NOVELTY - The device comprises a connected gas cooling chamber, a tapered connecting channel (5) running from one chamber to the other, and eddy reducing or eliminating wall surfaces (6) running over only a part of the cross-section of the connecting channel provided in the tapered connecting channel. The wall surfaces are formed by cooling tubes, and have a structure slightly twisted in a longitudinal direction. A cooling groove that collects the slag at a lower end of the wall surfaces in the direction of gravity is provided for releasing the slag from a quenching chamber.    USE - Device for producing a crude gas containing carbon monoxide or hydrogen by gasification of an ash-containing fuel with oxygen-containing gas at temperatures above a fusion temperature of the ash in a gasification reactor.    ADVANTAGE - The device economically avoids and reduces the amount of fly ash and ungasified fuel with less effort, achieves a weak eddy in the inlet to the subsequent apparatuses thus avoiding deposits, and avoids the risk of solidification of the slag in the outlet.    DETAILED DESCRIPTION - The device comprises a connected gas cooling chamber, a tapered connecting channel (5) running from one chamber to the other, and eddy reducing or eliminating wall surfaces (6) running over only a part of the cross-section of the connecting channel provided in the tapered connecting channel. The wall surfaces are formed by cooling tubes, and have a structure slightly twisted in a longitudinal direction. A cooling groove that collects the slag at a lower end of the wall surfaces in the direction of gravity is provided for releasing the slag from a quenching chamber. The cooling tubes forming the wall surfaces have lower tube regions of tubes adjacent to each other in the direction of gravity to a distance bridged by a collecting base. The collecting base flows into the slag-releasing groove. The diameter of the tapered channel is 0.1-0.5 of the diameter of a gasification reactor. A remaining clear width in the interior through the vertical marginal edges of the eddy reducing wall is greater than 500 mm. A firing angle of 5-10 degrees is provided related to a secant of a burner arrangement likewise other swirl body and installations to reach an increased circulation in the gasification reactor and an intensive mixing. The tapered connecting channel is equipped with a neck having a dripping edge at its lower lying end in the direction of gravity. The neck at the connecting channel is surrounded by a further mixing tube for forming an additional mixing chamber. The inner side of the wall of the mixing tube is metallically formed. The diameter of the mixing tube and the distance of the free edges of the mixing tube are adapted to the solidification behavior of the occurring slag relative to the dripping edge. The idealistically resulting extension angle ( alpha ) between the dripping edge and the free edge of the Mixing tube is 10-30 degrees . The radius of the further mixing tube is 0.1-1 m larger than the radius of the dripping edge.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic representation of a pressure container with a reactor and a quenching chamber.    Reactor (1)    Pressure container (2)    Tapered connecting channel (5)    Wall surfaces (6)    Mixing region. (7)