Corrosion cause analysis and countermeasures on depentanizer of continuous reforming unit

Aiming at the equipment corrosion problems of the depentanizer system of continuous reforming unit in a petrochemical company, through adopting the methods including macro inspection, eddy current testing, and corrosive analysis of the corrosion location, consulting relevant references, and analyzing the corrosion causes and corrosion mechanism of the key parts, it concluded that ammonium salt deposition was the main cause of depentanizer air cooler corrosion and leakage. Effective measures were put forward as follows: (1) Control the nitrogen content in the raw material; (2) make water washing on depentanizer overhead; (3) fill corrosion inhibitor; (4) replace efficient dechlorination agent; (5) update the material of easy corrosive parts; (6) strengthen the on-line corrosion detection method.