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Recycling involves processing used materials into new products in order to
prevent waste of potentially useful materials
reduce the consumption of fresh raw materials
reduce energy usage
reduce air pollution
reduce water pollution
Once the materials are collected and delivered to a central collection facility, they must be sorted. This is done in a series of stages First, the recyclates are removed from the collection vehicle and placed on a conveyor belt Large pieces of cardboard and plastic bags are removed by hand at this stage Next, automated machinery separates the recyclates by weight, splitting lighter paper and plastic from heavier glass and metal Strong magnets are used to separate out ferrous metals, such as iron, steel, and tin-plated steel cans Finally, glass must be sorted by hand based on its color: brown, amber, green or clear.
Sorting
Concrete recycling
Concrete aggregate collected from demolition sites is put through a crushing machine, often along with asphalt, bricks, dirt, and rocks. Smaller pieces of concrete are used as gravel for new construction projects.
Battery recyclingSome batteries contain toxic heavy metals, making recycling or proper disposal a high priority
Biodegradable waste
Kitchen, garden, and other green waste can be recycled into useful material by composting. This process allows natural aerobic bacteria to break down the waste into fertile topsoil.
Computer recycling
The direct disposal of electrical equipment - such as old computers and mobile phones - is banned in many areas due to the toxic contents of certain components. The recycling process works by mechanically separating the metals, plastics, and circuit boards contained in the appliance.
Steel recyclingIron and steel are the world's most recycled materials, and among the easiest materials to reprocess, as they can be separated magnetically from the waste stream
Glass recyclingGlass bottles and jars are gathered by a curbside collection truck and bottle banks, where the glass may be sorted into color categories.
Paper recyclingPaper can be recycled by reducing it to pulp and combining it with pulp from newly harvested wood. As the recycling process causes the paper fibres to break down, each time paper is recycled its quality decreases.
Tyre recyclingTire recycling is also common. Used tires can be added to asphalt for producing road surfaces or to make rubber mulch used on playgrounds for safety.
Plastic recyclingPlastic recycling is the process of recovering scrap or waste plastics and reprocessing the material into useful products.
Other materialsSeveral other materials are also commonly recycled, frequently at an industrial level.
Ship breaking is one example that has associated environmental, health, and safety risks for the area where the operation takes place; balancing all these considerations is an environmental justice problem.