Crushing – Once at a recycling facility, the glass is crushed. Crushed glass is called cullet.
Cleaning – Cullet goes through several processes to remove items that are not glass. To remove ferrous (magnetic) metal, the cullet passes under a strong magnet which removes ferrous metals like tin cans, steel or iron. To remove non-ferrous (non-magnetic) metal, the cullet passes by powerful air jets which separate the metal pieces from the glass. Lightweight items, like paper, are removed by a vacuum. Other, non-glass, items are removed by hand.
Separating – Containers must be sorted to separate the clear glass from the colored glass. Only clear glass can be used to make new clear glass. Some glass is sorted by hand while other cullet is sorted with optical sorting systems which separate flint (clear glass), green glass, and amber (brown) glass.
Making new glass – To make new glass, cullet goes into a furnace where it melted at a temperature of 1500ºC. Recycled glass is melted at a lower temperature then virgin materials, which saves 30% of the energy used. The high temperature turns the cullet into molten glass. This molten glass is then shaped into new bottles and jars.
