Corrosion assessment of Amine regenerator column of SPGC using process simulation in gas sweetening unit to mitigate corrosion rate by controlling process parameters

The destructive corrosion phenomenon has been identified as one of the major problems in the Iranian gas refineries, which is often found in the amine regenerator tower and the steam condensate regions of carbon dioxide. One of the most important causes of this problem is the lowering of the amine temperature below the safe operating temperature range. According to the simulation of the process performed using ProMax software, in the event of a drop in the temperature of the amine entering to the regenerator tower, mainly at the bottom of the tower, as well as the reboiler, which according to the body (carbon steel 516), the corrosion is likely to occur. Examining the corrosion coupon installed in this gas sweetening indicates an increase in the corrosion rate, which can increase up to 1.27 mm/year if the process conditions in the amine cycle are not controlled. Stereo microscope images and identification corrosion product by x-ray diffraction used in this study confirm the above item. Finally, different strategies for controlling the temperature of the amine to the tower in the operational safe area are presented in accordance with the strategies of each refinery, as well as considering the cost of the life cycle. The above solution may include designing and adding a new heat exchanger or periodic cleaning to identify the sediment formed in the amine-amine plate converter.