Abstract: The invention provides a process and installation for the treatment of a solid. The process includes passing the solid along a kiln having a hollow interior, while supporting the solid on supports moved successively along the kiln and heating the solid, by radiant heat, to a temperature at which it undergoes an endothermic chemical reaction. The installation includes a kiln having a hollow interior with an inlet end and an outlet end, a roof, a floor and a pair of opposed side walls, and a path for supports loaded with the solid to pass successively along in the interior, from the inlet end to the outlet end, the path extending along the floor. The installation includes heating surfaces for radiating heat towards the solid on supports passing along the path, and a plurality of supports, movable in succession along the path.