Impending tank failure before replacement can be fabricated

[southernyank]

I have a slurry tank made of carbon steel and lined with rubber. The rubber has begun to fail and a replacement has been order made of monel.

We are counting on the failure of the tank due to the extreme conditions (hot salt and caustic solution). In order to keep production going I need to come up with an alternative method (rental tank or otherwise) if the tank should/does fail. Because of the high pH, I'm having trouble finding a rental company that would help us limp along until the replacement can be delivered.

Any ideas on how to keep up?

Thanks in advance.

 

[StoneCold]

southernyank
How many gallons of material do you need to hold?
Think hard about it as it may be significantly less than you are holding right now.
No one wants to rent you something you are going to tear up. What about a used tank? A thick carbon steel or a stainless tank? Will disolved metals in your solution hurt anything?
How hot is it? Could you get away with an HDPE or XLPE tank?

If you answer these questions maybe we can help.

Regards
StoneCold

 

[bimr]

You comments do not make a lot of sense.

Steel tanks (nonbolter) generally do not fail in a catastrophic manner as plastic tanks do. The failure of steel tanks tend to be long term and problems are first noticed when leaking occurs.

Steel tanks are commonly used to store hot caustic as well.

If you tank is leaking, you can weld a patch onto the area that is leaking. You can also have the tank relined or lining repaired. The patch should hold until you have time to procure a new tank.

 

[lastone]

You could look into renting a stainless truck trailer. I've used one before to feed acid into my Unit for a short duration temporary facility. I'm giving out this option with the assumption that a thorough MOC would be done and followed. You would have to think in detail about containment, siting, operator access, temporary hoses, materials, procedures, training, etc...

 

[MikeHalloran]

Maybe you could adapt a propane tank that has exceeded its allowable lifetime.



Mike Halloran
Pembroke Pines, FL, USA

 

[dalcazar]

No company that sells tanks is going to rent you one (I used to work at one), and if you call saying you need an emergency replacement and mention the cause, everyone is going to turn you down for a rental.

I like lastone's idea of using a trailer mounted stainless steel tank. it's about the easiest way to get one delivered and the metal should be able to stand up to your solution. But again, I find it hard to imagine anyone renting you one.

plastic tanks are pretty cheap compared to steel (the final price, steel tanks are in themselves cheaper but need to be lined), the 5000 gallon range tanks being the cheapest, and you might get away with one for the time being.

The following link is a guide to chemical resistance of HDPE and XLPE in the face of different compounds. polyetylene stands up very well to alkaline conditions as long as the compound isn't organic.

http://www.rotonics.com/tanks/technical information/CHEMICALRESISTANT.pdf

you talk about a slurry, what is the density? poly tanks cannot hold liquids with densities above 24 lb/gal. Standard tanks hold only 8 lb/gal. you might just want to call the company to see if the tanks will hold up, they can give you a price estimate and tell you if you need to go with linear or crosslink PE.

http://www.rotonics.com

they're pretty helpful.

hope this helps

 

[southernyank]

Thank you all for your comments and info, it's been very helpful.

Just some follow-up info on why I was having the problem. The tank is around 20,000 gal and is undersized as it is. It's actually a SS 304L tank and I've been warned that steel will fail in chloride conditions at temps above 75 C.

Since my post I've done numerous temp profiles on the tank and (even without a lot of the rubber lining) it stays below 65 C.

With the hope that my worries were a bit extreme for the situation, combined with the info that you've all supplied, I feel much better about my situation.

Thanks again and Happy Holidays!