With a method for removing slag, particularly slag that occurs during synthesis gas extraction, from a slag bath situated in a pressurized container, into a collection container for the slag, below the slag bath in the direction of gravity, a device for breaking up the slag is provided below the slag bath, and a sluice valve is provided between the containers. A space filled with a gas bubble, which space stands in contact with the liquid in the containers, particularly a ring space or a separate container, is provided, in which the pressure of the gas bubble is regulated by supplying gas. At least a part of the water situated in the slag sluice/collection space flows through the slag bath valve when the latter is opened, in the direction of the slag bath, counter to the direction of gravity.