Recycling
Courtesy : en.wikipedia.org
Recycling is the process of converting waste materials into new materials and objects. The recovery of energy from waste materials is often included in this concept. The recyclability of a material depends on its ability to reacquire the properties it had in its original state.[1] 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 (from incineration) and water pollution (from landfilling).
Recycling is a key component of modern waste reduction and is the third component of the “Reduce, Reuse, and Recycle” waste hierarchy.[2][3] It promotes environmental sustainability by removing raw material input and redirecting waste output in the economic system.[4] There are some ISO standards related to recycling, such as ISO 15270:2008 for plastics waste and ISO 14001:2015 for environmental management control of recycling practice.
Recyclable materials include many kinds of glass, paper, cardboard, metal, plastic, tires, textiles, batteries, and electronics. The composting and other reuse of biodegradable waste—such as food and garden waste—is also a form of recycling.[5] Materials for recycling are either delivered to a household recycling center or picked up from curbside bins, then sorted, cleaned, and reprocessed into new materials for manufacturing new products.
In ideal implementations, recycling a material produces a fresh supply of the same material—for example, used office paper would be converted into new office paper, and used polystyrene foam into new polystyrene. Some types of materials, such as metal cans, can be remanufactured repeatedly without losing their purity.[6] With other materials, this is often difficult or too expensive (compared with producing the same product from raw materials or other sources), so “recycling” of many products and materials involves their reuse in producing different materials (for example, paperboard). Another form of recycling is the salvage of constituent materials from complex products, due to either their intrinsic value (such as lead from car batteries and gold from printed circuit boards), or their hazardous nature (e.g. removal and reuse of mercury from thermometers and thermostats).
History
Origins
Recycling has been a common practice for most of human history with recorded advocates as far back as Plato in the fourth century BC.[citation needed] During periods when resources were scarce, archaeological studies of ancient waste dumps show less household waste (such as ash, broken tools, and pottery), implying that more waste was recycled in place of new material.[7] However, archaeological artefacts made from recyclable material, such as glass or metal, may neither be the original object nor resemble it, with the consequence that a successful ancient recycling economy can become invisible when recycling is synonymous with re-melting rather than reuse.[8]
In pre-industrial times, there is evidence of scrap bronze and other metals being collected in Europe and melted down for continuous reuse.[9] Paper recycling was first recorded in 1031 when Japanese shops sold repulped paper.[10][11] In Britain dust and ash from wood and coal fires was collected by “dustmen” and downcycled as a base material for brick making. These forms of recycling were driven by the economic advantage of obtaining recycled materials instead of virgin material, and the need for waste removal in ever-more-densely populated areas.[7] In 1813, Benjamin Law developed the process of turning rags into “shoddy” and “mungo” wool in Batley, Yorkshire, which combined recycled fibers with virgin wool.[12] The West Yorkshire shoddy industry in towns such as Batley and Dewsbury lasted from the early 19th century to at least 1914.
Industrialization spurred demand for affordable materials. In addition to rags, ferrous scrap metals were coveted as they were cheaper to acquire than virgin ore. Railroads purchased and sold scrap metal in the 19th century, and the growing steel and automobile industries purchased scrap in the early 20th century. Many secondary goods were collected, processed and sold by peddlers who scoured dumps and city streets for discarded machinery, pots, pans, and other sources of metal. By World War I, thousands of such peddlers roamed the streets of American cities, taking advantage of market forces to recycle post-consumer materials into industrial production.[13]
Manufacturers of beverage bottles, including Schweppes,[14] began offering refundable recycling deposits in Great Britain and Ireland around 1800. An official recycling system with refundable deposits for bottles was established in Sweden in 1884, and for aluminum beverage cans in 1982; it led to recycling rates of 84–99%, depending on type. (Glass bottles can be refilled around 20 times.[15])
Wartime
American poster from World War II
British poster from World War II
Remnants of iron fence bars in York Whip-Ma-Whop-Ma-Gate. Such public property fences were sawed for the iron and recycled during World War II.
New chemical industries created in the late 19th century both invented new materials (e.g. Bakelite in 1907) and promised to transform valueless into valuable materials. Proverbially, you could not make a silk purse of a sow’s ear—until the US firm Arthur D. Little published in 1921 “On the Making of Silk Purses from Sows’ Ears”, its research proving that when “chemistry puts on overalls and gets down to business […] new values appear. New and better paths are opened to reach the goals desired.”[16]
Recycling—or “salvage”, as it was then usually known—was a major issue for governments during World War II, where financial constraints and significant material shortages made it necessary to reuse goods and recycle materials.[17] These resource shortages caused by the world wars, and other such world-changing events, greatly encouraged recycling.[18][17] It became necessary for most homes to recycle their waste, allowing people to make the most of what was available. Recycling household materials also meant more resources were left available for war efforts.[17] Massive government campaigns, such as the National Salvage Campaign in Britain and the Salvage for Victory campaign in the United States, occurred in every fighting nation, urging citizens to donate metal, paper, rags, and rubber as a patriotic duty.
Post-World War II
A considerable investment in recycling occurred in the 1970s due to rising energy costs.[19] Recycling aluminium uses only 5% of the energy of virgin production. Glass, paper and other metals have less dramatic but significant energy savings when recycled.[20]
Although consumer electronics have been popular since the 1920s, recycling them was almost unheard of until early 1991.[21] The first electronic waste recycling scheme was implemented in Switzerland, beginning with collection of old refrigerators, then expanding to cover all devices.[22] When these programs were created, many countries couldn’t deal with the sheer quantity of e-waste, or its hazardous nature, and began to export the problem to developing countries without enforced environmental legislation. (For example, recycling computer monitors in the United States costs 10 times more than in China.) Demand for electronic waste in Asia began to grow when scrapyards found they could extract valuable substances such as copper, silver, iron, silicon, nickel, and gold during the recycling process.[23] The 2000s saw a boom in both the sales of electronic devices and their growth as a waste stream: In 2002, e-waste grew faster than any other type of waste in the EU.[24] This spurred investment in modern automated facilities to cope with the influx, especially after strict laws were implemented in 2003.[25][26][27][28]
As of 2014, the European Union had about 50% of world share of waste and recycling industries, with over 60,000 companies employing 500,000 people and a turnover of €24 billion.[29] EU countries are mandated to reach recycling rates of at least 50%; leading countries are already at around 65%. The overall EU average was 39% in 2013[30] and is rising steadily, to 45% in 2015.[31][32]
In 2015, the United Nations General Assembly set 17 Sustainable Development Goals. Goal 12, Responsible Consumption and Production, specifies 11 targets “to ensure sustainable consumption and production patterns”.[33] The fifth target, Target 12.5, is defined as substantially reducing waste generation by 2030, indicated by the National Recycling Rate.
In 2018, changes in the recycling industry have sparked a global “crisis”. On 31 December 2017, China announced its “National Sword” policy, setting new standards for imports of recyclable material and banning materials deemed too “dirty” or “hazardous”. The new policy caused drastic disruptions in the global recycling market, and reduced the prices of scrap plastic and low-grade paper. Exports of recyclable materials from G7 countries to China dropped dramatically, with many shifting to countries in southeast Asia. This generated significant concern about the recycling industry’s practices and environmental sustainability. The abrupt shift caused countries to accept more materials than they could process, and raised fundamental questions about shipping waste from developed countries to countries with few environmental regulations—a practice that predated the crisis.[34]
Legislation
Supply
For a recycling program to work, a large, stable supply of recyclable material is crucial. Three legislative options have been used to create such supplies: mandatory recycling collection, container deposit legislation, and refuse bans. Mandatory collection laws set recycling targets for cities, usually in the form that a certain percentage of a material must be diverted from the city’s waste stream by a target date. The city is responsible for working to meet this target.[5]
Container deposit legislation mandates refunds for the return of certain containers—typically glass, plastic and metal. When a product in such a container is purchased, a small surcharge is added that the consumer can reclaim when the container is returned to a collection point. These programs have succeeded in creating an average 80% recycling rate.[35] Despite such good results, the shift in collection costs from local government to industry and consumers has created strong opposition in some areas[5]—for example, where manufacturers bear the responsibility for recycling their products. In the European Union, the WEEE Directive requires producers of consumer electronics to reimburse the recyclers’ costs.[36]
An alternative way to increase the supply of recyclates is to ban the disposal of certain materials as waste, often including used oil, old batteries, tires, and garden waste. This can create a viable economy for the proper disposal of the products. Care must be taken that enough recycling services exist to meet the supply, or such bans can create increased illegal dumping.[5]
Government-mandated demand
Four forms of legislation have also been used to increase and maintain the demand for recycled materials: minimum recycled content mandates, utilization rates, procurement policies, and recycled product labeling.[5]
Both minimum recycled content mandates and utilization rates increase demand by forcing manufacturers to include recycling in their operations. Content mandates specify that a certain percentage of a new product must consist of recycled material. Utilization rates are a more flexible option: Industries can meet their recycling targets at any point of their operations, or even contract out recycling in exchange for tradable credits. Opponents to these methods cite their large increase in reporting requirements, and claim that they rob the industry of flexibility.[5][37]
Governments have used their own purchasing power to increase recycling demand through “procurement policies”. These policies are either “set-asides”, which reserve a certain amount of spending for recycled products; or “price preference” programs that provide larger budgets when recycled items are purchased. Additional regulations can target specific cases: in the United States, for example, the Environmental Protection Agency mandates the purchase of oil, paper, tires and building insulation from recycled or re-refined sources whenever possible.[5]
The final government regulation toward increased demand is recycled product labeling. When producers are required to label their packaging with the amount of recycled material it contains (including the packaging), consumers can make more educated choices. Consumers with sufficient buying power can choose more environmentally conscious options, prompting producers to increase the recycled material in their products and increase demand. Standardized recycling labeling can also have a positive effect on the supply of recyclates when it specifies how and where the product can be recycled.[5]
Recyclates
Glass recovered by crushing only one kind of beer bottle
“Recyclate” is a raw material sent to and processed in a waste recycling plant or materials-recovery facility[38] so it can be used in the production of new materials and products. For example, plastic bottles can be made into plastic pellets and synthetic fabrics.[39]
Quality of recyclate
The quality of recyclates is one of the principal challenges for the success of a long-term vision of a green economy and achieving zero waste. It generally refers to how much of it is composed of target material, versus non-target material and other non-recyclable material.[40] Steel and other metals have intrinsically higher recyclate quality; it is estimated that two-thirds of all new steel comes from recycled steel.[41] Only target material is likely to be recycled, so higher amounts of non-target and non-recyclable materials can reduce the quantity of recycled products.[40] A high proportion of non-target and non-recyclable material can make it more difficult to achieve “high-quality” recycling; and if recyclate is of poor quality, it is more likely to end up being down-cycled or, in more extreme cases, sent to other recovery options or landfilled.[40] For example, to facilitate the remanufacturing of clear glass products, there are tight restrictions for colored glass entering the re-melt process. Another example is the downcycling of plastic, where products such as plastic food packaging are often downcycled into lower quality products, and do not get recycled into the same plastic food packaging.
The quality of recyclate not only supports high-quality recycling, but it can also deliver significant environmental benefits by reducing, reusing, and keeping products out of landfills.[40] High-quality recycling can support economic growth by maximizing the value of waste material.[40] Higher income levels from the sale of quality recyclates can return value significant to local governments, households and businesses.[40] Pursuing high-quality recycling can also promote consumer and business confidence in the waste and resource management sector, and may encourage investment in it.
There are many actions along the recycling supply chain, each of which can affect recyclate quality.[42] Waste producers who place non-target and non-recyclable wastes in recycling collections can affect the quality of final recyclate streams, and require extra efforts to discard those materials at later stages in the recycling process.[42] Different collection systems can induce different levels of contamination. When multiple materials are collected together, extra effort is required to sort them into separate streams and can significantly reduce the quality of the final products.[42] Transportation and the compaction of materials can also make this more difficult. Despite improvements in technology and quality of recyclate, sorting facilities are still not 100% effective in separating materials.[42] When materials are stored outside, where they can become wet, can also cause problems for re-processors. Further sorting steps may be required to satisfactorily reduce the amount of non-target and non-recyclable material.[42]
Recyclate Quality Action Plan (Scotland)
Scotland’s Recyclate Quality Action Plan proposes a number of actions the Scottish Government wants to take to increase the quality of materials collected for recycling and sorted at recovery facilities before it is exported or sold on the reprocessing market.[42] Its objectives are to:[43]
- Increase recyclate quality, and create greater transparency about it.
- Help those contracting with recycling facilities identify what is required of them.
- Ensure compliance with the Waste (Scotland) Regulations 2012.
- Stimulate a household market for quality recyclate.
- Address and reduce issues around waste shipment regulations.
The plan focuses on three key areas, with 14 actions to increase the quality of materials collected, sorted and presented to the processing market in Scotland.[43] These areas are:[42]
- Collection systems and input contamination
- Sorting facilities—material sampling and transparency
- Material quality benchmarking and standards
