- At the recycling plant, a glass recycling machine breaks the glass into smaller, workable shards. It filters out unwanted container parts such as metal caps, labeling or plastic neck rings. A series of magnets (for metal), vacuums (for paper and plastic labels) and screens (for debris) separate the materials from the glass. After filtering and crushing, the glass is called cullet.
- The cullet is mixed with soda ash, limestone and sand in preparation for creating new glass. The amount of each additive depends on the desired strength and use of the new glass. The color of the glass stays the same. So, if green glass was used to crate the cullet, green glass is produced at the end of the recycling process. The additives are the raw materials used to create glass. By mixing these with the used glass, more glass is produced using less energy.
- To reform the cullet and additional ingredients into new glass, they must be blended together in a furnace and returned to a molten state. The furnace temperature can reach 2,700 degrees Fahrenheit. After firing, the glass can be reblown to create new containers. The recycling and recreating process can go on indefinitely.
- A typical glass recycling plant can recycle up to 20 tons of glass per hour, or 160 tons in an eight-hour day. How long a particular piece of glass takes to be recycled depends on a number of factors, including curbside pick-up time, transportation time, sorting and rerouting time and need for a particular type or color of glass. A glass container generally returns to the store shelf within 30 days from the beginning of the recycling process.
- Besides being molded into new containers, recycled glass before and after firing has a number of uses. In its crushed form, recycled glass is used in road asphalt, kitchen counter tops and home décor such as picture frames and tiles. In a completely crushed form (sand), glass can be used to replenish beaches where wind erosion has depleted the sand.
