Compact’s range of short wave infrared dryers is used to improve the product quality of paper and board in two main areas, CD and ‘Z’ direction moisture profile control and coating drying.
CD MOISTURE PROFILE CONTROL
The drying rate across the full machine width is not always as uniform as either the paper maker or their customer would like and Compact Engineering make a range of dryers that …….
- Flatten the moisture profile to give uniform product quality,
- Provide excellent reel building
- Improve converting rates from parent reels.
The dryers from Compact Engineering are normally run in a fully automatic setting, taking live and unfiltered data from the existing quality control system and using this data to flex the drying rate across the machine width.
Typical improvements:
- CD moisture variation of 3.5% reduced to ~0.3%
- ‘Z’ direction spread reduced by 90%
- Including ~10% production increase
Compact infrared will dry the wetter parts of the sheet and allow the paper machine productivity to be set by the most effective parts of the dryer section rather than the least productive.
Using Compact infrared to flatten the CD moisture profile brings water from the middle of the sheet to the surface so that it can evaporate. This action re-hydrates the surface fibres making them more flexible so they are more easily smoothed at the calenders, which in turn gives better smoothness while retaining the bulk in the sheet.
Correcting the CD moisture profile will also correct the sheet calliper where the calliper spread is not derived from poor sheet formation.
CD MOISTURE PROFILE CONTROL
The drying rate across the full machine width is not always as uniform as either the paper maker or their customer would like and Compact Engineering make a range of dryers that …….
- Flatten the moisture profile to give uniform product quality,
- Provide excellent reel building
- Improve converting rates from parent reels.
The dryers from Compact Engineering are normally run in a fully automatic setting, taking live and unfiltered data from the existing quality control system and using this data to flex the drying rate across the machine width.
Typical improvements:
- CD moisture variation of 3.5% reduced to ~0.3%
- ‘Z’ direction spread reduced by 90%
- Including ~10% production increase
Compact infrared will dry the wetter parts of the sheet and allow the paper machine productivity to be set by the most effective parts of the dryer section rather than the least productive.
Using Compact infrared to flatten the CD moisture profile brings water from the middle of the sheet to the surface so that it can evaporate. This action re-hydrates the surface fibres making them more flexible so they are more easily smoothed at the calenders, which in turn gives better smoothness while retaining the bulk in the sheet.
Correcting the CD moisture profile will also correct the sheet calliper where the calliper spread is not derived from poor sheet formation.
COATING DRYING
Compact design and manufacture their own shortwave lamps, which allows them to design systems with the necessary energy density at the right wavelength to optimise the coating drying process. The benefits of this are that:
- The infrared penetrates the coating and heats the sheet below.
- Creates a positive vapour pressure, which causes controlled evaporation.
- The coating is dried from the sheet/coat interface outwards guaranteeing perfect results consistently.
Compact’s active boundary layer management system ensures maximum moisture removal for minimum kilowatt consumption and keeps the coated surface cool.
Compact’s dryers give complete control over binder migration resulting in:-
- Coated surface with even distribution of the pigments and binders in the coating which is free from mottle.
- A cool surface ensuring no orange peel effect brought about by surface over heating.
- Consistent porosity values.
Apollo Coating Dryer
