that the analogy of natural systems should be used as an aid in understanding how to design sustainable industrial systems. [4]

Overview

Example of industrial symbiosis. Waste steam from a waste incinerator (right) is piped to an ethanol plant (left) where it is used as in input to their production process. IndustrialSymbiosisWasteHeatExchange.png
Example of industrial symbiosis. Waste steam from a waste incinerator (right) is piped to an ethanol plant (left) where it is used as in input to their production process.

Industrial ecology is concerned with the shifting of industrial process from linear (open loop) systems, in which resource and capital investments move through the system to become waste, to a closed loop system where wastes can become inputs for new processes.

Much of the research focuses on the following areas: [5]

Industrial ecology seeks to understand the way in which industrial systems (for example a factory, an ecoregion, or national or global economy) interact with the biosphere. Natural ecosystems provide a metaphor for understanding how different parts of industrial systems interact with one another, in an "ecosystem" based on resources and infrastructural capital rather than on natural capital. It seeks to exploit the idea that natural systems do not have waste in them to inspire sustainable design.

Along with more general energy conservation and material conservation goals, and redefining related international trade markets and product stewardship relations strictly as a service economy, industrial ecology is one of the four objectives of Natural Capitalism. This strategy discourages forms of amoral purchasing arising from ignorance of what goes on at a distance and implies a political economy that values natural capital highly and relies on more instructional capital to design and maintain each unique industrial ecology.

History

View of Kalundborg Eco-industrial Park View from Asnaes power station Kalundborg Denmark.jpg
View of Kalundborg Eco-industrial Park

Industrial ecology was popularized in 1989 in a Scientific American article by Robert Frosch and Nicholas E. Gallopoulos. [6] Frosch and Gallopoulos' vision was "why would not our industrial system behave like an ecosystem, where the wastes of a species may be resource to another species? Why would not the outputs of an industry be the inputs of another, thus reducing use of raw materials, pollution, and saving on waste treatment?" [4] A notable example resides in a Danish industrial park in the city of Kalundborg. Here several linkages of byproducts and waste heat can be found between numerous entities such as a large power plant, an oil refinery, a pharmaceutical plant, a plasterboard factory, an enzyme manufacturer, a waste company and the city itself. [7] Another example is the Rantasalmi EIP in Rantasalmi, Finland. While this country has had previous organically formed EIP's, the park at Rantasalmi is Finland's first planned EIP.

The scientific field Industrial Ecology has grown quickly in recent years. The Journal of Industrial Ecology (since 1997), the International Society for Industrial Ecology (since 2001), and the journal Progress in Industrial Ecology (since 2004) give Industrial Ecology a strong and dynamic position in the international scientific community. Industrial Ecology principles are also emerging in various policy realms such as the concept of the circular economy that is being promoted in China. Although the definition of the circular economy has yet to be formalized, generally the focus is on strategies such as creating a circular flow of materials, and cascading energy flows. An example of this would be using waste heat from one process to run another process that requires a lower temperature. The hope is that strategies such as this will create a more efficient economy with fewer pollutants and other unwanted by-products. [8]

Principles

One of the central principles of Industrial Ecology is the view that societal and technological systems are bounded within the biosphere, and do not exist outside it. Ecology is used as a metaphor due to the observation that natural systems reuse materials and have a largely closed loop cycling of nutrients. Industrial Ecology approaches problems with the hypothesis that by using similar principles as natural systems, industrial systems can be improved to reduce their impact on the natural environment as well. The table shows the general metaphor.

Biosphere Technosphere

IE examines societal issues and their relationship with both technical systems and the environment. Through this holistic view , IE recognizes that solving problems must involve understanding the connections that exist between these systems, various aspects cannot be viewed in isolation. Often changes in one part of the overall system can propagate and cause changes in another part. Thus, you can only understand a problem if you look at its parts in relation to the whole. Based on this framework, IE looks at environmental issues with a systems thinking approach. A good IE example with these societal impacts can be found at the Blue Lagoon in Iceland. The Lagoon uses super-heated water from a local geothermal power plant to fill mineral-rich basins that have become recreational healing centers. In this sense the industrial process of energy production uses its wastewater to provide a crucial resource for the dependent recreational industry.

Take a city for instance. A city can be divided into commercial areas, residential areas, offices, services, infrastructures, and so forth. These are all sub-systems of the 'big city' system. Problems can emerge in one sub-system, but the solution has to be global. Let's say the price of housing is rising dramatically because there is too high a demand for housing. One solution would be to build new houses, but this will lead to more people living in the city, leading to the need for more infrastructure like roads, schools, more supermarkets, etc. This system is a simplified interpretation of reality whose behaviors can be 'predicted'.

In many cases, the systems IE deals with are complex systems. Complexity makes it difficult to understand the behavior of the system and may lead to rebound effects. Due to unforeseen behavioral change of users or consumers, a measure taken to improve environmental performance does not lead to any improvement or may even worsen the situation.

Moreover, life cycle thinking is also a very important principle in industrial ecology. It implies that all environmental impacts caused by a product, system, or project during its life cycle are taken into account. In this context life cycle includes

The transport necessary between these stages is also taken into account as well as, if relevant, extra stages such as reuse, remanufacture, and recycle. Adopting a life cycle approach is essential to avoid shifting environmental impacts from one life cycle stage to another. This is commonly referred to as problem shifting. For instance, during the re-design of a product, one can choose to reduce its weight, thereby decreasing use of resources. It is possible that the lighter materials used in the new product will be more difficult to dispose of. The environmental impacts of the product gained during the extraction phase are shifted to the disposal phase. Overall environmental improvements are thus null.

A final important principle of IE is its integrated approach or multidisciplinarity . IE takes into account three different disciplines: social sciences (including economics), technical sciences and environmental sciences. The challenge is to merge them into a single approach.

Examples

The Kalundborg industrial park is located in Denmark. This industrial park is special because companies reuse each other's waste (which then becomes by-products). For example, the Energy E2 Asnæs Power Station produces gypsum as a by-product of the electricity generation process; this gypsum becomes a resource for the BPB Gyproc A/S which produces plasterboards. [7] This is one example of a system inspired by the biosphere-technosphere metaphor: in ecosystems, the waste from one organism is used as inputs to other organisms; in industrial systems, waste from a company is used as a resource by others.

Apart from the direct benefit of incorporating waste into the loop, the use of an eco-industrial park can be a means of making renewable energy generating plants, like Solar PV, more economical and environmentally friendly. In essence, this assists the growth of the renewable energy industry and the environmental benefits that come with replacing fossil-fuels. [9]

Additional examples of industrial ecology include:

Tools

PeoplePlanetProfitModeling

Future directions

The ecosystem metaphor popularized by Frosch and Gallopoulos [4] has been a valuable creative tool for helping researchers look for novel solutions to difficult problems. Recently, it has been pointed out that this metaphor is based largely on a model of classical ecology, and that advancements in understanding ecology based on complexity science have been made by researchers such as C. S. Holling, James J. Kay, [24] and further advanced in terms of contemporary ecology by others. [25] [26] [27] [28] For industrial ecology, this may mean a shift from a more mechanistic view of systems, to one where sustainability is viewed as an emergent property of a complex system. [29] [30] To explore this further, several researchers are working with agent based modeling techniques. [31] [32]

Exergy analysis is performed in the field of industrial ecology to use energy more efficiently. [33] The term exergy was coined by Zoran Rant in 1956, but the concept was developed by J. Willard Gibbs. In recent decades, utilization of exergy has spread outside physics and engineering to the fields of industrial ecology, ecological economics, systems ecology, and energetics.

Other examples

An example of industrial ecology both in practice and in potential is the Burnside Cleaner Production Centre in Burnside, Nova Scotia. They play a role in facilitating the 'greening' of over 1200 businesses that are located in Burnside, Eastern Canada's largest industrial park. The creation of waste exchange is a big part of what they work towards, which will promote strong industrial ecology relationships. [34]

Onsan Industrial Park is a case-study program intended to serve as an example of policies and practices relevant to pursuing a green growth model of development. The potential benefits of the EIP model are being shown in the Republic of Korea, where more than 1,000 businesses from a wide range of industries call the Ulsan Mipo and Onsan Industrial Park in South Korea home. This park is South Korea's industrial capital because it has more than 100,000 jobs. [35]

A common practice for water waste management systems is to use the left over "sludge" as fertilizer. The waste water contains lots of phosphorus and nitrogen which are valuable chemicals to use in fertilizer. [36]

Gjenge makers ltd is another example of industrial ecology. The company takes discarded plastics and makes them into bricks. Gjenge makers receives the leftover plastic waste from packaging factories and recycling facilities and sells the pavers. [37]

See also

Related Research Articles

<span class="mw-page-title-main">Recycling</span> Converting waste materials into new products

Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on its ability to reacquire the properties it had in its original state. It is an alternative to "conventional" waste disposal that can save material and help lower greenhouse gas emissions. It can also prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, reducing energy use, air pollution and water pollution.

<span class="mw-page-title-main">Ecological economics</span> Interdependence of human economies and natural ecosystems

Ecological economics, bioeconomics, ecolonomy, eco-economics, or ecol-econ is both a transdisciplinary and an interdisciplinary field of academic research addressing the interdependence and coevolution of human economies and natural ecosystems, both intertemporally and spatially. By treating the economy as a subsystem of Earth's larger ecosystem, and by emphasizing the preservation of natural capital, the field of ecological economics is differentiated from environmental economics, which is the mainstream economic analysis of the environment. One survey of German economists found that ecological and environmental economics are different schools of economic thought, with ecological economists emphasizing strong sustainability and rejecting the proposition that physical (human-made) capital can substitute for natural capital.

<span class="mw-page-title-main">Waste management</span> Activities and actions required to manage waste from its source to its final disposal

Waste management or waste disposal includes the processes and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment, and disposal of waste, together with monitoring and regulation of the waste management process and waste-related laws, technologies, and economic mechanisms.

<span class="mw-page-title-main">Life-cycle assessment</span> Methodology for assessing environmental impacts

Life cycle assessment (LCA), also known as life cycle analysis, is a methodology for assessing environmental impacts associated with all the stages of the life cycle of a commercial product, process, or service. For instance, in the case of a manufactured product, environmental impacts are assessed from raw material extraction and processing (cradle), through the product's manufacture, distribution and use, to the recycling or final disposal of the materials composing it (grave).

<span class="mw-page-title-main">Zero waste</span> Philosophy that encourages the redesign of resource life cycles so that all products are reused

Zero waste, or waste minimization, is a set of principles focused on waste prevention that encourages redesigning resource life cycles so that all products are repurposed and/or reused. The goal of the movement is to avoid sending trash to landfills, incinerators, oceans, or any other part of the environment. Currently 9% of global plastic is recycled. In a zero waste system, all materials are reused until the optimum level of consumption is reached.

<span class="mw-page-title-main">Reuse</span> Using again

Reuse is the action or practice of using an item, whether for its original purpose or to fulfill a different function. It should be distinguished from recycling, which is the breaking down of used items to make raw materials for the manufacture of new products. Reuse – by taking, but not reprocessing, previously used items – helps save time, money, energy and resources. In broader economic terms, it can make quality products available to people and organizations with limited means, while generating jobs and business activity that contribute to the economy.

Precycling is the practice of reducing waste by attempting to avoid buying items which will generate waste into home or business. The U.S. Environmental Protection Agency (EPA) also cites that precycling is the preferred method of integrated solid waste management because it cuts waste at its source and therefore trash is eliminated before it is created. According to the EPA, precycling is also characterized as a decision-making process on the behalf of the consumer because it involves making informed judgments regarding a product's waste implications. The implications that are taken into consideration by the consumer include: whether a product is reusable, durable, or repairable; made from renewable or non-renewable resources; over-packaged; and whether or not the container is reusable.

Material flow analysis (MFA), also referred to as substance flow analysis (SFA), is an analytical method to quantify flows and stocks of materials or substances in a well-defined system. MFA is an important tool to study the bio-physical aspects of human activity on different spatial and temporal scales. It is considered a core method of industrial ecology or anthropogenic, urban, social and industrial metabolism. MFA is used to study material, substance, or product flows across different industrial sectors or within ecosystems. MFA can also be applied to a single industrial installation, for example, for tracking nutrient flows through a waste water treatment plant. When combined with an assessment of the costs associated with material flows this business-oriented application of MFA is called material flow cost accounting. MFA is an important tool to study the circular economy and to devise material flow management. Since the 1990s, the number of publications related to material flow analysis has grown steadily. Peer-reviewed journals that publish MFA-related work include the Journal of Industrial Ecology, Ecological Economics, Environmental Science and Technology, and Resources, Conservation, and Recycling.

<span class="mw-page-title-main">Textile recycling</span> Method of reusing or reprocessing used clothing, fibrous material and rags

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<span class="mw-page-title-main">Upcycling</span> Recycling waste into products of higher quality

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<span class="mw-page-title-main">Industrial symbiosis</span>

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<span class="mw-page-title-main">Ecological design</span> Design approach sensitive to environmental impacts

Ecological design or ecodesign is an approach to designing products and services that gives special consideration to the environmental impacts of a product over its entire lifecycle. Sim Van der Ryn and Stuart Cowan define it as "any form of design that minimizes environmentally destructive impacts by integrating itself with living processes." Ecological design can also be defined as the process of integrating environmental considerations into design and development with the aim of reducing environmental impacts of products through their life cycle.

The establishment of industrial ecology as field of scientific research is commonly attributed to an article devoted to industrial ecosystems, written by Frosch and Gallopoulos, which appeared in a 1989 special issue of Scientific American. Industrial ecology emerged from several earlier ideas and concepts, some of which date back to the 19th century.

Environmentally sustainable design is the philosophy of designing physical objects, the built environment, and services to comply with the principles of ecological sustainability and also aimed at improving the health and comfort of occupants in a building. Sustainable design seeks to reduce negative impacts on the environment, the health and well-being of building occupants, thereby improving building performance. The basic objectives of sustainability are to reduce the consumption of non-renewable resources, minimize waste, and create healthy, productive environments.

<span class="mw-page-title-main">Circular economy</span> Production model to minimise wastage and emissions

A circular economy is a model of resource production and consumption in any economy that involves sharing, leasing, reusing, repairing, refurbishing, and recycling existing materials and products for as long as possible. The concept aims to tackle global challenges such as climate change, biodiversity loss, waste, and pollution by emphasizing the design-based implementation of the three base principles of the model. The three principles required for the transformation to a circular economy are: designing out waste and pollution; keeping products and materials in use, and regenerating natural systems." CE is defined in contradistinction to the traditional linear economy. The idea and concepts of a circular economy have been studied extensively in academia, business, and government over the past ten years. It has been gaining popularity because it can help to minimize carbon emissions and the consumption of raw materials, open up new market prospects, and, principally, increase the sustainability of consumption.

<span class="mw-page-title-main">Nutrient cycle</span> Set of processes exchanging nutrients between parts of a system

A nutrient cycle is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyclic. Mineral cycles include the carbon cycle, sulfur cycle, nitrogen cycle, water cycle, phosphorus cycle, oxygen cycle, among others that continually recycle along with other mineral nutrients into productive ecological nutrition.

Resource recovery is using wastes as an input material to create valuable products as new outputs. The aim is to reduce the amount of waste generated, thereby reducing the need for landfill space, and optimising the values created from waste. Resource recovery delays the need to use raw materials in the manufacturing process. Materials found in municipal solid waste, construction and demolition waste, commercial waste and industrial wastes can be used to recover resources for the manufacturing of new materials and products. Plastic, paper, aluminium, glass and metal are examples of where value can be found in waste.

<span class="mw-page-title-main">Cotton recycling</span>

Cotton recycling is the process of converting cotton fabric into fibers that can be reused into other textile products.

Environmental systems analysis (ESA) is a systematic and systems based approach for describing human actions impacting on the natural environment to support decisions and actions aimed at perceived current or future environmental problems. Impacts of different types of objects are studied that ranges from projects, programs and policies, to organizations, and products. Environmental systems analysis encompasses a family of environmental assessment tools and methods, including life cycle assessment (LCA), material flow analysis (MFA) and substance flow analysis (SFA), and environmental impact assessment (EIA), among others.

Waste valorization, beneficial reuse, beneficial use, value recovery or waste reclamation is the process of waste products or residues from an economic process being valorized, by reuse or recycling in order to create economically useful materials. The term comes from practices in sustainable manufacturing and economics, industrial ecology and waste management. The term is usually applied in industrial processes where residue from creating or processing one good is used as a raw material or energy feedstock for another industrial process. Industrial wastes in particular are good candidates for valorization because they tend to be more consistent and predictable than other waste, such as household waste.

References

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