From the old clothes pile into the paper cycle
Under the leadership of Thomas Harter from the Institute for Biobased Products and Paper Technology, the project has a clear objective: to incorporate textile waste into the paper cycle instead of incinerating it or exporting it abroad. The approach is as simple as it is innovative: the mechanical processes from paper production are adapted so that textile fibres can also be processed.
First, the garments are cut into small shreds and soaked in water. The water-fibre mixture is then ground in a special grinder - a process that Master's student Alexander Wagner examined in detail in his thesis. He determined the ideal grinding time, the suitable device and the optimum ratio of water to textiles in order to obtain a fine, lump-free fibre suspension.
"In the end, we have a mass that hardly differs in appearance and behaviour from a classic paper suspension,"
explains Thomas Harter. The big advantage: the fibre solution produced in this way can be processed using existing paper manufacturing processes - a real benefit for the circular economy.
More strength, less waste: the potential of textile paper
Another plus point: the new paper is not only sustainable, but also particularly strong.
"Even with a textile content of 30 per cent, our paper is significantly stronger than conventional recycled paper,"
says Alexander Weissensteiner, who is also involved in the optimisation process. The reason for this is the longer fibres of the cotton: at around 1.7 millimetres, they are much more robust than those made from conventional recycled paper.
Visually, the textile paper is slightly brownish, with occasional splashes of colour - remnants of colourful items of clothing. However, this is not a problem for packaging such as cardboard boxes or envelopes. On the contrary: the visible origin emphasises the recycled character of the product.
Next step: from the lab to industry
However, the researchers' vision goes far beyond the laboratory. The next milestone is the energetic optimisation of the grinding process - for example through the use of enzymatic pre-treatment or mild chemical additives to break down the fibres more easily. At the same time, the team is planning to transfer the entire process to industrial plants.
"Strictly speaking, the conversion of textile fibres into paper is downcycling," admits Harter. "But in terms of the environment, it's a big win.
This is because the paper cycle is highly closed - over 80 per cent of packaging is recycled. If we put textile fibres in there, they remain usable for a long time."
#schongenial, how innovative Austria's researchers are!
