Abstract: A process and an apparatus for mechanically removing a sulphur containing layer from lumped lime, wherein the lumped lime is accelerated from a bottom member by a mechanical impulse and projected from the bottom member against a processing surface having profiles provided over partial sections thereof to remove the sulphur containing layer, when the lumped lime returns to the bottom member and the process is repeated along a conveying path for the lumped lime for a determined length of time, or for as long as it takes to achieve the desired removal of the sulphur containing layer.