Stora Enso Imatra Mills: Going With the Flow


Stora Enso is a giant in the renewable materials industry globally, producing close to 9 million metric tpy of paper and board. But it’s not just about quantity; the company produces some of the most intricate and technically challenging board products for the food and drinks industries, as well as for high-end luxury packaging.

The Imatra Mills are close to the Russian border in Eastern Finland, and on the day of our visit in February fresh snow had fallen in huge quantities. No matter for the production and logistics facilities here—snow and extreme cold are all part of everyday winter life, and the tons of pulp and high-quality board continue to be produced and delivered 24/7 no matter what goes on with the weather.

There are two Stora Enso fully integrated units within Imatra mills, Kaukopää and Tainionkoski, with a combined production of around 1.15 million metric tpy. The products produced here include liquid packaging board, food service board, graphical boards, and flexible packaging papers. Almost all production from the mills is exported, mainly to Europe, but also to Southeast and East Asia.

For the Kaukopää mill, Pesmel designed and delivered a bespoke solution using its TransRoll high bay storage rack concept.

Paper 360° visited the Kaukopää Mill, which is the world’s largest manufacturer of liquid packaging boards and is something of a showcase facility when it comes to the hygienic manufacture of specialist boards for food and drinks. There are three board machines running in the Kaukopää mill: BMs 1, 2, and 4, which produce cupstock, tray and liquid packaging board, graphic packaging, and cigarette boards, as well as liquid packaging boards. The mill also has 4 PE (polymer extruding) coating machines that provide the crucial element of barrier coatings to the board used for food and drinks packaging. The mill uses both polymer and a variety of biodegradable coatings on the PE coating machines.

The brownfield site at the Kaukopää Mill had seen numerous additions and expansions over the years, and the internal logistical demands for storing semi-finished goods for further coating or cutting were becoming a real problem. Mikko Nieminen, acting mill director at Kaukopää, says, “We always knew that we had to look at our internal logistics at some point. In 2016, the decision was made to install another PE coater, PE 6, and that meant it was the ideal time to find an all-encompassing solution to streamline both internal and external logistics.

“We were using a lot of external storage outside of the mill fence, and there were a lot of individual forklift and clamp movements going on, which could result in damage to the reels, no matter how careful our drivers and warehouse staff were,” Nieminin continues. “At the time, we employed around 30 people just to deal with the internal logistics.”

After a feasibility study and the usual due diligence process of reviewing major investments, in May, 2016, Stora Enso contracted Finnish pulp and paper logistics specialist Pesmel to provide a solution to the mill’s logistics bottleneck. The company, with its slogan Material Flow How, has been operating in and around the pulp and paper industry for 40 years and has delivered some 400 handling and packaging projects and around 120 storage systems. It also supplies logistics systems to the metals and tire industries, specializing in the storage and transportation of round, cylindrical, and flat products.

Pesmel designed and delivered a bespoke solution for the internal and external logistics at the Kaukopää Mill, using its TransRoll high bay storage rack concept. The 30,000-metric ton automated warehouse has eight connection points operating as both an intermediate buffer for rolls going to PE extrusion coating and also as a shipping roll buffer for finished customer rolls.

Tony Leikas, president and CEO of Pesmel, describes the system further. “The Imatra mill complex is very large and rolls need to be transported between various buildings. At Pesmel, we were able to provide innovative automative solutions to significantly improve the internal logistics at the mill. This was done with conveyor tunnels from production lines to the new high-bay storage and a special shuttle truck from the new storage facility to the existing mill units. Both the conveyors and the truck trailers were designed to maintain purity of board rolls.

“Also, previously, board rolls were kraft-wrapped when being moved to coating lines within the same mill complex, approximately one kilometer away— only to be unpacked again for the coating process. The intermediate wrapping phase naturally meant more work and higher costs.”

Ultimately, Pesmel’s delivery to the Kaukopää Mill at Imatra has helped eliminate many bottlenecks and has drastically reduced the need for manual roll handling. Clamp trucks have been replaced almost entirely by automated conveyor systems and Pesmel’s advanced warehouse management system ensures that storage and packaging operations are seamless and efficient.

Says Nieminen, “We chose Pesmel because, when we are looking at these investments, we are thinking ahead 20-30 years, and we needed a reliable supplier that can come with us on that journey.

“The new automated warehouse at the mill here has simplified what was a very complex logistics system,” he concludes. “There is now no more intermediate stock sitting outside the mill fence or in a manual warehouse; they are now in the black box of the automated warehouse, and we know exactly where every roll is. There is also no handling of the reels now, which reduces waste and damage. The new system has made a big difference in our production management, and has given us a lot more flexibility when it comes to managing the supply chain.”