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

Document Type: Research Article

Author

Department of Chemistry, Payame Noor University (PNU), Tehran, Iran.

10.30492/ijcce.2019.35111

Abstract

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.

Keywords

Main Subjects


[1] Shokri A., An Investigation of Corrosion and Sedimentation in the Air Cooler tubes of Benzene Drying Column in Linear Alkyl Benzene Production Plant, Chemical Papers, (2019). [In Press]
[2] Li M.C., Zeng C.L., Lin H.C. and Cao C.N., Effect of Fluoride Ions on Passive Performance of 316 –Steel in Acid Media, Acta Metall. Sin., 37: 1083–1086 (2001).
[3] Stypula B., Kasprzyk D., Hajos M., Corrosion Behavior of –Steel in Hot Concentrated Sulfuric Acid – Effect of Fluoride Impurities, Arch. Metall. Mater., 54: 305–3317(2009).
[4] Pawel S.J., Corrosion of High–Alloy Materials in Aqueous Hydrofluoric Acid Environments, Corrosion, 50: 963–971(1994). 
[5] Valkenburg, E.G., “HF ISO Tanks Corrosion Evaluation. Confidential Internal Report: Part 1: PCM–OPSA60–REP–12007”, Pelchem SOC Ltd, Pelindaba, South Africa (2012).
[6] API Recommended Practice 751, “Safe Operation of Hydrofluoric Acid Alkylation Units”, 2nd ed., American Petroleum Institute, Washington, D.C., (1999).
[7] Zhu M., Ou G., Jin H., Wang K., Zheng Z., Top of the REAC tube Corrosion Induced by under Deposit Corrosion of Ammonium Chloride and Erosion Corrosion, Eng. Fail. Anal., 57: 483–489(2015).
[9] Hu S.M., Wang S.H., Yang Z.G., Failure Analysis on Unexpected Wall Thinning of Heat–Exchange Tubes in Ammonia Evaporators, Case Studies in Eng. Fail. Anal., 3: 52–61(2015).
[10] Blackburn F.E., “Non-Bioassay Techniques for Monitoring MIC, Conference Paper”, CORROSION, NACE International, Houston, Texas USA, (2004).
[11] Hansen D.A., Puyear R.B., “Materials Selection/or Hydrocarbon and Chemical Plants”, CRC Press, New York, USA (1996).  
[12] Deport R., Hero H.M., “The Nalco Guide to Boiler Failure Analysis”, McCraw-Hill Inc., (1944).
[13] Haynes W.M., “CRC Handbook of Chemistry and Physics”, 94th ed. CRC Press (2016).
[14] Sridhar N., Dunn D., Anderko A., Lencka M., Schutt H., Effects of Water and Gas Compositions on the Internal Corrosion of Gas Pipelines – Modeling and Experimental Studies, Corrosion, 57: 221–235 (2001).
[15] “Manual and Document of Alkylation Unit of Bistoun Petrochemical Company in Iran”.
[16] Hashim H.H., Valerioti W.L., Corrosion Resistance of Carbon steel in HF Alkylation Service, Materials Performance, 50(1993).
[17] Helle H.P.E., “Guidelines for Corrosion Control in HF–Alkylation Units”, 2nd ed., New Plantation, Delft, Netherlands, (1993).
[18] Penuela L., Chirinos J., Inspection Program Evaluates HF Alkylation Carbon Steel Piping, Oil and Gas Journal, 97(22): 55–57(1999).
[19] Jennings H., “Materials for Storing and Handling Commercial Grades of Aqueous Hydrofluoric Acid and Anhydrous Hydrogen” Fluoride (No. 24057). NACE International Publication 5A171 (2007).