leak test for ammonia-containing vessels 1

[YuJie_PV]

Hello all,
i have a vessel to be fabricated. it is utilized to contain ammonia. i originally mandate leak test, but my colleague argues it is "overdesign", unnecessary.
but i think ammonia leakage during service is harmful, shall i mandate leak test of the vessel during construction? please comment.
Thanks.

 

[MJCronin]

As is typical, we do not have enough information to provide even the most general of answers to your vague question:

My comments and questions:

1) Is this vessel of all-welded construction built to some nationally recognized code ?.... Provide details

2) Is the vessel to be pressure/hydro tested after fabrication ?.... What are the max operating/test pressures ?

3) Does the vessel have gaskets that are considered part of the design ? (This excludes gaskets at piping nozzles)

4) You consider ammonia leakage "harmful" ?.... No real surprise there ... I would use the descriptor "deadly"

5) All ammonia storage facilities (if that is what this is, we just don't know) have some fugitive emmisions. Anhydrous Ammonia Storage (if that is what is being contained) typically involve horizontal pressure vessels supported above a concrete gaseous "containment". Access is forbiden to the tank containment. Ammonia detection is located within the containment. Anhydrous Ammonia is denser than air.

6) Let the long string of questions and answers begin !!!

MJCronin
Sr. Process Engineer

 

[0707]

Your vessel shall be submited to all tests required by its code of construction. Boiler and Pressure Vessel Regulations set out by the Government

 

[YuJie_PV]

MJCronin, thanks for your comments.

sorry for the vague statement, and here is my general clarification:

1) Is this vessel of all-welded construction built to some nationally recognized code ?.... Provide details
reply: yes, it is welded construction per ASME VIII-1.

2) Is the vessel to be pressure/hydro tested after fabrication ?.... What are the max operating/test pressures ?

reply: the vessel will be pressure tested after fabrication. Max.operating pressure: around 0.05MPa.


3) Does the vessel have gaskets that are considered part of the design ? (This excludes gaskets at piping nozzles)

reply: as for gasket, there is gasket placed for manhole and spare nozzle。 No other gasket.

4) You consider ammonia leakage "harmful" ?.... No real surprise there ... I would use the descriptor "deadly"

reply: yes, the word "harmful" is not accurate, and sorry for my english.


5) All ammonia storage facilities (if that is what this is, we just don't know) have some fugitive emmisions. Anhydrous Ammonia Storage (if that is what is being contained) typically involve horizontal pressure vessels supported above a concrete gaseous "containment". Access is forbiden to the tank containment. Ammonia detection is located within the containment. Anhydrous Ammonia is denser than air.

reply: the vessel is not ultilized to store ammonia, but it is an ammonia dosing vessel, which finally support boiler system.

Thanks so much.

 

[r6155]

ASME VIII Div 1 is for 0,103 Mpa (15 psi) or more.

Regards