Liquid in the chiller issue
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What are the causes of liquid carryover in the chillers used in ammonia synthesis systems and frosting on the inlet pipes?
Both of these problems are likely caused by a low inlet temperature of the ice machine. Properly adjusting the load on the economizer and maintaining an appropriate inlet temperature for the ice machine are effective ways to resolve this issue.
The liquid presence in the inlet pipeline of the ice machine is related to the liquid level in the ammonia cooler; excessive liquid leads to a high liquid level, while a small amount of liquid results in a slightly higher liquid level in the ammonia cooler. The handling method is as follows: 1. Quickly contact the synthesis team to lower the liquid level in the ammonia cooler. 2. When a small amount of liquid is present at the inlet of the chiller, the valve connected to the chiller should be slightly opened, so that the temperature at the outlet can be used to heat and evaporate the liquid ammonia entering the system. 3. Stop the machine immediately when there is a large amount of liquid present.
When ammonia is added to the ammonia cooler too quickly or in excessive amounts, the liquid level rises, and the liquid ammonia cannot vaporize in a timely manner. It will be carried into the chiller inlet along with gaseous ammonia.
The liquid level in the ammonia cooler of the synthesis unit is high. Large amount of ammonia is added; generally, a separator is installed on the main pipe before the refrigeration compressor inlet
The main reasons for liquid carrying in the ice machine are: 1. Excessively high or low liquid level in the synthetic ammonia cooler; 2. The cooling line of the ice machine being set too wide; 3. High liquid level in the ice machine separator; 4. Too rapid addition or removal of liquid. Treatment methods: 1. Control the liquid level of the ammonia cooler properly. 2. Reduce the cooling flow rate of the chiller and open the anti-surge valve to increase the inlet temperature so that the liquid ammonia vaporizes. 3. Control the liquid level of the separator properly. 4. Do not make changes to the flow rate too quickly
The main reasons for liquid carrying in the chiller are: 1. Excessively high liquid level in the ammonia synthesis cooler, along with an excessive amount of ammonia added. 2. The liquid level in the ammonia cooler at the copper washing station is too high, resulting in an excessive amount of ammonia being added. 3. The pressure of gaseous ammonia fluctuates greatly, with too rapid addition of ammonia
The liquid level in the ammonia cooler is the main cause; another factor is a sudden increase in the load on the ammonia cooler. This often happens during startup, when the load is increased rapidly – such rapid loading can cause the liquid ammonia to vaporize quickly, leading to gas-liquid entrainment. As a result, the liquid ends up entering the ice maker. If there is a separator at the inlet, this situation can be mitigated to some extent; but if the liquid gets directly into the ice maker, the consequences can be severe.
The chiller is running with liquid in it, and the temperature control of the ammonia cooler is set too low； The liquid level control of the ammonia cooler is set too high ； The liquid level control of the gas-liquid separator at the return air main is set high.