TET heating issue

:(Come on, is no one answering?)

Have you actually calculated it using simulation software?

1. First, it is recommended to check whether the strainer is functioning properly and whether there is any non-condensable gas remaining in the reboiler, as this can lead to a decrease in heating efficiency； 2. Inspect the material to check for excessive accumulation of polymers or deposition of metal impurities.

Wasn’t the same amount or more vapor used unable to achieve the previous results? How long has your tower been in use? Your tower top pressure should be sufficient, right? If the top pressure can be achieved, then check the heat exchange system and the material composition.

Reply to 3# lgl102110: It’s not a matter of whether it can be achieved or not; usually, temperatures can be reached with 800 cubic meters, or even 700 cubic meters, but now even 1000 cubic meters aren’t enough to achieve that temperature.

Reply to 4# wangli115: The reason for using a steam trap at first was that the normal function of that trap for draining water was not adequate (the drainage speed was too slow). At that time, the steam flow could not be increased, and neither adjusting the valves nor opening the bypass to 100% solved the problem. Currently, without replacing the steam trap, the fluid is directly discharged through the vent, but the temperature still doesn’t reach the desired level – in fact, it’s even lower. That bottom stream TET is fresh TET; by the way, the TET that enters the tower contains HCL. The distillation tower is primarily used for distilling HCL – with HCL at the top of the tower and TET at the bottom. There shouldn’t be any impact from the components, right? After all, it was possible to level up directly before! Speaking of impurities, how much can impurities affect the temperature at the bottom of the tower?

Reply to 5# Yangguangmei: The pressures at the top of the tower can be achieved; the bottom of the tower required replacement due to leaks in the welds of the lower flange. But since the reactor vessel was replaced, the temperature has not been able to rise up to the desired level since the system was put back into operation. As for the composition of the material, it is fresh TET; some colleagues suggest that the purity of the TET is too high, but I think this reason doesn’t seem plausible. The feed we use consists of TET containing HCL, with very little amount of TCS, DCS, and the like present. Regarding heat exchange, my question is: if the steam is simply vented, wouldn’t that result in a reduced utilization rate of the steam, as its latent heat isn’t being utilized? Even though currently 900 cubic meters, or even 1,000 cubic meters, of steam are being used, it’s not certain that this will achieve the same results as when 7,800 cubic meters of steam were used before

This post was last edited by wangli115 on 2011-9-28 at 15:28. Reply to 7# zw1902: As you mentioned before, is this distillation tower used for hydrogen chloride separation? If it’s a hydrogen chloride stripping tower, if the temperature at the bottom of the tower cannot be increased, it might be due to delayed removal of hydrogen chloride. Has the temperature at the top of the tower also risen significantly? Is the liquid level in the reflux tank remaining high all the time?

I have a gentle question: what is TET?

Reply 1# zw1902: Could it be that the tower has been flooded? Personally, I think that in the case of a tower flooding issue, the liquid level in the tower bottom is too high, which prevents the vapor from the reboiler from rising. Since this vapor cannot rise, the steam pressure at the tower bottom remains low, and as a result, the temperature at the bottom of the tower also doesn’t increase