In catalytic cracking, when reaction pressure occurs, the distillation pressure rises sharply, the pressure at the compressor inlet drops sharply, and then it returns to normal automatically
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Recently, catalytic cracking has been experiencing sudden increases in reaction pressure and distillation pressure, as well as a sharp drop in the pressure at the compressor inlet; afterwards, these conditions return to normal automatically
This phenomenon occurs frequently; it is likely due to water suddenly entering the vaporization section of either a reaction settler system or a fractionation tower system, thereby causing this issue； It is possible to check whether there is any change in the level of the oil-gas separator at the top of the fractionation tower. This situation occurs frequently; it should not be a problem with the butterfly valve at the top of the fractionation tower. Check the steam entering the two systems to see if there is intermittent entry of condensate water into the system.
1. It is suspected that the liquid level in the reflux tank at the top of the fractionation tower is too high, indicating a false liquid level. II. Check whether the cold reflux contains water.
Check whether there is any change in the cooling temperature of the oil and gas at the top of the splitter tower, and whether it is affected by temperature
Check whether the cold return flow or the top circulation return flow contains water
The effect of temperature shouldn’t be that great.
OP, have you found the reason? Reply to the message
Based on the pressure responses observed in your case, the fractionation pressure rises suddenly, the pressure at the compressor inlet drops sharply, and then it returns to normal automatically. It is likely that the top air cooling or coolant misdirection has created a local liquid seal, affecting the pressure. Adjust the average number of air-cooled operations; try to eliminate flow deviation by adjusting the cooling water volume or the opening degree of the outlet valve based on the outlet temperature of the coolant medium.