Can instrument air be provided by nitrogen?
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After a power outage, for safety reasons, some instruments need to be controlled using pressurized air. To reduce the need for pressure storage tanks and air compression stations, could liquid nitrogen from air separation be used, after being vaporized and pressure-regulated, as a substitute for air to power these instruments?
It should be possible, as long as nitrogen waste is avoided
As long as money isn’t a concern, nitrogen can be used to replace air. Using nitrogen is beneficial for both pipelines and pneumatic valves. Do you know if your nitrogen pressure can be guaranteed?
Using nitrogen is of course a good option, as it reduces unnecessary malfunctions – what a wonderful thing that is for instrument technicians. However, nitrogen is much more expensive than air, so factories generally prefer to use air.
Under special circumstances, it can be used, but the pressure must be equal to the air pressure!
1. The cost is too high； 2. Prevent suffocation
We have a cross-line from nitrogen to instrument air, which is used in emergency situations. But I think the most important question is one related to safety, especially regarding the provision of positive pressure ventilation for the equipment.
Yes, it is common to use nitrogen as a gas source for instruments in metallurgy, as nitrogen is the main by-product of the oxygen production process used in metallurgical smelting; its primary uses are for nitrogen sealing and supplying gas to instruments. This post was last edited by ZZD109 on 2009-4-7 19:39]
Of course, but be sure to prevent excessive air pressure from entering the N2 pipeline when the instrument air is restored – this is absolutely not allowed.
It can be used as long as there is no oil, dust, or water.
Nitrogen can certainly be used as an instrument gas source, but from an economic perspective, it is definitely not cost-effective. You can check the nitrogen price in your area and you’ll know.
We use nitrogen, and just make sure to ventilate enclosed spaces.
Could there be a problem with suffocation? Causing localized hypoxia
If one has the money, it is certainly possible to use N2 instead of air as instrument air. If it is used solely for instrument air purposes, there should be no issues related to suffocation. The problem of asphyxiation mainly arises when using N2 for purging and displacement; therefore, care must be taken during this process of purging and displacement.
That’s great. Nitrogen is clean, does not support combustion, and it doesn’t burn either. As long as you have enough nitrogen, it’s excellent. It’s ideal for use in places where things are flammable or explosive
Sure, but it’s much more expensive. Our company uses compressed air.:)
Argon is also an inert gas and is relatively safer, but some valves require a pressure of 5 kgf/cm2, which makes them too expensive.
It is highly recommended not to use nitrogen as the source of instrument air. There is a misconception that nitrogen is odorless, non-toxic, and harmless; however, it is precisely because of its odorlessness that people can suffocate when the nitrogen concentration is high, without even realizing it. A lesson! ! ! ! 1
As long as money isn’t a concern, nitrogen can be used to replace air. Using nitrogen is beneficial for both pipelines and pneumatic valves. Using nitrogen poses a serious safety risk; usually, after the plant stops operating, emergency repairs are carried out. Instrument air and plant air are part of the same system, so if the entire air network is filled with nitrogen, it becomes very dangerous.