Metsä Fibre Selects ANDRITZ for Kemi Cooking Upgrade

Metsä Fibre has selected ANDRITZ to modernize the cooking system at its Kemi bioproduct mill in Finland. The upgrade is scheduled for start-up in the fourth quarter of 2026 and is intended to improve production flexibility, process efficiency and heat recovery within the mill’s pulp manufacturing operations.

The project focuses on upgrading the mill’s existing cooking plant to support both softwood and hardwood processing using continuous cooking technology. The modernization is designed to help the facility reach its planned annual production capacity of 1.5 million tons of pulp.

Continuous Cooking System Upgrade
The cooperation addresses operational requirements related to production flexibility and process stability in large-scale pulp manufacturing. Continuous cooking systems are used to chemically separate lignin from wood fibers during pulp production, and system configuration directly affects yield, energy efficiency and raw material utilization.

ANDRITZ will convert the existing cooking plant to its single-vessel LoSolids continuous cooking technology. The system is designed to improve liquor circulation and temperature distribution inside the digester, supporting more uniform cooking conditions and increased pulp yield.

The upgraded process configuration will allow the Kemi mill to process both hardwood and softwood feedstocks within the same production system, increasing operational adaptability based on raw material availability and market demand.

Equipment Scope and Technical Responsibilities
The modernization includes the installation of the ANDRITZ TurboFeed chip feeding system and a new Diamondback chip bin for improved chip handling and feed consistency into the digester process.

The scope also includes a vapor reboiler system intended to improve digester heat recovery. Recovered thermal energy can be reused within the production process, reducing steam demand and improving overall energy efficiency. The vapor reboiler is also designed to minimize odorous gas emissions generated during pulp cooking operations.

Metsä Fibre will integrate the upgraded systems into existing mill infrastructure and oversee operational implementation at the Kemi site.

Production and Industrial Impact
The upgraded cooking plant is expected to improve system availability, increase cooking yield and support higher production reliability. Improved raw material flexibility may also help optimize fiber sourcing and production planning across varying wood supply conditions.

The project continues the long-term cooperation between Metsä Fibre and ANDRITZ in industrial pulp production technology. ANDRITZ has previously supplied several major process systems, including the complete fiberline, for Metsä Fibre’s Äänekoski bioproduct mill.

The modernization reflects ongoing investment in industrial automation, energy-efficient processing and flexible production infrastructure within the pulp and paper sector.

Edited by Natania Lyngdoh, Induportals Editor, with AI assistance.

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