Nitrogen compressor safe or \"unsafe\"”~~
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This post was last edited by Ameba on 2016-5-16 at 12:06. A few days ago, I heard that a nitrogen compressor in a company experienced a combustion explosion (in an air separation unit). Upon analysis, the cause of the accident was the intrusion of oxygen into the nitrogen pipeline~~ It is likely that oil was present, and combined with the heat generated during compression, this led to the combustion explosion. Those who work in air separation operations might think that nitrogen compressors are not a major concern and therefore don’t pay enough attention to them, but accidents often happen unexpectedly~~ I’m posting this to urge everyone to take it as a warning. Of course, anyone who encounters unexpected failures or accidents can also share them here for discussion~~
There is no absolute safety; last year, there was a heavy downpour in our area, and water entered the low-pressure control valve, almost causing high pressure to penetrate into the low pressure system. Fortunately, the inspector noticed the abnormality in the magnetic level indicator on site, contacted the operator on site, manually closed the manual valve to prevent further rise in the liquid level, and then took manual control. After checking, both control valves failed at that time~~~
For important valves, first, interlocks must be installed; second, they need to be calibrated regularly; third, inspections should be carried out after shutdown. . . We had something similar: water entered the air stream, and it almost backflowed into the compressor. . .
Is it possible to install an online oxygen analysis cabinet? At what level should an alarm be triggered? Our fans come equipped with such a device by default
Nitrogen in air separation is highly pure and very safe. . . I don’t know the main cause of the incident. . . Pure gas was introduced without proper purging. There is still another pipe leaking in. . . Continuing to pay attention. . .
How does oxygen get into the nitrogen pipeline?
The possibility of using one machine for two purposes is low, so the chance of pipes leaking in is also ruled out~~ It seems that it’s due to the introduction of purified gas, along with the need to completely displace it~~
In some cases, nitrogen is used to start up the oxygen compressor; in other words, the inlet pipeline is temporarily shared with the nitrogen compressor. Could it be that a faulty valve or failure to switch the blind plate led to oxygen getting into the inlet of the nitrogen compressor? Wild thoughts:D:D:D:D
The key here is a nitrogen compressor. . .
This post was last edited by Wang Shui on 2016-5-15 at 14:58. It seems there is a problem with the pipeline design; another possibility is that an air separation unit failure caused the system to shut down – the oxygen compressor stopped working while the nitrogen compressor continued to operate, resulting in oxygen-rich air being drawn in； Finally, it is also possible for sealing gas to mix with oxygen, especially at the location of the crude argon pump where mixing is most likely to occur. When the crude argon pump starts, the oxygen content at the bottom of the two towers is very high. If, during design, liquid vaporization after the pump and instrument air are used together as the sealing gas for the pump, it happens that this same instrument air is also used as the sealing gas for the oxygen compressor and nitrogen compressor.
Abnormal parking – that’s actually a good idea. . .