Louver damper

Basic data:

Plant:  FGD and DeNOx plants
Country: Austria
Investor: ABB – Umwelttechnik, Butzbach
Dimensions: 10000 x 9000 mm

Louver damper
Louver damper


Raumag Janich received an order for the design and supply of all flue gas shut-off and modulating dampers required for the FGD and DeNOx plants of the Theiss 2000 powerstation. Among that was  the shut – off damper for the DeNOx reactor. The damper should work in high temperatures without distortion. Moreover, the solution should take as little space as possible.


We designed a louver damper with the patented, lattice supported, single shell damper blades.


We reduced the loss of free area from 25% value for conventional dampers to as low as 7%. The “floating” attachment of the blade shell to the lattice support structure facilitates its free expansion and thus averts any distortion. At the same time all members of the support structure are heated up very evenly by the flue gas which can flow right through it nearly unrestricted so that distortion is once again precluded.