What are the reasons for the reduced heat exchange efficiency of ammonia coolers and how to address them?
Thread Content
Recently, the heat exchange efficiency of the ammonia cooler has been poor. During the major maintenance period, the ammonia cooler was opened for inspection, and no problems were found. Could everyone help analyze the reasons for the decline in its heat exchange efficiency and suggest ways to address it?
Is there any non-condensable gas? Release some of it to see what happens. We encountered this issue once as well, but it’s necessary to conduct a thorough analysis for your case!
The reasons for the decreased heat exchange efficiency of the ammonia cooler are as follows: 1. Whether the ammonia evaporation pressure meets the required standard； 2. Is the liquid level control appropriate? It should not be too high or too low ； 3. The presence of oil in ammonia affects the heat exchange efficiency ；
Some ammonia coolers also require drainage.
1. Oil should be drained regularly to prevent oil contamination from affecting heat exchange. 2. An excessively high liquid level of ammonia coolant, which results in less evaporation space, can also have an adverse effect. 3. Excessively high pressure of gaseous ammonia
The heat exchange efficiency of our plant’s ammonia coolers is poor. During the major maintenance, the ammonia coolers were opened for inspection, but no problems were found; this is because the temperature of the ammonia coolers had risen to normal levels during maintenance, which is different from their operating conditions. It was ultimately found that there were small leakage points in the head, causing non-condensable gas in the ammonia cooler.
Oil, water, and gas can all reduce the efficiency of heat exchange in ammonia-based cooling systems. The liquid level should not be a problem; you should be able to detect it. Try draining and venting to see if that helps
The reasons for the reduced heat exchange efficiency of the heat exchanger are as follows: 1) Low amount of cooling water; 2) High temperature of the cooling water; 3) Impurities in the shell side blocking the heat exchanger tubes or causing scaling, which leads to a decrease in the heat exchange efficiency of the water cooler. 4) Impurities in the tube side get adsorbed on the tube wall, resulting in a reduced heat exchange efficiency. 5) Internal leakage in the heat exchanger leads to a decrease in heat exchange efficiency. 6) Failing to vent when the heat exchanger is put into use results in a reduced heat exchange efficiency.