In this device the air passes through two counter flowing sprays directed at a mesh grid. The main advantage is that it can fit inconspicuously onto a flat roof.

In all wet scrubbers a demister is used to remove the entrained water droplets.

OR IN THE FORM OF A LOW PRESSURE DROP VENTURI SCRUBBER.
NOTE THE CO-FLOW GEOMETRY

The systems shown above rely, for their particle collection ability for the collision of particles with droplets of the wash fluid. Other systems rely on interaction between the particles and either thin films or bulk pools of liquids. This process is often called impingement.