Long-term collaboration and repeat orders result in win-win for both partners

Holmen Iggesund’s mill in Iggesund, Sweden, has a long and fascinating history. With its origins dating back to 1685, today it is one of the world’s most advanced fully integrated pulp and board mills.

The mill operates two fiberlines for the production of bleached softwood and hardwood pulp, a board mill comprising two board machines, and a drying machine for producing bale pulp. Of course, with such a long history, both the mill and process equipment have undergone numerous modernizations and rebuilds.

Holmen Iggesund and Valmet have long enjoyed very close collaboration, which started around twenty years ago when an upgrade for the mill’s hardwood fiberline was needed. They chose Valmet to supply a new screen room, based on DeltaScreens, and a new brown stock pulp washer consisting of two model TRPA-940 TwinRoll presses.

The successful collaboration has continued ever since, with Valmet supplying upgrades and additional wash presses over the past two decades.

One order leads to another

The first upgrade in 2004 was made because some of the older equipment on the hardwood line had begun to reach the end of its life. Time had taken its toll on both the older operational control systems and the filter presses, which dated back to the 1970s and 1980s. Holmen Iggesund took the opportunity to invest in a wash-press-based bleach plant instead of filter presses on the rebuilt hardwood line.

"Valmet’s wash presses really do help reduce electricity and water consumption,” says Hägglund.

Peder Hägglund, Technology, Projects and IT department manager at Holmen Iggesund, explains the company’s approach to equipment selection and long-term partnerships. “When selecting a supplier for wash presses, for example, we consider experience, quality, process expertise, and – of course – the price. We’d been very pleased with Valmet going back many years, so we’ve decided to work with them again every time. We prioritize long-term collaboration and partnerships with our suppliers, aiming to make it a win-win situation for us both. Interchangeability is also important, and we value the fact that we can use common spare parts for the various machines. And we only need to train the operators to work on a few pulp washing machines, which is a big advantage,” says Hägglund.

It’s easy to pick up the phone and get hold of competent and talented people from Valmet. That’s extremely valuable.

Sustainability is another important topic, and the TwinRoll wash presses’ high efficiency provides benefits here as well. Hägglund says that Holmen Iggesund’s own customers are much more environmentally aware about the products they are buying today. “It’s very important that the technology and machinery we invest in meet our own and our customers’ expectations of a reduced environmental impact. And it’s clear now that Valmet’s wash presses really do help reduce electricity and water consumption.”

Water consumption cut by almost 50 percent

Mattias Brink, Project Manager at Holmen Iggesund, says that the current TwinRoll press investments and wash press upgrades on the hardwood fiberline in 2023–24 will help make the plant more modern and efficient. Water consumption is a major issue. “Because of the new wash presses, we expect to drain off about 100 cubic meters per hour less. That’s the big benefit at the bleach plant, where we expect to cut water consumption by almost 50 percent and to maintain high quality at the same time,” he says.

Another important aspect of the hardwood fiberline rebuild is that it now runs with an increased automation level due to the implementation of a more modern control system. This allows better and tighter control of many more variables, supporting the mill’s efforts to close loops in the bleach plant and save even more water.

Brink also says that previous projects with Valmet have been successful and have generally passed all the warranty checks quickly. “The start-up for their latest project, where the D0 filter was replaced with a TwinRoll press in stage 1, was really good, and the performance tests were done shortly after start-up.”

From left: Peder Hägglund and Mattias Brink outside the Holmen Iggesund mill.

Successful stepwise replacement of presses with the mill running

Initially, the idea was to do just one big project and replace all the old filters with wash presses at the same time. But then Holmen Iggesund decided a better strategy would be to carry out the project work in stages instead. This proved to work very well in terms of layout, making it possible to remove an old filter to free up space and to prepare for the new washer’s installation without any hassle while the plant was still up and running.

“Doing things this way worked well, given that we could then prepare each step while the plant was running, instead of going for a major shutdown with the pressure of having to do everything all at once. Doing the job in this stepwise manner has worked really well,” comments Hägglund.

Working to close water loops

The next big project will be the start-up of two new wash presses during the shutdown in the fall of 2024. The infrastructure and control system have already been put in place during the first phase, which will simplify the project, with the second stage focusing more on the actual machinery.

“We’ve deployed this type of wash press before, so it’s nothing new to us,” says Hägglund.

“The challenge we now face involves closing the water loops in the mill – and how tightly to close them. This is something we need to test as we go, and we think it would be a good idea to hook up with Valmet to work out how best to proceed. The aim is to take a ‘smart and cautious’ approach and minimize water consumption as much as possible. As very large volumes of water are being circulated, it could take up to six months for all the effects to be seen.”

Close cooperation pays dividends

The close cooperation is continuing, and Holmen Iggesund is now looking forward to installing and assembling the last wash presses for the bleach plant. “Then we will introduce a spare parts approach and start monitoring the process across the line,” says Brink.

Valmet can get to the Iggesund mill in just over an hour, which provides highly appreciated flexibility. “We’ve enjoyed a good relationship with Valmet over the years and have always received support when needed. It’s been easy to pick up the phone and get hold of competent and talented people. That’s extremely valuable,” concludes Hägglund. 

Text Elin Boström Photos Henrik Högberg