"1.15 bar = 16.679339871 pound/square inch"
In the US, state boiler and pressure vessel codes will generally require ASME for vessels/ tanks over 15 psi.
Elsewhere in the world, that could vary and you'd need to confirm local requirements.
As you note, ASME does not address flat-bottom tanks where the bottom is supported by the foundation, rather than by its own rigidity.
If the vessel is small enough, you could still use a flat head or blind flange designed per the code.
Otherwise, consider a skirt or legs with formed bottom.

API-650 addresses tanks up to 2.5 psi.
API-620 addresses field-erected tanks up to 15 psi and is sometimes used for shop-fabricated tanks as well.
I'm not familiar with this application, so I can't say what's "usually" done.

Can you post pictures of the old tower ? ... Are any old plans available ?

Is there a PID available or other document showing temperatures as well as pressures ?

Can you provide details or pictures showing where it has failed ?

MJCronin
Sr. Process Engineer

Er. ali-gct-meca (Industrial),

The info that you are looking for is more than analysis of a PV .. If the only info. is the analysis of absorption tower with design pressure 1.15 bars , that will be probably the easiest part of the problem..In this case, with a hybrid approach, you may perform the design analysis as per ASME PV code for the upper portion and API -620 FOR the flat bottom..

However, process design ,the material selection, acid resistant lining, packing and supporting system ... and performance requirements..are more curucial

I will suggest you to look past info ( as built docs..) and get in touch with original licence provider and equipment supplier..

http://www.sulphuric-acid.com/techmanual/strong%20...

MJCRONIN,

Please find attached the required scketches

• https://files.engineering.com/getfile.aspx?folder=7e58fb6d-2992-4eac-a42d-c

That configuration would lend itself to an API-620 design. If possible, reduce the pressure to 15 psi and use API-620. Otherwise, add a bottom F&D head with skirt support. If there are no legal requirements to the contrary, you could design it as a non-code vessel using API-620 design and higher pressure than covered by API-620, but that is a less desirable procedure.

Thank you everyone, that was truly helpful

Better quality and better quantity information always gets you better answers ....

MJCronin
Sr. Process Engineer