Recycling rubbish is not only makes economic sense – it also helps the environment. Pollution created by burning rubbish is reduced and valuable resources are saved. Some 75,000 tress would be spared every week just by recycling the Sunday edition of the New York Times.
Many countries encourage recycling new technology allows more and more waste to be reprocessed. Most of the world’s rubbish can be reused – paper, metals, glass, even some plastics.
Plastic is one of the most difficult substances to recycle, because it comes in so many varieties. A plastic tomato-ketchup bottle, for example, consists of six layers of different plastics, each designed to give the bottle certain qualities – shape, strength, flexibility. And as yet there is no simple way to turn an old plastic bottle into a new one.
Plastic can only be turned into a product of lower quality – a plastic lemonade bottle might be cleaned, shredded and used to stuff seat cushions or insulate sleeping bags. A mixture of plastic waste can be recycled into plastic ‘timber’ and used to make durable fencing. But a lot of plastic waste still has to be thrown away because its value as scrap is so low.
Metals are different. Any car on the road today will consist, in part, of earlier cars that have been scrapped and recycled into new steel and other metals.
The more valuable the metal, like gold and silver, the more it pays to recycle it. Aluminium is worth recycling because extracting it from bauxite consumes a huge amount of electricity. Largely thanks to recycling programmes the energy used to make aluminium has fallen by a quarter since the early 1970s.
More than 70 billion canned drinks are bought in America every year, and all the cans are made of aluminium. About half are remelted after use and within six weeks they have been made into new tins and are back on the supermarket shelves.
Glass is worth recovering. The most sensible method is to use glass bottles as often as possible. The average British milk bottle makes about 30 trips to and from the dairy.
Many countries now have compulsory deposit schemes to make people return bottles to shops. When such a law was passed in the state of New York in 1983, it was estimated that within two years it had saved $50 million on rubbish collection, $19 million on waste disposal costs, and about $50 million in energy costs.
Some supermarkets now have machines that accept glass bottles and aluminium cans and give cash or redeemable vouchers to the customer. They read the computer codes on the containers to work out how much to pay.
Broken glass, known as ‘cullet’, can also be recycled, and many countries have bottles banks depend on people’s goodwill. The success of bottle banks varies widely from country to country. The Swiss and Dutch recover 50 per cent of their glass, while in Britain only 12 per cent is recovered.
Glass is best separated by colour, since cullet of mixed colours can be used only to make green glass. Broken glass can be remelted in furnaces and then it can easily be shaped into new bottles or other objects.
Half the world’s waste consists of paper. Many countries import waste paper rather than new pulp for their paper mills. The waste is pulped, cleaned and bleached to remove most of the ink and dirt, before it is turned into new paper in the same way as wood pulp or rags. Japan now makes half its paper by recycling.
Picture Credit : Google