The company is facing up to the tasks of the future together with its partners and customers. Solutions that stand for the sense of responsibility can be found at the trade fair stand at glasstec 2022, Hall 11, Stand A24. A current example is the elaborate cullet recycling.
In order to reduce its CO2 footprint, Saint-Gobain Glass wants to increase the recycled content in its products from currently 11 to 20 per cent by 2025. A sporting target. To achieve this, the glass manufacturer needs three things: cullet, cullet and, above all, cullet.
Franz Parulewski, Circular Economy Manager at Saint-Gobain Glass, takes care of the cullet. It is about their recycling in the production of new flat glass and their separation from impurities. Above this is the global function of reducing energy consumption and CO2 emissions. Circular economy is a central demand of our time. In addition to curbing the use of resources, it helps to reduce energy consumption and emissions in the production of basic materials, thus counteracting climate change.
Increased recycled content in glass
Saint-Gobain
Saint-Gobain
Against this background, Saint-Gobain Building Glass has developed its own sustainability strategy. The core of this carbon roadmap is to increase the proportion of recycled material in glass. To achieve this, cullet is fed into the glass melt during the production of flat glass.
"With cullet we can make our industry more sustainable," asserts Parulewski. "With 1 tonne of it we reduce CO2 emissions by 300 kg and with 1 per cent cullet in the batch we save 0.3 per cent energy. Cullet is the strongest operational lever we have." That's why Saint-Gobain Glass plans to significantly increase the amount of cullet used in the production of flat glass in the coming years.
See also: First workshop on flat glass recycling
At the moment, Saint-Gobain Glass obtains its cullet mainly from glass production and processing. This is primarily broken glass and offcuts from companies that process the flat glass supplied by Saint-Gobain. The cullet is unmixed, clean and of high quality. But that will not be enough to achieve the desired goal.
Saint-Gobain
Where are the critical points?
Saint-Gobain
There are two problems in recycling flat glass. First, the cullet currently goes mainly to the container glass industry and is recycled into insulation material, for example, or it is used as backfill material in road construction. In both cases they are lost to the flat glass industry. The big function will be to redirect this material flow and make it accessible for flat glass production.
This will only work with new services and effective processes, which Saint-Gobain is currently developing in this area. For example, the recycling of an old facade and the associated positive environmental impact could be accounted for, or the added value for the project developer could be increased through more effective recycling solutions. Recycling must be included in the specifications from the beginning.
High-quality cullet is key to recycling
The second problem is the poor quality of the cullet. The challenge in deconstructing buildings is that the cullet must not be contaminated - neither by debris, nor by unsuitable
cullet.
Also interesting: Remondis and Schüco join forces for the recycling market
This is where Saint-Gobain Glass seeks cooperation with leading recyclers and demolition companies to ensure good quality. In the practical process, the glass panes or cullet arrive at the recycler from the construction site and are broken down to a maximum piece size of 2 cm. This is followed by manual sorting, during which larger impurities such as bolts and fittings are removed. Then the material is sieved and freed from foil residues.
Flagship projects already implemented
Finally, an optical scanner sorts the shards according to colour and a so-called eddy current detector removes metallic impurities. After this complex process, the quality of the material is so good that the cullet can be reused in production.
Lasse Olsson Photo
Saint-Gobain Glass has already implemented promising projects. For example, at the former headquarters of the airline SAS in Stockholm. In the second showcase project, the car manufacturer Audi approached Saint-Gobain and asked whether it was possible to recycle windscreens. "After an initial cautious reaction, we were then convinced that it was possible," recalls Parulewski.
From recycling to reuse
Not only with regard to the environment, but also with regard to rising material prices and the availability of raw materials, the recycling and reuse of glass and building elements will become important pillars of the glass and facade industry. The picture on the left shows a building where the old glass was melted down to make the new facade glass.
You can find Saint-Gobain at glasstec 2022 in Hall 11, Stand A24
