New processes yield more products from forest residues

The development could give the forestry industry new saleable products in the form of nanofilters that can clean gases, industrial water and drinking water.

‘There is large interest in this from industries, especially because our bio-nanofilters are expected to be of great importance for the purification of water all around the globe,’ said Aji Mathew, associate Professor at Luleå University of Technology, who led the EU-funded NanoSelect project.

On August 27, 2013, the researchers demonstrated to industry and researchers how they scaled up nanocellulose manufacturing processes from two different residues obtained from forest based industries.

The first was cellulose from Örnsköldsvik-based Domsjö Fabriker, which came in the in the form of a fibre residue that is ground down to tiny nanofibres in a grinding machine. Through this process, the researchers have managed to increase the amount of cellulose nanofibre, processing from 2kg per day to 15kg per day.

Another byproduct, cellulose nanocrysals, has been successfully scaled up from 50gms/week to 640gms/day using a bioethanol pilot plant at SEKAB in Ornskoldsvik. According to a statement, both processes can be scaled up.

‘If everything goes well, we could add value to our waste through this technology. Currently, we earn almost no money on it and as there is almost no space to store it we give it away,’ said Anna Svedberg, product engineer at biorefinery Domsjö Fabriker AB.

Björn Alriksson, an R&D engineer at research and testing company SP Processum, also sees opportunities in finding new products from forest resources through this research.  

‘It is very relevant in the current situation because the paper industry is not good as in the past. There is a declining market, especially for newsprint and the need to find new products from the forest and therefore nanocellulose is a very interesting new product,’ he said.

Nanofilters for purification of industrial water and drinking water are one possible product made possible by nanocellulose.

However, large-scale production of nanocellulose is necessary to meet a growing interest to use bio-based nanoparticles in a variety of products, said Prof Kristiina Oksman , Luleå University of Technology.