Corrosion Analysis in Catalytic Reforming Units (CRU): Causes, Data Evaluation, and Mitigation Strategies

Catalytic Reforming Units (CRUs) are essential components in petroleum refineries, producing high-octane gasoline and aromatic hydrocarbons through the transformation of naphtha under high-temperature and hydrogen-rich conditions. However, these operational environments are highly conducive to several corrosion mechanisms, including chloride-induced corrosion, sulfidation, and stress corrosion cracking (SCC). This study investigates corrosion phenomena in CRUs by analyzing five years of operational and inspection data from a refinery in southern Iraq. Key variables such as temperature, chloride and sulfur concentrations, and hydrogen-to-hydrocarbon ratios were examined in relation to corrosion rates observed in critical areas like reactor effluents, heaters, and separators. The results reveal a progressive increase in corrosion rates from ۰.۱۸ mm/year in ۲۰۱۶ to ۰.۳۹ mm/year in ۲۰۲۱, primarily correlated with rising chloride content and operational temperatures. Notable equipment failures, including tube ruptures and cracking near welds, were directly linked to under-deposit corrosion and SCC. Regression analysis showed a strong correlation (R² = ۰.۸۶) between chloride levels and corrosion severity. Based on the findings, the paper proposes a set of mitigation strategies including material upgrades (e.g., Alloy ۶۲۵), improved water washing systems to control chlorides, enhanced corrosion monitoring, and chemical treatments. The study emphasizes the importance of proactive corrosion management to extend equipment life, prevent unscheduled outages, and reduce operational risks in CRU operations.

کلیدواژه ها:

Catalytic Reforming Unit (CRU) ، corrosion ، Chloride-induced Corrosion ، Sulfidation