Paper recycling is the process of turning waste paper 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 but was discarded before it was ready for consumer use. Post-consumer waste is material discarded after consumer use, such as old corrugated containers (OCC), old magazines, old newspapers (ONP), office paper, old telephone directories, and residential mixed paper (RMP).[2] Paper suitable for recycling is called "scrap paper", often used to produce molded pulp packaging. The industrial process of removing printing ink from paperfibers of recycled paper to make deinked pulp is called deinking, an invention of the German jurist Justus Claproth.
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Industrialized paper making has an effect on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts).[3]
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.[6] 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.[7] 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. 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.[8] It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (81,000 km²) of forestland.[9]
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,[10] while the Bureau of International Recycling (BIR) claims a 64% reduction.[11] Some 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). 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.[12] Recycling paper to make pulp actually consumes more fossil fuels than making new pulp via the kraft process; these mills generate all of their energy from burning waste wood (bark, roots) and byproduct lignin.[13] 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).[14] 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.
About 35% of municipal solid waste (before recycling) by weight is paper and paper products.[15]
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]
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 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.
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]
In Mexico, recycled paper, rather than wood pulp, is the principal feedstock in papermills accounting for about 75% of raw materials.
This article incorporates public domain material from the United States Government document "http://www.epa.gov/epaoswer/non-hw/muncpl/recycle.htm".
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