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Definition: recycling from Philip's Encyclopedia

Natural and manufactured processes by which substances are broken down and reconstituted. In nature, elemental cycles include the carbon cycle, nitrogen cycle, and hydrological cycle. Natural cyclic chemical processes include the metabolic cycles in the bodies of living organisms. Manufactured recycling includes the use of bacteria to break down organic wastes to harmless, or even beneficial, substances. Large quantities of inorganic waste, such as metal scrap, glass bottles, and building spoil, are recycled.

Summary Article: Recycling
From Encyclopedia of Consumption and Waste

Recycling is an industrial practice in which recyclers collect used or abandoned materials and transform them into their constituent parts to create raw materials for new objects. Though such reprocessing has been around for centuries in artisanal, domestic, and industrial contexts, the term recycling was only coined in 1926 to describe sending partially refined oil back through the refining process. In the 21st century, recycling refers to two distinct but related practices: the industrial system of reprocessing materials and consumer-side recycling motivated by environmental values.


Before the advent of mass production in the industrializing United States, industrial and consumer sides of recycling were inextricably intertwined. Manufacturers depended on consumer waste for many raw materials, including rags for paper and bones for fertilizer and glue. Peddlers and ragmen traded old materials for new goods and allowed people with little cash to obtain consumer items. Thus, as historian Susan Strasser has described, waste and recycling were essential parts of women's domestic economies, especially in rural areas. Disposal and production linked consumers and manufacturers in a symbiotic relationship.

By the end of the 19th century, recycling entered a new paradigm. With increasing urbanization, industrialization, and mass production, household commodities were more affordable and increasingly ubiquitous. Domestic reuse declined, while waste increased and became more concentrated in cities. The first curbside recycling program was introduced in Baltimore in 1874 to manage urban waste and simultaneously create “wealth from waste” by diverting useful materials to industrial processes. By the turn of the century, peddlers and small collectors were replaced with specialized transatlantic businesses that traded in massive quantities of consumer and commercial discards.

This new economy of recycling set the stage for the differentiation between industrial and consumer scales and methods of recycling. From this time to the early 21st century, most items made from recycled materials have drawn their raw materials from industrial scraps or waste from an industry's own production (such as when the sludge created from cutting granite is used in ceramic floor tiles), rather than from consumer discards, which require more time and energy to collect and sort. The known origins and homogeneity of industrial scraps allow reprocessing to become more streamlined and lets producers skip sorting altogether. Motivations for industrial recycling are almost exclusively internal. Industries can and often do save money by not having to pay for additional raw materials or disposal. In the United States, however, the extraction of virgin materials is often subsidized while the recycling industry is not, meaning that virgin materials are often cheaper than their recyclable counterparts.


Recycling can reduce waste, the need for virgin materials, energy consumption, air pollution, and landfill leachates, but the reduction occurs in varying degrees for different processes. Although recycling is usually more environmentally friendly than obtaining and processing virgin material, it is not environmentally benign. First, recycling institutionalizes disposables by treating them after they have been created. Second, while recycling can decrease resources required to make a product, it still necessitates expenditures of energy and virgin materials and produces pollutants, greenhouse gases, and waste. For example, recycling paper involves using water and electricity to separate paper fibers, which must then be de-inked, a process that results in toxic sludge. Recycling can create products that are “downcycled” because they are not as robust as their predecessors; nor are such products usually recyclable (polyurethane plastics, for example, are often turned into asphalt or other end-of-the-line objects). These criticisms come to bear on different materials in different ways. For example, recycling aluminum uses 95 percent less energy than processing bauxite ore and eliminates some of the most environmentally detrimental aspects of mining. Glass and paper recycling have smaller energy savings and use many of the same processes that virgin materials require.


Aluminum recyclables are shredded into smaller pieces and melted. Pure aluminum melts at 600 degrees Celsius, while bauxite ore must be melted at 900 degrees Celsius. Pure aluminum can be melted and remolded without any changes in its material, allowing it to be recycled indefinitely. However, many recyclables, such as soda cans, contain two different aluminums for the body and top and include paint and other coatings. These are burned off as impurities, resulting in air pollution. When the two aluminums are melted together, they result in a weaker downcycled product.

Ferrous Metals (Iron and Steel)

Ferrous metals are the most recycled material in the United States. Their separation from other waste is accomplished with magnets and can be automated. Higher-temperature furnaces can reprocess scraps without adding virgin material, while lower-temperature furnaces can handle around 25 percent scrap. If scrap metal is relatively uncontaminated, it can be recycled without downgrading the final product. Like aluminum, melting metals that have paint or plastics on them results in carcinogenic dioxide emissions.

Paper and Paper Products

Post-consumer paper waste has to be manually sorted into different types, such as paperboard, office paper, and newsprint. Staples are removed with a magnet. The paper is chopped into small pieces and added to water and chemicals. Denser objects that are not paper sink. Any inked or colored papers must be deinked with sodium silicate or sodium hydroxide. Some paper pulp is also bleached. The effluent of the pulping process, called “sludge,” includes chemicals, inks, clay (from glossy paper), plastics, and short paper fibers. This sludge can be toxic and is landfilled or incinerated. When paper is recycled, the fibers break down and become shorter, requiring the input of virgin material. If virgin pulp is not added, the pulp can be used in lower-quality paper products, such as cardboard or newsprint.


Though glass can be recycled indefinitely, raw materials are so inexpensive that economic motivation to recycle glass is low. Glass must be separated by color before it is reprocessed. It is then crushed and melted in a furnace, often with virgin material. It can be blown or molded into new glass products, or it can forgo the melting process and be used in glassphalt (road asphalt made of approximately 30 percent glass cullet). Two pollutants of glass recycling are glass dust, which can include carcinogenic silica, and air pollution from burning impurities.


Plastics include a wide range of resin polymers that must be cleaned and sorted for different processes (the numbers on the bottom of plastic containers are resin identifiers and do not denote whether or not the object is recyclable). Not all plastics are recyclable. Thermoplastics, which make up the majority of 21st-century plastics, are recycled by shredding, heating, and forcing the material through a die that makes long thin strands of plastic. The strands are cut into pellets, which are shipped as raw materials to manufacturers. Thermosetting plastics, including polyurethane and epoxy, cannot be remelted once they are cured and are not recycled into new plastic. They are usually chopped or ground and used as fillers in asphalt or insulation. Finally, biodegradable plastics, most of which are created by using starches to adhere fine plastic strands together, are not recyclable.

Electronic Waste and Other Materials

Electronic waste (e-waste) includes discarded computers, cell phones, televisions, and other electronic devices. Direct disposal is frequently banned because e-waste contains toxic materials, including lead, cadmium, mercury, and brominated flame retardants, which can leach in landfills. In the United States, e-waste is crushed or shredded, then plastics, glass, and metals (such as copper, silver, gold, tin, iron, and aluminum) are separated using magnets, water currents, and screens. However, because of high costs and environmental regulations, most U.S. e-waste is exported to countries with less-stringent labor and environmental laws. Sorting is done by hand, and components are frequently burned to obtain valuable metal parts. Guiye City, China, one of the largest e-waste recycling sites in the world, is notorious for its polluted soil and water and the poor health of its inhabitants.

Batteries, rubber, textiles, wood, biodegradable waste (including sewage), construction and demolition waste, and other nonferrous metals such as copper and lead are also recycled.

Recycling Culture and Participation

Since the 1960s in the United States, consumer-side recycling, or “blue-binning,” has increased in popularity and has come to symbolize an act of environmental responsibility. Within popular culture, recycling has come to signify a range of environmental activities that deal with waste beyond collecting recyclables for industrial reprocessing, including reuse or repurposing, such as weaving purses out of plastic bags. The universal recycling symbol was created for the first Earth Day in the United States in 1970 and continues to promote curbside recycling in the 21st century. The chasing arrows symbolize continuity within a finite entity and are part of a larger environmental rhetoric about resource scarcity, stewardship of the Earth, and the immorality of wasting.

Environmental responsibility is now the dominant frame within which to understand and encourage recycling. Some scholars, such as Gaye Hawkins, have described this ubiquitous environmental framing as a monopoly of interpretation. Within consumer recycling, the diversion rate, or recycling rate, refers to the number of recyclable materials separated from regular municipal solid waste. The diversion rate is measured by weighing collected recyclables over all waste generated (recyclables and garbage). While diversion rates do not measure how many recyclables remain in the waste stream, they are often expressed as a percent. The national recycling rate in the United States hovers just over 30 percent, though this percentage varies by locality and material. Furthermore, each municipality may or may not include commercial waste, lawn waste, and construction and demolition waste in its figures. A myriad of strategies exists for increasing consumer diversion rates, including laws, fines, bottle bills, and pay-by-weight trash collection.

Environmental Movements

There are several environmental movements that marry the industrial processes of recycling with popular notions of environmental stewardship. These movements tend to advocate 100-percent or near-100-percent recycling rates for consumers and industry—a scenario that would involve systematically changing how goods are designed, created, distributed, and reprocessed. Zero waste is a philosophy based on the lack of waste in nature. As a philosophy, the zero waste movement has overarching statements about the role and ideal uses of waste and recycling, but it does not make technical recommendations for achieving these goals, nor does it comment on the state of 21st-century recycling processes, all of which produce waste.

In comparison, the cradle-to-cradle model is based on specific biomemetric techniques of redesign and recycling. The founders, Michael Braungart and William McDonough, a chemist and an architect, respectively, work with businesses to ensure that all products are either “technical nutrients” (100-percent recyclable, nontoxic, and designed to avoid downcycling) or “biological nutrients” (100-percent compostable). The zero waste movement and the cradle-to-cradle model, as well as other criticisms of industrial recycling, posit that recycling has potential to radically increase environmental benefits if changes become more systematic and include the design and planning of both domestic and industrial waste, rather than apprehending a fraction of waste after it has been created.

See Also:

Packaging and Product Containers, Recyclable Labels, Recyclable Products, Recycled Content, Recycling Behaviors, Sustainable Waste Management, Waste Reclamation Service

Further Readings
  • Ackerman, Frank Why Do We Recycle: Markets, Values, and Public Policy. Washington, DC: Island Press, 1997.
  • Grossman, Elizabeth High Tech Trash: Digital Devices, Hidden Toxics, and Human Health. Washington, DC: Island Press, 2006.
  • McDonough, William and Braungart, Michael Cradle to Cradle: Remaking the Way We Make Things. New York: North Point Press, 2002.
  • Strasser, Susan Waste and Want: A Social History of Trash. New York: Metropolitan Books, 1999.
  • Zimring, Carl A. Cash for Your Trash: Scrap Recycling in America. New Brunswick, NJ: Rutgers University Press, 2005.
  • Liboiron, Max
    New York University New York University
    Copyright © 2012 by SAGE Publications, Inc.

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