Gas-Fired
Infrared Paper Drying
Why
Gas IR ?
According
to a Gas Research Institute (GRI - now GTI) Market Assessment, about
50% of the paper and paper board machines installed in the US and
Canada are drying limited. This prevents many paper
producers from increasing production on existing machines. The gas-fired
infrared burners can eliminate production bottlenecks and increase
productivity by more than 10% from the existing machines.
Efficient
and safe infrared burners offer a cost effective solution for increasing
the drying capacity. Installation costs are low compared
to other options such as adding more dryer cans at the dry end. The
gas infrared burners can be installed with little downtime.
Trials at the Herty Foundation
pilot paper machine have demonstrated production rate increases of
10 - 14%
Gas IR heaters produce
an infrared wavelength that is readily absorbed by
the water in the sheet. This leads to a higher temperature and a drying
efficiency increase that cannot be duplicated by conduction and convection
temperatures alone.
| Method |
Type
of Drying |
Drying
Rate
(lbs water/hr/ft2) |
| Steam Cans |
Conduction |
2 - 6 |
Air Hoods
Impingement |
Convection |
4 - 8 |
| Gas IR |
Radiation +
Convection |
30 + |
Gas IR
Options
Hot Pressing
- Apply heat before sheet
is pressed
- High Temperature reduces
water viscosity, improves dewatering, reduces drying load
- Improves moisture profile
- Reduction in steam requirements
and/or increase in drying capacity
Preheating
- Install IR between last
press and dryer inlet
- Heat sheet before it
enters dryer section
- Bring sheet to evaporation
temperature
- Allows higher surface
temperature in first few cylinders
- Excellent application
for drying limited machines
Supplemental Heating
along Dryer Section
- Install IR inside Dryer
Section
- Constant Evaporation
Zone or Falling Rate Zone
- Best location is machine
specific
More
Information
For more information about
the Gas IR Dryer advantage, see the various reports and papers located
in the Consortium Materials download section.
For specific Gas IR products, review the manufacturer's materials
in the Vendor's section. For more information
about how IR Dryers work, see IR
Dryers in the Learn About section.
