The major challenges of CO2 capture by alkanolamines are associated with corrosion process. In this paper, the corrosion characteristics of carbon steel were analyzed in the air-cooled heat exchanger (ACHE) of a petrochemical plant in Kermanshah, Iran. The chemical analysis, weight loss method, electrochemical techniques, and eddy current measurements were applied to determine corrosion products and corrosion rate. Computational fluid dynamics was also applied to search for the links between the observed patterns of attack seen in the amine plant’s heat exchanger tubes and the hydrodynamics inside the tubes. Validation of the computational fluid dynamics results was compared with the visualized model of the tubes in the first pass of ACHE header. It was found that the erosion–corrosion damage was a consequence of increased levels of turbulence at tubes’ inlet, caused by a rapidly turning flow. An alternative flow correction was numerically investigated applying another nozzle in the first pass header of inlet flow and were recommended for implementation. As a result of the proposed configuration, the maximum wall shear stress was reduced from 90 Pa to 40 Pa in the inlet tube. Furthermore, the length of high wall shear stress region was decreased from 15 cm to 5 cm.