Tuesday, July 10, 2012

PAPER RECYCLING

 PAPER RECYCLING




Paper is different from other waste produce because it comes from sustainable resources: trees. Unlike the minerals and oil used to make plastics and metals, trees are replaceable. Paper is also biodegradable, so it does not pose as much threat to the environment when it is discarded. While 45 out of every 100 tonnes of wood fibre used to make paper in Australia comes from waste paper, the rest comes directly from virgin fibre from forests and plantations. By world standards this is a good performance since the world-wide average is 33 per cent waste paper. Governments have encouraged waste paper collection and sorting schemes and at the same time, the paper industry has responded by developing new recycling technologies that have paved the way for even greater utilisation of used fibre. As a result, industry’s use of recycled fibres is expected to increase at twice the rate of virgin fibre over the coming years.

Already, waste paper constitutes 70% of paper used for packaging and advances in the technology required to remove ink from the paper have allowed a higher recycled content in newsprint and writing paper. To achieve the benefits of recycling, the community must also contribute. We need to accept a change in the quality of paper products; for example stationery may be less white and of a rougher texture. There also needs to be support from the community for waste paper collection programs. Not only do we need to make the paper available to collectors but it also needs to be  separated into different types and sorted from contaminants such as staples, paperclips, string and other miscellaneous items.

There are technical limitations to the amount of paper which can be recycled and some papers cannot be collected for re-use. These include paper in the forms of books and permanent records, photographic paper and paper which are badly contaminated. The four most common sources of paper for recycling  are factories and retail stores which gather large amount of packaging material in which goods are delivered, also offices  which have unwanted business documents and computer output, paper converters and printers and lastly households which discard newspapers and packaging material. The paper manufacturer also incurs the collection cost.

One collected, the paper has to be sorted by hand by people trained to recognise various types of paper. This is necessary because some types of paper can only be made from particular kinds of recycled fiber. The sorted paper then has to be rippled or mixed with water and broken down into its individual fibres. This mixture is called  stock and may contain a wide variety of contaminating materials, particularly if it is made from mixed waste paper which has had little sorting. Various machines are used to remove other materials from the stock. After passing through the repulsing process, the fibres from printed waste paper are grey in color because the printing ink has soaked into the individual fibers. This recycled material can also be used in products where the grey colour is not acceptable, the fibres must be de-inked. This involves adding chemicals such as caustic soda or other alkalies, soaps and detergents, water hardening agents such as calcium chloride, frothing agents and bleaching agents. Before the recycled fibres can be made into paper they must be refined or treated in such a way that they bond together.

Most paper products must contain some virgin fiber as well as recycled fibres and unlike glass, paper cannot be recycled indefinitely. Most paper is down-cycled which means that a product made from recycled paper is of an inferior quality to the original paper. Recycling paper is beneficial in that it saves some of the energy, labor and capital that go into producing virgin pulp. However, recycling requires the use of fossil fuel, a non- renewable energy source, to collect the waste paper from the community and to process it to produce new paper. And the recycling process still creates emissions which require treatment before they can be disposed of safely. Nevertheless, paper recycling is an important economical and environmental practice but one which must be carried out in a rational and viable manner for it to be useful to both industry and the community.

 

1 comment:

  1. I learned so much from this post. Lets promote computer recycling as a means of proper waste disposal. In this way, we can help save the environment.

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