Abstract: The outlet pipeline of slurry pump for FCC unit was taken as the research object. Based on the analysis of high-temperature sulfur corrosion and erosion mechanisms, a numerical simulation method for predicting damage characteristics of pipelines in the presence of both corrosion and erosion was established. The distribution of the flow field parameters, the concentration of the corrosive medium and the collision angle of the solid catalyst were obtained by coupling multi-physical field models. The parameters such as erosion rate, corrosion rate, and surface thinning rate were used to quantitatively characterize the damage rule. The results showed that the irregular movement of solid particles could be driven by high pressure and turbulent flow pattern, which resulted in a large risk of erosion and wear; the distribution of the corrosive medium near the wall of the pipeline was not uniform. Under the synergistic action of erosion and corrosion, the average damage rate of pipeline wall was 0.46 mm/a, and the maximum damage rate was 0.55 mm/a. The damage behavior and thinning rate predicted by the model were in good agreement with the experimental results, which could provide support for monitoring and life prediction of pipelines.

Key words: FCC slurry, sulfur corrosion, erosion, damage behavior, numerical simulation