a scrubber for exhaust gases comprises a series of nested counter - flow passages including a hot plenum having a star - shaped section . exhaust gases from the hot plenum surge through a liquid bath and flow in a reverse direction through an inclined array of flat , overlapping , spaced mixing vanes , causing turbulence in the exhaust gases and the formation of highly dispersed tiny bubbles , which enhance the solution of gaseous pollutants into the scrubbing liquid . mist eliminator vanes strip entrained liquids from the exhaust gases . the hot plenum , reheats the exhaust gases to an unsaturated level . the scrubber is highly effective in reducing particulate matter , stripping sulphur dioxide and nitrogen dioxide from exhaust gases , and reducing the heat signature and visual evidence thereof .