Metsä Group Punkaharju mill reduces dust emissions with an Electrostatic Precipitator upgrade

Metsä Group’s Punkaharju mill produces Kerto LVL products and plywood and employs around 500 people. Picture: Metsä Group

The 32 MW power boiler at the Punkaharju mill originally started up in 2002. The boiler was equipped with a two-field electrostatic precipitator (ESP), a cost-effective and energy-efficient solution for removing dust particles from flue gases. The power boiler produces steam needed in production, and its reliability ensures stable operation of the entire mill.

Metsä Group and Valmet’s cooperation at the Punkaharju mill started in 2023, when Valmet performed the power boiler’s mechanical and electrical inspections during the mill’s annual maintenance shutdown, prior to the planned ESP upgrade.

The upgrade was a good opportunity for us to secure the performance of our ESP for now, but also as preparation for tightening emission regulation in the future. We were happy to utilize Valmet’s expertise in the project,” says Sami Puronaho, Powerplant Manager at Metsä Group Punkaharju mill.

Full-scope delivery for improved ESP performance

Valmet’s delivery included the manufacturing and installation of all internal components of the existing ESP such as collecting plates, emission electrodes, insulators, rapping system including drives, and computational fluid dynamics modeling (CFD). Valmet also supported the customer in the start-up of the refurbished ESP.

“Overall, the delivery and commissioning went smoothly and as scheduled. Thanks to the good cooperation and easy communication, any obstacles along the way were overcome professionally,” Puronaho says.

“ESP performance were able to deliver results that exceeded expectations, which I’m of course proud of,” says Lari Turunen, Project Manager at Valmet.