At more than 2,500 year old, glass bottles are one of the oldest forms of packaging. Glass containers can be re-used many times and recycled indefinitely. The three main ingredients in glass are sand, soda ash and limestone. In Australia, most glass produced contains a substantial proportion of recycled glass. There are significant environmental and economic benefits from recycling glass, therefore it is important to recycle glass correctly to avoid contamination.
Why Recycle Glass?
Producing glass from recycled glass rather than raw materials uses 75% less energy. This is largely due to the much lower production temperature, which conserves energy and oil, and extends the life of the furnace. The energy saved by recycling a single bottle could light a 15-watt low energy light bulb for 24 hours. Recycling glass therefore results in a reduction in greenhouse gas emissions. Most glass bottles have generally 40 – 70% recycled content, which means that your bottles and jars go directly into the manufacture of new bottles and jars at an energy saving. For every tonne of glass recycled via kerbside recycling, there is a saving of 560 kg carbon dioxide.2 Furthermore, using recycled glass conserves more than 1.1 tonnes of raw materials per tonne.
What Happens to Glass?
After collection, glass bottles and jars are finely crushed. The majority is melted in a furnace, usually with additional raw materials, to produce glass containers. Glass is infinitely recyclable in this manner. Recycled glass is also used as building aggregate, in water filtration and for building materials.