Foaming in the sulfur solvent regeneration tower, tower flooding
Thread Content
Recently, the regeneration tower (float valve tray) has been experiencing flooding issues, which disrupt normal and stable operation. The symptoms include an increase in the pressure difference across the tower, a rapid drop in the liquid level within the tower; no foaming was observed during sampling, there were no fluctuations in steam flow, and the flash tank did not contain any hydrocarbons. I seek advice on how to resolve this problem. Thank you!
Let’s start with two questions: 1. The air can’t rise, and the liquid can’t descend. Think about why something like this might happen 2. Logically, all your indicators are usually within the normal range, so why did the situation you mentioned occur? Let’s talk about how we can avoid such situations in our daily work: 1. Many processes in the refining industry are continuous operations. Many parameters undergo qualitative changes as a result of cumulative small changes; the prerequisite for such qualitative changes is quantitative change. Have you noticed the hints that small changes among these parameters provide? 2. Leverage the characteristics of similar processes. Regarding solvent regeneration, it is generally a relatively clean cycle system; however, the solvent system can also easily introduce impurities, leading to the formation of thermally stable salts. As mentioned in point one, this results in a reduced heat exchange efficiency and an increased pressure difference across the filters. Have you noticed this? 3. It is recommended to thoroughly clean the inlet filters of the rich liquid pump, semi-poor liquid pump, pure poor liquid pump, and related heat exchangers first. (Be sure to pay attention to safety during cleaning, as the hydrogen sulfide level here is quite high.) ) 4. While removing impurities, it is recommended to analyze the solvent to determine whether there are any thermally stable salts; if so, there are relevant threads on the forum that can provide guidance.
Try adding an antifoaming agent first; sometimes it’s not foaming that makes it hard to tell.
Is it because too many thermally stable salts are formed, causing blockages in the tray columns and accumulation of liquid in those trays, preventing it from flowing downward and leading to a rapid drop in the liquid level of the column? Could reducing the temperature of the vapor returning from the bottom of the column help, as well as improving the purification of the solvent?
The same is true for our sulfur recovery amine solution regeneration tower: 1. Check the filter screens to see if they are dirty or contain impurities, which helps determine whether the solution is clean. 2. Add an antifoaming agent. 3. Increase the tower pressure by reducing steam usage appropriately, as long as this does not cause the exhaust gases to exceed regulatory limits. 4. If none of these measures work, the tower must be shut down for inspection and cleaning of the trays
If it’s a floating valve tray, that’s definitely the case. Unless the amine solution is particularly clean.
This post was last edited by StackBridge1209 on 2021-1-28 at 11:34. Was the problem solved? Have you found the reason? Please share it