Abstract: A venturi scrubbing system optimized for removing the most optically active sized particles from a gaseous effluent stream is disclosed. Before entering the venturi the effluent stream is subcooled to cause condensation of water vapor and other condensibles, thereby greatly reducing the volume of the effluent stream. In the venturi stage a scrubbing liquid is added in the form of droplets having a median diameter which is optimized to remove the optically active particles. Preferably, the median diameter of the scrubbing liquid droplets is between 10 and 200 microns. A two-fluid nozzle may be used to efficiently form the droplets. After passing through the scrubbing stage, which may also comprise one or more impingement plates, the cleansed effluent may be passed through an afterburner to remove combustible materials such as organic vapors.