Wasteair-dedusting, Energy-Spraytunnel, energy-efficient application

Fercher - technology in use in a paper mill in Germany.

Exhaust air heat exchanger spray tunnel wet scrubbing

In addition to energy recovery from the exhaust air, the objective was to significantly reduce the odor problem caused by the exhaust air.

The exhaust air from a paper machine is collected on the factory roof at the existing exhaust air chimneys and passed through a Fercher exhaust air heat exchanger type EST (Energy Spray Tunnel) with a diameter of 3 meters.

After the exhaust air has been sprayed, it exits the spray tunnel washed and cooled.



Circulating water, waste heat, exhaust air

As the exhaust air cools, any water vapor it contains also condenses.

This condensate creates a "spray water surplus."

This condensate can be used in a variety of ways, such as being fed back into the system as process water.


A droplet separator at the end of the spray tunnel ensures that no water is wasted. The separated water flows out along with the spray water in the spray tunnel and is thus returned to the spray water circuit.

"Odor reduction of the exhaust air and massive energy savings with a short payback period."