Protection Effect of Polyamine Used for 20 Steel in a Power Plant Environment

Polyamine is a new feedwater additive in steam generators. The protection effect of a kind of polyamine compound for 20# steel under a stimulated condition of 15 MPa and 342 ℃ was investigated. Its corrosion inhibition for 20# steel was studied by polarization curves and electrochemical impedance spectroscopy in 50 mg/L Cl- + 50 mg/L SO42- solution. The results show that the polyamine compound resulted in a positive shift of the corrosion potential and depressed the anodic corrosion reaction. It had the best inhibition effect at the addition of 15 mg/L. The spot test in a power plant verified that it had good wet shutdown protection ability. It is an alternative option for the hydrazine feedwater additives.