What materials are used for the acid vapor stripping towers and the reboilers of the amine solution regeneration towers in various factories?

The tubes are all made of stainless steel. One set for amine liquid regeneration in the shell side is made of stainless steel, while the other set is made of composite material; for stripping, one unit is made of carbon steel and the other of stainless steel.

Which one is more useful? Some say that stainless steel cannot be used in environments with wet hydrogen sulfide

This post was last edited by ylb913 on 2015-8-27 at 20:46. Carbon steel tube bundles cannot be used in the reboilers of regeneration towers; we have been using stainless steel for that purpose for about 20 years now. The unit currently in use is from the expansion of the facility in 2001; initially, the shell side was made of carbon steel, but it was replaced with stainless steel in 2007 due to corrosion. Stainless steel is used in the regeneration tower; our factory’s design team said it wasn’t feasible, but in practice there are no problems with it. Including the return lines of the reboiler, we have been using stainless steel for 20 years now; using carbon steel elbows caused excessive erosion and thinning. For the tube bundles in wastewater reboilers, we used carbon steel 19 years ago; later on, aluminum-coated tubes were used, but those didn’t hold up either. Eventually, stainless steel was adopted, and it is certainly much better than carbon steel. However, the tube bundle of this reboiler does experience corrosion and leakage; the cause is difficult to determine, but it may be related to chloride ions. Since we operate two stripping towers in turn (each with its own reboiler), the accumulation of coke powder is very severe. The severe corrosion of the tube bundle in one of the heat exchangers likely occurred as a result of failure to clean away the coke powder after shutdown; when it was opened for maintenance after one or two years, so much coke powder had accumulated that the tube bundle could not even be removed. The overall stainless-steel reboiler currently in use is a heat exchanger that was reused in 2008 (taken from another unit that was no longer needed); the tube bundle of this heat exchanger has not leaked.

The acidic water stripping tower is made of stainless steel; the reboiler tube bundle in the regeneration tower is also made of stainless steel, while the shell is made of 20R material

The stripping towers are all made of stainless steel; the outer layer of the MDEA absorption tower is carbon steel, while the inner layer is stainless steel.

What is the corrosion margin of the shell? Is there leakage in the shell side?

The interiors of both the carbon dioxide absorption tower and the regeneration tower are made of stainless steel!

Got it, O(∩_∩)O Thank you