Recycling is the process of taking used material and processing it to make something else, or reconditioning an object to restore it to an ''as new'' condition. It is stage three of what has become known as the 3R Concept:
This is considered to be a very environmentally friendly process since in addition to avoiding the waste of potentially useful materials, it reduces the consumption of fresh raw materials and energy usage. Pollution levels are limited because waste material is not incinerated or buried.
Many kinds of materials can be recycled, such as glass, paper, metal, plastics, textiles and electronics, but many highly developed countries have a very poor record with respect to recycling.
About 5% of the world's population live in the United States and on average every US citizen produces about 730 kg of rubbish each year. This is roughly the weight of a heavy draught horse. In total the annual amount of rubbish produced in the US amounts to 228 million tonnes, which is 40% of the world's waste.
In the past ten years the amount of US recycling has approximately doubled and 32.5% of US municipal waste is now recycled, but this still means that approximately 154 million tonnes of rubbish ends up in landfill every year.
In the 27 EU states during 2009 each person generated on average 513 kg of municipal waste, which varied from 316 kg per person in the Czech Republic to 833 kg per person in Denmark. This waste was treated in different ways: 38% went to landfill, 20% was incinerated, 24% was recycled and 18% was composted.
Again this varied from country to country, but Austria was the most environmentally friendly by recycling or composting more than 70% of its municipal waste. Bulgaria on the other hand sent all of its municipal waste to landfill. Germany is the country with the most highly organised recycling system, with 48% of its waste being treated in this way.
The rubbish of today is different to the rubbish of 50 years ago. Today's rubbish contains more materials that don't break down when they are put in the ground, or if they do break down this is likely to take a very long time. An aluminium drink can that is buried in landfill in 2011 will still be a recognisable can in the year 2511.
Packaging material makes up about 25% of all municipal rubbish and most of this can be recycled. Used aluminium cans, melted down, can make new cans that can be on the supermarket shelf within 60 days. Recycling one aluminium can save enough energy to run a TV for three hours.
Steel is another metal that can be recycled. A 60-watt light bulb can run for over a day on the amount of energy saved by recycling a pound of steel.
On average everyone uses up to two pine trees worth of paper each year and it is estimated that half a million trees must be cut down to produce the paper for each week's Sunday newspapers. If all newspapers were recycled, that would save 250 million trees each year. Producing new paper uses almost 65% less energy than recycling old and it takes 390 gallons of oil to produce one tonne of paper.
Glass is the classic recyclable material. It is virtually indestructible, taking about 4,000 years to decompose if buried; yet it can readily be melted down and reformed, but in the UK five out of every sixglass bottles gets thrown away.
Motor oil if disposed of inappropriately can cause serious pollution. A litre of oil can contaminate 2,000,000 gallons of fresh water, yet motor oil never wears out; it just gets dirty. It can be recycled, re-refined and used again, thus reducing our reliance on imported oil.
It is a simple fact that we are running out of space so we can't keep on burying our rubbish, but in some countries recycling is regarded as being a more costly option. This has led to reluctance to move away from traditional means of waste disposal.
Initially this may be the case, but as experience is gained and efficiency improves, costs tend to fall. Also there are economies of scale; small amounts are more expensive to recycle than larger quantities.
But there are more important issues than money.
The release of carbon dioxide into the Earth's atmosphere is a major contributor to global warming. Manufacturing certain products releases far more carbon dioxide into the atmosphere than recycling them. A good example is aluminium. Manufacturing new aluminium goods produces 95% more carbon dioxide than recycling scrap aluminium. When you consider that the US alone uses 80 billion cans a year that is an awful lot of aluminium and if all the used cans in the world could be recycled a significant reduction in emissions could be achieved.
Recycling paper can also bring a major environmental benefit. It is estimated that each year every tree in the world absorbs almost 250 pounds (113.5 kg) of carbon dioxide from the Earth's atmosphere, using this to feed itself through a process of photosynthesis. Since it takes about 16 trees to make a tonne of paper, the maths speaks for itself.
Air pollution is a major problem in the world. Huge amounts of toxic gases are released into the air from industries manufacturing items from plastic and metals. As the world population continues to increase, demand for these goods also continues to rise. In the US 2.5 million plastic bottles are thrown away every hour. Without recycling the only option is to build more factories, leading to further pollution.
Recycling could also solve many of the problems associated with landfill. Traditionally rubbish was simply dumped in landfill sites, but in the last 50 years not only has the population increased, but the amount of rubbish generated per person has also increased. We have now reached the situation where many areas are running out of sites suitable for landfill. This is reaching crisis point in some cities and suburbs, where landfills are creeping closer to crowded human settlements, with all the associated risks of disease.
Water is vital to life, but it is very easily contaminated and in many cases this contamination is associated with landfill. When waste is disposed of in landfill it is not treated in any way and contaminants seep down to lower levels of the soil and contaminate the groundwater.
Where landfill areas are scarce, there is often little choice but to dump rubbish into seas and oceans. It is well known that the dumping of industrial and municipal waste in this way has a devastating effect on marine ecology and environmental preservation would be an important benefit of recycling.
It's a simple fact that because we cannot carry on burying or burning rubbish for ever we need to increase the amount of rubbish that is being recycled. Governments can introduce rules and regulations, but the most important issue is to persuade people that recycling is now an essential part of life.
We live in a ''throw away society'' and in spite of all the evidence; many people still need to be convinced of the importance of recycling rubbish. Studies have shown that those with friends and neighbours who recycle are more likely to recycle their own rubbish. Those of us who share this passionate belief have an important task on hand.