Issues with argon fraction fluctuations?
Thread Content
Here, we have 30,000 units of air separation capacity. Recently, there has been a high demand for cooling in the morning, which leads to a large amount of liquid being produced. Starting around 1 p.m., the argon fraction begins to increase, while the level of the main cooling liquid drops to around 2200. Efforts are made to keep this level around 2200; the argon fraction remains at 8 to 9 points, and the liquid oxygen output from the lower column is around 700. In the worst cases, the level of the main cooling liquid dropped as low as 1400. With all other conditions unchanged, I wonder if it’s the ambient temperature affecting it? Or there might be something else. I wonder if anyone has experienced this! Let’s all share
In the morning, the air humidity usually drops sharply compared to the evening, and the temperature rises; check whether there are significant changes in the water temperature of the circulation system
The circulating water temperature is normally 25 degrees in the morning and 30 degrees in the afternoon, but this does not affect the main cooling system. In the lower part of Tower 1 for crude argon, the liquid level has dropped from 2700 to 2200, from 730 to 620, and from 1700 to 850 – a significant decrease. This is due to an increase in expansion volume, which results in less cooling capacity from high-pressure throttling. The venting volume from Tower 1 for crude argon has been increased by 50 units until it is at full capacity, in order to prevent nitrogen buildup. So, where does all that cooling capacity go? Don’t you quite understand it?
I have a similar situation here, but the fluctuations on my end aren’t as severe as yours. The main fluctuations occur in the argon fraction here; I suggest you monitor the changes in the temperature of the material entering the tower – at least it has had a certain effect in my case
I don’t know exactly how much time separates the morning and afternoon you’re talking about. If it’s one or two hours, then we need to analyze whether there’s a connection between them. Such large changes in the three liquid levels indicate insufficient cooling capacity, assuming that the liquid level measurements are accurate. The ambient temperature shouldn’t have such a significant impact. You say that the expansion amount has increased, which results in less cooling capacity from the high-pressure throttling mechanism; so how is the temperature difference on the hot side maintained? Also, when liquid is drawn out with force, does the pressure of the booster remain unchanged? As for the changes in the argon fraction, they are certainly caused by fluctuations in either the main column or the argon column; what you need to do is monitor each pressure and temperature point, observe the changes, and then analyze them.
I think we should go to the site to check the actual opening degree of the liquid discharge valve, especially for liquid oxygen.
The temperatures are high in summer, so it’s necessary to adjust the operating conditions in the early morning and evening. You use external compression, right? The air volume at noon is clearly insufficient; reducing the load will solve this issue