Receive 5-15 % energy savings with effective pocket ventilation

Significant energy saving is guaranteed with an EVpv Pocket Ventilation™ system, by decreasing the pocket humidity level, correcting the pocket moisture profile and eliminating the need for over-drying. 


The PM drying section is a major steam consumer: over 75 % of paper machine steam consumption is used in the drying process. High pocket humidity level, uneven sheet moisture profile and runnability problems are the results of poor pocket ventilation.

Typical problems with poor or unventilated dryer cylinder pockets:

  • Increased steam consumption
  • Uneven CD moisture profile in cylinder pockets → uneven sheet moisture profile → over-drying → ENERGY LOSS
  • Decreased production

 

The EVpv pocket ventilators are installed near the felt rolls blowing dry supply air to the pockets. This decreases the pocket humidity level, corrects pocket moisture profiles and eliminates the corrective over-drying. Over-drying of edges is controlled by adjustable edge blowing nozzles.
 

Benefits:

  • Improved runnability
  • Lower drying costs
  • Increased speed potential
  • Fewer web breaks
  • Better moisture 2-sigma
  • Increased production

 

Reference:

SC, sheet width at reel 540 cm

  • Steam consumption: 33 t/h to 30 t/h
  • Speed: 1025 m/min to 1065 m/min
  • Production: 19.6 t/h to 20.6 t/h