13 replies to this topic

[Hyper]

Dear All

I should calculate 3 type of storage tank;

• 1- Gasoline storage tank(capacity is 6000000 Litre)
• 2- Diesel storage tank(capacity is 6000000 Litre)
• 3- Heavy Fuel storage tank(capacity is 5000000 Litre)

i need to know thier dimension(hight,diameter) & tank type( fixed roof or cylendical, spherical,...).


Many Thanks,

M. Farhang

Edited by Mahmoud Farhang, 15 April 2012 - 09:01 AM.

[breizh]

To support your query related to unit conversion many ways :
1) google
2) Download from internet a software : Uconeer
For tank design
1) for the tank dimension let you consider this resource , document issued by Mr Montemayor.

Hope this helps
Breizh

Edited by breizh, 15 April 2012 - 05:57 AM.

[go-fish]

Mahmoud

For tank roof type, you should know the TVP at the max. storage temperature of the tank contents. Based on the local emission regulations, you have to decide on the roof type. For example as per United States EPA CFR 40 Part 60 Subpart Kb:-

• Tanks storing material with TVP’s of 5.2 kPa and less can be fixed roof tanks
• Tanks storing material with TPVs above 5.2 kPa but less than 76.6 kPa must be equipped with external or internal floating roofs or can be fixed roof tanks equipped with closed vent systems with vapor directed to a control device.
• Tanks storing material with TVPs above 76.6 kPa must be equipped with closed vent systems with vapor directed to a control device.
• Tanks storing material with TVPs near atmospheric pressure, should be either API 620 or ASME pressure vessels.

I anticipate heavy fuel oil and diesel to be fixed roof and gasoline to be floating roof type. But you should confirm after obtaining TVPs.

Tank height generally depends upon the soil load bearing capacity. You can obtain that from geotech data. Once you have the height you can work out the diameter based on the working volume. Remember there is a few meters in top and bottom which you need to allow as unused volumes. This is a preliminary way of calculating height and diameter, you have to match these with nominal sizes available from vendors. Generally, this part is handled by the static equipment group.

Hope this helps. I am not an expert in the area but this is what I follow. Comments from Seniors in this forum are welcome.

Edited by go-fish, 15 April 2012 - 05:52 AM.

[kkala]

-I have corrected true vapor pressure limit for fixed roof tanks in post 2 of http://www.cheresour...s-vapour-losses '> http://www.cheresour...s-vapour-losses , seeing that 5.2 kPa (0.75 psi) mentioned by go-fish makes sense. Mentioned web reference also contains other data probably useful.
-1 barrel = 42 US gal = 42*231 in₃ = 0.159 m3. Tanks of 6 MM barrel = 954000 m3 seem too large to me, I have heard of e.g. 100000 m3. It is useful to check capacity again.
-Tank height can be also dictated by available space or max height permitted by law in the specific area of location. Tanks of such high capacity are usually constructed with low height to diameter ratio (flat), this resulting in minimum capital cost (for a given capacity)

[Hyper]

first i want to thanking you.

Mr. Kkala is right, i made a mistake in capacities and i amend them.

i undersatabd from your replies that for gasoline i should consider a floating roof and for HF & diesle tank, a fixed roof.

but does gasoline tank need to any special insulation???(for prevent evapration of gasoline)

Also, i need an excel sheet for Designing of them in API 650?

Mr. Breizh sent me some excel(many thanks), but they are in US unit.
also if the file includes all calculation such as shell,wind girders,top angle, sesiemic,bukling,overturning, buoyancy,venting,... its really good.

thanks for all you that consider my elementary questions.
M.Farhang

[S.AHMAD]

i undersatabd from your replies that for gasoline i should consider a floating roof and for HF & diesle tank, a fixed roof.

but does gasoline tank need to any special insulation???(for prevent evapration of gasoline)

1. All high vapor pressure materials such as crude oils, gasoline, naphtha, condensate, are normally stored in floating roof tanks. In the past, only big tanks were stored in floating roof, however current trend is to store in floating roof regardless of size. The floating roof for small tanks normally of internal floating roof.
2. Insulation is not required.

Edited by S.AHMAD, 16 April 2012 - 04:35 AM.

[Hyper]

dear Ahamd

thanks

you mean i shall select internal floating roof tank for gasoline,diseil & heavy fuel storage tank.
but in post#3 i heard another things from Go-fish.



when we chose internal floating roof or external floating roof?
is it depended to tank size?

Hyper

Edited by Hyper, 16 April 2012 - 05:05 AM.

[S.AHMAD]

dear Ahamd thanks you mean i shall select internal floating roof tank for gasoline,diseil & heavy fuel storage tank. but in post#3 i heard another things from Go-fish. when we chose internal floating roof or external floating roof? is it depended to tank size? Hyper

1. Do you really understand the meaning of vapor pressure? and which products that have high vapor pressure? We do not really test the product for vapor pressure. The normal test id the Reid Vapor Pressure (RVP). Attached pdf file shows the relationship between TVP and RVP.
2. Please take note that products such as diesel and fuel oil are combustible BUT not flammable and very low vapor pressure. Therefore, floating roof tank is not required for these products. Generally, any products that is generating flammable vapor MUST be stored in either floating roof or inert-blanketing. Refer to post#3 for more specific requirements.
3. Internal floating roof tank is only for tank diameter of less than 45 m. This is in-house guideline not an international standards.

Attached Files

•  TVPvsRVP.pdf   285.69KB   800 downloads

[Vignesh S]

How can I decide Tank height with respect to the soil load bearing capacity?

Thanks
Vignesh.

[eastorca]

Dear Mr. kkala,

Thank you so much.
Following topics, your link has led me to standards which recommend tank type and its maximum allowable vapor pressure of storage fluid. In my region, tank design must be compliance with API or ISO, could you please point out which API/ISO mention about this specification?
FYI, I have the same problem. A floating roof tank is already accepted, thus we have to determine how much vapor pressure that we should stabilize condensate before send it to tank.

Thank you so much
Eastorca

-I have corrected true vapor pressure limit for fixed roof tanks in post 2 of http://www.cheresources.com/invision/topic/9948-storage-tank-requirements-vapour-losses, seeing that 5.2 kPa (0.75 psi) mentioned by go-fish makes sense. Mentioned web reference also contains other data probably useful.
-1 barrel = 42 US gal = 42*231 in₃ = 0.159 m3. Tanks of 6 MM barrel = 954000 m3 seem too large to me, I have heard of e.g. 100000 m3. It is useful to check capacity again.
-Tank height can be also dictated by available space or max height permitted by law in the specific area of location. Tanks of such high capacity are usually constructed with low height to diameter ratio (flat), this resulting in minimum capital cost (for a given capacity)

[kkala]

Unfortunately, eastorca, I do not know whether a practice / standard covers the tank type selection, apart from mentioned book by Nelson and Greek ministerial decree 846/B. Losses to environment have to be minimized, so floating roof tanks are selected for volatile petroleum products. Reported vapor pressure limit at maximum possible operating storage temperature for floating roof tanks is 11 psia per Nelson, or 13 psia per what we have applied here. That 13 psia was found in manuals of refinery revamp (~1985). Besides isomerate (a liquid resembling gasoline) of max vapor pressure=13 psia was designed (2008) to be stored in a floating roof tank (not eventually constructed).
Mentioned stabilized condensate is assumed to have a flash point lower than max ambient temperature, which leads to floating roof tanks (assuming it valid in legislation of other countries, apart from Greece); but this does not inform directly about vapor pressure.

Note: Codes and Standards are not familiar to local Process. Tanks in refinery are constructed to API 650, briefly looked in past. Present topic has not been found..

Edited by kkala, 09 November 2012 - 05:14 PM.

[himant]

Hi

 

Above discussion is for tank roofs. My question is if there is any standard for selecting tank bottom? How to decide if we have to chose dished bottom or flat bottom or any other type?

 

Regads

Himant

[roy2377]

HI everyone, I need to size a heavy fuel oil tank for a factory, the factory needs 700 tons vapor per month.

Here at my place of oil we do delivery after 48hrs.  For example a client pass a command on Monday its wednesday that he will receive his product.  The max size of our HFO lorry is 25L.

 

Please can you help me what tank size should I place at the client.

 

Thanks a lot in advance

[sukanta87]

Hi all,

 

what should be the additional storage capacity of an oil storage tank (let it's fixed roof and atmospheric/low preesurized)?

Is it min. 110-130% of required volume ?

or

the height of additional storage capacity required shall be established to permit a minimum response time of fifteen (15) minutes in order to enable either diversion or total shutdown of inbound flow at the maximum product fill rates?.

Edited by sukanta87, 04 March 2014 - 12:55 AM.