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The use of paper in industrialized nations continues to increase, in some cases accounting for almost 20 percent of all household garbage [source:Essential Guide]. Although the trees used to make new paper are a renewable resource, old-growth forests are often chopped down to make room for the pulpwood trees, which are quickly planted and harvested to make paper. Recycled paper results in a significant net savings in terms of water and energy used, as well as pollutants emitted into the environment.
Almost anything can be recycled, but certain things are more common.
Paper
The use of paper in industrialized nations continues to increase, in
some cases accounting for almost 20 percent of all household garbage
[source:Essential
Guide]. Although
the trees used to make new paper are a renewable resource, old-growth
forests are often chopped down to make room for the pulpwood trees,
which are quickly planted and harvested to make paper. Recycled paper
results in a significant net savings in terms of water and energy used,
as well as pollutants emitted into the environment.
From curbside and workplace
collections, paper is sorted based on the type of paper, how heavy it
is, what it's used for, its color and whether it was previously recycled.
Then a hot chemical and water bath reduces the paper to a soupy, fibrous
substance. Magnets, gravity an
Glass
Recycling glass represents significant energy and cost savings over
making virgin glass, because there's virtually no down-cycling when
glass is recycled. There are two ways to recycle glass. Some companies
collect bottles from their customers and thoroughly wash and disinfect
them before reuse. Other glass recyclers sort the glass by color (clear,
green and brown glass shouldn't mix because it'll give it a mottled
effect). The glass is ground up into fine bits known as cullet, thoroughly
sifted and filtered using lasers, magnets and sifters, then melted
down and reformed into new glass.
Only glass used in containers like jars and bottles is commonly recycled. Window glass and glass used in light bulbs is too expensive and difficult to recycle.
Steel
The recycling of scrap steel from cars and old buildings has a long history
in the United States. Steel is relatively easy to recycle -- giant machines
shred junk cars and construction waste. In addition, U.S. law requires
a certain proportion of all steel to be made with recycled steel --
all U.S. steel contains at least 25 percent recycled steel.
Once sorted, scrap steel is
melted down and re-refined into huge sheets or coils. These can be shipped
to manufacturers to make car bodies or construction materials.
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 which left the paper mill, which has been discarded before it was ready for consumer use. Post-consumer waste is material discarded after consumer use, such as old magazines, old newspapers, office waste, old telephone directories, and residential mixed paper.[2] Paper suitable for recycling is called "scrap paper". The industrial process of removing printing ink from paperfibers of recycled paper to make deinked pulp is called deinking.
Industrialized paper making has an effect on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).[3] Recycling paper reduces this impact.
Today, 90% of paper pulp is made of wood. Paper production accounts for about 35% of felled trees,[4] and represents 1.2% of the world's total economic output.[5]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.[citation needed] 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.[6] 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.[4] 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.[7] It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (81,000 km²) of forestland.[8]
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,[9] while the Bureau of International Recycling (BIR) claims a 64% reduction.[10]Some calculations show that recycling one ton of newspaper saves about 4,000 kW·h (14 GJ) 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.[11] Recycling paper to make pulp may actually consume more fossil fuels than making new pulp via the kraft process; however, since these mills generate all of their energy from burning waste wood (bark, roots) and byproduct lignin.[12] 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),[13] usually fromhydroelectric generating plants.[citation needed] Recycling mills purchase most of their energy from local power companies, and since recycling mills tend to be in urban areas, it is likely that the electricity is generated by burning fossil fuels.[citation needed]
About 35% of municipal solid
waste (before recycling) by weight is paper and paper products.[14] Recycling 1 ton of newspaper eliminates
3 cubic meters of landfill.[15]Incineration o
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.[16] 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.[17] However, 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.[18]
See also: Recycling
Some of the claimed benefits of paper recycling have fallen under criticism, such as the claim that recycling saves trees, reduces energy consumption, reduces pollution, creates desirable jobs, and saves money.
In 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.[19]
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.[20]
Some statistics on paper consumption:
Paper recovery in Europe has a long history and has grown into a mature organization. The European papermakers and converters work together to meet the requirements of the European Commission and national governments. Their aim is the reduction of the environmental impact of waste during manufacturing, converting/printing, collecting, sorting and recycling processes to ensure the optimal and environmentally sound recycling of used paper and board products. In 2004 the paper recycling rate in Europe was 54.6% or 45.5 million short tons (41.3 Mt).[26]The recycling rate in Europe reached 64.5% in 2007, which confirms that the industry is on the path to meeting its voluntary target of 66% by 2010.[27]
Municipal collections of paper for recycling are in place. However, according to theYomiuri Shimbun, in 2008, eight paper manufacturers in Japan have admitted to intentionally mislabeling recycled paper products, exaggerating the amount of recycled paper used.[citation needed]
Recycling has long been practiced in the United States. The history of paper recycling has several dates of importance:
Today, over half of the material used to make paper is recovered waste.[30] Paper products are the largest component of municipal solid waste, making up more than 40% of the composition of landfills.[31][32] In 2006, a record 53.4% of the paper used in the US (or 53.5 million tons) was recovered for recycling.[33] This is up from a 1990 recovery rate of 33.5%.[33] The US paper industry has set a goal to recover 55 percent of all the paper used in the US by 2012. Paper packaging recovery, specific to paper products used by the packaging industry, was responsible for about 77% of packaging materials recycled with more than 24 million pounds recovered in 2005.[34]
By 1998, some 9,000 curbside programs and 12,000 recyclable drop-off centers had sprouted up across the US for recycles collection. As of 1999, 480 materials recovery facilities had been established to process the collected materials.[35]
In 2008, the global financial crisis resulted in the price of old newspapers to drop in the US from $130 to $40 per short ton ($140/t to $45/t) in October.[36]
The first piece of paper as we know it was produced from rags in AD 105 by Ts'ai Luin, who was part of the Eastern Han Court of the Chinese Emperor Ho Ti.
Paper is made from cellulose fibre, the source of which can be pulped wood, or a variety of other materials such as rags, cotton, grasses, sugar cane, straw, waste paper, or even elephant dung! In this country, wood pulp is the most common source material for the manufacture of virgin paper, i.e. paper which has no recycled content.
In 2004 recycled paper and board provided about 74% of the source materials for the 6.2million tonnes of paper manufactured in the UK's 76 paper and board mills. A further 7.7 million tonnes were imported.
There are different sources of waste fibre used as a source material for manufacturing recycled paper.
Mill Broke is "waste" paper which has never been used, either printers' off cuts or rolls damaged during production. When mixed with water the fibres are freed into pulp. The National Association of Paper Manufacturers does not recognise a paper as recycled if it contains more than 25% mill broke and/or virgin wood pulp.
The recycling of paper which has been printed on and used is known as "post-consumer waste". It is more problematic, (see de-inking below), but it is still worthwhile. Paper cannot be recycled indefinitely, it can only be recycled 4-6 times, as the fibres get shorter and weaker each time. Some virgin pulp must be introduced into the process to maintain the strength and quality of the fibre, so no matter how much we recycle we will never eradicate the need for virgin fibre.
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