Abstract: A method of and an apparatus for the scrubbing of waste gases and especially combustion gases by chemisorption. According to the invention combustion gases which can contain sulfur dioxide are scrubbed with water in the presence of lime and the scrubbing liquid is collected directly beneath the scrubbing column in an oxidation basin which is provided with means for introducing oxygen into the liquid to promote the formation of calcium sulfate crystals. The gases can sweep across the top of this basin and, at the outlet thereof, a coarse droplet separator is provided followed by a fine droplet separator or demister. Spray-water nozzles can be provided between the droplet separators for cleaning them.