Реферат Almost anything can be recycled, but certain things are more common
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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 and filters then remove things like staples, glues and other unwanted chemicals from the pulp. The ink is removed by either a chemical wash, or by blowing the ink to the surface where it's skimmed off. The pulp -- which may be bleached -- is then sprayed and rolled into flat sheets, which are pressed and dried. Sometimes new pulp is added to the recycled pulp to make the paper stronger. The giant sheets of paper, when dry, are then cut into the proper size for resale back to consumers [source: Essential Guide].
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
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.
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).[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]
[edit]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,[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]
[edit]Landfill use
About 35% of municipal solid waste (before recycling) by weight is paper and paper products.[14] Recycling 1 ton of newspaper eliminates
[edit]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.[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
[edit]Criticism
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.
[edit]Recycling facts and figures
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
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:
§ The average per capita paper use worldwide was
§ 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)]
§ Recycling 1 short ton (0.91 t) of paper saves 17 mature trees, 7 thousand US gallons (
§ 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.[23]
§ 115 billion sheets of paper are used annually for personal computers.[24] The average web user prints 28 pages daily.[25]
§ Most corrugated fiberboard boxes have over 25% recycled fibers[citation needed]. Some are 100% recycled fiber.
[edit]Paper recycling by region
[edit]European Union
Paper recovery in
[edit]Japan
Municipal collections of paper for recycling are in place. However, according to theYomiuri Shimbun, in 2008, eight paper manufacturers in
[edit]United States of America
Recycling has long been practiced in the
§ 1690: The first paper mill to use recycled linen was established by the Rittenhouse family.[28]
§ 1896: The first major recycling center was started by the Benedetto family in
§ 1993: The first year when more paper was recycled than was buried in landfills.[29]
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
By 1998, some 9,000 curbside programs and 12,000 recyclable drop-off centers had sprouted up across the
In 2008, the global financial crisis resulted in the price of old newspapers to drop in the
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
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.
Why bother?
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In 2003/04, paper and card accounted for almost a third of all household waste collected for recycling, with almost 1.3 million tonnes being collected in
Although the raw material for making paper is predominantly trees, it is a common misconception that recycling waste paper saves trees. Trees are grown for commercial use and harvested as a long term crop with new trees planted to replace those cut down. In addition, papermakers are able to use the parts of the trees that cannot be used in other industries such as construction and furniture making. Different species of trees provide fibres that are used in different types of paper. Coniferous softwoods such as spruce, pine birch and cedar produce fibres which are long (average fibre length is 3mm) and are used to make papers which have a lot of strength. Hardwoods such as birch and aspen do not grow as fast as softwoods and produce short fibres (average fibre length 1mm) which are used for bulky papers such as writing paper and fluting, which is the middle part of cardboard. Nearly all paper is made from wood grown in these "sustainable" forests. The more important environmental issues are:
1. The nature of forests and where they are situated. As the demand for paper has increased, more timber has been needed to meet the demand for wood pulp. In some cases this has meant the loss of valuable wildlife habitats and ecosystems, as old forests have been replaced by managed plantations, usually of fast-growing conifers. The lack of tree species diversity in managed forests has a direct impact on the biodiversity of the whole forest.
2. By using waste paper to produce new paper disposal problems are reduced.
For every tonne of paper used for recycling the savings are:
o at least 30000litres of water
o 3000 - 4000 KWh electricity (enough for an average 3 bedroom house for one year)
o 95% of air pollution.
- Producing recycled paper involves between 28 - 70% less energy consumption than virgin paper and uses less water. This is because most of the energy used in papermaking is the pulping needed to turn wood into paper.
- Recycled paper produces fewer polluting emissions to air (95% of air pollution) and water. Recycled paper is not usually re-bleached and where it is, oxygen rather than chlorine is usually used. This reduces the amount of dioxins which are released into the environment as a by-product of the chlorine bleaching processes.
- Paper is a biodegradable material. This means that when it goes to landfill, as it rots, it produces methane, which is a potent greenhouse gas (20 times more potent than carbon dioxide). It is becoming increasingly accepted that global warming is a reality, and that methane and carbon dioxide emissions have to be reduced to lessen its effects. Please see our energy information sheet for more information on this.
What are the main types of paper in everyday use which can be recycled?
- Office white paper
- Newspapers, magazines, telephone directories and pamphlets
- Cardboard
- Mixed or coloured paper
- Computer print out paper
If you have junk mail, windowed envelopes, or Yellow Pages then please contact you local authority. These materials can be more awkward to recycle, and the availability of recycling facilities varies around the country.
There are also different grades of paper and board collected mainly from agricultural and industrial sources. There are actually about 50 different grades for paper recycling companies to grapple with! You can find details of the other grades here on this website: www.letsrecycle.com/materials/paper/specifications.jsp
What can I do to reduce the amount of paper being wasted?
- Try not to use as much in the first place! Use the back of sheets of paper as well as the front - look to see if that piece of paper you were going to put in the bin could be used as scrap paper for many uses eg to make a shopping list, to jot down your dental appointment or to leave a note for someone.
- Buy recycled paper products wherever possible.
Fibre from recycled telephone directories and yellow pages is being used to make egg cartons, cat litter, jiffy bags and animal bedding among other things!
- Reuse envelopes - sticky labels to cover the old address and re-seal the envelope are widely available, also made from recycled paper. Many charities sell them, so you can support them at the same time.
- Playgroups and schools may appreciate being given odd rolls of wallpaper, or any other kind of paper, for painting on or for other uses in the classroom. They are also often glad to receive newspapers to cover the tables for craft activities.
- When you buy a pint of milk or a soft drink, think about the container it is in. Is there an accessible recycling bank for the packaging, or might you end up throwing it away? It would be better to choose the product in the container you know you can dispose of locally for recycling.
- Contact The Mailing Preference Service (details under further contacts) to avoid receiving unsolicited mail.
- By putting a "no junk mail" sign by your letterbox you can cut junk mail such as pizza delivery leaflets by around 90%.
- Contact the BioRegional Development Group for information about paper made from fibres other than wood pulp.
Where can I take paper for recycling?
If your council doesn't pick up paper for recycling via a kerbside scheme, they may have some collection points for newspaper, magazines and telephone directories. For example, there may be paper banks at shopping centres and at civic amenity sites. Go to http://www.recyclenow.com/. This website allows you to obtain a list of the nearest recycling banks to you. All you have to do is enter your postcode to find your nearest recycling banks!
The Yellow Pages Directory Recycling Scheme offers a freephone recycling helpline - 0800 671 444 - which provides advice on where and how to recycle old Yellow Pages directories. Opportunities to recycle the old Yellow Pages range from kerbside schemes and recycling banks at local supermarkets and bring sites, to schools recycling initiatives as part of the Yellow Woods Challenge - http://www.yellow-woods.co.uk/. Please see the further information further information section for further details.
If you do not have a kerbside collection, or local drop off scheme, then make your visits to collection points as you are passing - don't make a special journey in the car to take any materials for recycling - you could be using more energy and causing more atmospheric pollution than you are saving!
What about large quantities of paper, such as that collected by offices?
There are many waste paper merchants and national paper collection companies which will collect a quantity of paper for recycling. In the first instance contact whoever is already dealing with your normal waste, as many waste management companies now also provide recycling services. Alternatively, a quick scan through the local business directory should provide some numbers for recycling collectors.
What about milk and juice cartons made from paper? Can they be recycled?
Cartons are not made from paper alone but comprise of about 75% paper, 20% plastic (polyethylene) and 5% aluminium foil. As they are an amalgam of materials, they cannot be recycled along with ordinary paper. They can be reprocessed into other items or incinerated to produce energy, or landfilled. There are very few collection points for the reprocessing of such cartons in this country, although a reprocessing plant was recently constructed in
Why should I buy recycled paper products?
The future of recycling ultimately depends on there being a market for the materials collected. Recycling is not just collecting materials and taking them to the recycling bank, it is about "closing the loop" and buying recycled too. Paper mills cannot continue to produce recycled paper if people do not buy items made from it.
Where can I buy recycled paper products?
Recycled paper made up 75.5% of the raw materials for UK
Most supermarkets and high street stationers now sell a range of recycled products, such as writing paper, notebooks, file paper, diaries with recycled paper content, calendars, paper tablecloths and napkins, tissues, toilet rolls, kitchen paper and other items. If you cannot see the product you want and you think it could be available made from recycled materials, ask if the shop intends to stock such things in the future - if a lot of people ask, it may encourage the shop to add to its recycled range. The retailer needs to have an incentive to stock the products.
Some charities also sell recycled products such as greetings cards and stationery through their mail order catalogues. Contact the ones you would be interested in supporting and ask if they have a catalogue.
Many printers and office stationery suppliers now use or sell recycled paper. You could ask your usual supplier to make it available, or look in the Yellow Pages for local suppliers.
WRAP produces the Recycled Products Guide which lists recycled products available in this country. Visit the site at http://www.recycledproducts.org.uk/ or call WRAP on 08080 1002040 for further details.
What about the ink on the paper collected? How is it removed?
Sometimes the ink is not removed from the paper when it is reprocessed. The ink is dispersed into the pulp, discolouring it slightly, which is why recycled paper can have a greyish tinge. If the paper is to be de-inked, this can be done in one of two ways, by washing or flotation.
Washing - As the paper is pulped, chemicals can be added which separate the ink from the paper and allow it to be washed away in the large amounts of water used. (The water can then be cleaned and re-used.)
Flotation - Air can be passed through the pulp, producing foam which will hold at least half of the ink and can be skimmed off.
Sometimes the pulp is also bleached; hydrogen peroxide and chlorine are commonly used bleaches, though the former is the more acceptable as it breaks down into water and oxygen on disposal. Chlorine can combine with organic matter under certain conditions to produce organo carbons, including dioxins, which are toxic pollutants.
Although the de-inking process uses water and chemicals, it is still less harmful to the environment than the manufacturing process of new paper.
If you are buying paper in bulk for an office or business, it is worth looking for a supplier who can tell you what the recycled fibre content is, and whether it has been bleached using chlorine, as this is best avoided.
Paper is one of the easiest materials to recycle. Paper is collected from our kerbside or recycling banks by local authorities and waste management companies. Once the paper is collected it is then: Sorted, graded and delivered to a paper mill. Once at the paper mill it is added to water and then turned into pulp. The paper is then screened, cleaned and de-inked through a number of processes until it is suitable for papermaking. It is then ready to be made into new paper products such as newsprint, cardboard, packaging, tissue and office items. It can take just seven days for a newspaper to go through the recycling process and be transformed into recycled newsprint which is used to make the majority of
Recycling a single run of the Sunday New York Times would save 75,000 trees.
If all our newspaper was recycled, we could save about 250,000,000 trees each year!
If every American recycled just one-tenth of their newspapers, we would save about 25,000,000 trees a year.
If you had a 15-year-old tree and made it into paper grocery bags, you'd get about 700 of them. A busy supermarket could use all of them in under an hour! This means in one year, one supermarket can go through over 6 million paper bags! Imagine how many supermarkets there are just in the
The average American uses seven trees a year in paper, wood, and other products made from trees. This amounts to about 2,000,000,000 trees per year!
The amount of wood and paper we throw away each year is enough to heat 50,000,000 homes for 20 years.
Approximately 1 billion trees worth of paper are thrown away every year in the
Americans use 85,000,000 tons of paper a year; about
The average household throws away 13,000 separate pieces of paper each year. Most is packaging and junk mail.
In 1993,
Each ton (
The 17 trees saved (above) can absorb a total of
The construction costs of a paper mill designed to use waste paper is 50 to 80% less than the cost of a mill using new pulp.
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