Why can water be discharged from the factory’s air ducts?
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Recently, while connecting temporary pipelines to use the plant air from the utility station, I noticed a large amount of water being discharged from the plant air pipeline – it took over ten minutes for all the water to be drained. This was quite puzzling, as plant air is supposed to be dry and clean air that has been compressed to an appropriate pressure before being fed into the utility network (which should therefore be dry and clean). So where did the water in the network come from? Please discuss!
:Handshake: The pneumatic network is capable of removing water, and the amount removed is not small. I think the search should be carried out from the following aspects: 1. Check whether the silica gel in the regenerative dryer has become ineffective. 2. If the adsorbent has a poor adsorption capacity for air, condensation water is likely to form as a result of phase changes. 3. It is possible to check whether there are any points where the system is connected to the plant’s air distribution network that are also in contact with water-based media, such as the air used for cooling air flushing, as well as the air required for the regeneration of desulfurization and decarburization units as well as copper washing filters. :handshake :handshake
Is it a dead end of the pipe? Is it because of the initial driving process, with water not being thoroughly purged after pressure testing? :(
Agree with what was said above; a few additional points: 1. After waiting for a while, the flow can be completely drained, which essentially indicates that there are no process pipelines connected in series； 2. The dryer may not be effective, resulting in water accumulation somewhere in the process air system ； 3. The instrument air system needs to be checked, especially during winter, as this could lead to the paralysis of the automatic control system ； 4. It is recommended to keep the valve at the bottom of the buffer tank within the boundary area slightly open to help drain some of the accumulated water.
It is recommended to add a blind pipe at the lower end, and install a drainage valve at the end of the blind pipe for regular inspection and maintenance.
In winter, temperatures are low, the air density and humidity are high; as a result, the dryer in air compressors is under increased load, which causes water to be present in the compressed air. It is recommended to enhance dehydration in the air tanks to prevent freezing and ensure the safety of the equipment.
There are numerous variations in the production process, requiring extensive analysis
It is also not possible to remove all the moisture from the air through drying and compression; the air supplied by the compressor contains heat, and after being transferred through pipes and cooled, condensation occurs within those pipes. As a result, compressed air contains moisture. When compressed air is in use, once heat transfer due to air flow ceases, no more condensation takes place, and the water becomes invisible.
Air contains a certain amount of water vapor naturally. When the air is compressed and the pressure exceeds the saturated vapor pressure of the air, the water vapor condenses. This occurs more easily in winter when temperatures are low; therefore, water is discharged at the lower points. The solution is to install a discharge valve at the low point for regular discharge.
Water is discharged, possibly because the air contains moisture. Even after compression and drainage, water will still remain inside, so it needs to be removed. Also, during the initial hydrotesting of the pipelines in the installation, more water may remain. Although purging is carried out, there are still some areas where water can stay trapped. After some time passes and the water settles, it will all come out
Water is inevitable; it’s just a matter of how much. Install a drain trap in the air tank, which can automatically discharge water and prevent adverse consequences.
It’s not a new factory; it’s an old facility that has been in operation for many years! It’s cold now, so it’s necessary to drain it regularly every day to prevent the pipes from freezing!
The problem mentioned by the poster is quite common during refinery operations in winter, and it represents a significant hazard that affects safe production during this period; therefore, it is given priority in winter production plans for inspection and prevention. Our company uses cold dryer technology for deep dehydration, and the results are good. However, due to the long length of the pipeline network, it is still necessary to regularly check the drainage of the liquid separation tanks in the equipment area to ensure the safety of the instruments.
Water accumulation in compressed air pipelines is also a common issue, mainly due to inadequate drying. It becomes more noticeable when the temperature drops. Freezing of compressed air pipelines in winter has also occurred, so extra attention should be paid.
Additional information for the second floor: Check whether there are any faults with the programs and instruments of the drying system
It’s cold now, and it’s normal for water to flow from the pipes. Compressed air is usually at a relatively high temperature, and simple drying cannot remove the moisture contained within it. When such PA is sent out into an environment with lower temperatures, the moisture inside comes out – which is quite normal.
I’m not sure what type of drying device the poster is using for compressed air. If it’s a cold dryer, it might be that the cooling temperature is too low or that the separation efficiency is poor. If an adsorption dryer is being used, it’s possible that the desiccant has become inactive. This situation is very dangerous; it’s essential to identify and resolve the issue as soon as possible to prevent valves from getting stuck
The key issue with water in factory air is the possibility that the desiccant has lost its effectiveness. In factories in the north, the air is designed to have a saturated vapor pressure of -40 degrees; therefore, if the ambient temperature does not drop below 40 degrees, it’s a problem with the desiccant, and replacing it solves the issue.
One thing is that the air itself contains moisture; another issue could be a problem with your dryer or an excessive load on it
It is generally required that the dew point of compressed air be below -20 degrees. Our factory also encounters this issue frequently; over time, air condensation occurs, so it is necessary to check the drainage system regularly. It is generally not instrument air; it does not pass through a heatless regeneration unit.
1. My work experience: I removed half a tank of water from the air buffer tank; the reason was a malfunction in the water removal device. 2. In our factory’s air compression process, there is also a water removal device, and the air is dried to a temperature of -35°C. The situation is good, for your reference. 3. When air does not circulate, moisture tends to condense and accumulate. If you are interested, take a look at the three-way valve before it during the annual maintenance – it can be useful information! 4. The quality of the air compressor is also quite important; water-cooled compressors perform slightly better than air-cooled ones (based on experience)