From the paper industry:
Exhaust gas systems in the paper industry
Design: The exhaust air systems in the paper industry are often burdened with water and paper residue.
Due to this problematic exhaust gas, all exhaust gas silencer are made without porous materials. The completely sealed and smooth stainless steel surfaces deliver adequate broad-spectrum noise reduction. Cleaning the exhaust gas silencer for acoustic reasons in no longer necessary.
Units: vacuum fans, rotary piston blowers, Roots blower, radial vents...
Example Nordland Papier, Dörpen
Example Technocell Papier, Osnabrück
Example Sappi, Austria
Example Leipa, Schrobenhausen