Stora Enso’s industrial site in Varkaus includes a board mill, a sawmill and a laminated veneer lumber plant. New packaging board is produced from both recovered packaging and virgin wood fibre. Photo: Stora Enso.

At Stora Enso’s mill in Varkaus, Finland, recovered cardboard packaging is converted into new fibre raw material. The same fibre can be recycled up to 7 times before it becomes too short and weak for further use.

The site contains Finland’s largest recycled-fibre processing facility. Covering approximately 3 hectares, it receives used packaging from households, retailers and packaging manufacturers.

More than 95 per cent of paperboard and cardboard packaging is recycled in Finland. However, domestic collections do not provide enough material for the mill, which also imports recovered packaging from Sweden and the Baltic countries.

Approximately 20 truckloads of recovered material arrive at the site each day. The compressed bales contain products such as milk cartons, pizza boxes and cereal packages.

Unwanted materials are removed
Metal wires are removed from the bales before the packaging enters a shredder. The material is broken into smaller pieces and mixed with water inside a rotating drum.

This mechanical treatment separates the fibres from the packaging. Plastic caps, aluminium layers, expanded polystyrene and other unwanted materials are removed from the pulp during the process.

Operators occasionally find unusual objects among the collected packaging. According to mill employees, even a leaf blower has passed through the shredder. Such incidents demonstrate the importance of sorting and continuously monitoring the process.

The recovered pulp is cleaned in several stages and pumped into storage towers before being transferred to the board machine.

– The material passes through several processing stages before the finished pulp is sent to the storage towers and used in the board machine, says Marko Laitinen, who is responsible for recycled-fibre sourcing at the mill.

Virgin fibre remains necessary
The board machine produces material measuring 7.8 metres in width. It is used as a surface layer in fruit boxes, food packaging and pizza boxes. A single finished reel can contain several tens of kilometres of board.

Most of the output is exported, primarily to Europe and Central America. The reels are mainly transported by road to the Port of Kotka and then shipped to international customers.

Production in Varkaus relies on both recycled and virgin wood fibre. According to Stora Enso, its containerboard contains slightly more virgin fibre than recycled material.

Virgin fibre is needed to maintain the strength of the board because fibres gradually become shorter and weaker during repeated recycling. Introducing new wood fibre therefore also supports the continued circulation of recovered material.

The industrial site uses approximately 2 million cubic metres of wood annually. Around 1.2 million cubic metres is used in board production, while 0.8 million cubic metres goes to the sawmill and laminated veneer lumber production.

Operating mill receives European recognition
The Varkaus industrial site received the European Heritage Label in spring 2026. Unlike many recognised industrial heritage sites, the complex remains in operation and continues to develop through modern board production and more efficient raw-material use.

The mill is located in the centre of Varkaus and is crossed by both a railway and Ahlströminkatu street. Because production continues around the clock, Stora Enso cannot receive all the individuals and groups wishing to visit the site.

The nearby Konsti Museum Centre instead presents the history of industry in Varkaus alongside information about present-day production.
  

Source: pulpapernews.com