Synthetic Ammonia Process Technology Exchange Area [Daily Question 2009-03-14] How to diagnose, handle, and coordinate the tripping of the shift hot water pump?

Judgment: The liquid level in the saturated tower drops rapidly, while the liquid level in the hot water tower rises rapidly. If there is no liquid level in the saturated tower and the water seal fails, it may also lead to gas leakage; simultaneously, gas can also leak through the hot water pump, resulting in high levels of carbon monoxide after the conversion process. Action: Quickly close the outlet valve of the tripped hot water pump. The standby pump was quickly started; while adjusting the liquid levels in the two towers, the duty dispatcher was informed, as well as the relevant sections such as copper washing and synthesis.

What if the standby pump cannot be started after a long time?

If the situation is as on the second floor, handle it as follows: The team leader should contact the dispatch team to reduce the volume of flow, inform the technicians that the hot water pump has tripped, and alert the synthesis unit to pay attention to the CO levels in order to prevent overheating； ·The operator controls the liquid level in the saturated hot water tower, increases the steam consumption, prevents CO levels from rising too high, and maintains close coordination with the synthesis process ； ·The team leader promptly contacted the electrician to check the motor of the backup hot water pump; once it was found to be in good condition, power was supplied and preparations were made before starting the pump ； ·After confirming that everything is normal, the team leader contacts the operator to start the backup hot water pump following the standard startup procedures, gradually increasing the circulation volume ； ·Once the system returns to normal, contact the dispatch team and increase the compression level to the normal setting.

As soon as possible, close the valve from the saturated tower to the hot water tower before a water seal is in place. Other measures are as mentioned above. This post was last edited by jingsan on 2009-3-13 13:52]

Judgment: The tripping of the hot water pump can be determined using the liquid level, CO detector, and system water temperature gauge, among other devices! Action: It is indeed the hot water pump that has tripped. The assistant operator should be instructed to inform the dispatch team and the relevant departments, while simultaneously introducing a large amount of steam into the system. Then the pump outlet should be closed and a backup pump activated as a contingency measure (since our liquid level is automatically regulated, there is no need to rush to shut down the water seal), so as to maintain a roughly equivalent flow rate. If the standby pump cannot be started, measures should be taken to bring the emergency pump into operation immediately, and the dispatch center as well as relevant personnel such as electricians and machine operators should be notified. When the exhaust pressure of the emergency pump rises, the outlet should be opened slowly, and the normal hot water flow rate should be gradually adjusted to. The above are only the methods for dealing with hot water pumps in case of electrical failures. If the pump body is faulty, that’s a different matter. This post was last edited by snowdfr on 2009-3-13 19:33]

The liquid level in the saturated tower drops, while the liquid level in the hot water tower rises. If there is no liquid level in the saturated tower, the temperature of the water entering the tower rises sharply, while the temperature of the gas exiting the tower drops. If the water seal fails to function properly, it may lead to air leakage, resulting in an increase in CO levels at the system outlet. Actions to take: 1. Increase the steam supply to control the CO level at the system outlet; inform the relevant teams, and if necessary, reduce production volume or ask the copper washing unit to operate additional copper pumps (in the case of methanol or methanation, it is sufficient for the relevant teams to adjust the temperature or increase the load). 2. Close the U-tube valve of the hot water saturation tower to prevent air from mixing in. Close the pump inlet and outlet valves. 3. For the process with a No. 0 bypass line (a shortcut for the gas stream from the shift converter designed to increase the ammonia-to-alcohol ratio), this bypass line should be reduced in flow or shut off. 4. Quickly reverse the pump and notify personnel to inspect and repair it.