Amine Service Exchanger Tube Spec 1

[RRE]

What spec do you recommend for heat exchanger tubes in amine service? Do you have shared learnings around the use of seamless CS, welded (ERW = electric resistance welded) CS vs SS tubes in amine service?

What has been your experience (if any) with ERW CS failures in amines?

What do you recommend in amine exchangers, such as L/R, overhead condensers, or lean amine coolers??

Do you differentiate with the type of amine used?

 

[kclim]

Carbon steels can be susceptible to amine SCC, although this is quite rare

see

http://www.hghouston.com/case020.html

Furthermore, it may be possible for the amine to breakdown at higher temperatures, with acidic byproducts causing the corrosion of carbon steel - this depends on your conditions.

Stainless steel would be expected to perform better, but this depends on the impurities present (chlorides for instance are notorious for causing SCC in SS).

As far as the welding is concerned, I'd avoid it where possible. The welds present another site for impurities to deposit out, furhter exacerbating corrosion (differential aeration).

 

[EdStainless]

The breakdown products of amines will generally eat CS tubing quickly. There are Fe complexes formed with most amines.
There are differences in amines, but the biggest problem is variation in the trace contaminates.
Usually these solutions are caustic.
For low temp and clean systems 316L seems to work OK.
For higher temp 310S has been used.
For the most severe service alloys like 26-1(EBrite) have been used since they cannot stress crack in this environment.

You don't want high Ni alloys since htere are also Ni complexes that form with amines.

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Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm