plat heat exchanger

[Tamer123]

dear gus
why in LNG plants and other plant which use Amin solution to remove CO2 from gas, alwas the heat exchanger betwwen rich and lean amin is plat heat exchanger ?

 

[europipe]

Why not?
They are small and not so expensive,
easy to install

 

[joerd]

Plus you can get a close temperature approach, and the flow is truly countercurrent, so there is no issue with the temperature "cross", i.e. the outlet temperature of the lean solution is lower than the outlet temperature of the rich solution. You would probably need multiple shell&tube units to do the same service.

Cheers,
Joerd

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[Tamer123]

plat heat ex is hard to clean chemicaly and it is not easy to clean it mechanicaly because of it's reassembly also amine system is have many contaminate because it contact with gas which always not clean

 

[Zoobie]

I disagree with your last statement. I have had a lot of success with in-situ chemical cleaning of plate heat exchangers...it all depends on what is fouling it and what you clean it with. The same goes for other heat exchanger types. Reassembling a plate heat exchanger is very simple (once you have changed the gaskets). The equivalent mechanical cleaning of a shell & tube may involve pulling bundles...not always easy, especially in remote sites.

 

[Jason5000]

Always insist on a pair of 100% units when plate frames are to be used for critical exchangers. I've heard tell of some new units being built with only single plate exchangers; I wouldn't want to have to count on one make a full turnaround cycle.

I've had a reasonable amount of luck with chemical cleaning plate exchangers in place too, but there seems to be a point of diminishing return on chemical cleaning. After the second or third chemical cleaning the recovery of heat transfer is diminished and a mechanical cleaning becomes necessary, at least that's been my experience.

 

[deilam]

plate exchanger is good for clean service,it needs low space in compare to s&t exchangers,cheaper than s&t exchanger,in case of cleaning it is not hard ,if we follow vendor instruction it is very simple.

 

[dcasto]

Jason5000 is correct on having a 100% spare when using plate exchangers on rich lean amine service. At some point, its better to just pay the up front cost and get a Stainless Steel shell and tube, no fuss no muss.