We have known for many years that our society needs to change from a linear to a circular economic system. The basic principle is to maximise the service life, reuse and recycling of products.
In the construction industry, too, more and more attention is being paid to the issue of the recyclability of building materials. In some areas, recycling and thus the return of building products is now standard practice. Nevertheless, there is still a lot to do. Especially with regard to glass as a building material.
In Germany, around 1.67 million tonnes of flat glass are produced for the construction industry every year, while around 521,000 tonnes of glass cullet are generated. These cullets are made up of 350,000 tonnes from the ‘end of life’ of buildings and 171,000 tonnes from further processing. Due to the long lifespan of glazing and the fact that many of today's cullet originates from the 1970s to 1990s, the amount of cullet produced is relatively low compared to production.
Only 19% of the cullet, around 101,000 tonnes, is returned to flat glass production. Clean separation of materials on construction sites is therefore crucial in order to increase the recycling rate.
At present, too little attention is paid to glass as a material in terms of glass recycling, and not just in demolition and modernisation projects. Ways must be found to separate materials more carefully on the construction site. Some float glass manufacturers are already trying to identify demolition and refurbishment projects at an early stage in order to organise individual collections of the old glass panes. However, institutionalised channels would certainly also be helpful here.
The glass industry has been recycling cullet from production for decades. In the future, methods must be developed to return glass from demolition and dismantling projects back into the cycle. All parties involved are called upon to
to work together. Partnerships between manufacturers and processors, construction companies and demolition companies, flat glass manufacturers and suppliers of new products could further improve the recycling process.