An Exploration of Corrosion in the HF Neutralization Section at Linear Alkyl Benzene Production Plant

Document Type : Research Article


Department of Chemistry, Payame Noor University (PNU), Tehran, I.R. IRAN


Hydrofluoric acid (HF) is a catalyst for the production of linear alkylbenzene (LAB). In this research, the corrosion and perforation in the overhead line of HF neutralization section in Bistoun Petrochemical Company (BPC), in Iran was investigated. The accumulation of sediment and under deposit corrosion has resulted in the perforation of the mentioned line. The main causes of failure were explored by visual checking, chemical characterizations, Scanning Electron Microscopy (SEM), and X-Ray Fluorescence (XRF). The effects of process conditions, pipeline design, water content, and oxygen amounts were studied. Corrosion and perforation in the line are based on the composition of the liquid or gases passing through the line and operating conditions. The reverse return of water vapors contaminated with KOH from the relief gas scrubber to the overhead line can accelerate the corrosion. Lastly, the suggestions have been proposed for troubleshooting, prevention from failure in the line, and HF leakage.


Main Subjects

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