Recycling paper is a series of processes that convert waste paper into new materials usable again. The lack of basic materials and human need has generated his desire to invent ways to cover the shortfall or downgraded. Vhajth to rubber, plastic and paper led him to the idea of recycling until the economy and good use of these materials , minimizing waste any McCabe preservation of the environment .
This idea began during World War I and II , and this is what the legacy of pollution , and the large number of scattered waste , where the waste collected for re-use , and with the passage of time has become a process of re- industrialization of the most important methods used in the management of solid waste for their environmental benefits . The programs and campaigns carried out by the NGOs interested in the environment played a major role in the expansion of the public thought the issue of recycling because of its great importance has found great reception among students in schools , and even housewives and members of environmental associations .
Was considered remanufacturing direct basic form before the nineties , but with the beginning of the nineties began to focus on re- industrialization indirect , and this improves manufacturing waste to produce other materials based on the same raw material , such as recycled paper and cardboard, plastic, metal , especially aluminum and others.
Paper recycling process
Main article: deinking
The process of paper recycling involves mixing used paper with water and chemicals to break it down. It is then chopped up and heated, which breaks it down further into strands of cellulose, a type of organic plant material; this resulting mixture is called pulp, or slurry. It is strained through screens, which remove any glue or plastic that may still be in the mixture then cleaned, de-inked, bleached, and mixed with water. Then it can be made into new recycled paper.[2The same fibers can be recycled about seven times, but they get shorter every time and eventually are strained out.[3]
Rationale for recycling
Industrialized paper making has an effect on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).]
Today, 90% of paper pulp is created from wood ( in most modern mills only 9-16% of pulp is made from pulp logs the rest from waste wood that was traditionally burnt). Paper production accounts for about 35% of felled trees,[5] and represents 1.2% of the world's total economic output.[6] Recycling one ton of newsprint saves about 1 ton of wood while recycling 1 ton of printing or copier paper saves slightly more than 2 tons of wood.[7] This is because kraft pulping requires twice as much wood since it removes lignin to produce higher quality fibres than mechanical pulping processes. Relating tons 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.[8] 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.[5] Most pulp mill operators practice reforestation to ensure a continuing supply of trees.[citation needed] The Programme for the Endorsement of Forest Certification (PEFC) and the Forest Stewardship Council (FSC) certify paper made from trees harvested according to guidelines meant to ensure good forestry practices.[9] It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (81,000 km²) of forestland.]
Energy
Energy consumption is reduced by recycling,] although there is debate concerning the actual energy savings realized. The Energy Information Administration claims a 40% reduction in energy when paper is recycled versus paper made with unrecycled pulp,] while the Bureau of International Recycling (BIR) claims a 64% reduction.3Some calculations show that recycling one ton of newspaper saves about 4,000 kWh (14 GJ) of electricity, although this may be too high (see comments below on unrecycled pulp) ( recycling paper also produces no free energy in the way of process steam or recovery steam thus making it more expensive to recycle paper than to make new paper[citation needed]). 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.] Recycling paper to make pulp actually consumes more fossil fuels than making new pulp via the kraft process; these mills generate most of their energy from burning waste wood (bark, roots, sawmill waste) and byproduct lignin (black liquor).] Pulp mills producing new mechanical pulp use large amounts of energy; a very rough estimate of the electrical energy needed is 10 gigajoules per tonne of pulp (2500 kW·h per short ton).]
Landfill use
About 35% of municipal solid waste (before recycling) by weight is paper and paper products.]
Water and air pollution
The United States Environmental Protection Agency (EPA) has found that recycling causes 35% less water pollution and 74% less air pollution than making virgin paper.] 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, thus reducing 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.] However, recycling mills may have polluting by-products like sludge. De-inking at Cross Pointe's Miami, Ohio mill results in sludge weighing 22% of the weight of wastepaper recycled.
Recycling facts and figures
n the mid-19th century, there was an increased demand for books and writing material. Up to that 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.
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.
Some statistics on paper consumption:
- The average per capita paper use worldwide was 110 pounds (50 kg).
- It is estimated that 95% of business information is still stored on paper.
- Recycling 1 short ton (0.91 t) of paper saves 17 mature trees, 7 thousand US gallons (26 m3) of water, 3 cubic yards (2.3 m3) of landfill space, 2 barrels of oil (84 US gal or 320 l), and 4,100 kilowatt-hours (15 GJ) of electricity – enough energy to power the average American home for six months.
- 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.
- 115 billion sheets of paper are used annually for personal computers.[27] The average web user prints 28 pages daily.
- Most corrugated fiberboard boxes have over 25% recycled fibers[citation needed]. Some are 100% recycled fiber.
Paper recycling by region
European Union
Paper recovery in Europe has a long history and has grown into a mature organization. In 2004 the paper recycling rate in Europe was 54.6% or 45.5 million short tons (41.3 Mt).[29] The recycling rate in Europe reached 64.5% in 2007, leaving the industry on track to meeting its voluntary target of 66% by 2010.
Japan
Municipal collections of paper for recycling are in place. However, according to the Yomiuri Shimbun, in 2008, eight paper manufacturers in Japan have admitted to intentionally mislabeling recycled paper products, exaggerating the amount of recycled paper used
United States
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]
- 1896: 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.]
Today, over half of all paper used in the United States is collected and recycled.[33] Paper products are still 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 used in the US (or 53.5 million tons) was recovered for recycling.[36] This is up from a 1990 recovery rate of 33.5%.] The US paper industry set a goal of recovering 55 percent of all paper used in the US by 2012. Paper products used by the packaging industry were responsible for about 77% of packaging materials recycled, with more than 24 million pounds recovered in 2005.]
By 1998, some 9,000 curbside recycling programs and 12,000 recyclable drop-off centers existed nationwide. As of 1999, 480 materials recovery facilities had been established to process the collected materials.]
In 2008, the global financial crisis caused the price of old newspapers to drop in the U.S. from $130 to $40 per short ton ($140/t to $45/t) in October.]
Mexico
In Mexico, recycled paper, rather than wood pulp, is the principal feedstock in papermills accounting for about 75% of raw materials.]
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