Abstract: Acidic gases such as sulfur oxides are removed from a waste gas stream by passing it through a reverse jet scrubber in which a suspension of finely divided limestone is used as an absorption medium. The method is particularly adaptable for use in a cement manufacturing plant wherein the sulfur dioxides in the waste gases from the combustion of fossil fuels used for process heat are removed by passing them through a reverse jet scrubber that uses as an absorption medium a suspension of finely divided limestone derived from the powdered limestone feed to the cement-making process and wherein the calcium sulfate slurry formed by reaction of the sulfur oxides with the calcium carbonate in the absorption medium is returned to the limestone comminution step of the cement making process and thereby disposed of as an ingredient of the cement clinker.