One of our amine tanks was opened and inspected. A corrosion was discovered in the vapor space , above the liquid level. The scale was not passivating, it was flaking and multi layered in places, it retained considerable moisture and had patches of visible salt deposits.
The tank is N2 blanketed. Recommendation is to apply an internal coating to the tank shell and roof to prevent futher internal corrosion in the vapor space; .
Service: Lean Amine, DT 120C, DP 15mbarg, OT 60C, OP 5mbar (N2 blanket)
Dimensions: 5700dia x 10450high
Process Liquid: 0.02 mole% H2S, 0.09 mole% CO2, 92.1 mole% H2O, 7.8 mole% DEA
Tank material: LTCS
The tank is N2 blanketed, but has obviously experienced episodes of air entrainment.
Does anyone have a recommendation for internal coating material ??
