Exothermic work on condensate storage tanks 1

[Alirezaparsa]

Hello to everybody
If anybody can help me it will be great.Recently we noticed that we must store condensate instead of crude oil in our storage tanks, so we selected those of tanks that have the best sealing system.in order to achive the best efficiency of sealing system, we must take the necessary precautions against toxic substance release, fire and explosion that required the activities upon shell that accompanied by release of heat(Exothermic work for example welding and ...). There is a big problem and that is all of tanks are in service.
My question is what's kind of consideration and requirment we should take them into account. I really need experties with specialized knowledg or who has similar experiences to give me some advice.

 

[Dhurjati Sen]

The condensate you are referring to is hydro-carbon condensate or steam condensate?

I think it is the former.

Internal painting is an important criteria.

Secondary seals on the floating roof is another.

Number and size of breather valves and goose-necks need to be decided.

The steam coil connection needs to be dismantled.

There are many others, but the above are the most important.

DHURJATI SEN

 

[MJCronin]

Well, .... good luck on this massive tank rework

This sounds like there has been some kind of MBA/Project Management Institute executive proclamation... "Change all Crude Oil storage tanks to Condensate Storage !" .... Right Now !!!

"in order to achive the best efficiency of sealing system, we must take the necessary precautions against toxic substance release, fire and explosion that required the activities upon shell that accompanied by release of heat(Exothermic work for example welding and ...)"

I have never heard of a tank sealing system that will withstand fires and explosions .... Welding near tank vents and sealing systems has caused many spectacular refinery explosions.

I suggest that you hire an experienced tank consulting Engineer, pay him his fee.... and follow his recommendations.

Getting a bunch of differing opinions from old retired Geezers and mid-eastern newbies on eng-tips is not the way to go .... IMHO

I could request that you respect us .... keep us informed of what you learn...... but you are from a part of the world where there is no respect

So you will probably drop this important thread .....like a hot potato ....

MJCronin
Sr. Process Engineer

 

[LittleInch]

I don't understand what it is you're trying to weld onto the shell??

a few drawings or photos or sketches would help.

what sealing system are you talking about? floating roof seals??

But welding onto a working tank is a bad idea for lots of reasons. Why is this being done?

You have the potential for a large vapour cloud or release of vapour from the tank and also the liquid will very rapidly cool any welding resulting in poor weld quality and potentially cracking the welds.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.