PURPOSE: To provide as one body a sludge supply pipe and air supply pipe and providing a cooling medium flow channel in the inside of a burner and exposing the tip end of the burner on the side wall in a furnace.

CONSTITUTION: A sludge burner 6 is installed to be exposed on the side wall 20 of the rotating melting section of a sludge melting furnace 2. An inner cylinder 61 is provided at the center of a cylindrical main body 60 and an outer cylinder 62 encircles the inner cylinder 61. The inner cylinder 61 supplies sludge Wi, and the outer cylinder 62 feeds swirling air Ar and is connected to a rotating flow swirler, and in the inside of the main body 60 cooling water Wc which cools the inner wall 61, swirler, and the outer wall of the main body 60 is supplied. With this constitution the slag flowing down the inner face of the side wall 20 is cooled by the sludge burner 6 and forms in the initial stage a cooling layer S which excels in heat insulation for the exposed face. The slag (s) that flows down after this flows down along the exposed face of the sludge burner 6 to prevent a burning of the sludge burner 6 and closing that accompanies solidification of the slag (s) does not develop.