Ensuring recovery boiler reliability through proactive lifecycle services at Södra Cell Mörrum in Sweden
Image: Per Pixel Petersson / Södra
Recovery boilers are among the most important assets in a pulp mill, requiring continuous maintenance, timely upgrades and expert lifecycle support to ensure safe and reliable operation over decades of service. At Södra Cell Mörrum in Sweden, Valmet recently replaced a worn bottom furnace section during a scheduled annual shutdown, helping the mill maintain long-term recovery boiler reliability while enhancing corrosion resistance in a critical area of the furnace.
As a long-term service partner, Valmet was responsible for the project’s planning, delivery and installation, ensuring the work could be completed efficiently during the shutdown window and with minimal impact on mill operations.
Addressing wear before it affects operations
Like all recovery boiler components operating under demanding conditions, furnace floor structures are subject to gradual wear over time. During lifecycle assessments and maintenance planning, it was identified that part of the furnace floor had reached a stage where replacement would be beneficial to support continued reliable operation.
By carrying out the replacement during the annual shutdown, the mill was able to proactively address the condition of a critical component while avoiding additional downtime and ensuring readiness for future operation.
Combining proven design with enhanced materials
Valmet's delivery included the manufacturing and installation of six new furnace floor panels comprising a total of 128 tubes. The replacement panels were designed to integrate seamlessly with the existing boiler while incorporating a targeted material upgrade in one of the most demanding operating areas.
As part of Valmet's lifecycle commitment, critical connection areas were upgraded with Sanicro® 38 material. The enhanced corrosion resistance helps protect the recovery boiler against wear mechanisms common in lower furnace environments, supporting long-term reliability and extending the lifetime of key components. The remaining sections were manufactured according to the existing boiler design specifications using carbon steel.
This combination enabled the customer to maintain the proven design of the recovery boiler while improving durability in a critical area exposed to challenging operating conditions.
The recovery boiler is a critical asset for our mill, and maintaining its long-term reliability is an important priority. The furnace floor replacement was completed smoothly during our annual outage, and the material upgrade provides enhanced corrosion resistance in a demanding operating area. Valmet's knowledge of our boiler and its support throughout the project contributed to a successful outcome,
Smooth execution during the annual shutdown
The replacement work was completed during the mill's scheduled annual shutdown. Careful planning, coordination, and execution contributed to a successful project outcome, allowing the installation to proceed smoothly within the shutdown schedule.
"Recovery boilers require continuous lifecycle attention to maintain safe and reliable operation. Through planned maintenance, targeted upgrades, and outage support, we help our customers maximize the value of their assets throughout their entire lifecycle. The Mörrum project is a good example of how proactive replacement of critical components can support long-term reliability while being executed efficiently during a scheduled shutdown," comments Michael Ryding, Project Manager, at Valmet.
Supporting long-term reliability
The project targeted at ensuring long-term reliability and maintainability of a critical process asset. Following the replacement, boiler operation remained stable while the upgraded material provides improved corrosion resistance in the connection area to the back wall.
The project demonstrates how proactive lifecycle services, planned maintenance, and targeted upgrades can help pulp producers maximize the value of existing assets while supporting safe and reliable operation throughout the recovery boiler lifecycle.
About Södra Cell Mörrum
Södra Cell Mörrum is one of Södra's specialized pulp mills located in southern Sweden. The mill operates two production lines, producing both premium paper pulp and dissolving pulp for textile and other industrial applications. With an annual production capacity of approximately 470,000 tonnes of pulp and around 400 employees on site, the mill plays an important role in Södra's operations and is recognized for its focus on safety, innovation and reducing climate impact.
