How paper should become more environmentally friendly

It's one of those things that everyone needs on a daily basis: toilet paper. Every German gets 12 kilograms or 134 rolls of it a year. In addition, there are handkerchiefs, coffee mugs, parcels - that's 250 kilograms of paper per capita and year. But the production of cellulose, the basic material for paper production, is considered to be extremely energy- and water-intensive. Some of the material is recycled. But since last year, the industry has been complaining about a lack of supplies. Researchers and companies are therefore looking for new processes to produce fresh fibers as environmentally friendly as possible.

The Finnish company Metsä Tissue, one of the largest manufacturers of tissue paper in Europe, has now developed a new way of doing just that in a cellulose mill in southern Finland. Scientists at the Fraunhofer Institute for Microstructure of Materials and Systems in Halle have now checked what is true of the promise.

In a so-called life cycle analysis, they compared the environmental balance of three conventional processes with the new cellulose production based on various factors and found that the Finnish process actually performs significantly better in some areas. It was shown that the new method uses up to 45 percent less greenhouse gases and 70 percent less fine dust and is only about half effective compared to the TCF process, which does not use chlorine compounds for bleaching and was therefore previously considered to be relatively environmentally friendly so damaging to the ozone layer.

Sven Wüstenhagen, head of the study, explains: "The process uses the heat generated and the waste products more efficiently than previous processes." For example, the lignin that is produced during the manufacture and bleaching of the cellulose is burned in such a way that the energy released is channeled back into the process . In addition, the chemicals used would be less ozone-depleting.

According to Wüstenhagen, however, it is still unclear what the effects of the new process will be on biological diversity. The Finns used wood from coniferous forests as the starting material, while one of the other methods used eucalyptus from the tropics, for example. Wüstenhagen says: "You have to take a close look at the balance sheet again."

Despite this, Wüstenhagen sees great potential in the new “bioprocess”. Similar to how wind turbines are retrofitted and built higher to generate more energy, existing cellulose plants can be converted to greener versions. "It's a question of cost," he says. But it is always worth it for the environment.

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