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To address the corrosion in the RNH₂-CO₂-H₂S-H₂O system, protection measures can be taken from various aspects such as material upgrading, structural optimization, and process control. The specific measures are as follows: Material upgrading and optimization – In areas with high corrosion risk (such as the reflux lines of reboilers and the tube bundles of reboilers), carbon steel should be replaced with 304/316L stainless steel or 1Cr18Ni9Ti steel tubes. For heat exchange tube bundles operating at temperatures above 120°C, austenitic stainless steel must be used to prevent rapid corrosion and thinning of carbon steel in this system. Structure and heat treatment protection: Carbon steel equipment and pipelines operating at temperatures above 90°C require post-weld stress-relief heat treatment to keep the hardness of the welds and heat-affected zones at or below HB200, thereby preventing carbonate stress corrosion cracking ； Stainless steel impact shields with matching areas are installed in the back-to-tower impact zone, and steam distributors are added to optimize the flow field and reduce erosion corrosion. Control of process conditions: Strict control is exercised over the temperature at the bottom of the regeneration tower – it should be maintained at 120°C for MEA systems and 115°C for DEA systems. The operating temperature of the reboiler must not exceed 140°C, in order to prevent excessive corrosion caused by the high-temperature decomposition of amines ； The amine storage tank is sealed with an inert gas to isolate oxygen, thereby reducing the oxidation and degradation of the amine solution and the formation of corrosive organic acids. Auxiliary protection measures include injecting specialized corrosion inhibitors into the monoethanolamine system, as well as installing high-precision filters on the pipelines to remove solid impurities such as iron sulfide and iron oxide from the amine solution. This prevents solid particles from damaging the metal protective layer and causing wear and corrosion.