Problems with radiation pumps in delayed coking
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This post was last edited by lijianhuai on 2012-4-28 09:41. What should be done with the entire plant if the radiation pump stops operating or runs out of fluid during normal production in delayed coking? The more detailed, the better
The reasons for the sudden shutdown include: 1. Whether the relevant interlocks of the heating furnace were triggered； 2. Other key process parameters exceeded, resulting in a interlock of the radiation feed pump ； 3. Power outage of the device ； The reasons for the interruption are: 1. Water in the seal oil ； 2. The steam system connected to the pump body enters the pump body ； 3. The temperature at the bottom of the distillation tower is too low, resulting in the oil product having too low a density and causing vapor resistance inside the pump ； 4. Pump installation location ； Treatment: Shut off power and activate the steam reciprocating pump to circulate fluid throughout the entire system ； Check whether the steam valve connected to the pump is properly closed; under normal circumstances, it should be isolated using a blind flange. Increase the temperature of the evaporation section. Inspect the seal oil system and make timely corrections; if that doesn’t work, introduce seal oil from outside the unit. Adjust the installation position of the pump
Vacuum in the radial feed pump 1. Symptoms: 1) The radial feed volume drops to zero, triggering an alarm. 2) The furnace radiation outlet temperature rises sharply. 3) The pressure at the furnace radiation inlet drops sharply. 4) The pump makes abnormal noises and the current level drops. 5) The liquid level in the distillation tower rises. 2. Reasons: 1) The liquid level at the bottom of the distillation tower is too low. 2) Steam entrainment at the pump inlet. 3) The sealing oil contains water, is too light, or the amount of sealing oil is excessive. 4) The filter or inlet is blocked. 5) Fault in the pump itself. 3. Handling method: 1) The pump operator shall close the outlet valve of the standby pump, prepare the oil sealing device for turning the pump, and carry out an emergency pump swap under the supervision of the shift leader. 2) The operator at the furnace should immediately shut down the fire (keeping the pilot light alive), increase the water supply. If it is not possible to start the pump in a short time, lower the temperature to 420°C and maintain it there; once the pump can be started normally, quickly reignite the fire to raise the temperature to normal levels. If the pump still cannot be started after some time, continue to lower the temperature to 350°C. 3) If the pump cannot start for an extended period, the steam pump can be started to supply oil to the radiator. 4) Introduce high-pressure gas into the system to prepare for reheating. 5) The distillation unit must maintain proper control over the liquid level in C-102. As the liquid level in C-102 rises, which leads to a decrease in flow rate, it is necessary to ensure that the temperature at the outlet does not exceed 370°C; convective venting can be used to control this outlet temperature. 6) The team leader must quickly identify the cause; if it cannot be resolved, they should request the workshop to initiate a shutdown and cooling cycle.
Is there water in the glaze sealant? What is the liquid level in the distillation tower? Is there water in the raw materials? Has the oil been changed in the irrigation system?
The relevant reasons and solutions for the 2nd and 3rd floors have already been analyzed. The radiant pump is the heart of coking. What I want to emphasize is that if there are problems with the radiant pump, the operators on site must immediately reduce the temperature and flow rate of the heating furnace, and increase the injection of steam or water, in order to prevent coking in the heating furnace. Until the cause is identified and resolved, the pump must be started to maintain production by operating it or shutting it down periodically; if necessary, the system should be put into circulation.
Not bad; it’s experience worth learning from. Study it carefully. . . :):):)
The core principle in dealing with a sudden evacuation caused by a radiation pump is to prevent the furnace tubes from overheating and coking; the crew must be aware of this principle, as otherwise unpredictable consequences can occur. Once an evacuation or shutdown is detected, steam injection should be increased promptly – at that point the furnace should already have activated its interlock system (low-flow interlock). If the interlock does not activate or such an interlock is not available, the furnace should be shut down manually immediately, while the remaining issues can be dealt with more slowly.
Continuing to study *; just starting to learn about refining units, still in the process of studying *