Impingement drying is a very efficient way of drying the paper web. The drying medium is air. Effective drying is gained by blowing hot, high-velocity air onto the sheet and circulating the air back to the dryer. This method yields a considerably higher specific evaporation rate than conventional cylinder drying thus enabling shorter paper and board machines and machine rooms. The drying air is heated with gas providing flexibility for drying energy concepts.
OptiDry impingement drying technology has been developed both to replace and to improve traditional cylinder drying technology. It is the most effective way to dry paper. We have three impingement drying solutions offering different benefits for papermakers.
The revolutionary OptiDry Twin represents impingement drying technology that provides superior drying efficiency. Resulting in excellent runnability, enhanced draw control and increased bulk. OptiDry Vertical is the rebuild dryer increasing drying capacity without adding machine length. It is placed under the existing dryer section with minimal changes to current layout. OptiDry Curl offers energy efficient curl control for single felted dryer sections.
One example of the superior qualities of OptiDry impingement dryers is Zhanjiang Chenming PM 1 in China with OptiDry Twin and OptiDry Curl impingement dryers and world record speed.
Valmet impingement drying offers an advanced and sophisticated way to increase machine production, efficiency and end product quality, in an energy-efficient way, on both new and rebuilt paper or board machines.
On September 1, 2011, the world's largest and fastest woodfree-producing paper machine was started-up at the Zhanjiang Chenming mill in China. During its first operational year, it achieved on several occasions a new world speed record. In November 2012, the recorded speed was 1,808 m/min. During a 24-hour run, the 11.15-meter-wide PM 1 produced high quality printing paper at a basis weight of 70 g/m2.