Energy-efficient coating drying for Metsä Board rebuilds

May 27, 2013

“We had previous experience with Valmet’s air drying technology and the new PowerFloat nozzle design, so we trusted the energy saving calculations and decided to choose PowerDry Plus dryers for our machine. All the guarantees on energy savings, drying capacity and runnability have been fulfilled. We are happy to work with Valmet,” says Raimo Salmi, Technical Manager of Metsä Board's Kyro mill.

Metsä Board has increased its cartonboard capacity by 150,000 tpa to 935,000 tpa with investments made at three cartonboard mills in Finland. The Metsä Board Simpele rebuild was completed in June 2011, Kyro in November 2011 and Äänekoski in May 2012. At the Kemi linerboard mill, production was refocused to coated grades after an investment made in 2011. This has been a success and Metsä Board's state-of-the-art paperboard capacity, including the Kemi mill, today totals 1.31 million tpa.

The Simpele mill was the first mill to introduce high intensity air drying technology in its earlier rebuild in 2006, and now, after the new rebuilds, the PowerDry Plus technology is also successfully in use at the Kyro and Kemi mills.

In the Metsä Board Kyro BM 1 rebuild, a PowerDry Plus air dryer was selected to replace the gas IR dryer in coating station 1. A PowerDry Plus air dryer was also chosen for the coating drying for a new coating station 3. Replacement of the infrared dryer at coating station 1 will provide annual energy savings of 4,800 MWh, as well as excellent drying capacity, runnability and end product quality.

Air drying brings energy savings

PowerDry Plus is a one-sided air dryer for all paper and board grades, for new machines as well as rebuilds, enabling over 50% energy savings compared with infrared dryers. PowerDry Plus has been developed to replace IR dryers in the drying of coated paper, providing improvement in energy efficiency, evaporation capacity and in end product quality.

Valmet´s famous air dryers PowerDry and TurnDry are now available under the renewed OptiDry air drying family.