Abstract: The technological complexity of the million-ton ethylene plants, characterized by intricate process flows, diverse equipment types, and overlapping effects of corrosion mechanisms, renders corrosion analyses of individual equipment during routine operations insufficient for fundamentally resolving corrosion challenges. This paper analyzes the corrosion mechanisms within the plant, investigates the typical corrosion issues and proposes anti-corrosion measures for both processes and equipment. It conducts systematic research and analysis of corrosion conditions in the entire ethylene plant during major overhaul shutdown to validate and optimize corrosion prevention and control measures. After comparing the similarities and differences in corrosion conditions over nearly two cycles, the key areas for corrosion prevention in the next operating cycle of the ethylene plant have been identified. This provides theoretical support for the long-term operation of the ethylene plant and ensures its reliable operation.

Key words: million-ton ethylene plantlshutdown overhaullcorrosion mechanismlanticorrosive measures