The Swedish-Finnish paper and pulp company Stora Enso has launched Europe’s largest biocomposite production facility at the Hylte mill. The DuraSense product is a raw material with up to 80 percent less environmental impact than traditional plastics, where polymers or biopolymers combine with wooden fibre.

”The Stora Enso biocomposite is a new innovative raw material which helps create the desired properties in the products. The wood used in the bio-composite is obtained from side streams of wood products and pulp production, which means that the wood material is utilised optimally”, says Patricia Oddshammar, Head of Biocomposites in Stora Enso: ”Cost used to be an issue with biocopomposites, but we have been able to develop cost-efficient technology that makes the production competitive”.

The DuraSense wood fibre biocomposites are manufactured at the Hylte Bruk paper mill in Småland, Sweden, where the factory owner Stora Enso has invested 12 million euro in a new granulate production facility. Photo: Stora Enso.

Hylte Bruk has been one of the biggest paper mills in Sweden for a long time. As demand for newspaper has diminished, the forest industry group has been searching for opportunities to refine their renewable raw materials into new products and services in the growing bio economy. After conducting pilot experiments for a couple of years, the company decided in 2017 to invest 12 million euro in a new production facility – poised to be the largest of its kind in Europe. In June 2018, the facility was ready for opening.

”Affordable sustainability and the environment are climbing upwards on consumer agendas. DuraSense can reduce the consumption of plastic materials by up to 60 percent, ensuring less microplastics end up in the environment. Stora Enso’s biocomposites can be reused as a material up to seven times or recycled along with other plastic materials or, alternatively, used for energy recovery at their end of life”, Patricia Oddshammar says.

From pulp to granulate

The Hylte factory will have an annual production capacity of 15 000 tonnes. The process is fully integrated in the pulp production. Dried and pressed pulp from the mill is first mixed with polymers and additives in a compounding machine. The result is a granulate, which plastic producers can use as raw material in their existing moulding machines. The material offers the mouldability of plastic, but also the sustainability and workability of wood. The amount of wood fibre can be adjusted depending on the application at hand, and the product can be given different properties according to customer requirements. The main ingredient is Swedish spruce.

Environmental advantage step-by-step

DuraSense granulate is a combination of natural wood fibre, polymers and addititives, providing the mouldability of plastic and the sustainability and workability of wood. In the Gastro Max Bio product line, wood fibre is combined with  biopolymers made from sugarcane. Photo: Orthex Group.

The biocomposite is lighter than traditional plastic, and the fiber content is a direct replacement for fossil raw materials. But the environmental impact can be reduced even further, when the polymers which combine with the fibers in the composite are made from recycled or biobased sources. A new series of GastroMax products released by Orthex, a leading Nordic producer of household products, use sugarcane-based bioplastic in their DuraSense recipe. The products are manufactured in Kulltorp, Sweden:

”The properties of the new products made from wood-based materials correspond to those of similar plastic utensils: the products are hard, durable, hygienic and dishwasher-safe. The wood contained in the biocomposite makes the material stronger and harder. We are now launching nine GastroMax BIO products made of bio-based materials for the home kitchens. In their product group, products that contain 98 percent bio materials are uniquely innovative,” Orthex CEO Alexander Rosenlew says.

Stora Enso believes that composite materials is the natural first step towards fully replacing fossil-based plastics. The amount of fossil polymers will be gradually reduced as the technology ripens, the company predicts.

”Reducing the amount of plastic and replacing it with renewable and traceable materials is a gradual process. With DuraSense, we can offer customers a wood fibre-based alternative which improves sustainability performance and, depending on the product, significantly reduces the carbon footprint – all the way up to 80 percent,” says Jari Suominen, Head of Wood Products at Stora Enso.

Demand triggers follow-up investments

Since the product was met with positive response from the market, Stora Enso decided to increase their initial investment with 7 million euro. The investment covers a new Biocomposites Competence Centre and the installation of new machinery for the milling of large fibres for DuraSense. The competence centre will house a laboratory and piloting facilities, performance testing capabilities and a show room.

“At the new Biocomposites Competence Centre we will be able to share our knowledge with our customers as well as assist them with test runs and product testing, step by step“, Oddshammar says. “With the new equipment in place, Stora Enso will be able to provide more choice to DuraSense users in the technical properties and selection of fibres for the biocomposites, and also offer an attractive price position compared to traditional plastics. This will make it easier for customers to switch from existing material solutions to those based on biocomposites”.

Large fibre production is estimated to be up and running during 2019. In the future, certain end-user products such as planks may be manufactured on site, and the company hopes to eventually go from a single production line to seven or eight, employing many more than the current 20 workers in the process.

“With the help of biocomposites, Stora Enso can expand to new markets and industries traditionally dominated by plastics. The DuraSense bio-composite is the perfect material for furniture, pallets, tools and car furnishing as well as for various consumer products from toys, tooth brushes, beauty and lifestyle products to kitchen utensils, garden furniture and disposable cutlery”, Oddshammar concludes.

The article was published in August 2018.