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Taking into account the locations of S-H2S-RSH corrosion, its influencing factors, and mitigation measures discussed earlier, the corrosion rate can be monitored and controlled using the following methods: 1. Methods for monitoring corrosion rate – Fixed-point/online thickness measurement: At high-risk and corrosive areas such as furnace tubes and vacuum transfer lines, ultrasonic fixed-point thickness measurements can be carried out regularly, or online thickness measurement systems can be installed to obtain real-time data on wall thickness changes, thereby automatically calculating the corrosion rate. Medium and probe monitoring: Regularly analyze the sulfur content of raw materials and the iron ion concentration in the side-stream oil, to indirectly determine the corrosion rate ； Appropriate high-temperature corrosion probes can also be installed at the sites affected by high-temperature corrosion to monitor the real-time corrosion rate online. Special inspection during shutdown: During the maintenance period of the plant, a detailed corrosion inspection is carried out on the components inside the tower sowie on those locations where there are sudden changes in flow velocity, such as the inlet and outlet areas of heat exchangers, in order to reevaluate the actual corrosion rate during operation. II. Measures to control corrosion rate: Material corrosion protection – Use corrosion-resistant steel grades such as Cr5Mo, Cr9Mo, 1Cr18Ni9Ti, or 20R+0Cr13 composite sheets to reduce the corrosion rate at its source. Process optimization: Strictly control the operating temperature to avoid prolonged exposure to the highly corrosive range of 350–430°C ； Optimize the flow channel design to reduce the fluid velocity and minimize the erosion and removal of the FeS protective film. Process anti-corrosion adjustment: Adjust the process anti-corrosion measures in a timely manner based on changes in the monitored corrosion rate, to prevent leakage risks caused by excessive corrosion rates.