This paper summarizes results of a joint industry program (JIP) to address ammonium bisulfide (NH 4 HS) corrosion in H 2 S-dominated alkaline sour waters typically found in refinery services such as the reactor effluent air cooler (REAC) systems of hydroprocessing units. The impacts of several process variables on corrosion were quantified. Key learnings support a paradigm shift from the rules of thumb previously applied to these systems. Data collected were used to develop a software tool to predict the corrosion rate of 14 materials evaluated in the program.
Keywords: sour water, ammonium bisulfide, NH 4 HS, hydrogen sulfide, H 2 S, partial pressure, isocorrosion diagram, temperature, chloride, hydrocarbon, velocity, wall shear stress, ammonium polysulfide, APS, imidazoline, materials selection, software, reactor effluent air cooler, REAC, hydroprocessing, refining