The subject of the present invention is an apparatus for the intermixing of a fluid stream with a fluid stream, which comprises a pipe through which the fluid stream is routed, at least two distributors for delivering the fluid stream being arranged inside the pipe, this arrangement of the distributors being made possible by bores in the casing of the pipe, and these distributors having a free flow cross section which is constant or decreases continuously, as seen in the main direction of flow of the fluid, and the distributors having one or more rows of holes for delivering the fluid into the fluid.