delayed coking
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Both the top recirculation pumps of the delayed coking fractionation tower have stopped, but production continues. What are the implications? It is currently known that the temperature at the top of the stabilizer cannot be reduced. Later, the water cooling inlet at the top of the stabilizer was increased in size, but the effect was not very significant; ultimately, it became impossible to lower the liquid level in the stabilizer. . . . . . What’s going on? Please help........
What is your process like? If the top circulation pump stops, it can cause the gasoline’s dry point to be below the required standard, but it’s possible to maintain the conditions by using cold reflux
The general process is the same; I’m wondering what effect the shutdown of the top circulation pump has on the temperature and liquid level of the stabilizer, which is responsible for maintaining stability. What medium does the cold reflux flow consist of? Is it crude gasoline?
Yes, cold reflux refers to crude gasoline. If your top circulation stops, it will only have a certain impact on the dry point of crude gasoline; it will not affect stable operation
Oh...... thank you, but why is this happening to our stabilizer tower? Then the distillation column top pump was restored; it will be fine on our end in a short while........
Without cold reflux in the stabilizer tower, the heat load on the tower increases. Relying on water cooling at the top of the tower is ineffective; since the feed temperature remains unchanged, an increase in pressure at the tower top leads to reduced evaporation, and ultimately the liquid level in the stabilizer tower fails to drop. If the time frame is short, the extraction and circulation rates of the other circuits can be increased appropriately to reduce the heat load on the stabilizer tower, thereby enabling the circulation pump to be restored as soon as possible. If it is over a long period of time, the machine must be stopped, as it will affect product quality.
The shutdown of the top circulation pump led to substandard quality of crude gasoline. The crude gasoline reaching the absorption tower did not perform well as an absorbent, resulting in excessive levels of carbon 1 and carbon 2 components in the absorbent, which in turn affected the stabilization system. You need to increase the cold reflux in order to reduce the temperature gradient in the distillation column, thereby lowering the temperature at the top of the distillation column