Abstract: Through understanding the design conditions, operation and use of reboiler bundles at the bottom of the stabilizers in 20 sets of catalytic cracking units, it is summarized that the main failure forms of reboiler bundles at the bottom of the stabilizers in the application process are sulfide corrosion and vibration wear/fracture. The main factors affecting sulfide corrosion are the formation of gas phase space or scaling in the upper tube bundle, resulting in a significant increase in the temperature of the outer wall of the tube bundle and the increase in sulfide concentration, which produces serious corrosion problems; the main factors affecting the vibration of the tube bundle are the structural design, process conditions and operation control of the heat exchanger. Combined with the field application, standard specifications and design experience, the dual measures of corrosion prevention and vibration control are proposed to solve the leakage problem of reboiler tube bundles.

Key words: catalytic cracking unit/CCU, reboiler bundles at the bottom of stabilizer, corrosion, material selection