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Event name: Water in the reforming feedstock; the catalyst suffered minor damage. Time of occurrence: 18:00 on October 15, 1998. Course of the event: At 18:00 on October 15, 1998, the shift supervisor in charge of reforming operations noticed that the high-level indicator for pre-hydrogenation was showing a higher value than normal. Upon inspection, it was found that there was a significant amount of free water in the feedstock buffer tanks D-3101, D-3102, and D-3103; this led to the conclusion that water was present in the feedstock. Immediate actions were taken to remove water from the feedstock, but it was discovered that the feedstock had become severely emulsified. During the period of water presence, the pressure drop in the pre-hydrogenation reactor R-3101 increased. Due to fluctuations in the operation of C-3101, the purity of the reforming cycle hydrogen declined (the on-line moisture meter indicated it was at the lower limit). The exhaust temperature of the cycle pump reached 125°C, the current level was 180A, and an alarm was triggered when the motor stator temperature exceeded 120°C. The operators intensified the dehydration efforts, and by 22:00, all water from the feedstock had been removed. At 4:00 on the 16th, an increase in water content in the reforming cycle hydrogen was detected; by 10:30 it had reached 180 ppm. The plant took measures to reduce the temperature of each reforming reactor below 480°C, stopped the injection of water, and increased the chlorine injection volume. On October 20, the water content in the air dropped below 50 ppm and returned to normal. Due to the timely discovery, the impact on the catalyst was minimal. Cause analysis: The water content in the emulsion of straight-run gasoline delivered is the main reason for water shock to the reforming catalyst. Precautionary measures: Conduct regular inspections; dehydrate D-3101 and D-3103 every 2 hours ； The operator should strengthen monitoring; an increase in the level in D-3102 or an increase in water content in the recycled hydrogen can indicate the presence of water. Upon detecting the presence of water, it is necessary to report to the headquarters immediately; the oil should be subjected to enhanced dehydration or transferred to another tank. At the same time, enhanced dehydration processes should be carried out in units D-3101, D-3103, and D-3102, and the operation of the evaporation tower must be adjusted to prevent water from entering the hydrogen system used in the reforming process. When a large amount of water cannot be controlled, report to the workshop and consult the main control room to stop feeding the unit, in order to prevent damage to the reforming catalyst. After water shock to the reforming catalyst, the reaction temperature should be reduced immediately to below 480°C, water injection should be stopped, molecular sieve dehydration should be employed if necessary, and the chlorine injection rate should be increased.