How to solve the air accumulation problem in the shell side of high-pressure heat exchangers
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I’m seeking advice from experts. I have designed a heat exchanger with a double-pass shell side; the material enters the shell side through the upper pipe ports and exits through the lower pipe ports. The heat exchanger is placed horizontally. Since the heat exchanger is located at a high position, it seems prone to air accumulation in the shell side. An exhaust valve is already installed on the shell side, but since it is a high-pressure heat exchanger with very high temperatures, it is not advisable to open this exhaust valve casually. However, during actual operation, non-condensable gas should accumulate, affecting the heat transfer efficiency. I would like to ask everyone for advice on how to solve this problem.
You mean the circulating water can’t be delivered, right? We had the same problem; later we redirected the exhaust valve to the flare, and we turned it on for a few minutes when heat exchange was poor
That shell-side exhaust valve is manual, and it cannot be opened casually, as the temperature and pressure of the material in the shell side are very high – several dozen kilograms of pressure and over 200 degrees in temperature – which makes exhaustation a challenging task as well.
Such toxic, harmful, or high-temperature/high-pressure materials are drained or vented into a closed system, thereby ensuring safety and facilitating operation.
If that’s the case, a high-pressure buffer tank needs to be added
If not a large amount is discharged at once, it’s not necessary; discharge it gradually.
It is necessary to drive it in practice to figure out the situation of air accumulation and the frequency of discharge. Mainly because of the harsh operating conditions, it is risky to send people to the site to monitor and slowly release the gas, as improper handling could lead to leaks.
If the outlet pipeline of the heat exchanger leads upward, and the equipment it connects to is located above the inlet of the heat exchanger, it is possible to connect the exhaust valve of the heat exchanger to this outlet pipeline in order to release air regularly； If the outlet pipeline of the heat exchanger runs downward, can it be modified by first directing it upward to a height that is higher than that of the inlet pipeline, and then letting it go downward again? The exhaust valve of the heat exchanger can then be connected to the highest point of the outlet pipeline, allowing for regular exhaust of air.
What are the pressure and temperature of the material before and after heat exchange? Has the pressure at the exhaust outlet been measured? What is it?