What is a “nitrogen plug”?”
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What is a “nitrogen plug” in an air separation unit? ? I’d like to ask further: how can one eliminate the \"nitrogen plug\"? This post was last edited by jh56565656 on 2008-2-19 19:47.]
Generally, argon fractions have low oxygen content and relatively high nitrogen content (the sum of oxygen, argon, and nitrogen is 100%)； If the nitrogen content in the argon fraction is too high, it not only reduces the purity of the crude argon but also causes the temperature difference in the crude argon condenser to decrease, or even bring it to zero (resulting in a \"nitrogen plug\"); in such cases, the crude argon column stops functioning ； The upward air flow velocity decreases. Furthermore, excessive nitrogen in crude argon will make it difficult to produce pure argon. “The occurrence of the \"nitrogen plug\" condition is due to a sudden decrease in the amount of air entering the tower during the pressure increase phase of the molecular sieve adsorber, along with a sharp rise in the nitrogen content in the argon fraction. The measures to address this type of \"nitrogen blockage\" fault generally include: ① Hierarchical control of the pressure equalizing valve, that is, during the 10–12 minutes of the pressure increase phase, the pressure equalizing valve is opened slowly until it is fully open, thereby achieving a balanced gas supply ； ② If the guide vanes of the air turbine compressor are equipped with the function to receive signals, they can be automatically opened earlier, 2 to 3 minutes before the molecular sieve adsorber enters the pressure-raising phase, thereby increasing the exhaust volume and minimizing the range of air volume fluctuations caused by that pressure-raising phase.
What was said upstairs is more or less correct, but one additional point is that by taking into account the liquefaction temperatures of nitrogen, oxygen, and argon, as well as the operational characteristics of the argon system, it’s easy to understand the origin of the \"nitrogen plug\" phenomenon; in short, nitrogen disrupts the conditions under which argon is distilled
Understood, thank you very much! ! ! ! ! ! ! !
Dear expert, what are distillation for argon removal in air separation and hydrogen-based argon removal?
Did it say above that argon is produced by full distillation and by hydrogenation? One method uses distillation, while the other uses hydrogenation to remove the oxygen component from argon.
How long is the typical service life of catalysts used for hydrogenation to produce argon?