Investigation of Corrosion in LPG Units: A Review of Causes, Mechanisms, and Mitigation Strategies

Corrosion in Liquefied Petroleum Gas (LPG) units poses significant challenges to the safety, reliability, and efficiency of refining and petrochemical operations. These units operate under high pressure and varying temperature conditions, exposing metallic equipment to aggressive environments containing corrosive agents such as hydrogen sulfide (H₂S), carbon dioxide (CO₂), moisture, and trace acidic compounds. The interaction of these substances with carbon steel and other commonly used materials leads to various corrosion phenomena, including uniform corrosion, localized pitting, and stress corrosion cracking. Sweet corrosion, primarily driven by CO₂, results in the formation of iron carbonate protective scales under certain conditions, while sour corrosion induced by H₂S forms brittle iron sulfide layers that exacerbate metal degradation. Additionally, microbiologically influenced corrosion (MIC) caused by sulfate-reducing bacteria further complicates corrosion management in LPG storage facilities. Effective corrosion control requires a multifaceted approach involving material selection, chemical inhibitors, protective coatings, and rigorous operational monitoring. Electrochemical techniques such as Electrochemical Impedance Spectroscopy (EIS) and Linear Polarization Resistance (LPR) are widely employed for real-time corrosion rate assessment. Despite advancements in mitigation strategies, corrosion remains a critical concern due to its impact on operational costs, safety hazards, and equipment lifespan. Continued research and development are essential to optimize corrosion prevention methods and enhance the durability of LPG processing and storage infrastructure.

کلیدواژه ها:

LPG units ، corrosion ، Hydrogen Sulfide ، Carbon dioxide ، sweet corrosion