Petrol storage?

[geem]

No winter. Gasoline in Minnesota has to evaporate when it is -40F.

Maybe but Caribbean doesn't freeze ever?
I found this article which suggests fuel in the Caribbean is pretty similar specification to USA and Europehttps://stratasadvisors.com/insights/2020/08212020-central-america-caribbean-fuel-quality

 

[Refueler]

Maybe but Caribbean doesn't freeze ever?
I found this article which suggests fuel in the Caribbean is pretty similar specification to USA and Europehttps://stratasadvisors.com/insights/2020/08212020-central-america-caribbean-fuel-quality

The actual make up of gasoline is a closely guarded confidential blend ... I would be breaking NDA's if I went into more detail.

The calculation and blend programs are not some simple spreadsheet and a few numbers thrown in. The blend can involve up to 20 different components, the sequencing of which into the blend is important as well as the % ...

Unless actually involved in the blending - then its all guesswork and supposition by outsiders. But what would I know about it ... I just blend about 60,000 MT each nomination.

As to the linked website ... notice that it literally says nothing of any real detail other than Sulphur levels .... which is off the mark anyway. Given that High Sulphur Gasolines and Diesels are generally not marketed anymore - even without state legislated Sulphur levels - the prevailing supply market will have meant low sulphur anyway.

 

[geem]

The actual make up of gasoline is a closely guarded confidential blend ... I would be breaking NDA's if I went into more detail.

The calculation and blend programs are not some simple spreadsheet and a few numbers thrown in. The blend can involve up to 20 different components, the sequencing of which into the blend is important as well as the % ...

Unless actually involved in the blending - then its all guesswork and supposition by outsiders. But what would I know about it ... I just blend about 60,000 MT each nomination.

As to the linked website ... notice that it literally says nothing of any real detail other than Sulphur levels .... which is off the mark anyway. Given that High Sulphur Gasolines and Diesels are generally not marketed anymore - even without state legislated Sulphur levels - the prevailing supply market will have meant low sulphur anyway.

So it's all the same spec then?

 

[Refueler]

So it's all the same spec then?

 

[emmalina]

Its actually the fuel going into vapour phase that causes the pressure ......

Temperature actually has a direct effect on fuel volume .... we use special tables every day to calculate this (ASTM VCF) .... each range of products has its own set of tables. Tanker Ships are not to exceed loaded to max 98% volume on any tank for this reason.,

If you do not think fuel expands significantly ....... then you have not seen an aircrafts wing tanks leaking if stood longer than planned and temp risen.

Can't go into vapor if there is no air in the container can it ? I keep a black drum of 30 liters on deck in the tropics with no problems but then it actually takes 32,5 liters to fill it to the brim.

 

[thinwater]

Can't go into vapor if there is no air in the container can it ? I keep a black drum of 30 liters on deck in the tropics with no problems but then it actually takes 32,5 liters to fill it to the brim.

There will always be some air. Maybe just a few cubic inches. Maybe less. But some.

The vapor pressure (air/gas mix) at 95F is about 8 psi, depending on the blend, but lets go with that. however, the only pressure that matters is the differential between the filling temp and the storage temp. Obviously, if you fill at 95F and open the vent at 95F, the pressure is the same. If you vent at 95F and then it cools, the tank can suck in (we've all seen this too).

Let's assume you filled at 75F and it reached 95F in the sun. The differential is only 3 psi. Assuming the can sides are very flexible, the gas will expand 17.7/14.7= 20%. If there are only a few cubic inches of air (3) in the drum, it will expand 0.6 cubic inches, each head will only need to move a few thousandths of an inch. There will be negligable pressure change. On the other hand, if the drum (or plastic jerry can) is only half full, the change in volume is 10%, which is considerable. There will be an increase in pressure, which reduces the volume change. You may have filled from an under ground tank (55F) and the pressure swing will be greater. Many possible combinations.

But the less air volume, the less expansion. As long as the tank is flexible, very full can result in the lowest pressures. But you need to consider ALL of the variables.

 

[Spirit (of Glenans)]

The Eighth Army, in Libya in 1942 had problems with petrol cans that were probably OK for UK conditions but were not robust enough to withstand the expansion caused by the desert heat. They quickly learned to get hold of German (gerry) fuel cans whenever they could, and eventually the German design was adopted as the standard fuel can of the Allies.

 

[geem]

There will always be some air. Maybe just a few cubic inches. Maybe less. But some.

The vapor pressure (air/gas mix) at 95F is about 8 psi, depending on the blend, but lets go with that. however, the only pressure that matters is the differential between the filling temp and the storage temp. Obviously, if you fill at 95F and open the vent at 95F, the pressure is the same. If you vent at 95F and then it cools, the tank can suck in (we've all seen this too).

Let's assume you filled at 75F and it reached 95F in the sun. The differential is only 3 psi. Assuming the can sides are very flexible, the gas will expand 17.7/14.7= 20%. If there are only a few cubic inches of air (3) in the drum, it will expand 0.6 cubic inches, each head will only need to move a few thousandths of an inch. There will be negligable pressure change. On the other hand, if the drum (or plastic jerry can) is only half full, the change in volume is 10%, which is considerable. There will be an increase in pressure, which reduces the volume change. You may have filled from an under ground tank (55F) and the pressure swing will be greater. Many possible combinations.

But the less air volume, the less expansion. As long as the tank is flexible, very full can result in the lowest pressures. But you need to consider ALL of the variables.

We bought our four plastic 20 litre fuel cans in 2005. They have been well used ever since lugging fuel and when full they live on deck. They are a good design that I have never seen since. We are very careful to never leave them half full as they swell alarmingly. Fortunately our dinghy fuel tank is 24 litres so a full can fits in the fuel tank with some spare.
This is how they are stored under the granny bars. Excuse the incredibly dirty decks. We are in Bonaire and with the huge Sahara dust storm we have just had and the wind blown dust of Bonaire our boat is filthy. Off to Curacao Marine tomorrow where we can clean everything?

 

[thinwater]

The Eighth Army, in Libya in 1942 had problems with petrol cans that were probably OK for UK conditions but were not robust enough to withstand the expansion caused by the desert heat. They quickly learned to get hold of German (gerry) fuel cans whenever they could, and eventually the German design was adopted as the standard fuel can of the Allies.

You'd wonder how a guy could talk about a jerry can for 30 minutes, but he does so with ease.
jerry can history

 

[MADRIGAL]

Believe it not ... your choice.

Of course fundamentally they will work in all climates within reason - but having blended Gasoline and Diesels for many years - I can state clearly that blending does occur based on location. My job was to blend base Gasoline - the final blend analysis would determine destination of that volume. Could be West Africa, Caribbean or Europe. Once destination decided - it would sail and offload to bulk terminal for final blend processing for that market.
Variations on Colour, Oxidation Stability, RVP, Density, Distilation Curve and Recovery %. Are just a few of the tests determining destination and final processing.

Interesting. I had no idea. Thank you for the professional expertise.

 

[Spirit (of Glenans)]

You'd wonder how a guy could talk about a jerry can for 30 minutes, but he does so with ease.
jerry can history

Interesting video.
On the maritime side, Calum has an excellent feature on the Russian Black Sea Fleet's 110 year-old submarine rescue ship. It can be found at the end of the gerry can one.