How to make a valuable raw material from waste glass
Glass is one of the oldest artificial materials in the world and is used today in all colors and shapes. In 2017 roughly 7.5 tons of glass were produced in Germany, of which approximately four million were used for glass containers. Roughly, two million tons were processed into so-called flat glass, i.e. into panes and mirrors. A further 402,800 tons were used to make special glasses for household, research and industry Glass is also used as an insulating material: In 2017 almost one million tons of glass wool was produced from the brittle material, and was mainly used in construction.
As glass is also highly valuable as a secondary raw material, the Germans collect waste glass diligently – roughly 2.2 million tons per year. To this end there are roughly 300,000 collection containers in public areas statewide. It is important when collecting glass that the consumer pre-sorts the glass according to color. For this reason the glass containers are divided into white glass, brown glass and green glass. In a few areas there are also colored glass or mixed glass containers. Blue and yellow glass can be disposed of in the containers for green glass. This separation is important, as brown and white glass can be recycled much more efficiently than mixed glass. To recycle white glass shards only three of one thousand bottles can be a different color.
Glass is an excellent material for recycling. It can be melted any number of times and used for new products. Recycled glass shards are the most important raw material in Germany for the new production of glass, which is the reason that now almost all bottles are made up of 60 to 90 percent recycled waste glass. That means huge advantages for the environment: If waste glass shards are used in production, the energy needs sink significantly. This is because the prepared glass shards melt at a lower temperature than the raw materials that are required in the production of new glass. At the same time, glass recycling saves natural raw materials, such as quartz sand, sodium carbonate and limestone.
Glass: Collection and utilization
Statewide we collect waste glass from containers or recycling depots and process it in a highly-technical process into unmixed secondary raw materials. After collection, employees remove course impurities, such as old clothes. Subsequently state-of-the-art optoelectronic sorting machines take over the further sorting process of the smallest impurities, such as porcelain, heat-resistant glasses and glasses containing lead, as well as corks.
We finally make the prepared waste glass available to the glass industry as a secondary raw material.