New OptiDry Twin impingement drying solution from Metso

Published June 15, 2006 12.00.00 +2 GMT

A new impingement drying unit - OptiDry Twin - has been launched today at the Metso Paper Technology Days in Jyväskylä, Finland.

The OptiDry Twin impingement drying unit is a solution where the dry content, and the temperature, of paper is increased at the beginning of the dryer section while maintaining good quality and good runnability at the finishing sections. This prevents sticking, strengthens the web, and enables faster operation than without the OptiDry Twin unit.

The system consists of two drying units: a horizontal part and a vertical part, both equipped with blow boxes to hold the sheet on the fabric surface and lead rolls to support fabric and paper web travel. Thanks to the high evaporation rate of the system, a significant sheet dry content increase can be obtained on a high-speed machine.

Draw control without speed limits is the main target of OptiDry Twin. It only needs enough web tension for the web to stay attached to the dryer fabric on its way from supporting roll to supporting roll. There are no hot cylinder surfaces to which cold paper would attach. This creates excellent tools for optimal draw.

OptiDry Twin impingement drying unit brings the following benefits:

trouble-free tail threading excellent sheet runnability – sheet is held on the fabric surface with very moderate negative pressure significant potential for improved bulk – higher sheet dry content enables lower press loads shorter papermaking line compared to a conventional cylinder dryer section means shorter paper machine hall and lower investment costs improved efficiency shortens the investment payback time impressive drying capacity in rebuild cases provides noticeable speed increase

The OptiDry Twin drying unit is suitable for all paper and board grades, new machines or rebuild cases. It offers a viable option for improving machine efficiency, drying capacity and paper quality at a reasonable investment cost and short payback time.

For more information, please contact: Dr. Kari Juppi Manager, Product Development Paper & Board Business Line, Metso Paper Tel. +358 40 545 2397 E-mail: