PetroStreet

I know that mesh pad type mist extractor is generally less expensive than the vane type but in which conditions, vane type is the one which in anyway is needed as per process design?

The core difference here is that mesh pad captures droplets by impaction + coalescence however, vane type forces gas to change direction, droplets slam into plates and drain.
Mesh = delicate but efficient for small droplets
Vane = tougher, handles dirty, aggressive flow