Ammonia vapor with liquid entrainment

Check if there is a problem with the demister screen at the top of the ammonia cooler

The reason might be the poor performance of the demister at the top of the ammonia cooler; in addition, it is necessary to verify whether the liquid level is accurate.

First, check whether the level gauge is accurate; having liquid in the system does not necessarily mean that the level is high. A damaged demister, a high level of liquid in the user’s separator, or pressure fluctuations can all cause liquid to be present in the system.

At 5 degrees, the saturated vapor pressure of liquid ammonia is 5.26 kilograms; gas ammonia will not liquefy during transportation if it is not pressurized or cooled. The presence of liquid is likely due to ammonia carrying liquid at the outlet of the ammonia cooler; it is necessary to check whether there are any issues with the demisting baffle in the ammonia cooler as well as the liquid dropping tube of the demister.

One more thing: to prevent the presence of liquid, regarding the ammonia cooler, it is necessary first to conduct regular inspections of the equipment to ensure it is in good condition, and second, to operate it as smoothly as possible, avoiding large fluctuations. For the user side, it is necessary to strengthen the monitoring of the separator level; a temperature monitoring point should be installed behind the separator. Whenever there is slight contamination with liquid, the temperature will drop significantly, which can help prevent accidents caused by severe contamination.

The main reasons for liquid presence are as follows: 1. The liquid level in the ammonia evaporator is inaccurate, with the indication being too low； 2. The insulation of the gaseous ammonia pipeline is inadequate; as the temperature drops during the transport of ammonia to the compound fertilizer, some of the gaseous ammonia condenses ； 3. The ammonia addition rate to the ammonia evaporator is too high, resulting in liquid being carried along with the gaseous ammonia ； 4. The demisting effect of the gas-liquid separator on the ammonia gas outlet pipe is poor ； 5. Significant fluctuations in gaseous ammonia pressure.

Our ammonia cooler doesn’t have a gas-liquid demister, and there’s no significant change in the liquid level; the pipes are also insulated

Our ammonia cooler doesn’t have a gas-liquid demister, and there is no significant change in the liquid level. The pipes are also insulated; the main reason is the absence of a separation device. Neither high nor low liquid levels are that important; we all have low liquid level zones. The most important thing is your outlet pressure, 0.3 MPa; the gas flow rate is quite high. When boiling is severe inside the ammonia cooler, entrainment occurs. I suggest you add a separation device. I don’t think there’s any problem with the pipes. Many experts upstairs have mentioned various possible reasons. You should also pay attention to those issues in your actual work. Because it does happen quite often. For the user side, it is necessary to strengthen the monitoring of the separator level; a temperature monitoring point should be installed behind the separator. Whenever there is slight contamination with liquid, the temperature will drop significantly, which can help prevent accidents caused by severe contamination. Why is the monitoring point after our separator free of liquid, while the main pipe 5 meters further along has liquid in it? This problem is not unsolvable. This post was last edited by steinback on 2009-2-22 10:14]

At what temperature can ammonia turn into liquid ammonia?

I think it should be analyzed from the following aspects: 1. Check whether the level gauge is clogged. 2. Are the demister and the downcomer of the ammonia cooler operating properly or are they clogged? 3. It is also possible that high pressure and high temperature, along with a fast gas flow rate, and the absence of heating equipment in the area where the compound fertilizer is produced, can result in the formation of a small amount of liquid ammonia. 4. Due to the high saturation of gaseous ammonia in the delivery pipeline, a small amount of liquid ammonia is also formed during transportation.