Patent ID: 8317885

Claim:
An apparatus for gasifying a fuel to form synthesis gas wherein also a slag is formed, the apparatus comprising: a pressure shell for maintaining a pressure higher than atmospheric pressure; a slag bath located in a lower part of the pressure shell, the slag bath comprising a quench fluid; a gasifier wall arranged inside the pressure shell defining a gasification chamber wherein during operation the synthesis gas can be formed, a lower part of the gasifier wall comprising a converging wall part that is provided with a slag discharge opening having a dripper edge located above the quench fluid in the slag bath; an open space forming a free-fall trajectory for the slag, the open space extending downwardly between the slag discharge opening and the slag bath; and a heat shield arranged below the dripper edge and above the slag bath between at least part of the free-fall trajectory and the pressure shell, the heat shield comprising a wall structure for allowing passage of a cooling fluid, the wall structure comprising an upper wall part and an essentially refractory-free lower wall part, the upper wall part being located closer to the slag discharge opening than the lower wall part and the lower wall part being located closer to the slag bath than the upper wall part.