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Old 25th February 2009, 03:06   #46
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Cool A good guess !

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Originally Posted by GSMINC View Post
Dr.Bhatti, you seem to know much about the fuel industry,
Does anybody in your family own a petrol pump, or is it a Khandani Business
Was a Khandani Business !
My Grandfather, S. Teja Singh operated 5 Burmah Shell and 1 Esso Petrol Pump, the oldest since 1953.
I was a 3rd generation Petrol Dealer, till I did a 3000 page study on the business for FAMPEDA ( Federation of All Maharashtra Petrol Dealers' Associations) and FAIPT (Federation of All India Petrol Traders).
That's when I opted out in 2005 by choice.

But I ensured that my existing outlets are now COCO Pumps, because I do have to fill up there myself.( Please do not construe this to mean that all COCO's are safe. Mine are because I keep an eye on them!)

Shell has not given any dealerships in India at present. They definitely will, in the future. Maybe 5 to 10 years down the line, if business conditions are ideal, I may re-start some outlet. After all, petrol is in my blood.
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Old 25th February 2009, 04:13   #47
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Cool ASTM Reference Tables for Density @ 15 șC

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Originally Posted by jat View Post
Interesting topic, not being regular, missed out the same.
Each tanker while delivering fuel to the pump, gives a sheet which gives the SG @ 15/4 deg C (upto 4 decimals) or density, the density at delivery temp, viscosity etc. Also a density correction factor is given. You can measure the SG at room temp and then from the tables apply the correction (or you can use the correction factor from fuel receipt provided by tankers) and get the corrected SG at 15/4 deg and compare.

The fuel is never supplied at 15 deg C anywhere in world. The volume/weight is corrected to 15/4 deg from tables. You can see on any fuel receipt of the tanker. It is mandatory. Now some pumps are having the automatic temp compensation fitted in fuel dispensor, but only the modern ones. Old ones are still going by old system of dispensing. Also please note that the metering system also has inherent error in measurement (their certificate will show the error)
On 28th December, 1998, the Ministry of Petroleum and Natural Gas (MOP&NG) notified the Motor Spirit and High Speed Diesel (Regulation of Supply and Distribution and Prevention of Malpractices) Order, 1998, requiring all Oil companies to use new ASTM tables 53B and 54B in place of old ASTM tables 53 and 54 respectively.

You are correct in stating that density was earlier in 4 decimals (e.g. 0.7348), but that was a decade ago. Since 1998, density is now stated in 1 decimal (e.g. 734.8) in view of the above.

Also note that density is the same as specific gravity (SG).

The Petrol Pump Invoice (Bill) gives the density taken at the time of filling, then referenced to a standard 15 șC. It does not give the density at delivery temperature because this is variable. That is why density has to be taken again and then corrected to standard temperature @15 șC. Then both the filling and the delivery density readings can be compared. They should be within a range of +/- 000.30.

No density correction factor is mentioned on the tank truck invoice, neither is viscosity, though weight is mentioned sometimes but only for their internal use. At present, Weights & Measures Rules do not allow measurement of liquid fuels by weight except for LPG, which may be measured in liters or kg.

Density is not measured at room temperature. Fuel is poured into a 500 ml. glass jar. Density is measured by an appropriate hydrometer in conjunction with an alcohol thermometer simultaneously submerged in the fuel. These 2 readings, the density and the temperature are matched on an ASTM (American Standards of Testing of Materials) Reference Table to arrive at the density of the fuel which would been @ 15 șC.

You are also correct in stating that no where in the world is fuel supplied @ 15 șC. Yes, this is not feasible. You cannot cool the fuel to 15 șC all the time, hence the ASTM tables.

This density conversion in India to 15 șC is only for detecting adulteration, not to be confused with volume correction.

Oil Companies in India also use this density correction for volume correction only between themselves:
1. when they exchange product.
2. for internal accounting.
3. for payment of Central Excise Duty.
4. for Sales Tax Rebate.
5. for bulk supplies to Defence, Railways, Airways.
6. for stock transfer to their own COCO pumps (but not for their COCO labor contractor). It might be interesting for you to know that COCO pumps do not have their own balance sheets. Their operations are part and parcel of their parent oil company's balance sheet.

Standard Temperature Accounting (STA = converting volume to 15 șC) is conveniently not followed for sales to the final two links in this chain: The Petrol Dealer and The Customer/ Consumer. (Please note: STA is applied to retail sale to consumers in many countries worldwide).

There are no operational Automatic Temperature Compensators fitted in fuel dispensers at any Petrol Pump in India at present. This is what an ATC looks like:


But they can be retro-fitted or activated if we, as customers, insist.

Continued in next post.
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Old 25th February 2009, 04:56   #48
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Cool Phantom Liters - Myth or Reality?

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Originally Posted by jat View Post

Regarding the "Phantom Oil" or "Dead Oil", it is a constant and the pump owner suffers only the first time filling. So this is not an excuse.
A) What is Temperature Correction?

1.Temperature Correction is the process of converting a volume of fuel at ambient temperature to a volume that the fuel would occupy if it’s temperature was 15 degrees Celsius.

2. It is the process of determining theoretically what volume of fuel there would have been at 15 șCelsius, compared with the actual volume at ambient (actual) temperature.

B) Why does it happen?

1.Because fuel expands with heat and contracts when cooled,

2. Regulations have been introduced in other countries to improve certainty and transparency in the measurement and pricing of fuel.

C) How much does fuel expand / contract?

For every 8 degrees Celsius,
Petrol volume expands / contracts by 1 %
Diesel volume expands / contracts by 0.6 %

D) How does this affect the Petrol Dealer?

Petrol stations receive less fuel from Oil Companies than paid for. ( These are known as 'Phantom liters' )
Fuel measured by volume and loaded on to road tankers is above ambient temperature as oil terminals have above ground storage tanks.
The temperature rises further during transport.
The fuel cools and therefore shrinks after decantation into the underground tanks.
Thus there is less petrol available for sale than purchased. EVERY TIME.

If you see a regular Petrol Tanker Bill, you will notice that there is a column for this temperature correction that is never filled. In many locations in India, there are hospitality arrangements among oil companies and depots. If you see that hospitality bill which other oil companies (which do not run that depot) use to fill their tankers at the gantry, you will see that the temperature corrected quantity (and hence weight) filled is always different (less) than that on the fixed final invoice quantity, (Petrol tank trucks are usually either 12,000 / 20,000 / 40,000 liters and fuels are usually sold in multiples of 'compartments': 3,000/3,500/4,000/4,500/5,000 liters) and that the temperature corrected quantity (and hence weight) also changes during different times of the day! The price computed on that inter-company bill is also different (less) from that on the final dealer invoice.

E) What is 'Dead' Stock?

The suction pipe of an under ground storage tank is a few inches above the bottom of the tank. This ensures that no clogging takes place and no water or sludge in dispensed as far as possible. The quantity of fuel that cannot be suctioned out in normal day to day dispensing is known as 'dead' stock. It arises at the time of initial filling and is only removed during tank cleaning, or when replacing the tank. It's composition, however, never remains constant and changes with every load.

Continued in next post.
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Old 25th February 2009, 11:25   #49
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Dr Bhatti, is there any truth to the belief that premium fuels are less adultrated (or have less chances of adultration)? My logic says that it makes sense for the petrol pump owner to adultrate the premium fuel more than the regular ones as his realisation per litre is more there. But still most of us tend to believe that premium fuels are less adultrated.

My second question is that are premium fuels are any better? Specially premium diesel?
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Old 25th February 2009, 12:11   #50
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Quote:
Originally Posted by Dr.Sumit Bhatti View Post
There are no operational Automatic Temperature Compensators fitted in fuel dispensers at any Petrol Pump in India at present. This is what an ATC looks like:


But they can be retro-fitted or activated if we, as customers, insist.

Continued in next post.
This would have been my next question, but you already answered it.

Now how can we push the oil companies to install these ATC's who needs to be contacted, what needs to be done ??

Rated this thread as 5*, Dr. Bhatti, you need to be our "distinguished BHpian" for your indepth knowlege into this matter.

Last edited by dadu : 25th February 2009 at 12:13.
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Old 25th February 2009, 13:23   #51
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Dr Bhatti - you are the God of Fuel Quality on TBHP... Hail Thee...
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Old 25th February 2009, 14:27   #52
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Dr Bhatti, you cannot be gone for so long treating ear, nose and throats of people. TBHPians are waiting for your posts with bated breath.
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Old 25th February 2009, 21:28   #53
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Cool Tank Breatning Losses.

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Originally Posted by jat View Post
There is a loss of oil through tank breathing and those vapours in the air are highly combustible and hence you are not suppose to smoke, use mobile etc near the pumps (there is a basic safety distance depending to tank construction, venting etc - but nobody follows that in India)
Please bear with me as I answer a few important points:

True losses can result from a number of mechanisms namely:
1. Incomplete emptying,
2. Spillage,
3. Pilferage (theft),
4. Leakage,
5. Vapour loss on transfer, and
6. Breathing losses from storage tanks.

Vapour losses on transfer arise from two sources,
A. Loss of vapour in the ullage space and
B. Outgassing of volatile components during the transfer.

(Note: Ullage Space is the space between the top of your tank and the level of the fuel in your tank.)

A. Vapour loss from the ullage space arises when the mixture of air and fuel in the ullage space in any tank is displaced by the incoming liquid fuel.
Subsequently, as the fuel is used, fresh air is drawn into the tank to replace the volume of the fuel withdrawn. The fuel then evaporates from the bulk liquid in the tank until the air in the ullage space reaches saturation.
The mechanism occurs:
1. When fuel is put into terminal storage and dispensed to the tanker,
2. When fuel is put into the tanker and discharged to the retail tanks,
3. When it is loaded into the retail tanks and dispensed to the motorist, and finally
4. When the vehicle tank is filled and fuel pumped to the engine.

Past practice was for the air/vapour mixture to be expelled to the atmosphere via the tank vent and the fuel was therefore lost to the environment. With modern petrol engine burning about 98% of the fuel entering the cylinders and with catalytic converters processing about 75% of unburnt fuel leaving the engine, total emissions from the engine exhaust represent only about 0.5% of fuel usage. Vapour losses from ullage spaces are likely to be of the order of 0.15-0.2% at each of the stages listed above and the fuel supply chain emissions are therefore comparable with vehicle operating emissions. This has led to the progressive introduction of vapour recovery technology starting at the refinery end of the supply chain. Current, vapour recovery, practice at the retail filling station is to draw the air/vapour mixture into the ullage space on the tanker to avoid the discharge to the environment. As a result the retailer should incur a similar loss as previously and the fuel supplier is left to dispose of the vapour in a less harmful way. The methods of disposal permitted depend on the size of the depot with some sites being allowed to flare the mixture, to release carbon dioxide and water vapour instead of more damaging hydrocarbons, while others are required to recover the vapour back to the refinery process.The amount of fuel lost as ullage space vapour depends on the vapour pressure of the fuel.
Losses of diesel will be insignificant due to the very low vapour pressure; losses of petrol will depend on the temperature of the ullage space and on the volatility of the fuel, which varies with the season of the year to meet the conflicting requirements for cold starting and vapour lock in the vehicle fuel system.

B. Outgassing of volatile components. As already mentioned, liquid hydrocarbon fuels are complex mixtures of many components. In the case of petrol these components will include volatile components such as butane and pentane. These components, included to satisfy vehicle cold starting requirements, will evaporate readily and may even come out of solution to form vapour bubbles in the transfer pipes as pressure in the liquid falls below the effective vapour pressure. Pressure drops will occur whenever a liquid flows; pressures in the filling pipe are therefore lower than in the supply tank. Any bubbles formed will re-condense when the liquid pressure rises again as it comes to rest in the storage tank. If, however, they are able to rise to the surface before re-condensing they will be released as vapour to the ullage space and expelled with the normal ullage air/vapour mixture as already discussed.

The outgassing process results in the air/vapour mixture expelled from the tanks being super-saturated with vapour and as a result condensation will occur.
This can happen intwo ways:
1. A fog can form in the air stream and fine droplets will then move with the air into the tanker or out to atmosphere, or
2. Droplets of condensate can form on the pipe walls.
In the case of a fixed vent stack condensation forming on the pipe walls will ultimately drain back into the tank or evaporate into the air drawn into the tank during retail dispensing. In the case of a tanker vapour recovery system, the normal practice is to elevate the lines at the end of the filling process to drain any condensate back into the retail tanks. The extent of any condensation process will depend on the temperature of the pipe walls relative to the saturation temperature of the air /vapour mixture. As outgassing is a volatility phenomenon it will only occur with petrol and is strongly dependent on the temperature, which controls the vapour pressure.

The potential for outgassing has always existed but it increases with liquid velocity in the transfer pipes. Changes in practice with the introduction of vapour recovery systems may therefore have an influence as vapour recovery lines to tankers are generally larger than tank vent lines and so present less resistance to flow of vapour, reducing static pressure and hence potentially increasing vapour concentration. Seasonal changes in volatility will also impact on the occurrence of this loss mechanism. Where liquid is stored under pressure it has the potential to hold higher concentrations of volatile components in solution and so will have a higher vapour pressure. Such fuel would be more prone to outgassing problems.

Breathing losses from storage tanks: In normal operation the vent pipe on a tank will serve only to admit air to replace the volume of liquid dispensed to the motorist. However, under some conditions, the gas in the ullage space may expand and some will be expelled through the vent and released to atmosphere.The principal cause of this will be a reduction in atmospheric pressure when ullage gas will be vented to equalize the pressures in the tank and at the vent. The expelled gas will take with it a proportion of the vapour in the tank. This vapour will disperse and, when the atmospheric pressure rises again, pure air will be drawn into the tank allowing additional evaporation from the bulk liquid.
Wind blowing across the vent pipe will also generate a low pressure at the vent, creating a mechanism similar to atmospheric pressure changes with vapour being lost when the windblows and air drawn in when the wind drops.
Changes in temperature will create the same effect as the ullage gases expand and contract.These breathing losses can therefore be seen to be dependent on the site exposure, but at most sites are likely to be substantially less than the vapour losses incurred in tank filling. Being vapour losses, they occur only with petrol and are dependent on the storage temperature.
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Old 25th February 2009, 22:42   #54
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Dr. Bhatti,

Are you the author of any papers?

http://www.nwml.gov.uk/fileuploads/D...Comp_on_LF.pdf

Last edited by anupmathur : 25th February 2009 at 22:46.
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Old 25th February 2009, 22:44   #55
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Quote:
Originally Posted by Dr.Sumit Bhatti View Post

Was a Khandani Business !

My Grandfather, S. Teja Singh operated 5 Burmah Shell and 1 Esso Petrol Pump, the oldest since 1953.


After all, petrol is in my blood.
That is true, of course, petrol is indeed in your blood
it is a pleasure to take a sip from your ocean of knowledge.
hamara janam saarthak ho gaya.

To quote a tamil comedian: adra sakka, adra sakka,adra sakka.(tbhp members conversant in tamil pls translate)
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Old 25th February 2009, 22:58   #56
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@Dr. Bhatti: That's a wonderfully lucid explanation of many behind-the-scene processes in the petroleum industry, which directly concern us as interested motorists. Been reading all your posts with great attention.

Interesting read about the etymology of the word "ullage" at Ullage - Wikipedia, the free encyclopedia. Who said alcohol and driving don't mix? It sure does in the ullage space...
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Old 26th February 2009, 02:35   #57
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Cool Papers presented earlier.

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Originally Posted by anupmathur View Post
Dr. Bhatti,
Are you the author of any papers?
Yes, in Medicine and the Petroleum Trade. Recently, I have performed the first BAHA (Bone Anchored Hearing Aid) Surgery in Pune. This is a new type of hearing aid which clips on to a titanium fixture drilled into the skull behind the ear. I presented this case at the AOI (Association of Otolaryngologists), Pune Branch last month. (pic attached).


I have also pioneered the indigenous fabrication by L&T (Bilaspur) of a Tata 407 chasis into HARK (Hearing Assessment and Research Centre), a sound-proof van for hearing assessment in rural areas where these facilities are not available. The funding is by Sound Seekers – The Commonwealth Society of Deaf, U.K. and Big Ears, K.E.M. Hospital, Pune. The running costs and grants are donated generously by Manisha and Devindra Chainani and the IMPACT project. Devindra Chainani, incidentaly is the GM of Trident-Oberoi. He faced 26/11 in that capacity. (pics attached).

There are many presentations of mine on petroleum which are in circulation in the oil industry. One such presentation was on Sales Tax on fuels in Maharashtra State. It was appreciated by Mr. Sharad Pawar. However, there is no way to increase revenue figures by decreasing taxes!

I also have a presentation on RTI (Right to Information) Act, if anyone is interested. Some of these facts have been revealed to the Petrol Dealer Associations under RTI.

The NEL Article you have located is good. Search for articles on Temperature Correction from Australia, they are even better.
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Old 26th February 2009, 05:03   #58
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Cool Branded Fuels.

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Originally Posted by dushmish View Post
Dr Bhatti, is there any truth to the belief that premium fuels are less adultrated (or have less chances of adultration)? My logic says that it makes sense for the petrol pump owner to adultrate the premium fuel more than the regular ones as his realisation per litre is more there. But still most of us tend to believe that premium fuels are less adultrated.

My second question is that are premium fuels are any better? Specially premium diesel?
Some points to ponder:

1. Have you ever seen a manufacturer endorsing a product without having a stake in it ?

2. Branded fuels are free of Price Control. Oil Companies have a free hand at pricing branded fuel.

3. A rough estimate is that branded fuel adds at least 6 - 8 crores extra per day across India to the oil industry kitty.

4. Thankfully, highly over-priced branded fuels with respect to normal fuels will have no buyers, that's what actually keeps prices in check.

5. Most of the initial petrol pumps selling only branded fuel will be COCO's.

6. Recently, there has been a PIL against forced supply of only branded fuel.

7. If you treat your vehicle like a child, not filling in 'premium' fuel is 'emosional attyachar'. It's normal human tendency to feel guilty.

8. No additive can promise extra mileage beyond 5% taking into account all possible effects. If you notice, branded fuels are around 10% more expensive.

9. If 1 ml per liter of branded additive, sold in a small retail pack , costs barely a rupee more, why does the same additive added in bulk cost two to four rupees more?

10. Higher performance (compression) engines will require higher octane fuel to prevent knocking. MPFI vehicles can handle a wider range of fuels.

11. You can use branded fuels in premium cars, regular fuel is fine for regular cars. Occasional use of branded fuel or additives to wash out gum, varnish, rust and to remove moisture and corrosion is fine.

12. As far as adulteration of branded fuel is concerned, your guess is as good as mine ! Shell follows the best industry practices in India at present. Wherever available, and whenever reasonably priced, their petrol stations are the best bet.
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Old 26th February 2009, 10:45   #59
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Quote:
Originally Posted by Dr.Sumit Bhatti View Post
The NEL Article you have located is good. Search for articles on Temperature Correction from Australia, they are even better.
LOL, Dr. Bhatti, that is not quite what I intended!

Dr. Bhatti, do you seriously believe you can lift entire paragraphs from other people's publications without it being considered as plagiarism?

Here is the paper from which you have lifted extensively and failed to give due citation or credit!

NEL_REPORT_Temp_Comp_on_LF.pdf
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Old 26th February 2009, 13:29   #60
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Cool Should have added a footnote!

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Originally Posted by anupmathur View Post
LOL, Dr. Bhatti, that is not quite what I intended!

Dr. Bhatti, do you seriously believe you can lift entire paragraphs from other people's publications without it being considered as plagiarism?

Here is the paper from which you have lifted extensively and failed to give due citation or credit!

Attachment 105333
Apologies for not having added a citation. I will be more careful in future.
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