Recycling in the United States
Financial implications
Some argue State support for recycling may be more financially expensive in the short term than alternatives such as landfill; recycling efforts in New York City in the USA cost $57 million per year[1]. It is argued that the benefits to society from recycling compensate for any difference in cost. Landfilling waste is an inefficient use of resources, contributes to global warming through the release of methane into the atmosphere and by the pollution of groundwater and waterways. The long term financial costs of remediating pollution caused by landfilling waste are often not taken into consideration.
America Recycles Day
The 11th annual America Recycles day was held on the 15 November 2007. Hundreds of events annually are being held across the country to raise awareness about the importance of recycling and to encourage Americans to sign personal pledges to recycle and buy recycled products.[2][3]
Run by the recycling sector organization National Recycling Coalition, America Recycles Day 2006 is being sponsored nationally by global aluminum company Novelis, stationery firm Staples, waste firm Waste Management Recycle America, the American Beverage Association and the EPA.
Although America may not enjoy much of a reputation for environmentalism on the global stage, in some US cities recycling levels are much higher than, for example, in the UK.[4]
See also
Keep America Beautiful
Recycling in Canada
Recycling in Ireland
International Container Supplier
Busch Systems International Inc.
External links
http://www.OurEarth.org/
http://www.nyc.gov/sanitation
http://www.nyc.gov/nycwasteless
http://www.nyc.gov/nycstuffexchange
http://www.ecyclegroup.org
Ward 49 of the City of Chicago includes most of Rogers Park and parts of West Ridge.
Showing posts with label Recycling. Show all posts
Showing posts with label Recycling. Show all posts
Wednesday, December 12, 2007
Plastic recycling
Plastic recycling
Plastic recycling is the process of recovering scrap or waste plastics and reprocessing the material into useful products, sometimes completely different from their original state. For instance, this could mean melting down polyester soft drink bottles then making model army figures and ammunition.
Before recycling, plastics are sorted according to their resin identification code. PET, for instance, has a resin code of 1.
Obstacles
When compared to glass or metallic materials, plastic poses some unique challenges from a recycling perspective. Chief among them is their low entropy of mixing, which is due to the high molecular weight of large polymer chains. Another way of stating this problem is that, since a macromolecule interacts with its environment along its entire length, its enthalpy of mixing is very, very large compared to that of a small organic molecule with a similar structure; thermal excitations are often not enough to drive such a huge molecule into solution on their own. Due to this uncommon influence of mixing enthalpy, polymers must often be of nearly identical composition in order to mix with one another. To take representative samples from beverage containers, the many aluminium-based alloys all melt into the same liquid phase, but the various copolymer blends of PET from different manufacturers do not dissolve into one another when heated. Instead, they tend to phase-separate, like oil and water. Phase boundaries weaken an item made from such a mixture considerably, meaning that most polymer blends are only useful in a few, very limited contexts.
Another barrier to recycling is the widespread use of dyes, fillers, and other additives in plastics.
The polymer is generally too viscous to economically remove fillers, and would be damaged by many of the processes that could cheaply remove the added dyes. Additives are less widely used in beverage containers and plastic bags, allowing them to be recycled more frequently.
The use of biodegradable plastics is increasing. If some of these get mixed in the other plastics for recycling, the recycled plastic is less valuable.
Many such problems can be solved by using a more elaborate monomer recycling process, in which a condensation polymer essentially undergoes the inverse of the polymerization reaction used to manufacture it. This yields the same mix of chemicals that formed the original polymer, which can be purified and used to synthesize new polymer chains of the same type. Du Pont opened a pilot plant of this type in Cape Fear, North Carolina, to recycle PET by a process of methanolysis, but it closed the plant due to economic pressures.
Another potential option is the conversion of assorted polymers into petroleum by a much less precise thermal depolymerization process. Such a process would be able to accept almost any polymer or mix of polymers, including thermoset materials such as vulcanized rubber tires and the biopolymers in feathers and other agricultural waste. Like natural petroleum, the chemicals produced can be made into fuels as well as polymers. A pilot plant of this type exists in Carthage, Missouri, using turkey waste as a feedstock. See the main article on thermal depolymerization. Gasification is a similar process, but is not technically recycling since polymers are not likely to become the result.
Recently, a process has also been developed in which many kinds of plastic can be used as a carbon source in the recycling of scrap steel. [1]
Yet another process that is gaining ground with startup companies (especially in Australia, United States and Japan) is Heat Compression. The heat compression process takes all unsorted, cleaned plastic in all forms, from soft plastic bags to hard industrial waste, and mixes the load in tumblers (large rotating drums resembling giant clothes dryers). The process generates heat from the friction of the plastic materials rubbing against each other inside the drum, eventually melting all, or most of the material. The materials are then pumped out of the drum through heated pipes into casting moulds. The most obvious benefit to this method is the fact that all plastic is recyclable, not just matching forms. But criticism rises from the energy costs of rotating the drums, and heating the post-melt pipes.
Applications
The most-often recycled plastic, HDPE or number 2, is downcycled into plastic lumber, tables, roadside kerbs, benches, truck cargo liners, trash receptacles, stationery (e.g rulers) and other durable plastic products and is usually in demand. The white plastic "peanuts" used as packing material are often accepted by shipping stores for reuse.
In Israel successful trials have shown that plastic films recovered from mixed municipal waste streams can be recycled into useful products.[2]
Similarly, agricultural plastics such as mulch film, drip tape and silage bags are being diverted from the waste stream and successfully recycled into bulk resin commodities in Labelle, FL.[3]
Historically, these agricultural plastics have primarily been either landfilled or burned on-site in the fields of individual farms.[4]
The environmental benefits of recycling plastic are that it produces less sulphur dioxide, less waste and less carbon dioxide.
Consumers
Plastic recycling rates lag far behind those of other items, such as newspaper (about 80%) and cardboard (about 70%). One reason is that consumers often don’t understand the types of plastics that can be recycled in their area. Types of plastics are assigned a number, which is usually stamped or printed on the bottom of containers and surrounded by a pyramid of arrows. (See the table in Plastic.) Numbers 1, 2, and 6 are the most-often recycled plastics in the United States. Many programs exist in the United States and the reduction of weight in numerous packaging applications has been significant over the last 25 years.
Consumers can find out which plastics are accepted in their local area and how to prepare and transfer them by contacting their local recycling hauler (usually the local city or county solid waste or public works department, or a private company). Generally, paper labels do not need to be removed from plastic bottles or containers, but lids should be thrown away because they typically are made from a type of plastic that is not recyclable. Plastic bottles and containers must be rinsed, squashed, and placed in recycle bins for collection. Plastic grocery bags are often accepted by stores in recycling containers placed near the entranceways. [5]
See also
Recycling of PET Bottles
Scrap
Recycling
Plastic recycling is the process of recovering scrap or waste plastics and reprocessing the material into useful products, sometimes completely different from their original state. For instance, this could mean melting down polyester soft drink bottles then making model army figures and ammunition.
Before recycling, plastics are sorted according to their resin identification code. PET, for instance, has a resin code of 1.
Obstacles
When compared to glass or metallic materials, plastic poses some unique challenges from a recycling perspective. Chief among them is their low entropy of mixing, which is due to the high molecular weight of large polymer chains. Another way of stating this problem is that, since a macromolecule interacts with its environment along its entire length, its enthalpy of mixing is very, very large compared to that of a small organic molecule with a similar structure; thermal excitations are often not enough to drive such a huge molecule into solution on their own. Due to this uncommon influence of mixing enthalpy, polymers must often be of nearly identical composition in order to mix with one another. To take representative samples from beverage containers, the many aluminium-based alloys all melt into the same liquid phase, but the various copolymer blends of PET from different manufacturers do not dissolve into one another when heated. Instead, they tend to phase-separate, like oil and water. Phase boundaries weaken an item made from such a mixture considerably, meaning that most polymer blends are only useful in a few, very limited contexts.
Another barrier to recycling is the widespread use of dyes, fillers, and other additives in plastics.
The polymer is generally too viscous to economically remove fillers, and would be damaged by many of the processes that could cheaply remove the added dyes. Additives are less widely used in beverage containers and plastic bags, allowing them to be recycled more frequently.
The use of biodegradable plastics is increasing. If some of these get mixed in the other plastics for recycling, the recycled plastic is less valuable.
Many such problems can be solved by using a more elaborate monomer recycling process, in which a condensation polymer essentially undergoes the inverse of the polymerization reaction used to manufacture it. This yields the same mix of chemicals that formed the original polymer, which can be purified and used to synthesize new polymer chains of the same type. Du Pont opened a pilot plant of this type in Cape Fear, North Carolina, to recycle PET by a process of methanolysis, but it closed the plant due to economic pressures.
Another potential option is the conversion of assorted polymers into petroleum by a much less precise thermal depolymerization process. Such a process would be able to accept almost any polymer or mix of polymers, including thermoset materials such as vulcanized rubber tires and the biopolymers in feathers and other agricultural waste. Like natural petroleum, the chemicals produced can be made into fuels as well as polymers. A pilot plant of this type exists in Carthage, Missouri, using turkey waste as a feedstock. See the main article on thermal depolymerization. Gasification is a similar process, but is not technically recycling since polymers are not likely to become the result.
Recently, a process has also been developed in which many kinds of plastic can be used as a carbon source in the recycling of scrap steel. [1]
Yet another process that is gaining ground with startup companies (especially in Australia, United States and Japan) is Heat Compression. The heat compression process takes all unsorted, cleaned plastic in all forms, from soft plastic bags to hard industrial waste, and mixes the load in tumblers (large rotating drums resembling giant clothes dryers). The process generates heat from the friction of the plastic materials rubbing against each other inside the drum, eventually melting all, or most of the material. The materials are then pumped out of the drum through heated pipes into casting moulds. The most obvious benefit to this method is the fact that all plastic is recyclable, not just matching forms. But criticism rises from the energy costs of rotating the drums, and heating the post-melt pipes.
Applications
The most-often recycled plastic, HDPE or number 2, is downcycled into plastic lumber, tables, roadside kerbs, benches, truck cargo liners, trash receptacles, stationery (e.g rulers) and other durable plastic products and is usually in demand. The white plastic "peanuts" used as packing material are often accepted by shipping stores for reuse.
In Israel successful trials have shown that plastic films recovered from mixed municipal waste streams can be recycled into useful products.[2]
Similarly, agricultural plastics such as mulch film, drip tape and silage bags are being diverted from the waste stream and successfully recycled into bulk resin commodities in Labelle, FL.[3]
Historically, these agricultural plastics have primarily been either landfilled or burned on-site in the fields of individual farms.[4]
The environmental benefits of recycling plastic are that it produces less sulphur dioxide, less waste and less carbon dioxide.
Consumers
Plastic recycling rates lag far behind those of other items, such as newspaper (about 80%) and cardboard (about 70%). One reason is that consumers often don’t understand the types of plastics that can be recycled in their area. Types of plastics are assigned a number, which is usually stamped or printed on the bottom of containers and surrounded by a pyramid of arrows. (See the table in Plastic.) Numbers 1, 2, and 6 are the most-often recycled plastics in the United States. Many programs exist in the United States and the reduction of weight in numerous packaging applications has been significant over the last 25 years.
Consumers can find out which plastics are accepted in their local area and how to prepare and transfer them by contacting their local recycling hauler (usually the local city or county solid waste or public works department, or a private company). Generally, paper labels do not need to be removed from plastic bottles or containers, but lids should be thrown away because they typically are made from a type of plastic that is not recyclable. Plastic bottles and containers must be rinsed, squashed, and placed in recycle bins for collection. Plastic grocery bags are often accepted by stores in recycling containers placed near the entranceways. [5]
See also
Recycling of PET Bottles
Scrap
Recycling
Tire recycling
Tire recycling
Tire recycling is the process of recycling vehicles tires that are no longer suitable for use on vehicles due to wear or irreparable damage (such as punctures). These tires are among the largest and most problematic sources of waste, due to the large volume produced and their durability. Those same characteristics which make waste tires such a problem also make them one of the most re-used waste materials, as the rubber is very resilient and can be reused in other products. Approximately one tire is discarded per person per year. The U.S.
Environmental Protection Agency reports 290 million scrap tires were generated in 2003.[1] Of the 290 million, 45 million of these scrap tires were used to make automotive and truck tire re-treads.[2] With landfills minimizing their acceptance of whole tires and the health and environmental risks of stockpiling tires, many new markets have been created for scrap tires. Growing markets exist for a majority of scrap tires produced every year, being supported by State and Local Government.
History
Rubber recycling dates back to about the time when industrial rubber manufacturing began. A machine called a Masticator or a "pickle", invented by Thomas Hancock around 1820, which ground up rubber scraps into shreds that could then be mashed into blocks and reused. Due to the high cost of rubber (equal in cost per ounce to silver), starting in 1910 and continuing well into the 20th century, 50% of rubber content was recycled.[3] This type of rubber recycling was very basic and easy, but short-lived. In 1843 Charles Goodyear invented vulcanization, a process of weather proofing rubber by linking all the molecules in a rubber product into one big molecule preventing separation, receiving a patent on June 24, 1844.[4] Since vulcanization links the molecules it is difficult to separate these molecules again to recycle, meaning the product cannot be re-melted.[5] Vulcanized rubber could still be shredded and ground, but had to be mixed with natural rubber to reuse. A shortage of natural rubber caused by the need for tires during World War II, led to the building of synthetic rubber plants around the world in 1945.[6] In the 1960s cheap oil imports and an increased use of synthetic rubber brought down manufacturing costs making the tire and rubber industry's recycled rubber content drop to 20%.[7] Use of synthetic rubber surpasses that of natural rubber for the first time.[8] The 1960s also brought about steel-belted radial tires, which made recycling even more difficult; the steel now would have to be removed after slicing and grinding. A national wave of Tire-Derived Fuel (TDF) development occurs in the mid 1980s, although not recycling, eliminates tires and provides a fuel for utilities. In 1990 markets are shown to exist for 17% of used tires, growing to 78% in 2001 and up to 80.4% in 2003.[9] Due to safety issues, tire industry's recycled rubber content drops to 5-15%, new tires must be manufactured primarily from virgin rubber. The tire recycling industry is currently developing methods of devulcanization or rubber molecule separation by: Pyrolysis, Bacteria, Ultrasound, Thermal, or Mechanical means.
Tire Life Cycle
The tire life cycle can be identified by the following six steps:
1) Product developments and innovations increase tire life, increments of replacement, consumer safety, and reduce tire waste.
2) Proper manufacturing and quality of delivery reduces waste at production.
3) Direct distribution through retailers, reduces inventory time and ensures that the life span and the safety of the products are explained to customers.
4) Consumers use and maintenance choices like tire rotation affect tire wear and safety of operation.
5) Manufacturers and retailers set policies on return, re-tread, and replacement to reduce the waste generated from tires and assume responsibility for taking the ‘tire to its grave’ or to its reincarnation.
6) Recycling tires by developing strategies that combust or process waste into new products, creates viable businesses, and fulfilling public policies.[10].
Landfill Disposal
Tires are not desired at landfills due to their large volumes, 75% void space, which quickly consumes valuable space.[11] Tires can trap methane gases causing them to become buoyant, or ‘bubble’ to the surface. This ‘bubbling’ effect can damage landfill liners that has been installed to help keep landfill contaminants from polluting local surface and ground water.[12] Shredded tires are now being used in landfills, replacing other construction materials, for a light weight backfill in gas venting systems, leachate collection systems, and operational liners. Shredded tire material may also be used to cap, close, or daily cover landfill sites.[13] Scrap tires as a backfill and cover material is also more cost effective, since tires can be shredded on site instead of hauling in other fill materials. In 2003, 38 states banned whole tires from landfills, 35 allowed shredded tires, 11 banned all tires from landfills, 17 allowed processed tires in mono-fills, and 8 states had no restrictions on scrap tires in landfills (Rubber Manufacturers Association, 2003).
Stockpiles and Illegal Dumping
Tire stockpiles create a great health and safety risk. Tire fires can occur easily, burning for months, creating substantial pollution in the air and ground, becoming Superfund cleanup sites. By recycling tires it helps to reduce the number of tires in storage. The United States has decreased the number of waste tires in storage from 700-800 million in 1994, down to 275 million tires in 2004 primarily due to state scrap management programs (Rubber Manufacturers Association 2004). An additional health risk, tire piles provide harborage for vermin and a breeding ground for mosquitoes that may carry diseases. Illegal dumping of scrap tires pollutes ravines, woods, deserts, and empty lots; which has led many states to pass scrap tire regulations requiring proper management. Tire amnesty day events, in which community members can deposit a limited number of waste tires free of charge, can be funded by state scrap tire programs, helping decrease illegal dumping and improper storage of scrap tires.
Ultrasound recycling
High power ultrasound is applied to the cured rubber during extrusion and the high pressure, heat and mechanical energy break the crosslinks which make the extrudate a gum rubber like new material, that can be recurred and molded into new rubber products.
Markets
As of 2003 markets existed for 80.4% of scrap tires, about 233 million tires per year. These markets are for: Tire Derived Fuel (TDF) 44.7% (130 million), Civil Engineering Projects 19.4% (56 million), Ground Rubber turned into molded rubber products 7.8% (18 million), Ground Rubber turned into rubber-modified asphalt (4.3% (12 million), Exported 3.1% (9 million), Cut/Stamped/Punched Products 2.0% (6.5 million), and Agricultural and Misc. uses 1.7% (3 million).[14]
Tire Recycling Supply Chain
The Tire Recycling Supply Chain is divided into three stages:
Collection and processing stage
The number of tires being made available for recycle is growing, as attention and demand for tire derived products increases. In addition, state and government programs exist to clean-up scrap tire stockpiles and illegal dumping sites with a long-term goal of no scrap tires sent to the landfill. The tire processing stage is sorted into four operations: whole tires, stamped (cut) tires, chipped (shredded) tires, and ground (crumb) rubber.
Tire-derived products stage
Second stage of tire recycling involves the production of alternate products for sale. New products derived from waste tires generate more economic activity than combustion or other low multiplier production, while reducing waste stream without generating excessive pollution and emissions from recycling operations.[15].
Tire-derived products
Whole tires can be reused in many different ways. One way, although not recycling, is for a Steel mill to burn the tires for carbon replacement in steel manufacturing. Tires are also bound together and used as different types of barriers such as: collision reduction, erosion control, rainwater runoff, wave action- that protects piers and marshes, and sound barriers between roadways and residences. Entire homes can be built with whole tires by ramming them full of earth and covering them with concrete, known as Earthships.
Some Artificial reefs are built using tires that are bonded together in groups, there is some controversy on how effective tires are as an artificial reef system, an example is The Osborne Reef Project.
Ground up tires even find their way back to your car in the form of automotive parts, like: exhaust hangers, brake pads and shoes, acoustic insulation, and even low percentages go into making new tires.
Distribution and demand stage
For the third stage the production of new products is so dependant on a distribution network and marketing efforts to ensure sales, that transporters and processors of tires are expected to keep focusing on their upstream activity. In order to create new products companies are more likely to merge or link with distributors and retailers to ensure product sales and satisfy customers. Consolidation up and down the tire recycling supply chain must occur to increase the probability of a healthy business. Integrating supply chains can reduce costs, and prices, placing producers closer to their customers. The challenge remaining is to realize supply chain consolidation without increasing prices or decreasing product and service quality. It may be unlikely that companies will keep prices low when consolidation creates larger organizations that take advantage of economies of scale and increased market power.[16].
Environmental Concerns
Due to heavy metals and other pollutants in tires there is a potential risk for the leaching (leachate) of toxins into the groundwater when placed in wet soils. This impact on the environment varies according to the Ph level and conditions of local water and soil. Research has shown that very little leaching occurs when shredded tires are used as light fill material, however limitations have been put on use of this material; each site should be individually assessed determining if this product is appropriate for given conditions.[17]
State and Local Government
State laws and regulations dealing with scrap tires are currently enacted in 48 states. Here are some common features of state programs that deal with scrap tires: source of funding for the program, licensing or registration of scrap tire haulers, processors, and end users, manifests for scrap tire shipments, limitations on who may handle scrap tires, financial assurance requirements for scrap tire handlers, and market development activities.[18] Some state programs are now supported by fees charged to the consumer at purchase or disposal of each tire. These fees sometimes called “tipping fees” help to support recycling costs. When the disposal rates charged to consumers are set high this in turn discourages landfill disposal, a simple solution encouraging more affordable tire recycling programs.
See also
Vulcanization/Devulcanization
Pyrolysis
Recycle
Tire
Rubber
Tire fire
Landfill
Landfill liner
Waste Management
Artificial reef
Re-tread
Katy Trail (Dallas)
Rubber mulch
Mousepad
Underlay
Railroad tie
Rubberized asphalt
External links
Manufacturers Association (RMA)
Environmental Protection Agency (EPA)
Ohio Department of Natural Resources
Tire Derived Product Suppliers, California
International Institute of Synthetic Rubber Producers, Inc.
New Scientist article on a microwave process that turns tires back to oil.
Tire recycling is the process of recycling vehicles tires that are no longer suitable for use on vehicles due to wear or irreparable damage (such as punctures). These tires are among the largest and most problematic sources of waste, due to the large volume produced and their durability. Those same characteristics which make waste tires such a problem also make them one of the most re-used waste materials, as the rubber is very resilient and can be reused in other products. Approximately one tire is discarded per person per year. The U.S.
Environmental Protection Agency reports 290 million scrap tires were generated in 2003.[1] Of the 290 million, 45 million of these scrap tires were used to make automotive and truck tire re-treads.[2] With landfills minimizing their acceptance of whole tires and the health and environmental risks of stockpiling tires, many new markets have been created for scrap tires. Growing markets exist for a majority of scrap tires produced every year, being supported by State and Local Government.
History
Rubber recycling dates back to about the time when industrial rubber manufacturing began. A machine called a Masticator or a "pickle", invented by Thomas Hancock around 1820, which ground up rubber scraps into shreds that could then be mashed into blocks and reused. Due to the high cost of rubber (equal in cost per ounce to silver), starting in 1910 and continuing well into the 20th century, 50% of rubber content was recycled.[3] This type of rubber recycling was very basic and easy, but short-lived. In 1843 Charles Goodyear invented vulcanization, a process of weather proofing rubber by linking all the molecules in a rubber product into one big molecule preventing separation, receiving a patent on June 24, 1844.[4] Since vulcanization links the molecules it is difficult to separate these molecules again to recycle, meaning the product cannot be re-melted.[5] Vulcanized rubber could still be shredded and ground, but had to be mixed with natural rubber to reuse. A shortage of natural rubber caused by the need for tires during World War II, led to the building of synthetic rubber plants around the world in 1945.[6] In the 1960s cheap oil imports and an increased use of synthetic rubber brought down manufacturing costs making the tire and rubber industry's recycled rubber content drop to 20%.[7] Use of synthetic rubber surpasses that of natural rubber for the first time.[8] The 1960s also brought about steel-belted radial tires, which made recycling even more difficult; the steel now would have to be removed after slicing and grinding. A national wave of Tire-Derived Fuel (TDF) development occurs in the mid 1980s, although not recycling, eliminates tires and provides a fuel for utilities. In 1990 markets are shown to exist for 17% of used tires, growing to 78% in 2001 and up to 80.4% in 2003.[9] Due to safety issues, tire industry's recycled rubber content drops to 5-15%, new tires must be manufactured primarily from virgin rubber. The tire recycling industry is currently developing methods of devulcanization or rubber molecule separation by: Pyrolysis, Bacteria, Ultrasound, Thermal, or Mechanical means.
Tire Life Cycle
The tire life cycle can be identified by the following six steps:
1) Product developments and innovations increase tire life, increments of replacement, consumer safety, and reduce tire waste.
2) Proper manufacturing and quality of delivery reduces waste at production.
3) Direct distribution through retailers, reduces inventory time and ensures that the life span and the safety of the products are explained to customers.
4) Consumers use and maintenance choices like tire rotation affect tire wear and safety of operation.
5) Manufacturers and retailers set policies on return, re-tread, and replacement to reduce the waste generated from tires and assume responsibility for taking the ‘tire to its grave’ or to its reincarnation.
6) Recycling tires by developing strategies that combust or process waste into new products, creates viable businesses, and fulfilling public policies.[10].
Landfill Disposal
Tires are not desired at landfills due to their large volumes, 75% void space, which quickly consumes valuable space.[11] Tires can trap methane gases causing them to become buoyant, or ‘bubble’ to the surface. This ‘bubbling’ effect can damage landfill liners that has been installed to help keep landfill contaminants from polluting local surface and ground water.[12] Shredded tires are now being used in landfills, replacing other construction materials, for a light weight backfill in gas venting systems, leachate collection systems, and operational liners. Shredded tire material may also be used to cap, close, or daily cover landfill sites.[13] Scrap tires as a backfill and cover material is also more cost effective, since tires can be shredded on site instead of hauling in other fill materials. In 2003, 38 states banned whole tires from landfills, 35 allowed shredded tires, 11 banned all tires from landfills, 17 allowed processed tires in mono-fills, and 8 states had no restrictions on scrap tires in landfills (Rubber Manufacturers Association, 2003).
Stockpiles and Illegal Dumping
Tire stockpiles create a great health and safety risk. Tire fires can occur easily, burning for months, creating substantial pollution in the air and ground, becoming Superfund cleanup sites. By recycling tires it helps to reduce the number of tires in storage. The United States has decreased the number of waste tires in storage from 700-800 million in 1994, down to 275 million tires in 2004 primarily due to state scrap management programs (Rubber Manufacturers Association 2004). An additional health risk, tire piles provide harborage for vermin and a breeding ground for mosquitoes that may carry diseases. Illegal dumping of scrap tires pollutes ravines, woods, deserts, and empty lots; which has led many states to pass scrap tire regulations requiring proper management. Tire amnesty day events, in which community members can deposit a limited number of waste tires free of charge, can be funded by state scrap tire programs, helping decrease illegal dumping and improper storage of scrap tires.
Ultrasound recycling
High power ultrasound is applied to the cured rubber during extrusion and the high pressure, heat and mechanical energy break the crosslinks which make the extrudate a gum rubber like new material, that can be recurred and molded into new rubber products.
Markets
As of 2003 markets existed for 80.4% of scrap tires, about 233 million tires per year. These markets are for: Tire Derived Fuel (TDF) 44.7% (130 million), Civil Engineering Projects 19.4% (56 million), Ground Rubber turned into molded rubber products 7.8% (18 million), Ground Rubber turned into rubber-modified asphalt (4.3% (12 million), Exported 3.1% (9 million), Cut/Stamped/Punched Products 2.0% (6.5 million), and Agricultural and Misc. uses 1.7% (3 million).[14]
Tire Recycling Supply Chain
The Tire Recycling Supply Chain is divided into three stages:
Collection and processing stage
The number of tires being made available for recycle is growing, as attention and demand for tire derived products increases. In addition, state and government programs exist to clean-up scrap tire stockpiles and illegal dumping sites with a long-term goal of no scrap tires sent to the landfill. The tire processing stage is sorted into four operations: whole tires, stamped (cut) tires, chipped (shredded) tires, and ground (crumb) rubber.
Tire-derived products stage
Second stage of tire recycling involves the production of alternate products for sale. New products derived from waste tires generate more economic activity than combustion or other low multiplier production, while reducing waste stream without generating excessive pollution and emissions from recycling operations.[15].
Tire-derived products
Whole tires can be reused in many different ways. One way, although not recycling, is for a Steel mill to burn the tires for carbon replacement in steel manufacturing. Tires are also bound together and used as different types of barriers such as: collision reduction, erosion control, rainwater runoff, wave action- that protects piers and marshes, and sound barriers between roadways and residences. Entire homes can be built with whole tires by ramming them full of earth and covering them with concrete, known as Earthships.
Some Artificial reefs are built using tires that are bonded together in groups, there is some controversy on how effective tires are as an artificial reef system, an example is The Osborne Reef Project.
- The process of stamping and cutting tires is used in some apparel products, such as sandals and as a road sub-base, by connecting together the cut sidewalls to form a flexible net.
- Chipped and shredded tires are used as Tire Derived Fuel (TDF); once again not recycling, but TDF helps to eliminate tires from our waste stream and produces a fuel source. Also used in civil engineering applications such as: sub grade fill and embankments, backfill for walls and bridge abutments, sub grade insulation for roads, landfill projects, and septic system drain fields
- Ground and crumb rubber, also known as size-reduced rubber, can be used in both paving type projects and in moldable products. These types of paving are: Rubber Modified Asphalt (RMA), Rubber Modified Concrete, and as a substitution for an aggregate. Examples of rubber-molded products are: Carpet padding or underlay, flooring materials, dock bumpers, patio decks, railroad crossing blocks, livestock mats, sidewalks, rubber tiles and bricks, moveable speed bumps, and curbing/edging. Then there is plastic and rubber blend molded products like pallets and railroad ties. Athletic and recreational areas can also be paved with the shock absorbing rubber-molded material. Rubber from tires is sometimes ground into medium-sized chunks and used as rubber mulch.
Ground up tires even find their way back to your car in the form of automotive parts, like: exhaust hangers, brake pads and shoes, acoustic insulation, and even low percentages go into making new tires.
Distribution and demand stage
For the third stage the production of new products is so dependant on a distribution network and marketing efforts to ensure sales, that transporters and processors of tires are expected to keep focusing on their upstream activity. In order to create new products companies are more likely to merge or link with distributors and retailers to ensure product sales and satisfy customers. Consolidation up and down the tire recycling supply chain must occur to increase the probability of a healthy business. Integrating supply chains can reduce costs, and prices, placing producers closer to their customers. The challenge remaining is to realize supply chain consolidation without increasing prices or decreasing product and service quality. It may be unlikely that companies will keep prices low when consolidation creates larger organizations that take advantage of economies of scale and increased market power.[16].
Environmental Concerns
Due to heavy metals and other pollutants in tires there is a potential risk for the leaching (leachate) of toxins into the groundwater when placed in wet soils. This impact on the environment varies according to the Ph level and conditions of local water and soil. Research has shown that very little leaching occurs when shredded tires are used as light fill material, however limitations have been put on use of this material; each site should be individually assessed determining if this product is appropriate for given conditions.[17]
State and Local Government
State laws and regulations dealing with scrap tires are currently enacted in 48 states. Here are some common features of state programs that deal with scrap tires: source of funding for the program, licensing or registration of scrap tire haulers, processors, and end users, manifests for scrap tire shipments, limitations on who may handle scrap tires, financial assurance requirements for scrap tire handlers, and market development activities.[18] Some state programs are now supported by fees charged to the consumer at purchase or disposal of each tire. These fees sometimes called “tipping fees” help to support recycling costs. When the disposal rates charged to consumers are set high this in turn discourages landfill disposal, a simple solution encouraging more affordable tire recycling programs.
See also
Vulcanization/Devulcanization
Pyrolysis
Recycle
Tire
Rubber
Tire fire
Landfill
Landfill liner
Waste Management
Artificial reef
Re-tread
Katy Trail (Dallas)
Rubber mulch
Mousepad
Underlay
Railroad tie
Rubberized asphalt
External links
Manufacturers Association (RMA)
Environmental Protection Agency (EPA)
Ohio Department of Natural Resources
Tire Derived Product Suppliers, California
International Institute of Synthetic Rubber Producers, Inc.
New Scientist article on a microwave process that turns tires back to oil.
Paper recycling
Paper recycling
Paper recycling is the process of recovering waste paper and remaking it into new paper products. There are three categories of paper that can be used as feedstocks for making recycled paper: mill broke, pre-consumer waste, and post-consumer waste.[1] Mill broke is paper trimmings and other paper scrap from the manufacture of paper, and is recycled internally in a paper mill. Pre-consumer waste is material that was discarded before it was ready for consumer use. Post-consumer waste is material that was discarded after actually being used by a consumer. The grades of post-consumer recycled paper are OCC (old corrugated containers), WCC (waxed corrugated containers), ONP (old newspapers), OMG (old magazines), OTD (old telephone directories), and RMP (residential mixed paper).[2] Paper suitable for recycling is called "scrap paper".
Process
While there are differences depending on the specific type of paper being recycled (corrugated fiberboard, newspaper, mixed office waste), recycling processes include the following steps:
Standards
Since the early 1980's, recycled paper has gone from gray and dingy flecked sheets reported to clog up copy machines to an indistinguihable competitor of traditional bright white paper. [3]
However, paper fibers cannot be recycled indefinitely because fiber length and strength are degraded with each use. Individual fibers can only be recycled 4-6 times.[4] When fibers become too short, they are not retained in the pulp or paper and end up in the sludge for disposal. New fibers are usually added to recycled pulp when new paper products are made.
Consequently, most recycled paper will still contain some new pulp.
There is no universal standard for the maximum percentage of virgin pulp in recycled paper.[1][5] 'Recycled' paper is available that includes anywhere from 10 to 100 percent "post-consumer" paper.[6] The EPA mandated the use of 50% post-consumer recycled paper by the federal government, state governments that receive federal funding, and many companies that receive money from the federal government.[7] The EPA does not regulate recycled paper used outside of the government; it only sets a minimum guideline.[1] The UK also does not have any legal standards, only non-mandatory guidelines instituted by a variety of different organizations.[1]
Rationale for recycling
Industrialized paper making takes a tremendous toll on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).[8] Recycling paper reduces this impact.
Forest preservation
Today, 90% of paper pulp is made of wood. Paper production accounts for about 43% of harvested wood,[9] and represents 1.2% of the world's total economic output.[10] Recycling of newsprint saves about 1 tonne of wood while recycling 1 tonne (1.1 ton) of printing or copier paper saves slightly more than 2 tonnes of wood. This is because kraft pulping requires twice as much wood since it removes lignin to produce higher quality fibers than mechanical pulping processes. Relating tonnes of paper recycled to the number of trees not cut is meaningless, since tree size varies tremendously and is the major factor in how much paper can be made from how many trees.[11] Trees raised specifically for pulp production account for 16% of world pulp production, old growth forests 9% and second- and third- and more generation forests account for the balance.[9] Most pulp mill operators practice reforestation to ensure a continuing supply of trees. The Forest Stewardship Council (FSC) certifies paper made from trees harvested according to guidelines meant to ensure good forestry practices.[12] It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (80,000 km²) of forestland.[13]
Energy
There is some debate concerning the energy savings realized in recycling paper. The EIA claims a 40% reduction in energy when paper is recycled versus paper made with unrecycled pulp. [14] while the Bureau of International Recycling, BIR, claims a 64% reduction.[15] Some calculations show that recycling one ton of newspaper saves about 4,000 KWh of electricity, although this may be too high (see comments below on unrecycled pulp). This is enough electricity to power a 3-bedroom European house for an entire year, or enough energy to heat and air-condition the average North American home for almost six months.[16] It must be noted that recycling paper to make pulp may actually consume more fossil fuels than making new pulp via the kraft process since these mills generate all of energy from burning waste wood (bark, roots) and byproduct lignin.[17] Pulp mills producing new mechanical pulp use large amounts of energy, a very rough estimate of the electrical energy needed is 10,000 megajoules (MJ) per tonne of pulp (2500 kW·h per short ton),[18] usually from hydroelectric generating plants. Recycling mills purchase most of their energy from local power companies and since recycling mills tend to be in more urban areas, it is likely that the electricity is generated by burning fossil fuels.
Landfill use
About 35% of municipal solid waste by weight is paper and paper products.[19] Recycling 1 tonne of newspaper eliminates 3 cubic meters of landfill.[20] Incineration of waste paper is usually preferable to landfilling since useful energy is generated. Organic materials, including paper, decompose in landfills, albeit sometimes slowly, releasing methane, a potent greenhouse gas. Many larger landfills now collect this methane for use as a biogas fuel. In highly urbanized areas, such as the northeastern US and most of Europe, land suitable for landfills is scarce and must be used carefully. Fortunately, it is in such areas that collection of waste paper is also most efficient.
Water and air pollution
The US EPA has found that recycling causes 35% less water pollution and 74% less air pollution.[21] Pulp mills can be sources of both air and water pollution, especially if they are producing bleached pulp. Modern mills produce considerably less pollution than those of a few decades ago.
Recycling paper decreases the demand for virgin pulp and thus reduces the overall amount of air and water pollution associated with paper manufacture. Recycled pulp can be bleached with the same chemicals used to bleach virgin pulp, but hydrogen peroxide and sodium hydrosulfite are the most common bleaching agents. Recycled pulp, or paper made from it, is known as PCF (process chlorine free) if no chlorine-containing compounds were used in the recycling process.[22] However it should be noted that recycling mills may have polluting by-products, such as sludge. De-inking at Cross Pointe's Miami, Ohio mill results in sludge weighing 22% of the weight of wastepaper recycled.[23]
Cleaning contaminants from scrap paper
Scrap from paper mills (broke) is the cleanest source for recycling. The high rates of of recycling for post-consumer office paper, newspaper, paperboard, and corrugated fiberboard reflect the efficiency of recycling mills to clean and process the incoming materials. Several technologies are available to sort, screen, filter, and chemically treat the recycled paper.
Many extraneous materials are readily removed. Twine, strapping, etc are removed from the hydropulper by a "ragger". Metal straps and staples can be screened out or removed by a magnet. Film-backed pressure sensitive tape stays intact: the PSA adhesive and the backing are both removed together.[24]
Materials which are more difficult to remove include wax coatings on corrugated cartons and "stickies", soft rubbery particles which can clog the paper maker and contaminate the recycled paper. Stickies can originate from book bindings, hot melt adhesives, PSA adhesives from paper labels, laminating adhesives of reinforced gummed tapes, etc.[25][26][27]
Criticism
Many of the claimed benefits of paper recycling have fallen under criticism; criticized areas include the claim that recycling saves trees, reduces energy consumption, reduces pollution, creates desirable jobs, and saves money.
Recycling facts and figures
In the mid-19th century, there was an increased demand for books and writing material. Up to this time, paper manufacturers had used discarded linen rags for paper, but supply could not keep up with the increased demand. Books were bought at auctions for the purpose of recycling fiber content into new paper, at least in the United Kingdom, by the beginning of the 19th century.[28]
Internationally, about half of all recovered paper comes from converting losses ("pre-consumer" recycling), such as shavings and unsold periodicals; approximately one third comes from household or "post-consumer" waste.[29]
Some statistics on paper consumption:
United States of America
Recycling has long been practiced in the United States. The history of paper recycling has several dates of importance:
1690: The first paper mill to use recycled linen was established by the Rittenhouse family.[31]
1897: The first major recycling center was started by the Benedetto family in New York City, where they collected rags, newspaper, and trash with a pushcart.
1993: The first year when more paper was recycled than was buried in landfills.[32]
Today, over half of the material used to make paper is recovered waste.[33] Paper products are the largest component of municipal solid waste, making up more than 40% of the composition of landfills.[34][35] In 2006, a record 53.4% of the paper consumed in the U.S. (or 53.5 million tons) was recovered for recycling.[36] This is up from a 1990 recovery rate of 33.5%[37]. The U.S. paper industry has set a goal to recover 55 percent of all the paper consumed in the U.S. by 2012. Paper packaging recovery, specific to paper products used by the packaging industry, was responsible for about 76.6% of packaging materials recycled with more than 24 million pounds recovered in 2005.[38]
Twenty years ago, only one curbside recycling program existed in the United States, which collected several materials at the curb. By 1998, 9,000 curbside programs and 12,000 recyclable drop-off centers had sprouted up across the nation. As of 1999, 480 materials recovery facilities had been established to process the collected materials.[39]
External links
Joearth - Information for responsible paper purchasing
Paper recycling
Conservatree - Information on environmental and recycled paper
Information on recycling and paper drives for fundraising
Paper Industry Association Council: paperrecycles.org
U.S. Environmental Protection Agency: Paper and Paperboard Products
Paper recycling is the process of recovering waste paper and remaking it into new paper products. There are three categories of paper that can be used as feedstocks for making recycled paper: mill broke, pre-consumer waste, and post-consumer waste.[1] Mill broke is paper trimmings and other paper scrap from the manufacture of paper, and is recycled internally in a paper mill. Pre-consumer waste is material that was discarded before it was ready for consumer use. Post-consumer waste is material that was discarded after actually being used by a consumer. The grades of post-consumer recycled paper are OCC (old corrugated containers), WCC (waxed corrugated containers), ONP (old newspapers), OMG (old magazines), OTD (old telephone directories), and RMP (residential mixed paper).[2] Paper suitable for recycling is called "scrap paper".
Process
While there are differences depending on the specific type of paper being recycled (corrugated fiberboard, newspaper, mixed office waste), recycling processes include the following steps:
- Pulping: Adding water and applying mechanical action to separate fibers from each other.
- Screening: Using screens, with either slots or holes, to remove contaminants that are larger than pulp fibers.
- Centrifugal cleaning: Spinning the pulp slurry in a cleaner causes materials that are more dense than pulp fibers to move outward and be rejected.
- Flotation: Passing air bubbles through the pulp slurry, with a surfactant present, causes ink particles to collect with the foam on the surface. By removing contaminated foam, pulp is made brighter. This step is sometimes called deinking.
- Kneading or dispersion: Mechanical action is applied to fragment contaminant particles.
- Washing: Small particles are removed by passing water through the pulp.
- Bleaching: If white paper is desired, bleaching uses peroxides or hydrosulfites to remove color from the pulp.
- Papermaking: The clean (and/or bleached) fiber is made into a "new" paper product in the same way that virgin paper is made.
- Dissolved air flotation: Process water is cleaned for reuse.
Waste disposal: The unusable material left over, mainly ink, plastics, filler and short fibers, is called sludge. The sludge is buried in a landfill, burned to create energy at the paper mill or used as a fertilizer by local farmers.
Standards
Since the early 1980's, recycled paper has gone from gray and dingy flecked sheets reported to clog up copy machines to an indistinguihable competitor of traditional bright white paper. [3]
However, paper fibers cannot be recycled indefinitely because fiber length and strength are degraded with each use. Individual fibers can only be recycled 4-6 times.[4] When fibers become too short, they are not retained in the pulp or paper and end up in the sludge for disposal. New fibers are usually added to recycled pulp when new paper products are made.
Consequently, most recycled paper will still contain some new pulp.
There is no universal standard for the maximum percentage of virgin pulp in recycled paper.[1][5] 'Recycled' paper is available that includes anywhere from 10 to 100 percent "post-consumer" paper.[6] The EPA mandated the use of 50% post-consumer recycled paper by the federal government, state governments that receive federal funding, and many companies that receive money from the federal government.[7] The EPA does not regulate recycled paper used outside of the government; it only sets a minimum guideline.[1] The UK also does not have any legal standards, only non-mandatory guidelines instituted by a variety of different organizations.[1]
Rationale for recycling
Industrialized paper making takes a tremendous toll on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).[8] Recycling paper reduces this impact.
Forest preservation
Today, 90% of paper pulp is made of wood. Paper production accounts for about 43% of harvested wood,[9] and represents 1.2% of the world's total economic output.[10] Recycling of newsprint saves about 1 tonne of wood while recycling 1 tonne (1.1 ton) of printing or copier paper saves slightly more than 2 tonnes of wood. This is because kraft pulping requires twice as much wood since it removes lignin to produce higher quality fibers than mechanical pulping processes. Relating tonnes of paper recycled to the number of trees not cut is meaningless, since tree size varies tremendously and is the major factor in how much paper can be made from how many trees.[11] Trees raised specifically for pulp production account for 16% of world pulp production, old growth forests 9% and second- and third- and more generation forests account for the balance.[9] Most pulp mill operators practice reforestation to ensure a continuing supply of trees. The Forest Stewardship Council (FSC) certifies paper made from trees harvested according to guidelines meant to ensure good forestry practices.[12] It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (80,000 km²) of forestland.[13]
Energy
There is some debate concerning the energy savings realized in recycling paper. The EIA claims a 40% reduction in energy when paper is recycled versus paper made with unrecycled pulp. [14] while the Bureau of International Recycling, BIR, claims a 64% reduction.[15] Some calculations show that recycling one ton of newspaper saves about 4,000 KWh of electricity, although this may be too high (see comments below on unrecycled pulp). This is enough electricity to power a 3-bedroom European house for an entire year, or enough energy to heat and air-condition the average North American home for almost six months.[16] It must be noted that recycling paper to make pulp may actually consume more fossil fuels than making new pulp via the kraft process since these mills generate all of energy from burning waste wood (bark, roots) and byproduct lignin.[17] Pulp mills producing new mechanical pulp use large amounts of energy, a very rough estimate of the electrical energy needed is 10,000 megajoules (MJ) per tonne of pulp (2500 kW·h per short ton),[18] usually from hydroelectric generating plants. Recycling mills purchase most of their energy from local power companies and since recycling mills tend to be in more urban areas, it is likely that the electricity is generated by burning fossil fuels.
Landfill use
About 35% of municipal solid waste by weight is paper and paper products.[19] Recycling 1 tonne of newspaper eliminates 3 cubic meters of landfill.[20] Incineration of waste paper is usually preferable to landfilling since useful energy is generated. Organic materials, including paper, decompose in landfills, albeit sometimes slowly, releasing methane, a potent greenhouse gas. Many larger landfills now collect this methane for use as a biogas fuel. In highly urbanized areas, such as the northeastern US and most of Europe, land suitable for landfills is scarce and must be used carefully. Fortunately, it is in such areas that collection of waste paper is also most efficient.
Water and air pollution
The US EPA has found that recycling causes 35% less water pollution and 74% less air pollution.[21] Pulp mills can be sources of both air and water pollution, especially if they are producing bleached pulp. Modern mills produce considerably less pollution than those of a few decades ago.
Recycling paper decreases the demand for virgin pulp and thus reduces the overall amount of air and water pollution associated with paper manufacture. Recycled pulp can be bleached with the same chemicals used to bleach virgin pulp, but hydrogen peroxide and sodium hydrosulfite are the most common bleaching agents. Recycled pulp, or paper made from it, is known as PCF (process chlorine free) if no chlorine-containing compounds were used in the recycling process.[22] However it should be noted that recycling mills may have polluting by-products, such as sludge. De-inking at Cross Pointe's Miami, Ohio mill results in sludge weighing 22% of the weight of wastepaper recycled.[23]
Cleaning contaminants from scrap paper
Scrap from paper mills (broke) is the cleanest source for recycling. The high rates of of recycling for post-consumer office paper, newspaper, paperboard, and corrugated fiberboard reflect the efficiency of recycling mills to clean and process the incoming materials. Several technologies are available to sort, screen, filter, and chemically treat the recycled paper.
Many extraneous materials are readily removed. Twine, strapping, etc are removed from the hydropulper by a "ragger". Metal straps and staples can be screened out or removed by a magnet. Film-backed pressure sensitive tape stays intact: the PSA adhesive and the backing are both removed together.[24]
Materials which are more difficult to remove include wax coatings on corrugated cartons and "stickies", soft rubbery particles which can clog the paper maker and contaminate the recycled paper. Stickies can originate from book bindings, hot melt adhesives, PSA adhesives from paper labels, laminating adhesives of reinforced gummed tapes, etc.[25][26][27]
Criticism
Many of the claimed benefits of paper recycling have fallen under criticism; criticized areas include the claim that recycling saves trees, reduces energy consumption, reduces pollution, creates desirable jobs, and saves money.
Recycling facts and figures
In the mid-19th century, there was an increased demand for books and writing material. Up to this time, paper manufacturers had used discarded linen rags for paper, but supply could not keep up with the increased demand. Books were bought at auctions for the purpose of recycling fiber content into new paper, at least in the United Kingdom, by the beginning of the 19th century.[28]
Internationally, about half of all recovered paper comes from converting losses ("pre-consumer" recycling), such as shavings and unsold periodicals; approximately one third comes from household or "post-consumer" waste.[29]
Some statistics on paper consumption:
- The average per capita paper use in the USA in 2001 was 700 pounds (318 kg). The average per capita paper use worldwide was 110 pounds (50 kg).[30]
- It is estimated that 95% of business information is still stored on paper. [Source: International Institute for Environment and Development (IIED) Discussion Paper (IIED, London, September 1996)]
- Although paper is traditionally identified with reading and writing, communications has now been replaced by packaging as the single largest category of paper use at 41% of all paper used. [Source: North American Factbook PPI, 1995. (Figures are for 1993)]
- 115 billion sheets of paper are used annually for personal computers [Source: Worldwatch Institute]. The average daily web user prints 28 pages daily [Source: Gartner group and HP]
- Most corrugated fiberboard boxes have over 25% recycled fibers. Some are 100% recycled fiber.
United States of America
Recycling has long been practiced in the United States. The history of paper recycling has several dates of importance:
1690: The first paper mill to use recycled linen was established by the Rittenhouse family.[31]
1897: The first major recycling center was started by the Benedetto family in New York City, where they collected rags, newspaper, and trash with a pushcart.
1993: The first year when more paper was recycled than was buried in landfills.[32]
Today, over half of the material used to make paper is recovered waste.[33] Paper products are the largest component of municipal solid waste, making up more than 40% of the composition of landfills.[34][35] In 2006, a record 53.4% of the paper consumed in the U.S. (or 53.5 million tons) was recovered for recycling.[36] This is up from a 1990 recovery rate of 33.5%[37]. The U.S. paper industry has set a goal to recover 55 percent of all the paper consumed in the U.S. by 2012. Paper packaging recovery, specific to paper products used by the packaging industry, was responsible for about 76.6% of packaging materials recycled with more than 24 million pounds recovered in 2005.[38]
Twenty years ago, only one curbside recycling program existed in the United States, which collected several materials at the curb. By 1998, 9,000 curbside programs and 12,000 recyclable drop-off centers had sprouted up across the nation. As of 1999, 480 materials recovery facilities had been established to process the collected materials.[39]
External links
Joearth - Information for responsible paper purchasing
Paper recycling
Conservatree - Information on environmental and recycled paper
Information on recycling and paper drives for fundraising
Paper Industry Association Council: paperrecycles.org
U.S. Environmental Protection Agency: Paper and Paperboard Products
Recycling bin
Recycling bin
A recycling bin (or recycle bin) is a container used to hold recyclables before they are taken to recycling centers. Recycling bins exist in various sizes for use in homes, offices, and large public facilities. Separate containers are often provided for paper, tin or aluminum cans, and glass or plastic bottles.
Many recycling bins are designed to be easily recognisable, and are marked with slogans promoting recycling on a blue or green background. Others are intentionally unobtrusive. Bins are sometimes different colors so that recyclers may differentiate between the types of materials to be placed in them. Blue bins usually indicate metals and plastics and green indicate papers.
Recycling bins are a common element of municipal curbside collection programs, which frequently distribute the bins to encourage participation.
See also
Recycling
A recycling bin (or recycle bin) is a container used to hold recyclables before they are taken to recycling centers. Recycling bins exist in various sizes for use in homes, offices, and large public facilities. Separate containers are often provided for paper, tin or aluminum cans, and glass or plastic bottles.
Many recycling bins are designed to be easily recognisable, and are marked with slogans promoting recycling on a blue or green background. Others are intentionally unobtrusive. Bins are sometimes different colors so that recyclers may differentiate between the types of materials to be placed in them. Blue bins usually indicate metals and plastics and green indicate papers.
Recycling bins are a common element of municipal curbside collection programs, which frequently distribute the bins to encourage participation.
See also
Recycling
Recycling
Recycling
Recycling is the reprocessing of materials into new products. Recycling generally prevents the waste of potentially useful materials, reduces the consumption of raw materials and reduces energy usage, and hence greenhouse gas emissions, compared to virgin production.[1] Recycling is a key concept of modern waste management and is the third component of the waste hierarchy.
Recyclable materials, also called "recyclables", may originate from a wide range of sources including the home and industry. They include glass, paper, aluminium, asphalt, iron, textiles and plastics. Biodegradable waste, such as food waste or garden waste, is also recyclable with the assistance of micro-organisms through composting or anaerobic digestion.
Recyclates are sorted and separated into material types. Contamination of the recylates with other materials must be prevented to increase the recyclates' value and facilitate easier reprocessing for the ultimate recycling facility. This sorting can be performed either by the producer of the waste or within semi- or fully-automated materials recovery facilities.
There are two common household methods of recycling. In curbside collection, consumers leave presorted recyclable materials in front of their property to be collected by a recycling vehicle.
With a "bring" or carry-in system, the householder takes the materials to collection points, such as transfer stations or civic amenity sites.
The term recycling does not generally include reuse, in which existing items are used for a new purpose.
History
Recycling has been a common practice throughout human history. In pre-industrial times, scrap made of bronze and other precious metals was collected in Europe and melted down for perpetual reuse, and in Britain dust and ash from wood and coal fires was downcycled as a base material in brick making. The main driver for these types of recycling was the economic advantage of obtaining recycled feedstock instead of acquiring virgin material, as well as a lack of public waste removal in ever more-populated sites.
Paper recycling began in Britain in 1921, when the British Waste Paper Association (now Confederation of Paper Industries) was established to encourage trade in waste paper recycling.
Resource shortages caused by the world wars, and other such world-changing occurrences greatly encouraged recycling. Massive government promotion campaigns were carried out in World War II in every country involved in the war, urging citizens to donate metals and conserve fiber, as a matter of significant patriotic importance. Resource conservation programs established during the war were continued in some countries without an abundance of natural resources, such as Japan, after the war ended.
The next big investment in recycling occurred in the 1970s, due to rising energy costs. Recycling aluminum uses only 5% of the energy required by virgin production; glass, paper and metals have less dramatic but very significant energy savings when recycled feedstock is used [2]. The passage of the Clean Water Act of 1977 in the USA created strong demand for bleached paper (office paper whose fibre has already been bleached white increased in value as water effluent became more expensive).
In 1973, the city of Berkeley, California began one of the first curbside collection programs with monthly pick ups of newspapers from residences. Since then several countries have started and expanded various doorstep collection schemes. Around this time, Woodbury, New Jersey was also a forerunner of the recycling industry in the United States, being the first in the state to mandate it.
In 1987, the Mobro 4000 barge hauled garbage from New York to North Carolina, where it had been denied. It was then sent to Belize, where it was denied as well. Finally, the barge returned to New York and the garbage was incinerated. The incident led to heated discussions in the media about waste disposal and recycling. The incident is often referred to as igniting the recycling hysteria of the 1990s.
One event that initiated recycling efforts occurred in 1989 when Berkeley banned the use of polystyrene packaging for keeping McDonald's hamburgers warm. One effect of this ban was to raise the ire of management at the Dow Chemical Company, the world's largest manufacturer of polystyrene, which led to the first major effort to show that plastics can be recycled. By 1999, there were 1,677 companies in the USA alone involved in the post-consumer plastics recycling business.
In Germany the introduction of a Packaging Ordinance under the Waste Act led to the introduction of the Green Dot program. Originally launched by Duales System Deutschland GmbH (DSD) in 1990, the scheme has since been rolled out to 23 other European countries. The Green Dot scheme is captured under the European "Packaging and Packaging Waste Directive - 94/62/EC" and is binding for all companies if their products use packaging.
Benefits
Recycling is beneficial in two ways: it reduces the inputs (energy and raw materials) to a production system and reduces the amount of waste produced for disposal.
A study conducted by the Technical University of Denmark found that in 80% of cases, recycling is the most efficient method to dispose of household waste.[2]
Some materials like aluminum can be recycled indefinitely as there is no change to the materials. Other recycled materials like paper require a percentage of raw materials (wood fibers) to be added to compensate for the degradation of existing fibers. Recycling aluminium saves 95% of the energy cost of processing new aluminium[2] because the melting temperature is reduced from 900 °C to 600 °C. It is by far the most efficient material to recycle. Recycling plastic saves 70% of the energy used in creating new plastic, and paper recycling saves 40% of the energy required to make a new product.[2]
The resources being processed are purer, thus less energy is needed to process them.
Additionally less energy is needed to transport them from the place of extraction (e.g. bauxite/aluminium ore mines in Brazil or coniferous forests in Scandinavia as compared to domestic areas).
This reduces the environmental, social, and usually the economic costs of manufacturing.
For example, bauxite mines in Brazil displace indigenous people, create noise pollution from blasting, machinery and transport, and create air pollution in the form of particulates (dust). The habitat loss and visual destruction is also negative both to the aesthetic qualities of the areas and the local environment.
The most commonly used methods for waste disposal (landfill, pyrolysis, incineration) may be environmentally damaging and unsustainable. Therefore any way to reduce the volume of waste being disposed in this fashion may be beneficial. The maximum environmental benefit is gained by waste minimization (reducing the amount of waste produced), and reusing items in their current form such as refilling bottles.
In the past recycling has been a fragmented industry with recycling companies only accepting specific materials for recycling, or only common materials such as plastic or metals. More recent approaches have resulted in recycling companies that accept a wide variety of materials or emerging market materials such as ceiling tiles, carpet, stained wood etc.. An example of a company that accepts a wide variety of materials, including emerging recycling markets is the Green Recycling Network.
Drawbacks and criticism
All recycling techniques consume energy for transportation and processing and some also use considerable amounts of water, although recycling processes seldom amount to the level of resource use associated with raw materials processing.[3]
There may also be drawbacks with the collection methods associated with recycling. Increasing collections of separated wastes adds to vehicle movements and the production of carbon dioxide.
This may be negated however by centralized facilities such as some advanced material recovery facilities and mechanical biological treatment systems for the separation of mixed wastes. It has been calculated that collecting waste and disposing it in a landfill is about $60 a ton opposed to separate collecting and taking it to be recycled costs $150 a ton.[4]
Recycled materials also sometimes cost more financially than their non-recycled versions. This is not universal to every recycled product, but it does occur.[5]
Negative consequences from mercury recycling have been cited by The Wall Street Journal.[6]
The article traces mercury recovered from American recycling programs into sales of mercury for alluvial mining activities in Brazil. During the autumn of 2006, the European Union banned the export of liquid mercury, and a life-cycle analysis prior to institution of recycling programs may reduce the risk of unintended environmental consequences.
For some materials, recycling is more expensive than landfill disposal unless externalities are considered.[citation needed] For these products, there is an opportunity cost to recycling. Some argue that the financial costs of recycling some materials outweigh the environmental benefits.
Some skeptics also argue that the environmental benefits of recycling do not compensate for the extra effort it may require.[7]
John Tierney, in an article in The New York Times claimed that government mandated recycling wastes more resources than it saves.[8] Some highlights from the article:
Recycling techniques
Many different materials can be recycled but each type requires a different technique.
Aggregates & concrete
Concrete aggregate collected from demolition sites is put through a crushing machine, often along with asphalt, bricks, dirt, and rocks. Smaller pieces of concrete are used as gravel for new construction projects. Crushed recycled concrete can also be used as the dry aggregate for brand new concrete if it is free of contaminants. This reduces the need for other rocks to be dug up, which in turn saves trees and habitats.
Batteries
The large variation in size and type of batteries makes their recycling extremely difficult: they must first be sorted into similar kinds and each kind requires an individual recycling process.
Additionally, older batteries contain mercury and cadmium, harmful materials which must be handled with care.
Lead-acid batteries, like those used in automobiles, are relatively easy to recycle and many new lead-acid batteries contain a high percentage of recycled material.
Biodegradable waste
Biodegradable waste can be recycled into useful material by biological decomposition. There are two mechanisms by which this can occur. The most common mechanism of recycling of household organic waste is home composting or municipal curbside collection of green wastes sent to large scale composting plants.
Alternatively organic waste can be converted into biogas and soil improver using anaerobic digestion. Here organic wastes are broken down by anaerobic microorganisms in biogas plants.
The biogas can be converted into renewable electricity or burnt for environmentally friendly heating. Advanced technologies such as mechanical biological treatment are able to sort the recyclable elements of the waste out before biological treatment by either composting, anaerobic digestion or biodrying.
Sulabh International, an Indian NGO designed a cheap toilet system that recycles human waste into biogas and fertilizer.
Electronics disassembly and reclamation
The direct disposal of electrical equipment — such as old computers and mobile phones — is banned in many areas due to the toxic contents of certain components. The recycling process works by mechanically separating the metals, plastics and circuit boards contained in the appliance. When this is done on a large scale at an electronic waste recycling plant, component recovery can be achieved in a cost-effective manner.
Electronic devices, including audio-visual components (televisions, VCRs, stereo equipment), mobile phones and other hand-held devices, and computer components, contain valuable elements and substances suitable for reclamation, including lead, copper, and gold. They also contain a plethora of toxic substances, such as dioxins, Polychlorinated biphenylsPCBs, cadmium, chromium, radioactive isotopes, and mercury. Additionally, the processing required to reclaim the precious substances (including incineration and acid treatments) release, generate and synthesize further toxic by-products.
In the United States, an estimated 70% of heavy metals in landfills come from discarded electronics.[9]Some regional governments are attempting to curtail the accumulation of electronics in landfills by passing laws obligating manufacturers and consumers to recycle these devices,[10] but because in many cases safe dismantlement of these devices in accordance with first world safety standards is unprofitable,[citation needed] historically much of the electronic waste has been shipped to countries with lower or less rigorously-enforced safety protocols.
Places like Guiyu, China dismantle tons of electronics every year, profiting from the sale of precious metals, but at the cost of the local environment and the health of its residents.[11][12]
Mining to produce the same metals, to meet demand for finished products in the west, also occurs in the same countries, and the United Nations Conference on Trade and Development (UNCTAD) has recommended that restrictions against recycling exports be balanced against the environmental costs of recovering those materials from mining. Hard rock mining in the USA produces 45% of all toxics produced by all USA industries (2001 US EPA Toxics Release Inventory).
Printer ink cartridges & toners
Printer ink cartridges can be recycled. They are sorted into different brands and models which are then resold back to the companies that created these cartridges. The companies then refill the ink reservoir which can be sold back to consumers. Toner cartridges are recycled the same way as ink cartridges, using toner instead of ink. This method of recycling is highly efficient as there is no energy spent on melting and recreating the recycled object itself.
Ferrous metals
Iron and steel are the world's most recycled materials, and among the easiest materials to recycle, as they can be separated magnetically from the waste stream. Recycling is via a steelworks: scrap is either remelted in an Electric Arc Furnace (90-100% scrap), or used as part of the charge in a Basic Oxygen Furnace (around 25% scrap).[13] Any grade of steel can be recycled to top quality new metal, with no 'downgrading' from prime to lower quality materials as steel is recycled repeatedly. 42% of crude steel produced is recycled material.[14]
Non-ferrous metals
Aluminium is shredded and ground into small pieces or crushed into bales. These pieces or bales are melted in an aluminium smelter to produce molten aluminium. By this stage the recycled aluminium is indistinguishable from virgin aluminium and further processing is identical for both.
Due to the high melting point of aluminium ore, large amounts of energy are required to extract aluminium from ore, making the environmental benefits of recycling aluminium enormous.
Recycling aluminium only results in approximately 5% of the CO2 that would be released during the production of raw aluminium.[15] The percentage is even smaller when considering the complete cycle of mining and transporting the aluminium. Also, as open-cut mining is most often used for obtaining aluminium ore, mining destroys large sections of natural land.
An aluminium can is 100% recyclable. Every time a can is recycled, enough energy is saved to power a television for about three hours (compared to mining and producing a new can).[16]
Glass
Glass bottles and jars are gathered via curbside collection schemes and bottle banks, where the glass may be sorted into color categories. The collected glass cullet is taken to a glass recycling plant where it is monitored for purity and contaminants are removed. The cullet is crushed and added to a raw material mix in a melting furnace. It is then mechanically blown or molded into new jars or bottles. Glass cullet is also used in the construction industry for aggregate and glassphalt. Glassphalt is a road-laying material which comprises around 30% recycled glass.
Glass can be recycled indefinitely as its structure does not deteriorate when reprocessed.
Paper
Recycled paper is made from waste paper, usually mixed with fresh wood pulp. If the paper contains ink, it must be deinked. This also removes fillers, clays, and fiber fragments.
Almost all paper can be recycled today, but some types are harder to recycle than others.
Papers coated with plastic or aluminum foil, and papers that are waxed, pasted, or gummed are usually not recycled because the process is too expensive. Gift wrap paper also cannot be recycled. Different types of paper are usually sorted before recycling, such as newspapers and cardboard boxes.
Different grades of paper are recycled into different types of new products. Old newspapers are usually made into new newsprint, egg cartons, or paperboard. Old corrugated boxes are made into new corrugated boxes or paperboard. High-grade white office paper can be made into almost any new paper product: stationery, newsprint, magazines, or books.
Sometimes recyclers ask for the removal of the glossy inserts from newspapers because they are a different type of paper. Glossy inserts have a heavy clay coating that some paper mills cannot accept. Most of the clay is removed from the recycled pulp as sludge which must be disposed. If the coated paper is 20% by weight clay, then each ton of glossy paper produces more than 200 kg of sludge and less than 800 kg of fiber. Uncoated (no clay), recycled newsprint gives less sludge and more useable fiber.
Paper can only be recycled a finite number of times due to the shortening of paper fibers making the material less versatile. Often it will be mixed with a quantity of virgin material, referred to as downcycling. This does not however exclude the material from being used in other processes such as composting or anaerobic digestion, where further value can be extracted from the material in the form of compost or biogas.
Plastic
Plastic recycling is the process of recovering scrap or waste plastics and reprocessing the material into useful products. Compared to glass or metallic materials, plastic poses unique challenges - because of the massive number of types of plastic, they each carry a resin identification code, and must be sorted before they can be recycled. This can be costly - while metals can be sorted using electromagnets, no such 'easy sorting' capability exists for plastics. In addition to this, while labels do not need to be removed from bottles for recycling, lids are often made from a different kind of non-recyclable plastic.
Plastics recycling rates lag far behind those of other items, such as newspaper and aluminium; consumers are typically unsure of how to recycle plastics, and compared to paper and metals fewer recycling facilities exist.
Textiles
When considering textile recycling one must understand what the material consists of. Most textiles are composites of cotton (biodegradable material) and synthetic plastics. The textile's composition will affect its durability and method of recycling.
Workers sort and separate collected textiles into good quality clothing and shoes which can be reused or worn. There is a trend of moving these facilities from developed countries to developing countries.[17]
Damaged textiles are further sorted into grades to make industrial wiping cloths and for use in paper manufacture or material suitable for fibre reclamation and filling products. If textile reprocessors receive wet or soiled clothes however, these may still be disposed of in a landfill, as the washing and drying facilities are not present at sorting units. [18]
Fibre reclamation mills sort textiles according to fibre type and colour. Colour sorting eliminates the need to re-dye the recycled textiles. The textiles are shredded into "shoddy" fibres and blended with other selected fibres, depending on the intended end use of the recycled yarn. The blended mixture is carded to clean and mix the fibres and spun ready for weaving or knitting.
The fibres can also be compressed for mattress production. Textiles sent to the flocking industry are shredded to make filling material for car insulation, roofing felts, loudspeaker cones, panel linings and furniture padding.
Timber
Recycling timber has become popular due to its image as an environmentally friendly product, with consumers commonly believing that by purchasing recycled wood the demand for green timber will fall and ultimately benefit the environment. Greenpeace also view recycled timber as an environmentally friendly product, citing it as the most preferable timber source on their website. The arrival of recycled timber as a construction product has been important in both raising industry and consumer awareness towards deforestation and promoting timber mills to adopt more environmentally friendly practices.
Other Techniques
Several other materials are also commonly recycled, frequently at an industrial level.
Ship breaking is one example that has associated environmental, health, and safety risks for the area where the operation takes place; balancing all these considerations is an environmental justice problem.
Tires are also commonly recycled. Used tires can be added to asphalt, producing road surfaces that are more durable, create less traffic noise, and absorb precipitation better than traditional asphalt[citation needed]. Tires can also be used to make rubber mulch, which is used on playgrounds for safety.
Metal scavenged from automobiles can also be recycled at an industrial scale.
International Universal Recycling Codes
The communication and identification are laid out in International Universal Recycling Codes.
These codes outline what material an item is made from, to facilitate easier reprocessing.
See also
Anaerobic digestion
Composting
Downcycling
Recyclable waste
Materials Recovery Facility
Regiving
Pollution Prevention
Cheapcycle
Re-use
Types of recycling
Full Depth Recycling
Ship-Submarine recycling program
Thermal depolymerization
Chemical reclamation, for example hydrochloric acid regeneration
General topics
Environmentalism
Energy conservation
Waste management
Extended producer responsibility
Pay As You Throw
Recycling in the United States
Trade associations
International Solid Waste Association
Solid Waste Association of North America
Chartered Institute of Wastes Management
Recycling is the reprocessing of materials into new products. Recycling generally prevents the waste of potentially useful materials, reduces the consumption of raw materials and reduces energy usage, and hence greenhouse gas emissions, compared to virgin production.[1] Recycling is a key concept of modern waste management and is the third component of the waste hierarchy.
Recyclable materials, also called "recyclables", may originate from a wide range of sources including the home and industry. They include glass, paper, aluminium, asphalt, iron, textiles and plastics. Biodegradable waste, such as food waste or garden waste, is also recyclable with the assistance of micro-organisms through composting or anaerobic digestion.
Recyclates are sorted and separated into material types. Contamination of the recylates with other materials must be prevented to increase the recyclates' value and facilitate easier reprocessing for the ultimate recycling facility. This sorting can be performed either by the producer of the waste or within semi- or fully-automated materials recovery facilities.
There are two common household methods of recycling. In curbside collection, consumers leave presorted recyclable materials in front of their property to be collected by a recycling vehicle.
With a "bring" or carry-in system, the householder takes the materials to collection points, such as transfer stations or civic amenity sites.
The term recycling does not generally include reuse, in which existing items are used for a new purpose.
History
Recycling has been a common practice throughout human history. In pre-industrial times, scrap made of bronze and other precious metals was collected in Europe and melted down for perpetual reuse, and in Britain dust and ash from wood and coal fires was downcycled as a base material in brick making. The main driver for these types of recycling was the economic advantage of obtaining recycled feedstock instead of acquiring virgin material, as well as a lack of public waste removal in ever more-populated sites.
Paper recycling began in Britain in 1921, when the British Waste Paper Association (now Confederation of Paper Industries) was established to encourage trade in waste paper recycling.
Resource shortages caused by the world wars, and other such world-changing occurrences greatly encouraged recycling. Massive government promotion campaigns were carried out in World War II in every country involved in the war, urging citizens to donate metals and conserve fiber, as a matter of significant patriotic importance. Resource conservation programs established during the war were continued in some countries without an abundance of natural resources, such as Japan, after the war ended.
The next big investment in recycling occurred in the 1970s, due to rising energy costs. Recycling aluminum uses only 5% of the energy required by virgin production; glass, paper and metals have less dramatic but very significant energy savings when recycled feedstock is used [2]. The passage of the Clean Water Act of 1977 in the USA created strong demand for bleached paper (office paper whose fibre has already been bleached white increased in value as water effluent became more expensive).
In 1973, the city of Berkeley, California began one of the first curbside collection programs with monthly pick ups of newspapers from residences. Since then several countries have started and expanded various doorstep collection schemes. Around this time, Woodbury, New Jersey was also a forerunner of the recycling industry in the United States, being the first in the state to mandate it.
In 1987, the Mobro 4000 barge hauled garbage from New York to North Carolina, where it had been denied. It was then sent to Belize, where it was denied as well. Finally, the barge returned to New York and the garbage was incinerated. The incident led to heated discussions in the media about waste disposal and recycling. The incident is often referred to as igniting the recycling hysteria of the 1990s.
One event that initiated recycling efforts occurred in 1989 when Berkeley banned the use of polystyrene packaging for keeping McDonald's hamburgers warm. One effect of this ban was to raise the ire of management at the Dow Chemical Company, the world's largest manufacturer of polystyrene, which led to the first major effort to show that plastics can be recycled. By 1999, there were 1,677 companies in the USA alone involved in the post-consumer plastics recycling business.
In Germany the introduction of a Packaging Ordinance under the Waste Act led to the introduction of the Green Dot program. Originally launched by Duales System Deutschland GmbH (DSD) in 1990, the scheme has since been rolled out to 23 other European countries. The Green Dot scheme is captured under the European "Packaging and Packaging Waste Directive - 94/62/EC" and is binding for all companies if their products use packaging.
Benefits
Recycling is beneficial in two ways: it reduces the inputs (energy and raw materials) to a production system and reduces the amount of waste produced for disposal.
A study conducted by the Technical University of Denmark found that in 80% of cases, recycling is the most efficient method to dispose of household waste.[2]
Some materials like aluminum can be recycled indefinitely as there is no change to the materials. Other recycled materials like paper require a percentage of raw materials (wood fibers) to be added to compensate for the degradation of existing fibers. Recycling aluminium saves 95% of the energy cost of processing new aluminium[2] because the melting temperature is reduced from 900 °C to 600 °C. It is by far the most efficient material to recycle. Recycling plastic saves 70% of the energy used in creating new plastic, and paper recycling saves 40% of the energy required to make a new product.[2]
The resources being processed are purer, thus less energy is needed to process them.
Additionally less energy is needed to transport them from the place of extraction (e.g. bauxite/aluminium ore mines in Brazil or coniferous forests in Scandinavia as compared to domestic areas).
This reduces the environmental, social, and usually the economic costs of manufacturing.
For example, bauxite mines in Brazil displace indigenous people, create noise pollution from blasting, machinery and transport, and create air pollution in the form of particulates (dust). The habitat loss and visual destruction is also negative both to the aesthetic qualities of the areas and the local environment.
The most commonly used methods for waste disposal (landfill, pyrolysis, incineration) may be environmentally damaging and unsustainable. Therefore any way to reduce the volume of waste being disposed in this fashion may be beneficial. The maximum environmental benefit is gained by waste minimization (reducing the amount of waste produced), and reusing items in their current form such as refilling bottles.
In the past recycling has been a fragmented industry with recycling companies only accepting specific materials for recycling, or only common materials such as plastic or metals. More recent approaches have resulted in recycling companies that accept a wide variety of materials or emerging market materials such as ceiling tiles, carpet, stained wood etc.. An example of a company that accepts a wide variety of materials, including emerging recycling markets is the Green Recycling Network.
Drawbacks and criticism
All recycling techniques consume energy for transportation and processing and some also use considerable amounts of water, although recycling processes seldom amount to the level of resource use associated with raw materials processing.[3]
There may also be drawbacks with the collection methods associated with recycling. Increasing collections of separated wastes adds to vehicle movements and the production of carbon dioxide.
This may be negated however by centralized facilities such as some advanced material recovery facilities and mechanical biological treatment systems for the separation of mixed wastes. It has been calculated that collecting waste and disposing it in a landfill is about $60 a ton opposed to separate collecting and taking it to be recycled costs $150 a ton.[4]
Recycled materials also sometimes cost more financially than their non-recycled versions. This is not universal to every recycled product, but it does occur.[5]
Negative consequences from mercury recycling have been cited by The Wall Street Journal.[6]
The article traces mercury recovered from American recycling programs into sales of mercury for alluvial mining activities in Brazil. During the autumn of 2006, the European Union banned the export of liquid mercury, and a life-cycle analysis prior to institution of recycling programs may reduce the risk of unintended environmental consequences.
For some materials, recycling is more expensive than landfill disposal unless externalities are considered.[citation needed] For these products, there is an opportunity cost to recycling. Some argue that the financial costs of recycling some materials outweigh the environmental benefits.
Some skeptics also argue that the environmental benefits of recycling do not compensate for the extra effort it may require.[7]
John Tierney, in an article in The New York Times claimed that government mandated recycling wastes more resources than it saves.[8] Some highlights from the article:
- In cases where recycling truly does save resources, such as with large scraps of aluminum, this will be reflected in market prices, and voluntary recycling will take place. Thus, there is no need for the government to mandate it.
- Each year the United States fills up over 9 square miles of landfill space. Once full, much of that land gets turned into parks.
- Tree farmers plant more trees than they cut down.
- Government mandated recycling is more expensive than putting the garbage into landfills, which means that this recycling uses up more resources than it saves.
- Some small towns with landfills are happy to import garbage from other cities and states because it provides jobs and tax revenue.
- Today's modern landfills are much cleaner and safer, and much less likely to leak and pollute than the landfills of the past.
Recycling techniques
Many different materials can be recycled but each type requires a different technique.
Aggregates & concrete
Concrete aggregate collected from demolition sites is put through a crushing machine, often along with asphalt, bricks, dirt, and rocks. Smaller pieces of concrete are used as gravel for new construction projects. Crushed recycled concrete can also be used as the dry aggregate for brand new concrete if it is free of contaminants. This reduces the need for other rocks to be dug up, which in turn saves trees and habitats.
Batteries
The large variation in size and type of batteries makes their recycling extremely difficult: they must first be sorted into similar kinds and each kind requires an individual recycling process.
Additionally, older batteries contain mercury and cadmium, harmful materials which must be handled with care.
Lead-acid batteries, like those used in automobiles, are relatively easy to recycle and many new lead-acid batteries contain a high percentage of recycled material.
Biodegradable waste
Biodegradable waste can be recycled into useful material by biological decomposition. There are two mechanisms by which this can occur. The most common mechanism of recycling of household organic waste is home composting or municipal curbside collection of green wastes sent to large scale composting plants.
Alternatively organic waste can be converted into biogas and soil improver using anaerobic digestion. Here organic wastes are broken down by anaerobic microorganisms in biogas plants.
The biogas can be converted into renewable electricity or burnt for environmentally friendly heating. Advanced technologies such as mechanical biological treatment are able to sort the recyclable elements of the waste out before biological treatment by either composting, anaerobic digestion or biodrying.
Sulabh International, an Indian NGO designed a cheap toilet system that recycles human waste into biogas and fertilizer.
Electronics disassembly and reclamation
The direct disposal of electrical equipment — such as old computers and mobile phones — is banned in many areas due to the toxic contents of certain components. The recycling process works by mechanically separating the metals, plastics and circuit boards contained in the appliance. When this is done on a large scale at an electronic waste recycling plant, component recovery can be achieved in a cost-effective manner.
Electronic devices, including audio-visual components (televisions, VCRs, stereo equipment), mobile phones and other hand-held devices, and computer components, contain valuable elements and substances suitable for reclamation, including lead, copper, and gold. They also contain a plethora of toxic substances, such as dioxins, Polychlorinated biphenylsPCBs, cadmium, chromium, radioactive isotopes, and mercury. Additionally, the processing required to reclaim the precious substances (including incineration and acid treatments) release, generate and synthesize further toxic by-products.
In the United States, an estimated 70% of heavy metals in landfills come from discarded electronics.[9]Some regional governments are attempting to curtail the accumulation of electronics in landfills by passing laws obligating manufacturers and consumers to recycle these devices,[10] but because in many cases safe dismantlement of these devices in accordance with first world safety standards is unprofitable,[citation needed] historically much of the electronic waste has been shipped to countries with lower or less rigorously-enforced safety protocols.
Places like Guiyu, China dismantle tons of electronics every year, profiting from the sale of precious metals, but at the cost of the local environment and the health of its residents.[11][12]
Mining to produce the same metals, to meet demand for finished products in the west, also occurs in the same countries, and the United Nations Conference on Trade and Development (UNCTAD) has recommended that restrictions against recycling exports be balanced against the environmental costs of recovering those materials from mining. Hard rock mining in the USA produces 45% of all toxics produced by all USA industries (2001 US EPA Toxics Release Inventory).
Printer ink cartridges & toners
Printer ink cartridges can be recycled. They are sorted into different brands and models which are then resold back to the companies that created these cartridges. The companies then refill the ink reservoir which can be sold back to consumers. Toner cartridges are recycled the same way as ink cartridges, using toner instead of ink. This method of recycling is highly efficient as there is no energy spent on melting and recreating the recycled object itself.
Ferrous metals
Iron and steel are the world's most recycled materials, and among the easiest materials to recycle, as they can be separated magnetically from the waste stream. Recycling is via a steelworks: scrap is either remelted in an Electric Arc Furnace (90-100% scrap), or used as part of the charge in a Basic Oxygen Furnace (around 25% scrap).[13] Any grade of steel can be recycled to top quality new metal, with no 'downgrading' from prime to lower quality materials as steel is recycled repeatedly. 42% of crude steel produced is recycled material.[14]
Non-ferrous metals
Aluminium is shredded and ground into small pieces or crushed into bales. These pieces or bales are melted in an aluminium smelter to produce molten aluminium. By this stage the recycled aluminium is indistinguishable from virgin aluminium and further processing is identical for both.
Due to the high melting point of aluminium ore, large amounts of energy are required to extract aluminium from ore, making the environmental benefits of recycling aluminium enormous.
Recycling aluminium only results in approximately 5% of the CO2 that would be released during the production of raw aluminium.[15] The percentage is even smaller when considering the complete cycle of mining and transporting the aluminium. Also, as open-cut mining is most often used for obtaining aluminium ore, mining destroys large sections of natural land.
An aluminium can is 100% recyclable. Every time a can is recycled, enough energy is saved to power a television for about three hours (compared to mining and producing a new can).[16]
Glass
Glass bottles and jars are gathered via curbside collection schemes and bottle banks, where the glass may be sorted into color categories. The collected glass cullet is taken to a glass recycling plant where it is monitored for purity and contaminants are removed. The cullet is crushed and added to a raw material mix in a melting furnace. It is then mechanically blown or molded into new jars or bottles. Glass cullet is also used in the construction industry for aggregate and glassphalt. Glassphalt is a road-laying material which comprises around 30% recycled glass.
Glass can be recycled indefinitely as its structure does not deteriorate when reprocessed.
Paper
Recycled paper is made from waste paper, usually mixed with fresh wood pulp. If the paper contains ink, it must be deinked. This also removes fillers, clays, and fiber fragments.
Almost all paper can be recycled today, but some types are harder to recycle than others.
Papers coated with plastic or aluminum foil, and papers that are waxed, pasted, or gummed are usually not recycled because the process is too expensive. Gift wrap paper also cannot be recycled. Different types of paper are usually sorted before recycling, such as newspapers and cardboard boxes.
Different grades of paper are recycled into different types of new products. Old newspapers are usually made into new newsprint, egg cartons, or paperboard. Old corrugated boxes are made into new corrugated boxes or paperboard. High-grade white office paper can be made into almost any new paper product: stationery, newsprint, magazines, or books.
Sometimes recyclers ask for the removal of the glossy inserts from newspapers because they are a different type of paper. Glossy inserts have a heavy clay coating that some paper mills cannot accept. Most of the clay is removed from the recycled pulp as sludge which must be disposed. If the coated paper is 20% by weight clay, then each ton of glossy paper produces more than 200 kg of sludge and less than 800 kg of fiber. Uncoated (no clay), recycled newsprint gives less sludge and more useable fiber.
Paper can only be recycled a finite number of times due to the shortening of paper fibers making the material less versatile. Often it will be mixed with a quantity of virgin material, referred to as downcycling. This does not however exclude the material from being used in other processes such as composting or anaerobic digestion, where further value can be extracted from the material in the form of compost or biogas.
Plastic
Plastic recycling is the process of recovering scrap or waste plastics and reprocessing the material into useful products. Compared to glass or metallic materials, plastic poses unique challenges - because of the massive number of types of plastic, they each carry a resin identification code, and must be sorted before they can be recycled. This can be costly - while metals can be sorted using electromagnets, no such 'easy sorting' capability exists for plastics. In addition to this, while labels do not need to be removed from bottles for recycling, lids are often made from a different kind of non-recyclable plastic.
Plastics recycling rates lag far behind those of other items, such as newspaper and aluminium; consumers are typically unsure of how to recycle plastics, and compared to paper and metals fewer recycling facilities exist.
Textiles
When considering textile recycling one must understand what the material consists of. Most textiles are composites of cotton (biodegradable material) and synthetic plastics. The textile's composition will affect its durability and method of recycling.
Workers sort and separate collected textiles into good quality clothing and shoes which can be reused or worn. There is a trend of moving these facilities from developed countries to developing countries.[17]
Damaged textiles are further sorted into grades to make industrial wiping cloths and for use in paper manufacture or material suitable for fibre reclamation and filling products. If textile reprocessors receive wet or soiled clothes however, these may still be disposed of in a landfill, as the washing and drying facilities are not present at sorting units. [18]
Fibre reclamation mills sort textiles according to fibre type and colour. Colour sorting eliminates the need to re-dye the recycled textiles. The textiles are shredded into "shoddy" fibres and blended with other selected fibres, depending on the intended end use of the recycled yarn. The blended mixture is carded to clean and mix the fibres and spun ready for weaving or knitting.
The fibres can also be compressed for mattress production. Textiles sent to the flocking industry are shredded to make filling material for car insulation, roofing felts, loudspeaker cones, panel linings and furniture padding.
Timber
Recycling timber has become popular due to its image as an environmentally friendly product, with consumers commonly believing that by purchasing recycled wood the demand for green timber will fall and ultimately benefit the environment. Greenpeace also view recycled timber as an environmentally friendly product, citing it as the most preferable timber source on their website. The arrival of recycled timber as a construction product has been important in both raising industry and consumer awareness towards deforestation and promoting timber mills to adopt more environmentally friendly practices.
Other Techniques
Several other materials are also commonly recycled, frequently at an industrial level.
Ship breaking is one example that has associated environmental, health, and safety risks for the area where the operation takes place; balancing all these considerations is an environmental justice problem.
Tires are also commonly recycled. Used tires can be added to asphalt, producing road surfaces that are more durable, create less traffic noise, and absorb precipitation better than traditional asphalt[citation needed]. Tires can also be used to make rubber mulch, which is used on playgrounds for safety.
Metal scavenged from automobiles can also be recycled at an industrial scale.
International Universal Recycling Codes
The communication and identification are laid out in International Universal Recycling Codes.
These codes outline what material an item is made from, to facilitate easier reprocessing.
See also
Anaerobic digestion
Composting
Downcycling
Recyclable waste
Materials Recovery Facility
Regiving
Pollution Prevention
Cheapcycle
Re-use
Types of recycling
Full Depth Recycling
Ship-Submarine recycling program
Thermal depolymerization
Chemical reclamation, for example hydrochloric acid regeneration
General topics
Environmentalism
Energy conservation
Waste management
Extended producer responsibility
Pay As You Throw
Recycling in the United States
Trade associations
International Solid Waste Association
Solid Waste Association of North America
Chartered Institute of Wastes Management
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