Corrosion & Protection of Top Recycle Heat Exchanger of Main Fractionator in a FCC Unit

Morphology observation, composition analysis of corrosion products and leaked raw oil were used to study the corrosion reason of top recycle heat exchanger in a FCC unit. The results show that the corrosion caused by ammonium chloride was the major failure cause of the top recycle heat exchanger. In order to solve the problem, anti-corrosion suggestion of painting the tube with anti-corrosion coating was presented and proved to be effective in mitigating the corrosion of the top recycle heat exchanger.