Where’s secondary packaging going?

The war on packaging waste is fought on many fronts in the beverage industry – from the manufacturers of packaging materials to the bottler. KHS is helping to develop new standards in this field, from which beverage producers and consumers alike are set to profit.

The way to produce more sustainable primary and secondary packaging ever involves two significant lines of approach – recycle and reduce. The first requires that packaging materials are kept in constant circulation by them being reclaimed, processed, and continuously reused. The second entails finding many different ways of using less and less packaging material to save on resources and avoid waste.

Karl-Heinz Klumpe, packaging product manager for KHS in Kleve, says, “The greatest challenge for us is the processability of the packaging materials.” He explains what he means in the following example. “Shrink film made of recycled plastic demonstrates very differently shrinking properties versus film made of new material. As an engineering company, we can’t provide all the answers ourselves but instead, have to coordinate closely with the film manufacturers.”

To this end, KHS is staging several workshops this year. These aim to find out how the percentage of recyclate in the film – as stipulated by the new German Packaging Law, for example – can be increased. “You make a few changes to the chemicals or recipe of your film, and we adjust the airflow or temperature accordingly,” is how Klumpe loosely summarizes the topics up for discussion. “Providing that there’s a standard of quality which is accepted by the big bottlers’ marketing departments, of course. With film made of 100% recyclate, the shrink results aren’t yet satisfactory. Together we still have to work out how to close the gap here between recycling requirements on the one hand and the demand for packs of ever-increasing quality on the other.”

Another avenue film manufacturers are exploring is to reduce the thickness of their film. “The material’s getting thinner and thinner,” states Klumpe. “To provide the same stability, the materials have to be more and more complex. This has its limitations when used for beverage packaging: below a thickness of 35 microns, it’s possible that the price per kilogram for the film then again rises. When it comes down to it, neither bottlers nor their customers want to pay for this.”

Spotlight on the economy

Klumpe well realizes that striving for greater sustainability is often rooted in aspects of the economy rather than ecology. “Everything we do to reduce the amount of material used primarily has a financial motive and aims to cut costs for bottlers. Or – if we’re talking about recycling – film manufacturers, of course, have to continue to develop and adapt so that their business model can be further maintained even in the face of stricter legal requirements.”

What applies to plastics also applies to cardboard – chiefly when it comes to reducing the amount of material used. Paper factories are experimenting with thinner cover layers and lower ridges in the manufacture of corrugated cardboard. “The stability and durability are OK,” assures Klumpe. “However, we have to answer the question of how suitable these materials are for use with machinery. What happens when the cardboard absorbs moisture? If the cardboard is thicker on the outside than the inside, it bends rather like a bimetal and can only be processed on machines with certain restrictions or not at all. What can we do to counteract this?”

Cardboard demands less attention than to plastic, in terms of recycling. Yet here, too, the reuse of this material is an issue, for example, in how far print can affect the recyclability of the paper.

KHS is itself also experimenting with new packaging materials. For instance, a manufacturer from Sweden recently approached the company with a newly developed, award-winning cardboard looking for partners for a market launch. “Our top requirement is that we can be sure that we can process the cardboard without any problems,” Klumpe stresses.

Constant process

The packaging experts in Kleve are also in continuous dialog with the manufacturers of adhesives and adhesive application systems. “Here, we explore how we can avoid having to heat the glue so intensely or how we can reduce our consumption of adhesive,” says Klumpe. “We’re now applying smaller and smaller dots of adhesive as opposed to the diamond shapes we used to use.” All told, sustainable product innovation is a constant process that KHS is undergoing with both proven and new partners. The focus is always on the question of which approach can be adopted to save on materials, time, and energy on the machines.

Shrink tunnel with porous gas burners, for example, can save energy. To heat the air KHS has decided not to use electricity as the energy transfer medium but to work directly with gas to prevent energy that is lost during transport from the producer to the consumer. This process saves up to 50% in energy costs, and almost reduces 60% of CO2 emissions.

In the last few years, KHS has also set standards in many other areas with its resource-saving packaging machines. Both Fully-Enclosed FilmPacks and nested and shifted packs have done away with the need for stabilizing cardboard pads or trays. “We don’t need any more cardboard at all here,” smiles Klumpe. “The taut film gives us a good shrink pattern and a sturdy pack.” In a countermove, the DisplayPacker has also been developed where large packs are placed directly onto cardboard trays without the need for an extra wrapping of stabilizing the film.

However, one of the most outstanding examples of how the material can be reduced is Nature MultiPack. In 2018, Carlsberg Group launched a six-pack of cans under the name of Snap Pack. A few dots of adhesive developed specifically for this pack, which hold the cans together and a stabilizing carrying handle, make any further packaging material redundant. Once the new pack format has been fully rolled out, by eliminating the use of shrink film for cans Carlsberg is set to make plastics saving of up to 76% – that’s more than 1,200 metric tons a year. Danone Waters first made successful use of the Nature MultiPack to launch its prestige PET bottle for Evian in 2016.

“In the development of sustainable packaging, we see ourselves acting as an interface between all those involved and the beverage industry,” Klumpe sums up. “We’re helping to develop new standards which marry ecological demands and legal provisions with bottlers’ economic interests.” A challenge that is sometimes tantamount to the squaring of a circle.