The concentration of methyl diethanolamine and production relationships
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This post was last edited by Qianxiafeng on 2010-5-17 23:34. What effects will a methyldiethanolamine concentration of 21% have on production? Recently, lean liquid was fed in, causing the concentration to be diluted to 21%. Moreover, the regeneration tower has been unstable, with frequent flooding!
The concentration of methyl diethanolamine cannot be determined in a general manner; each installation should set the concentration based on its own operational conditions. The 21% concentration you are using may be appropriate for other installations, or it might be too high or too low. If it’s just dilution with water, there’s no major issue; simply add pure amine solution in appropriate amounts. But the tower surge has no direct connection with concentration changes; look for other reasons that affect tower operation.
The concentration of methyl diethanolamine is normally around 30%, but there are also cases with lower concentrations (such as around 20%), and the highest concentration can reach 50%. The tower flooding mentioned by the poster doesn’t seem to be related to concentration; it’s more likely that foaming in the amine solution system caused the tower flooding. Therefore, the cause of the bubbling should be identified first, and then targeted measures should be formulated to address it.
It has an impact. First, energy consumption increases; second, the excessive load on the regenerated vapor can cause tower flooding. It is recommended to remove some of the solution and then add pure solvent to adjust the concentration. The solution removed can be used as make-up water.
The regeneration tower is unstable and often experiences overpressure! This is caused by amine solution foaming; we encounter it frequently. Solution: Add some fresh amine solution and incorporate an antifoaming agent. It can basically be eliminated. The key is still the quality of the amine solution.
This is definitely not due to the concentration. If the poster wants to increase the concentration of the amine solution, they can reduce the reflux rate and lower the pressure at the top of the tower! Tower flooding is caused by improper operation or foaming; it’s necessary to improve the filtration of the amine solution and maintain stable operation to avoid large fluctuations
There are various reasons for foam formation in amine solutions, and the causes should be investigated from the following aspects: 1. The content of mechanical impurities in the amine solution; 2. Whether the amine solution contains oil. After the amine liquid system in our old plant was put into operation, foaming occurred for three years; it was only after addressing issues such as filtration and the use of defoamers that the problem was partially resolved. When the new plant was put into operation, the amine liquid system in the entire plant was circulated for 1 month, and no foaming has occurred since then.