L/D Ratio of storage tank 1

[MHRG]

What is the significance of Choosing optimum L/D Ratio in Atmospheric storage tanks.?

As a normal practice the L/D ratio of atmospheric storage tank is considered within the limit of 0.5 to 1.1.
However, it is noticed that for some tanks it doesn't follow this limit. For example, fresh Amine storage tank.
Is there any fixed figure or whether it is optimized considering the plot plan, area available,wind load,civil work etc.

 

[MJCronin]

Hasib...

As is typical in most engineering design decisions......it depends.

IMHO, I do not believe that a simple answer is possible ...

This complex topic is typically referred to as the "Height to diameter" or "H/D" ratio. This important factor alone constitutes a strong reason to hire an experienced consultant tank design engineer.

The H/D tank design is affected by:

- Fixed or floating roof selection
- Soil conditions and foundation costs and foundation design selection
- Seismic conditions and allowable contents "slosh" under a seismic event
- Maximum design pressure
- Desired vapor space volume and tank venting requirements
- Minimum Fire protection distance requirements for combustible and flammable liquids
- Energy usage for tanks that are insulated and must be kept hot

- and other factors ....

http://www.eng-tips.com/viewthread.cfm?qid=277972

https://www.aij.or.jp/jpn/databox/2011/storagetanks2010edition.pdf

Tell us more about the tank that you are designing ...

MJCronin
Sr. Process Engineer

 

[MJCronin]

This question would be better answered in the "Storage Tank Engineering" Forum ....

MJCronin
Sr. Process Engineer

 

[LittleInch]

Define "atmospheric storage tank" please.

Do you mean vertical cylindrical tanks or horizontal cylindrical tanks? (L/D implies horizontal "bullet" like tanks....)

What sort of volume / size are you looking at?

If you have the space, most vertical cylindrical tanks are bigger diameter than height.

however if you are squeezed for room then you can get around 2 for height / diameter, but generally only for fairly small tanks

Optimum between foundation / civil costs, steel costs and other issues (e.g. seismic, wind, snow, rain, fixed roof, floating roof etc will all vary by fluid contents, sites, ground conditions, space.

That's why design engineers exist - to design!

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

 

[bimr]

Economical tank fabrication.

 

[MHRG]

Thank you Every one, all response where informative.
I realise that, In main case "bimr" is on the money .
"Economical Tank fabrication", ie. all other tanks are site fabricated while these tanks are shop fabricated which makes the deference.

 

[MJCronin]

You are welcome MHRG, you are welcome ....

And thank you for reminding us why senior engineers eventually become despondent and abandon these fora ....

MJCronin
Sr. Process Engineer

 

[MHRG]

I didn't mean to remind anything MJCronin. Apologize if you felt anything bad from me.
All the responses were 100% useful.