Process control system modernisation for Stora Enso's Skutskär mill in Sweden
The project was to replace the old supervision and control interface of the recovery boiler 7.
Continuous improvement work is underway at Stora Enso's Skutskär Mill in Sweden. Skutskär Mill produces pulp for many of the products we use in our everyday life, such as napkins, various hygiene products, diapers, and nonwoven materials. This means that if Skutskär Mill ceases production, many people will be affected. Therefore, it is extremely important that the heart of the factory, the recovery boiler, remains up and running 24/7.
Stora Enso Skutskär Mill’s recovery boiler 7 was originally commissioned in 1976. During the 40 years since, relevant technology has undergone considerable progress. That progress is the reason why Skutskär Mill decided to implement several modernisation projects and find more sustainable solutions for the future. One of the modernisation projects was to replace the old supervision and control interface of the recovery boiler 7.
The project was started in 2018, and AFRY was assigned as the main engineering partner. AFRY was given the responsibilities of process control system engineering, procurement, and construction management services (EPCM). AFRY delivered the project ahead of schedule.
“Being up and running ahead of schedule obviously means a lot to us,”says Henrik Holm, Director Manager at Skutskär Mill. “Overall, the entire project was carried out very professionally. There were no interruptions or unforeseen events during the implementation at all, which we link to AFRYs meticulous planning and good cooperation between all project parties”.
Holm also states that the commissioning process was very smooth and emphasises the importance of that process.
“Since recovery boiler 7 is directly connected to two of our three lines, a delay at start-up would have meant financial loss for us, but in this case we saw early that it will not be the case,” says Henrik Holm, highlighting the extent of AFRY’s competencies and long experience in implementing complex modernisation projects like this.
Skutskär Mill holds several values which play a role when selecting a partner in a complex project.
"AFRY’s understanding and valuable knowledge of the process technologies and their ability to link modern tools and methods have contributed to an improved efficiency and reliability overall," says Holm.
Upgrade or invest?
AFRY was involved in the recovery boiler project from the feasibility study onwards and was also responsible for developing all the technical documentation together with Skutskär’s project manager.
“Recovery boiler 7 had a traditional control system, and there was a need to modernise its process control. The study project demonstrated how the recovery boiler would ’shake hands’ with the modern technology we have today. At the same time, the focus at Skutskär Mill was to further increase safety, both for people and machinery at the mill,” says Ulf Andersson, Project Manager at AFRY.
Ultimately, it was decided that investing in a new process control system would be the best option concerning the mill's future. The challenge that both parties faced was that the new system had to be implemented within 8 months.
The right person in the right place
Although AFRY has valuable experience in handling similar projects, this project came with its own unique challenges.
“We decided to carry out some parts of the project in a different way than before,” says Ulf Andersson. “With such a tight schedule, we saw the importance of a resource that could act as a link between the control system provider (ABB) and the process, which was a dedicated person with experience. At AFRY, we have a broad field of experienced consultants, which is required to handle such assignments. In this case, one of our project engineers was a valuable team player”.
“Our strength lies in our ability to adapt to the needs of our partners,” says Max Allemo, Section Manager at AFRY and responsible for the composition of the recovery boiler 7 project team.
“In this case, I am extremely grateful for all these experts we have within AFRY and for our project tools, which help us to support our customers locally in the best way,” explains Allemo.
During the project, AFRY contributed with around 10 engineers during the design phase, and during the commissioning phase, more resources were added. In collaboration with the customer and other suppliers, the team succeeded in commissioning 14 hours before the scheduled cut-off. 14 hours might not sound like much, but it is very meaningful to Skutskär’s operations. Skutskär Mill will see major changes with the new solution in place.
“Today we have a much safer mill than before and the possibility to monitor operations in a new way. Our ability to change and develop production is also completely changed. We are very pleased with our cooperation and the end result,” concludes Henrik Holm.