Nature is sure to appreciate a paper beer bottle

It would really benefit the environment if beer could be sold in containers made of paper, rather than the more conventional materials—i.e. glass, plastic and metal. That is why Thomas Howard, Associate Professor at DTU Mechanical Engineering, has teamed up with a number of his colleagues and the packaging company EcoXpac to start work on developing a ‘Green Fibre Bottle’ for the Danish brewery,Carlsberg.

“We have already set the bar high and stated that what we are looking for is a bottle that can be used for beer. Of course, we will also investigate other, less demanding, areas of application, but our overriding ambition is to create a new beer bottle,” says Thomas Howard.

And it is quite a challenge the partners have taken on. First, the bottle and cap must be able to withstand the pressure from the carbon dioxide beer contains. Second, it must be possible to stack, transport, and handle the new bottle without breaking it. Added to that, it must be possible to make the new bottle quickly in large numbers—given that Carlsberg is the intended purchaser.

“EcoXpac already has a very promising process. The problem at present, however, is that it takes a very long time to make a bottle. If we are to live up to Carlsberg’s requirements, we need a bottle that can be made in just six seconds. At the same time, we have to keep the energy consumption low, otherwise the solution will not be sustainable,” he adds.

The prototype is made of recycled newspaper—i.e. of papier mâché —but the team is also looking at other types of fibre. The paste is poured into a mould, where it then has to dry. In a traditional mould, this takes much longer than six seconds, and the material is showing an annoying tendency to collapse. The team is therefore working with a process involving a porous mould, which will make it possible to use a vacuum to force all the water out of the paper. Thomas Howard estimates that the new process will enable the team to achieve the critical production time of six seconds.

At the same time, the bottle is being developed as a sustainable alternative to plastic bottles, and a life cycle analysis is to highlight the environmental benefits. In one context, the main advantage is blindingly obvious: if a bottle drops out of the deposit system—i.e. if it is thrown away in the countryside—then it will do no harm there. Because it is biodegradable. Other benefits have yet to be demonstrated, but the intention is for the new bottle to bring value back to the ecosystem, ideally through the collection and composting of the bottles.

So there are numerous parameters that have to align before beer in paper bottles appears on the shelves. But this is precisely the point and the charm of the project, as Thomas Howard explains:

“We have to live up to all sorts of requirements, as design and quality are also crucial in determining whether the bottle succeeds on the market. That is what makes this such a fascinating research project. It is rare for us to have the opportunity to develop a completely new product using a completely new material and a completely new production system. All in all, we’re in a situation where we need to have all our modelling designs gel perfectly to hit the ‘sweet spot’ where everything comes together in a coherent whole.”

Thomas Howard naturally hopes that he and his team will hit this point within the three years the project is scheduled to run: three years, which are also to determine whether the world is actually ready to drink beer from paper bottles. Thomas Howard himself is in no doubt:

“If everything goes according to plan, I’m sure we can make it. And I would love to be able to drink beer from a paper bottle three years from now.”

Innovation Fund Denmark has contributed DKK 15 million of funding to the project, which has a total budget of DKK 28 million.

Article in DTUavisen no. 3, March 2015.