Double Wall Tanks 1

[codeeng]

Could anyone recommend a tank vendor with experience in double wall API650 tanks (30 to 70m diameter). Project is located in Canada. Thanks in advance.

 

[IFRs]

JJ White, Matrix, Fisher, CBI, etc - any of the larger, reputable tank builders.

 

[MJCronin]

code...

30-70 meters is a pretty big tank.....

Why must containment be assured by an expensive double-walled tank ?

My experience with these type of tanks is that they are a good choice only where there is a limited footprint for the new tank.

Most of the US environmental requirements allow for a concrete or clay containment that can be much cheaper.

Has this been considered ?

-MJC

 

[codeeng]

Thanks MJC
I totally agree, its seems so stupid, but our client wants to know the cost delta and I'm struggling to find a vendor that could provide costs. I'm thinking 70 - 80% more. Would this sound about right?

 

[Elrae]

codeeng,

As previously stated, there are many major tank builders that can do this type of work. I would stick with large companies CBI, Matrix, ATV, PTC, and the like. If you are thinking that 70-80% additional is a good guide, I would disagree. There are a number of special difficulties with steel containment that need to be addressed.
1. Will the inner tank share the bottom with the outer tank?
2. Will fitting penetrate both shell walls? If so, how will differential expansion be handled?
3. How will the outer tank be roofed to eliminate rain accumulation or will it be left open with it's own draw-offs installed?
There are many questions like this to be answered during design and quote. Since the outer tank is larger than the inner tank, depending on the answers to these type of questions, you could have an additional cost of up to 150%.

Best of Luck

 

[MJCronin]

code..

I suggest that you contact some of the major fabricators and ask them about the biggest double-walled tank that they have ever constructed.

If it is smaller than the size that your client requires, I think that you should pursue drug testing for his spec writer......

An evaluation of the cost of a double walled tank of this diameter is moronic..

I have long recommended mandatory drug testing for all of our new clients

-MJC

 

[JoeTank]

codeeng
Is your reference to a double wall tank to a tank with a steel dike around it or a tank with a tightly fitted jacket?

Joe Tank

 

[codeeng]

More like a jacket but could be either to satisfy secondary containment. Apparently this is more common in Europe, not so much in Canada.

 

[JoeTank]

codeeng,
Thanks for clarification. I have never heard of a tank that large with a seconadry tight-wrap layer for leak detection. In addition to breaking new ground, the future maintenance of the tank woould be a nightmare.

The more practical approach would be to use a steel dike for secondary contaainment. Basically, it's just an open-top tank that surrounds the primary tank. The spacing between the walls is often often about 5ft, but will be governed by fire-fighting requirements (if its a flammable or combustible product)

Joe Tank