The reflux pump at the stabilizer top stopped operating due to a fault, and the backup pump failed to start in time; accident handling was carried out
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In the catalytic cracking unit, the reflux pump at the top of the stabilizer (liquid hydrocarbon pump) is malfunctioning, and the backup pump is not available for use. How does everyone handle such situations? (The stabilizer has no mid-section reflux; the heat source for the bottom reboiler is the oil from the first fractionation stage.)
Remove the heat source at the bottom of the towers, transfer the crude gasoline to the tank area, stop feeding material to all towers, wait to deal with the reflux pump, reduce the reaction volume; if the situation persists for a long time, it may be necessary to cut off the feed. Gasoline containing large amounts of liquefied gas cannot be sent to the tank area. Last year, an accident occurred in one plant due to gasoline containing light hydrocarbons!
I’ve really never encountered this situation before; it’s probably due to the leakage of crude gasoline and the low temperature at the bottom of the tower. If necessary, the feed supply will have to be stopped
Switch the heat source at the bottom of the tower to external discharge; reduce the reaction volume and cut off the feed if necessary. Stabilize the three-tower cycle and carry out emergency repairs on the pumps. Control the pressure in each tower properly
Prolonged interruption stops absorption and maintains stability
Stable three-tower circulation on the 4th floor? I don’t think it’s possible
Expel rough gas externally, shut down the stabilization system, and release dry gas at low pressure
If that’s the case, air cooling and water cooling should be activated promptly. If it’s really summer, turning on air cooling seems to not be very effective either. Appropriately reduce the heat source of the reboiler at the bottom of the stabilizer to lower the temperature at the tower bottom. Increase the volume of liquefied gas sent for purification; at the same time, adjust the non-condensable gas in the reflux tank in a timely manner to maintain proper pressure levels
Remove the heat source at the bottom of the tower to lower the temperature; transfer the unqualified gasoline to designated storage tanks. Activate the air cooling at the top of the tower and increase water cooling. If pressure becomes too high, it can be vented through a flare to relieve pressure. Try to maintain absorption and stability at all costs, as stopping operations results in greater losses than using a flare; the more changes there are, the greater the risks.