Urban mining

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An urban mine is the stockpile of rare metals in the discarded waste electrical and electronic equipment (WEEE) of a society. [1] Urban mining is the process of recovering these rare metals through mechanical and chemical treatments. In 1997, recycled gold accounted for approximately 20% of the 2700 tons of gold supplied to the market. [2]

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The name was coined in the 1980s by Professor Hideo Nanjyo of the Research Institute of Mineral Dressing and Metallurgy at Tohoku University and the idea has gained significant traction in Japan (and in other parts of Asia) in the 21st century. [3] [4]

Research published by the Japanese government's National Institute of Materials Science in 2010 estimated that there were 6,800 tonnes of gold recoverable from used electronic equipment in Japan. [5]

The term, urban mining, has been expanded in common use to include the recovery of building materials from buildings. This means that materials can be removed from a building in various stages from the point it is deemed that the building is to be removed at end-of-life, or renovated, retrofitted, or remodeled. Without affecting the major structure, equipment, fixtures, furnishings, finishes, and even non-structural components, like windows, doors, and divider walls, can be removed, when permitted, for their value in reuse or recycling or upcycling as raw materials into new products.

Additionally, at the end-of-life of a building, demolition and disposal have been the established process of removal of buildings and their materials, but recycling of major materials, such as steel and concrete, have become common. Beyond that, there is the burgeoning industry of deconstruction of buildings, which is the careful dismantling of a building for its components and elements, all the resources within that can be reused (which is ideal), or recycled. It is estimated that as much as 95% of a typical American house can be reused or recycled, given access to a variety of means of processing (gypsum board, lumber, etc.) and - importantly - exposure of these materials to willing purchasers.

From the World Economic Forum, November 22, 2023, "What is urban mining – and why do we need to do more of it?" https://www.weforum.org/agenda/2023/11/urban-mining-circular-economy-ewaste/

"Another strong use case is for waste materials from demolition or construction. Around 850 million tons of construction and demolition waste were created by Europe alone in 2020 – more than a third of all waste generated in the region."

From Metabolic - Merlijn Blok - Updated and rewritten on 28/03/2024 - "From Buildings to Resources: The Role of Urban Mining in Circular Cities" https://www.metabolic.nl/news/urban-mining-and-circular-construction/

"Why do we extract, produce, and transport scarce primary materials from mines around the world, when there are abundant secondary sources throughout our cities?"

Yes, why?

By salvaging and repurposing these materials, urban mining helps reduce the demand for new resources, minimizes waste, and promotes sustainable practices in the construction industry. This practice aims to reduce the need for extracting raw materials from natural resources, minimize waste, and promote sustainability by recycling and repurposing materials found in urban environments. Urban mining of building materials contributes to resource conservation, environmental protection, and the circular economy by extracting value from existing would-be-waste streams.

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">Scrap</span> Recyclable materials left over from manufactured products after their use

Scrap consists of recyclable materials, usually metals, left over from product manufacturing and consumption, such as parts of vehicles, building supplies, and surplus materials. Unlike waste, scrap has monetary value, especially recovered metals, and non-metallic materials are also recovered for recycling. Once collected, the materials are sorted into types — typically metal scrap will be crushed, shredded, and sorted using mechanical processes.

<span class="mw-page-title-main">Deconstruction (building)</span>

In the context of physical construction, deconstruction is the selective dismantlement of building components, specifically for reuse, repurposing, recycling, and waste management. It differs from demolition where a site is cleared of its building by the most expedient means. Deconstruction has also been defined as "construction in reverse". Deconstruction requires a substantially higher degree of hands-on labor than does traditional demolition, but as such provides a viable platform for unskilled or unemployed workers to receive job skills training. The process of dismantling structures is an ancient activity that has been revived by the growing fields of sustainable and green building.

<span class="mw-page-title-main">Concrete recycling</span> Re-use of rubble from demolished concrete structures

Concrete recycling is the use of rubble from demolished concrete structures. Recycling is cheaper and more ecological than trucking rubble to a landfill. Crushed rubble can be used for road gravel, revetments, retaining walls, landscaping gravel, or raw material for new concrete. Large pieces can be used as bricks or slabs, or incorporated with new concrete into structures, a material called urbanite.

<span class="mw-page-title-main">Electronic waste</span> Discarded electronic devices

Electronic waste describes discarded electrical or electronic devices. It is also commonly known as waste electrical and electronic equipment (WEEE) or end-of-life (EOL) electronics. Used electronics which are destined for refurbishment, reuse, resale, salvage recycling through material recovery, or disposal are also considered e-waste. Informal processing of e-waste in developing countries can lead to adverse human health effects and environmental pollution. The growing consumption of electronic goods due to the Digital Revolution and innovations in science and technology, such as bitcoin, has led to a global e-waste problem and hazard. The rapid exponential increase of e-waste is due to frequent new model releases and unnecessary purchases of electrical and electronic equipment (EEE), short innovation cycles and low recycling rates, and a drop in the average life span of computers.

<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.

<span class="mw-page-title-main">Aluminium recycling</span> Reuse of scrap aluminium

Aluminium recycling is the process in which secondary commercial aluminium is created from scrap or other forms of end-of-life or otherwise unusable aluminium. It involves re-melting the metal, which is cheaper and more energy-efficient than the production of virgin aluminium by electrolysis of alumina (Al2O3) refined from raw bauxite by use of the Bayer and Hall–Héroult processes.

Landfill mining and reclamation (LFMR) is a process which excavates and processes solid wastes which have previously been landfilled. The process aims to reduce the amount of landfill mass encapsulated within the closed landfill and/or temporarily remove hazardous material to allow protective measures to be taken before the landfill mass is replaced. In the process, mining recovers valuable recyclable materials, a combustible fraction, soil, and landfill space. The aeration of the landfill soil is a secondary benefit with regard to the landfill's future use. The combustible fraction is useful for power generation. The overall appearance of the landfill mining procedure is a sequence of processing machines laid out in a functional conveyor system. The operating principle is to excavate, sieve and sort the landfill material.

<span class="mw-page-title-main">Construction waste</span> Unwanted material produced directly or incidentally by the construction industries

Construction waste or debris is any kind of debris from the construction process. Different government agencies have clear definitions. For example, the United States Environmental Protection Agency EPA defines construction and demolition materials as “debris generated during the construction, renovation and demolition of buildings, roads, and bridges.” Additionally, the EPA has categorized Construction and Demolition (C&D) waste into three categories: non-dangerous, hazardous, and semi-hazardous.

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

Upcycling, also known as creative reuse, is the process of transforming by-products, waste materials, useless, or unwanted products into new materials or products perceived to be of greater quality, such as artistic value or environmental value.

<span class="mw-page-title-main">Waste</span> Unwanted or unusable materials

Waste are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor economic value. A waste product may become a by-product, joint product or resource through an invention that raises a waste product's value above zero.

<span class="mw-page-title-main">Demolition waste</span> Waste debris from destruction of buildings, roads, bridges, or other structures

Demolition waste is waste debris from destruction of buildings, roads, bridges, or other structures. Debris varies in composition, but the major components, by weight, in the US include concrete, wood products, asphalt shingles, brick and clay tile, steel, and drywall. There is the potential to recycle many elements of demolition waste.

Recycling can be carried out on various raw materials. Recycling is an important part of creating more sustainable economies, reducing the cost and environmental impact of raw materials. Not all materials are easily recycled, and processing recyclable into the correct waste stream requires considerable energy. Some particular manufactured goods are not easily separated, unless specially process therefore have unique product-based recycling processes.

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

Mobile phone recycling describes the waste management of mobile phones, to retrieve materials used in their manufacture. Rapid technology change, low initial cost, and planned obsolescence have resulted in a fast-growing surplus, which contributes to the increasing amount of electronic waste around the globe.

<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.

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">Non-ferrous extractive metallurgy</span> Metallurgy process

Non-ferrous extractive metallurgy is one of the two branches of extractive metallurgy which pertains to the processes of reducing valuable, non-iron metals from ores or raw material. Metals like zinc, copper, lead, aluminium as well as rare and noble metals are of particular interest in this field, while the more common metal, iron, is considered a major impurity. Like ferrous extraction, non-ferrous extraction primarily focuses on the economic optimization of extraction processes in separating qualitatively and quantitatively marketable metals from its impurities (gangue).

<span class="mw-page-title-main">Recycling in Australia</span> Method of waste management in Australia

Recycling in Australia is a widespread, and comprehensive part of waste management in Australia, with 60% of all waste collected being recycled. Recycling is collected from households, commercial businesses, industries and construction. Despite its prominence, household recycling makes up only a small part (13%) of Australia's total recycling. It generally occurs through kerbside recycling collections such as the commingled recycling bin and food/garden organics recycling bin, drop-off and take-back programs, and various other schemes. Collection and management of household recycling typically falls to local councils, with private contractors collecting commercial, industrial and construction recycling. In addition to local council regulations, legislation and overarching policies are implemented and managed by the state and federal governments.

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

Closed-loop recycling is the process by which a product or material can be used and then turned into a new product indefinitely without losing its properties during the recycling process.

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

  1. Kuroda & Ueda 2011, p. 197.
  2. Renner, Hermann; Schlamp, Günther; Hollmann, Dieter; Lüschow, Hans Martin; Tews, Peter; Rothaut, Josef; Dermann, Klaus; Knödler, Alfons; Hecht, Christian; Schlott, Martin; Drieselmann, Ralf; Peter, Catrin; Schiele, Rainer (2000). "Gold, Gold Alloys, and Gold Compounds". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a12_499. ISBN   3527306730.
  3. Yu et al. 2011, pp. 165–166.
  4. Nakamura 2016, p. 39.
  5. Yu et al. 2011, p. 166.

Sources

  • Kuroda, Kouichi; Ueda, Mitsuyoshi (2011). "Cell surface design for selective recovery of rare metal ions". In Ike, Michihiko; Yamashita, Mitsuo; Soda, Satoshi (eds.). Handbook of Metal Biotechnology: Applications for Environmental Conservation and Sustainability. CRC Press. ISBN   9789814267991.
  • Yu, Jeongsoo; Che, Jia; Omura, Michiaki; Serrona, Kevin Roy B. (2011). "Emerging issues on Urban Mining in Automobile Recycling". In Kumar, Sunil (ed.). Integrated Waste Management. Vol. 2. InTech. ISBN   9789533074474.
  • Nakamura, Takashi (2016). "How to recover minor rare metals from e-scrap". In Neelameggham, Neale; Alam, Shafiq; Oosterhof, Harald; Jha, Animesh; Dreisinger, David; Wang, Shijie (eds.). Rare Metal Technology 2015. Minerals, Metals & Materials. Springer. ISBN   9783319481883.

Further reading