© Arnaud Serexhe
As Luxembourg's Valorlux system processes record volumes, RTL investigates longstanding public doubts about whether the iconic blue bags truly get recycled as promised.
As part of International Fact-Checking Day, our colleagues from RTL.lu invited readers to submit claims for verification. Among the numerous suggestions, the team prioritised topics related to Luxembourg – including one question about recycling, and more specifically about blue Valorlux recycling bags. This rumour has been circulating on social media for years:
"Blue Valorlux bags are being thrown into the incinerator alongside normal rubbish because the normal rubbish would otherwise not burn very well. What's more, plastic bottles are not suitable for recycling because the plastic is coloured."
Valorlux bags have been around for 29 years
The iconic blue bags have served Luxembourg households for nearly three decades, collected every two weeks for specialised processing. All Valorlux bags are transported exclusively to the Bech-Kleinmacher sorting facility, according to Tobias Wilhelm, waste management specialist at Hein company. With 23 years of experience at the Moselle site, Wilhelm reports record volumes: "We surpassed 14 tonnes of blue bag waste for the first time last year."
© Arnaud Serexhe
This represents a 5% annual increase – outpacing population growth and reflecting both higher consumption and improved recycling participation.
Advanced sorting process
At the Bech-Kleinmacher facility, a sophisticated mechanical system handles the growing waste stream. Delivery lorries arrive every few minutes during peak operations, with specialised presses enabling triple-capacity transport compared to standard vehicles. The materials travel along a kilometre-long conveyor belt network where automated systems sort them into ten distinct categories through sifting, vibration, and air suction technology. Wilhelm explains the subsequent process: "Each material type goes to specialised processors abroad who handle the complete recycling chain –washing, shredding, and pelletising."
Up to 15% of waste in Valorlux bags cannot be recycled
But what about the persistent online claims that blue Valorlux bags frequently end up in incinerators? Valorlux director Claude Turping confirmed to RTL that while 10-15% of blue bag contents cannot be recycled, this material follows an alternative energy recovery process rather than entering standard waste incineration. The non-recyclable materials are for the most part multi-layer plastics and black plastics.
"These byproducts undergo processing into industrial fuel for Luxembourg's cement plants, replacing natural gas through thermal valorisation," Turping explained, stressing, "It's not true that these products or even entire blue bags feed a waste incinerator such as the one in Leudelange, which is operated by SIDOR."
The director clarified that coloured plastic bottles remain fully recyclable unless featuring black pigmentation or additional film layers.
Improper use challenges system
Town halls distribute blue bags for free to local residents. However, some citizens misuse the free blue bags as substitutes for paid black bin liners to dispose of household waste. This means that blue bags are sometimes thrown into black bins, where they do not belong, and thus end up in incinerator plants.
Recycling: Luxembourg 'solidly in the middle'
When assessing national recycling performance, Turping placed Luxembourg in the mid-range among European countries. He noted that cross-border complexities affect metrics, referencing the 200,000+ commuters who purchase goods in Luxembourg but consume them abroad. "For this reason, it's trickier to calculate the quota of countries that have, for instance, a higher import rate," according to Turping.
Conclusion: Blue recycling bags do not end up in incinerators
The investigation confirms Luxembourg's Valorlux system functions as intended: blue bags collected for recycling are processed at a specialised sorting facility, where materials are separated into ten categories before being shipped to dedicated recycling plants abroad. While most contents follow this recycling path, approximately 10-15% of materials – particularly black plastics and multi-layer packaging like crisp bags – cannot be processed through conventional recycling. These non-recyclables are converted into industrial fuel for cement production.
The sole exception occurs when residents improperly use the free blue bags for general household waste, disposing of them in black bins destined for incineration.
