A cooled grate block as part of a grate for a system for thermally treating waste, including: a block body in the form of a cast part having an outer supporting face for the waste to be treated; a flat cavity situated directly below the supporting face, for receiving a cooling fluid; a fluid feed line and a fluid discharge line, which are connected to the cavity; at least one deflection element, which is arranged in the cavity to direct a cooling fluid within the cavity from the fluid feed line to the fluid discharge line; and a valve element situated in the end region of the cavity, for distributing the cooling fluid fed into the cavity through the fluid feed line.

A cooled grate block as part of a grate for a system for thermally treating waste, including: a block body in the form of a cast part having an outer supporting face for the waste to be treated; a flat cavity situated directly below the supporting face, for receiving a cooling fluid; a fluid feed line and a fluid discharge line, which are connected to the cavity; at least one deflection element, which is arranged in the cavity to direct a cooling fluid within the cavity from the fluid feed line to the fluid discharge line; and a valve element situated in the end region of the cavity, for distributing the cooling fluid fed into the cavity through the fluid feed line.