HELP me understand.....Shell and Tube Single phase heat exchangers

Good Evening Group. Please educate me....
Glycol and ammonia shell and tube heat exchangers.

First question: I am accustom to seeing the tubes inspected in the refining industry and chemical manufacturing plants. In ammonia refrigeration systems are you guys/gals looking inside from time to time to see the condition of the tubes - to prevent leaks?

Second questions: When A leak happens - can you get a backfeed of ammonia into the glycol system?

Third Question: What would be the symptoms of a leak in the tube?

I visit here every now and then to educate myself and not feel intimidated to ask the questions that I need to understand...I thank-you for helping me on this one....

Seaturtle....

Hello everybody I am working on a project which is basically upon S&T heat exchangers
I would really appreciate some guidance.
Thanks.

Hi, briankeating :)

Welcome to RE forums.

Quote:

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Originally Posted by briankeating

Hello everybody I am working on a project which is basically upon S&T heat exchangers
I would really appreciate some guidance.
Thanks.

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What you like to know about S&T heat exchangers?

Best regards, Josip :)

Hi, bsh3239 :)

Quote:

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Originally Posted by bsh3239

Good Evening Group. Please educate me....
Glycol and ammonia shell and tube heat exchangers.

First question: I am accustom to seeing the tubes inspected in the refining industry and chemical manufacturing plants. In ammonia refrigeration systems are you guys/gals looking inside from time to time to see the condition of the tubes - to prevent leaks?

Second questions: When A leak happens - can you get a backfeed of ammonia into the glycol system?

Third Question: What would be the symptoms of a leak in the tube?

I visit here every now and then to educate myself and not feel intimidated to ask the questions that I need to understand...I thank-you for helping me on this one....

Seaturtle....

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Petrochemical industry is a little bit different ... old fashioned construction with flanged joints for inspection and with manhole .... of course also with enough resources for yearly inspection of complete plant

Standard refrigeration plants is not the same construction .... heat exchangers mostly are of welded type without manhole ... much cheaper, but still enough reliable to last quite a long time without any leaks .... good inhibitors in glycol and pure ammonia without water and you can run it for 20+ years

In case of internal leak the flow depends on working pressure ... glycol can flow into ammonia side or vice versa ....

Symptoms ... the best is to install ammonia sensors into glycol pipes to give you alarm in case of leak or if you have an open to air glycol system you will smell it ... very soon

in vice versa when glycol is entering into ammonia side you must notice that your glycol level is lover and your ammonia level is higher ... not sure, but there must be available some indicators for glycol in ammonia side too ...

anyhow every few years 3-5 is necessary to empty exchanger (glycol side) and check for leak ... with ammonia little above normal working pressure ... if you have a leak you will find it ...unfortunately;) in case of welded type is almost impossible to repair it ...

Of course if you have S&T heat exchanger with covers on glycol side everything is easier ... discharge glycol and make a leak test with ammonia again ... no smell no leaks ..

Hope this will be of some help to you. Maybe some other members will come with some better solutions and suggestions.

Best regards, Josip :)