Abstract: An apparatus for gasifying coal dust has a housing provided with an output fitting for the removal of generator gas and an output fitting for the removal of granulated slag. An overflow maintains a body of liquid in the bottom of the housing and a coal-dust burner in the housing forms a downwardly moving coal-dust flame in an upper reaction zone of the housing. An annular tube wall in the housing upper and lower ends where its tubes are bent apart and form radially throughgoing upper and lower openings and at the burner and therebelow but above the generator-gas output fitting. This tube wall is radially gastight between its upper and lower openings and radially inwardly delimits an axially extending annular passage that is outwardly defined by the housing. Steam is fed to the upwardly directed lances in the passage to create in the housing a toroidal annular current of moving gas and steam rising in the passage and descending in the zones between the flame and the tube wall.