What material is used for the amine solution storage tank used in solvent regeneration?
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What material is used for the amine solution storage tanks used in solvent regeneration? Our tanks are made of carbon steel, but they are suffering from severe corrosion at present. Are there any tanks that have an internal lining or are made of stainless steel?
They are basically all carbon steel without internal anti-corrosion treatment; I’ve never seen any made of stainless steel. I couldn’t find any papers on the corrosion of amine storage tanks on CNKI, which indicates that corrosion in this area is rare. Could you send me a few photos of the corrosion so I can see what caused it? Logically, it is a lean liquid storage tank, and with the low temperature, corrosion should not be severe. If corrosion is indeed significant, it is recommended to apply heavy-duty anti-corrosion coatings or glass flake coatings.
There are really no pictures. The top of my amine storage tank has corroded and become permeable. Also, when the tank was cleaned during maintenance, there was a thick layer on the pipe walls, probably some kind of rust
For corrosion perforations on the tank top, it is necessary to carefully determine whether it is external corrosion or internal corrosion. Ours suffers from severe external corrosion; due to the insulation in place, water tends to accumulate, leading to corrosion beneath that insulation layer. There is rust inside the tank; when it is opened, air is present as usual, and it seems thick in some areas, but actually it isn’t that thick. Let’s take a look at the tank inspection results.
I remember that the inside of our solvent storage tanks was sandblasted; it’s supposed to be a form of corrosion protection!
Could it be caused by high levels of H2S and CO2 in the regenerated amine solution?
The H2S and CO2 contents in the lean liquid are very low; most of them have already been separated into the acidic gas
The top of the amine liquid storage tank is equipped with an ammonia gas seal, which prevents the oxidation of the amine liquid and corrosion of the tank
It was written wrong above; it should be nitrogen sealing!
The concern is corrosion caused by poor regeneration; if regeneration is done properly, carbon steel will not suffer from corrosion. It might be better to contact someone to conduct a comprehensive analysis of the amine solution, which could help determine what is causing the corrosion. The imported desulfurization agent requires a full analysis of the amine solution twice a year.