PREDICTION OF ALLOY CORROSION IN THE SHELL COAL-GASIFICATION PROCESS

Corrosion concerns for metallic materials of construction for gasifier and syngas cooler components for intermediate BTU coal gasification processes are analysed in the context of materials performance in the Shell Coal Gasification Process (SCGP). High temperature gas-phase corrosion, high temperature corrosion fatigue, dew point corrosion, and shut-down corrosion are discussed. The status of corrosion prediction and alloy selection capabilities is shown to be adequate for commercial equipment. Similarities in materials requirements and behaviour between several processes and processing conditions are pointed out. Much of the corrosion prediction and alloy selection information needed to build successful commercial plants is available without the need to develop or evaluate new alloys and has been demonstrated in an SCGP demonstration plant.