Effects on Flow-Accelerated Corrosion of Oleylpropanediamine Under Single-Phase Water Conditions Pertinent to Power Plant Feedwater

Studies of the effects of the film-forming amine oleylpropanediamine (OLDA), with and without auxiliary alkalizing agents, on flow-accelerated corrosion (FAC) were performed in high-pressure, high-temperature recirculating water loops. Those loops were equipped with experimental probes to monitor FAC in situ. Experiments were performed at simulated power plant conditions in single-phase water at 140°C. The results showed that OLDA reduced FAC to a greater extent than the associated pH effect. The protective film apparently consisted of several layers and survived for several days after OLDA was removed from the bulk water. The system treated with OLDA under neutral water conditions before raising the pH had higher corrosion resistance than the system dosed with OLDA when already at high pH.