Ranheim Paper & Board improves its PM6 approach flow system cleaning efficiency with Valmet´s cleaner plant
Ranheim Paper & Board, located just outside Trondheim, Norway, is deeply rooted in circular economy practices and has been using 100% recycled fiber since 1981. They are constantly improving and maintaining their processes and recently completed the installation of a Valmet Hydrocyclone Cleanpac 700 XCD cleaning system for their PM6 approach flow system for better cleaning efficiency.
Optimized plant design
The mill was facing the need to replace its existing cleaner plant, which had reached the end of its service life and for which spare parts were no longer available. A pre-study was carried out with Valmet´s experts to evaluate suitable cleaning solutions, resulting in the decision to install a Valmet Hydrocyclone Cleanpac 700 XCD plant designed to meet the mill’s operational requirements.
A key design criterion was the limited availability of dilution water. The new plant was designed to operate efficiently without dilution water, while retaining the flexibility for future integration if required. This future dilution capability enables the customer to adapt to any further needs to improve cleaning efficiency, reduce fiber losses, or increase production capacity.
In stage 1, the customer already used a flow meter to automatically control the valve. During the rebuild, an additional reject control valve was installed to automatically regulate reject flow, minimizing losses while ensuring low and even wear. The valve dynamically compensates for wear-related diameter changes, which would otherwise increase reject flow. This stabilizes performance and extends equipment lifetime.
The rebuild also made it possible to simplify the process with a smaller footprint, as the need for lightreject handling had already been eliminated. Removing the lightreject stage reduces overall system complexity and lowers energy consumption throughout the cleaner plant. With the 700 XCD cleaner plant, the cleaning efficiency has also increased.
The system was rebuilt to operate with continuous reject, which is particularly beneficial for OCC applications, where intermittent reject can lead to the buildup of fines and ash in the final stages. The simplified layout contributes to easy operation and maintenance, supporting stable production.
We are very satisfied with how the project was executed, from installation during our annual shutdown to start-up and the guarantee run. The collaboration worked smoothly, and the new installation has delivered the results we were aiming for,” says Andreas Volden, Ranheim Paper & Board.
Enhanced sustainability with Valmet Greenline material
To further strengthen their sustainability agenda, Ranheim Board & Paper selected the cleaners to be manufactured using Valmet Greenline material. This is a 100% renewable bioplastic material with equal wear resistance and chemical properties compared to Valmet cleaner parts from nylon-based plastics.
Since starting the operation, the cleaner plant has shown stable operation with no issues related to sand removal or overall cleaning efficiency. “We have seen improvements in white water thickening, with lower ash content across the system, which makes basis weight control easier. At the same time, the solution is simple to operate and easy to maintain,” Andreas Volden concludes.
