Integrity assessment and rehabilitation recommendation of the stripper section of a FCC reactor in the creep regime

:This paper describes the integrity assessment of the shell of the striper section of a FCC reactor in an oil refinery that was severely overheated due to the fall of the internal refractory lining. Because it was not possible to shut down the plant, it was decided to keep the reactor on service thus making necessary to estimate the time that reactor could operate in the creep regime just before a critical condition would be reached. Afterwards, once the reactor was set out of service, the owner requested a rehabilitation method that allowed the damaged section to continue in operation, due to the need to return to service as soon as possible. By using the methodologies of the standard API 579/ASME FFS-1 2007 Part 10, the remaining life time in the creep regime of the cylindrical section of the stripper was estimated and then a suitable time of safe service was recommended. After this, the extent creep damage was evaluated by non destructive inspection and an external reinforcement was designed, following the methods and guides of the API Bulletin 2U to ensure the vertical stability of the damaged cylindrical shell of the striper section of the FCC reactor. The analysis and recommendations proven to be adequate, since the FCC reactor has been operated for more than five years without failure.