Challenges of the Circular Economy for Composite Packaging

Consumers today expect sustainable packaging as a matter of course, and brand manufacturers are under pressure to meet these expectations. Many see the solution in exchanging plastics for paper.
“Marketing departments are focusing on packaging that consumers perceive as more sustainable. Paper has a better image among consumers than plastic, which can increase sales,” said Till Isensee, Managing Director of Tilisco during an interview on FACHPACK TV. But the reality is more complex, according to the packaging engineer: “Paper alone often cannot provide the necessary protection, which is why plastics have to be integrated.” Thin layers or coatings of polyethylene (PE) and other plastics are often necessary to adequately protect the contents, which makes the packaging less recyclable.

Another problem is how fibre-based composite packaging fits into the circular economy. Isensee cites a study by RWTH Aachen University that showed that around 50% of this fibre composite packaging is disposed of in the blue bin. However, food residues, moisture and microbiological contamination often make the packaging unsuitable for paper recycling. 30% of this packaging ends up in the residual waste and only 20% in the yellow bag, where it actually belongs by definition of the Central Packaging Register Office. “But is fibre composite packaging also optimally recycled via the yellow bin? No,” says Isensee. The reasons for this lie in the high level of contamination with food residues, moisture and microbiological contamination in the yellow bag, which makes paper recycling impossible. In Isensee's opinion, the blue clay is the right disposal route – if it can be proven that it is easily recyclable.

According to Isensee, one strategy of the companies that put packaging into circulation is to keep the plastic content in composite packaging below 5%. This allows them to be licensed for paper recycling. If the proportion is higher, the composite packaging must be disposed of in the yellow sack. “Manufacturers can save on disposal costs by using thin layers of plastic, but this creates new problems,” says Isensee. “The thinner the plastic layers, the more difficult it is to separate them.” The plastic can then settle on the nets of paper machines, for example, and impair the quality of the paper. ‘Paper manufacturers confirm that this is increasingly causing problems,’ says Isensee. In reality, however, according to the study by RWTH Aachen University, consumers are already disposing of 50 % of fibre composite packaging in the blue bin – even with a plastic content of over
5 %. According to Isensee, this is where it is also recycled. However, without the paper processors being reimbursed for it by the dual systems.

While well-known recycling loops are well established for PET bottles and paper, the combination of paper and plastic therefore represents a new challenge for the packaging industry.