Failure analysis of one peculiar ‘Yin-Yang’ corrosion morphology on heat exchanger tubes in purified terephthalic acid (PTA) dryer

Failure analysis on unexpected wall thinning of heat-exchange tubes in ammonia evaporators

“…Owing to diverse situations, it became hard to explain this wall-thinning case by above mechanisms described in literatures. Hence, based on our recent work on failures analysis of various heat-exchange tubes [9][10][11][12][13][14], systematic investigations were conducted to find out the real cause of this incident, including external appearance, microscopic morphology and chemical composition, and then practical prevention measures were also proposed. Overall, the analysis in this paper will provide a reference with significant engineering value to prevent failure recurrence of ammonia evaporators under similar operating condition.…”