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Old 23rd February 2009, 09:07   #31
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Default Most fascinating - but am still clueless!

Wow, this is one of the most fascinating threads. Thanks guys for all the detailed information that you have shared here.

I used petrol engines for about 20 years and have just started using a Diesel burner. First off, petrol is easier to check - smell, vapurisation etc. plus, the engine used to sound crisper (It sounded like you could hear each detonation clearly) when the fuel was clean, if the fuel was not so clean the engine would kind of slur (a bit like a drunk rolling all his words into each other). Will the Diesel engines behave the same way?

I sure hope I can figure out a decent way of distinguishing adulterated Diesel fuel soon without doing several lab tests. (I have not been in a lab since 1981!)

Cheers,
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Old 23rd February 2009, 10:22   #32
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My take on restricting PDS Kerosene getting into Diesel or Petrol is to stop PDS of Kerosene. Have Cooking Gas PDS instead. Government can also supply Cooking gas stoves at a cheap cost (Now the technology is such that the cost of gas stove will be same as kerosene stove if manufactured and distributed in Bulk). This will lead to stopping of adulteration as well as improved standard of living for the poor.

I know this is OT but wanted to put this point out there. Mods you may create a new thread if needed.
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Old 23rd February 2009, 16:29   #33
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Enlightening discussion! But the question still remains unanswered, how does one know if you are getting pure diesel. Till such time that we get a guage to measure the purity of diesel the way you measure the tyre pressure, let us all keep the faith in our respective petrol pumps and believe that what we pay for is pure diesel.

Dr Sumit Bhatti, you seem to knowing all about the petroleum industry. I have seen your posts on three forums concerning fuel. All your posts were brilliant! Thanks for sharing your knowledge.
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Old 23rd February 2009, 17:12   #34
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Quote:
Originally Posted by dushmish View Post
Dr Sumit Bhatti, you seem to knowing all about the petroleum industry. I have seen your posts on three forums concerning fuel. All your posts were brilliant! Thanks for sharing your knowledge.
+1 ^^!

I suspect it is a cover, the ENT (?) part.
He's actually an undercover agent of some sort!
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Old 23rd February 2009, 17:19   #35
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Quote:
Originally Posted by Dr.Sumit Bhatti View Post
Tamper-proof kerosene: there’s proof it can be tampered

I was, however, closely involved in marker research and have seen these incidents unfold in real time.
That link made for very interesting reading. And to think that you are/were actively involved in research into petrochemicals is even more interesting, considering that you are from a medical background. Me, I got into medicine after spending well over 15 years dabbling with cars & bukes in garages and workshops - and even through my medical career that relation continued.

I wonder about you...
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Old 23rd February 2009, 19:36   #36
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Doc, your posts are eye openers. Please keep posting such gems for us
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Old 23rd February 2009, 23:50   #37
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just wondering whether gases like lpg and cng can also be adulterated ? apart from higher octane rating this seem to be the one of the main advantages of these fuels. I have heard from somebody that most of the petrol/diesel bunks cheat on either the quantity or quality of fuel supplied .
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Old 24th February 2009, 01:10   #38
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Cool Advantages and Disadvantages of LPG and CNG.

Quote:
Originally Posted by ask77 View Post
apart from higher octane rating this seem to be the one of the main advantages of these fuels .
CNG:
1. is a zero-sulphur fuel
2. produces low-particulate emissions.
3. produces less CO, CO2 emissions.
4. has superior anti-knock performance, thus allowing higher compression ratio engines, leading to greater efficiency.
5. produces less nitrous oxide emissions.
6. requires energy to compress it, creating extra CO2 emissions (4% more than the vehicle that runs on it).
7. has to be transported as a gas through pipelines.
8. can be stored at 200 bars, which takes 3 to 5 times more volume for storage than petrol.
9.Vehicle engine, tank conversion and maintenance costs 10 per cent more.

LPG:
1. is a mixture of light petroleum gases (ethane, butane).
2. produces low-particulate emissions.
3. has lower CO, CO2 emissions.
4. has lower nitrous oxide emission.
5. has low-sulphur content.
6. is transported in liquid form.
7. is under low pressure (5 bars) in sealed aluminum walled tankers.
8. has negligible evaporative losses.
9. is heavier than air, hence it requires special safety measures.
10. delivery to the service stations is more expensive than the delivery of liquid fuels.
11. Vehicle engine, tank conversion and maintenance costs 10 per cent more.
12. is introduced where urban pollution is problematic.

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Old 24th February 2009, 02:09   #39
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Cool Can LPG and CNG be adultrated?

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Originally Posted by ask77 View Post
just wondering whether gases like lpg and cng can also be adulterated ?
Why bother to try and adulterate LPG and CNG when you can short sell?

You might be surprised, but there are no W&M (Weights & Measures) Rules and Regulations to check and stamp the calibration of LPG and CNG dispensing pumps !

(Petrol and Diesel dispensing units, on the other hand, have strict calibration, checking and stamping procedures.)

The W&M Department is still working on this. Till then, only the parent company calibrates the dispensing units. No stamping is done by W&M.

So, at present, you are entirely at the mercy of the settings on that dispensing unit !!
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Old 24th February 2009, 03:30   #40
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Cool So why do the petrol dealers adjust?

Quote:
Originally Posted by ask77 View Post
I have heard from somebody that most of the petrol/diesel bunks cheat on either the quantity or quality of fuel supplied .
Did you know that for most of the past decades, THE eligibility criteria for getting a petrol pump dealership was a combined family income below Rs. 2,00,000/- per annum ?

99% of petrol pump dealers do not know exactly what Temperature Correction or Temperature Compensation of Liquid Fuels is. It is the best kept secret of the oil industry worldwide.
Please refer to the thread: http://www.team-bhp.com/forum/indian...y-display.html (Pumps with fuel density display)
for a part explanation.

What happens in reality is that the fuel which is not Temperature Corrected shrinks when it goes into a cooler underground storage tank at the petrol pump. So the petrol dealer cannot sell all the liters that he has purchased. These are known as 'Phantom Liters'.

The petrol dealer also pays Sales Tax, in advance on these 'Phantom Litres' which he cannot pass on to the customer. Neither does he get a Sales Tax rebate, except a notional rebate in West Bengal !
Best is a COCO pump next door to such a petrol dealer in India: The COCO receives only Excise Paid fuel, that is also Temperature Corrected !! This is shown as a stock transfer so it's not the first sale as in the case of an ordinary petrol dealer. Hence the first sale in case of a COCO Pump occurs at the nozzle directly to a customer, the COCO pump totals the weekly sales and then pays Sales Tax to the State Government ONLY on the ACTUAL SALE, not on invoiced liters ! (Divide and Rule ?) (Constitutional Equality?)

You might ask why this was not a problem in the past? Some of the reasons are:
1. A few decades ago, this problem of temperature correction was minimal because fuel depots had underground storage tanks too. Hence the temperature difference in supplies to petrol pumps from underground tank to underground tank did not vary much as ground temperature is fairly constant in a small geographic area. Petrol depots were very near petrol pumps.
Now large depots have been shifted out and have above ground storage tanks. The temperature of the supplies can be as high as 45 degrees ! (Sunlight and agitation during transport further increases the temperature).

2. Margins were between 7 to 10 %. After nationalization in 1974, dealer margins were more or less frozen EVEN THOUGH THEY COME DIRECTLY FROM THE CUSTOMER ! Today retailer margins are about than 2% and have varied between 1.3% to 2%.

3. In the 1950's and 60's, petrol dealers got reimbursed for electricity, telephone bills, air compressors, air gages, uniforms (that how the concept of free air was born) but not today!
Up to 15 days credit was available on petrol and diesel and three months credit on lubricating oils! Recently, R.T.G.S. (Real Time Gross Settlement like N.E.F.T.) has been introduced for payment in advance so some petrol dealers actually end up paying on Friday for stocks received on Monday!

4. You might say that on paper it sounds good, given today's sales. You are right. But remember:
For every 8 degrees C difference in temperature, petrol volume expands / contracts by 1%
For every 8 degrees C difference in temperature, diesel volume expands / contracts by 0.6%
Therefore, if petrol is supplied to a petrol dealer at 31 degrees C, instead of the world standard of 15 degrees C, you loose 2 % volume!
So you are trading the fuel for free or with a loss in capital.

5. The Slab system: For past decades, till it was abolished in the late 90's, there was also a slab system of dealer commission. There were four slabs in sales figures: The more you sold, the lesser your margin would become. And if you sold more than 50,000 liters of one product (1st slab), then your commission for second product automatically fell for the other product to the 2nd slab! Shocking, but true.

6. This is the real reason that forces a petrol dealer to adjust. Most honest dealers will cross subsidize their petrol pumps with income from allied businesses. When this fails, some short sell. When this fails, some adulterate and some leave the dealership or sell out.

If you look at the long standing (till recently) criteria for selection of a petrol dealer above, he or she would not survive the first years' balance sheet of that petrol pump!

And when petrol dealers have asked their oil companies in the past to explain this loss, vague answers like evaporation, tank breathing, pilferage and even supernatural (sic) causes have been mentioned in Inspection and Call Reports (which can only be made by Gazetted Officers). The above causes have been scientifically proven to be negligible! Only theft en-route is a significant cause, but it is only possible because Temperature Correction is not applied.
On top of this there is a peculiar rule that makes +4 to -4% variation in tank stock volume actionable. So in most inspections, petrol dealers were told to be thankful that no action was being taken 'this time' and in many cases, Sales Officers of the Oil companies would spend hours using every maths trick in the book to get tank variation into 'normal' limits. It took decades to convince the Oil Ministry of the simple fact that one can be penalized for > +4% stock, but not a > -4% loss !

It is impossible to fit 50 years of history into this small box, but in short, the honest petrol dealer is as much a victim as a customer is.

Given Temperature Correction, cheating at petrol pumps will disappear. And who knows this better than the Oil Companies, who use Temperature Correction day in and day out among themselves?
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Old 24th February 2009, 08:57   #41
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Gosh, Doc. Bhatti, you are an education!

Thanks so much!
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Old 24th February 2009, 19:52   #42
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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
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Old 24th February 2009, 21:47   #43
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Interesting topic, not being regular, missed out the same.

I think, we did discuss similar things long time back.

The most accurate check is lab test only.

Other test is the density and viscosity test. 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.

When the fuel is contaminated, the density and viscosity is bound to change. (Viscosity is difficult to measure except with some comparator type is available - other devices are expensive and won't be kept by pump guys)

The oil companies provide the standard density correction and viscosity correction tables w.r.t. temp and should be available with pump guys.

(There is a formula for density and viscosity correction for all type of oils, but then it is a bit complex for most of the people and requires scientific calculator - tables are easiest method - and are standard system in case of dispute)

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.

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)
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)

Antoher method of comparison is use of filter paper. The uncontaminated fuel forms a clean circle (not perfect circle) when a drop of oil is put on the filter paper. A contaminated fuel will show two or more circles or spots.

Last edited by jat : 24th February 2009 at 21:52. Reason: Adding the filter paper test
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Old 24th February 2009, 23:05   #44
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Dr Sumit - This thread has been the most informative thread that I have come across at Team Bhp. This is for the first time that I am reading this thread and was really impressed at the way you have explained everything. With all this knowledge, there is one question that crops up to my mind, "which petrol pump do you use for refueling."I am sure that would be the pump that I would like to refuel too.

Thanks a lot for all the information provided, i am in awe.

Regards,
Kailash
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Old 24th February 2009, 23:21   #45
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Quote:
Originally Posted by Dr.Sumit Bhatti View Post
Why bother to try and adulterate LPG and CNG when you can short sell?

You might be surprised, but there are no W&M (Weights & Measures) Rules and Regulations to check and stamp the calibration of LPG and CNG dispensing pumps !

(Petrol and Diesel dispensing units, on the other hand, have strict calibration, checking and stamping procedures.)

The W&M Department is still working on this. Till then, only the parent company calibrates the dispensing units. No stamping is done by W&M.

So, at present, you are entirely at the mercy of the settings on that dispensing unit !!
Well short selling is lesser of the two evil if you compare it to adulterated and/or contaminated petrol/diesel . Today's modern engines are made with such close tolerance to give that much high refinement, power and fuel efficiency that adulterated or contaminated fuel can shorten their life considerably . It is very difficult to pin point adulteration but anyone who closely monitors their vehicles FE can detect if a particular pump is short selling or not .
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