Only totally empty will do

Part 2 of series: Eco-design for plastic packaging and the errors that can be avoided.

“Residual emptying” – this cumbersome term is an important criterion when designing plastic packaging. All too often, however, it is still not taken into consideration. This is not only annoying for us consumers, but also for recyclers.

We have all been there; despite your best efforts, the shampoo bottle, cooking oil bottle, the toothpaste tube (which is too hard) or the body lotion bottle with dispensing mechanism isn’t quite empty. A nuisance for users as they are unable to use the entire product. A big nuisance for plastic recyclers as residues in packaging make it difficult to manufacture high-grade recycling plastics from it for new products.

Food and other types of residual material in packaging can do some damage in the recycling plant. It can lead to adhesions, contaminate the water, which then has to be purified at great expense and it leads to gas and odour formation. This makes the recycling process needlessly expensive and the end product, the regranulate, substandard.

There are currently two big obstacles to high-quality plastic recycling: colour and odour.  Regranulates often have a typically soapy smell, which is an exclusion criterion in many potential applications. There are some technical approaches for removing the odour. However, a workable and, above all, economical solution has not yet been discovered. The associated expense can be largely avoided if the packaging is designed in such a way that it can be emptied without leaving any residue. There is actually no legal provision (as yet) as to how much residue is permitted in packaging. For now, we consumers can only help by choosing products with packaging that makes it possible to use up all the contents.