methods of testing the quality control

1. Quality Control of
Petroleum Product
ATUL KUMAR PATEL
CSJMA14001390194
CHEMICAL ENGINEERING

2. INTRODUCTION
 Quality control of petroleum products is a necessity if the product are to give
satisfactory performance to the customers
 The usefulness of each product for specific purpose, standard organization
have methods of tests and specifications
 Bureau of Indian Standard(BIS), New Delhi, Institute of Petroleum(IP),UK
and American Society for Testing and Materials (ASTM),USA are the
organisations whose methods and specifications are widely followed
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3. CLASSIFICATION OF LABORATORY
TESTS
Most of the laboratory tests broadly classified into seven groups –
• Volatility
• Combustion
• Viscosity and Consistency
• Melting Point
• Oxidation
• Corrosion and protection
• Miscellaneous tests
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4. VOLATILITY
• Major Determinant of the tendency of a hydrocarbon to produce
potentially explosive vapours
• Critically important to an engine`s start and warm-up
• Assessed by the following tests:
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a) Distillation
b) Vapour pressure
c) Flash point and Fire point

5. COMBUSTION
The Combustion properties of petroleum products are evaluated by following tests-
a) Antiknock quality- Octane number, performance number
b) Ignition quality – Cetane number, Aniline point, Diesel index and cetane index
c) Calorific value
d) Burning quality- Smoke point, Char value
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6. VISCOSITY AND CONSISTENCY
Determination of viscosity and consistency of petroleum product done by
following tests-
a) Kinematic viscosity :- it is defined as the measure of the resistance to
gravity flow of fluid, the pressure head being proportional to density
b) Viscosity index:- it is used the effect of change of temperature on the
viscosity of any oil
viscosity index (VI) =
L−U
L−H
× 100
L,H,U= KV at 400
C of an oil of 0,100,calculated VI
c) Penetration Tests:- it can be used to defined the extent to which the
consistency of bitumen change with temperature
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7. MELTING POINT
The test designed to ascertain the tendency of certain petroleum
products to melt, liquefy, to solidify, to precipitate wax-like materials
are:
a) Freezing point
b) Cloud point and Pour point
c) Drop point of grease
d) Melting and Settling point of wax
e) Softening point of bitumen
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8. OXIDATION
Methods have been devised for the evaluation of storage stability and
resistance to oxidation for gasoline and aviation turbine fuel. These include:
a) Induction period of gasoline
b) Thermal stability of jet fuels
c) Gum content
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9. CORROSION AND PROTECTION
• Crude oils are corrosive to greater or lesser extent , frequently due to the presence
of Sulphur compound , organic acids and traces of brine
• Following methods are available to evaluate the corrosive potentialities of
petroleum:
a) Total Sulphur
b) Acidity and alkalinity
c) Copper-strip corrosion
d) Silver-strip corrosion test for ATF
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10. MISCELLANEUOUS TESTS
a) Ash
b) Carbon Residue
c) Colour
d) Density and specific gravity
e) Gas chromatography of petroleum gases and liquids
f) Refractive index of hydrocarbon liquids
g) Lead in gasoline
h) Water separometer index(modified)(WASIM)
i) Ductility
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11. VAPOUR PRESSURE
• Vapour pressure of a liquid fuel may be defined as the pressure exerted
by the vapour above the surface of the liquid at the given temperature
• For non volatile, non viscous petroleum products, it is determined by
“Reid method”
• The standard Reid apparatus consists of fuel chamber connected to an
air chamber of four times volume and fitted with a pressure gauge
• The true vapour pressure is higher than the Reid vapour pressure by 5
to 9% but this relationship varies widely
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12. FLASH AND FIRE POINT
• The Flash point is the lowest temperature at which application of test
flame causes the vapour above the oil to ignite
• The Fire point is the lowest temperature at which the oil ignites and
continues to burn for 5 second.
• Abel apparatus is used for the determining the closed cup flash point of
petroleum products having flash points between 19
0
C & 49
0
C and flash
point above 49
0
C, Pensky Martens apparatus is used.
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OCTANE NUMBER
The Octane number of the fuel is defined as the volume percentage of iso-octane
in a blend with n-heptane which is equal to the test fuel in knock intensity under
standardised and closely controlled conditions of test in a single cylinder, variable
compression ratio engines, known as CFR ENGINES
PERFORMANCE NUMBER
The performance number scale is based on engine power output. the rating of
aviation gasoline above 100 octane number are normally expressed as
PERFORMANCE NUMBER
OCTANE NUMBER=100+(PERFORMANCE NUMBER-100)/3

14. CETANE NUMBER
The Cetane number is related to the ignition delay of a fuel in a diesel engine, i.e. how
rapidly combustion begins after injection of the fuel into the combustion chamber.
Hexadecane has low ignition delay time and is the arbitrary chosen high quality
reference compound for the cetane scale
Shorter the ignition delay period, higher is the cetane number
CETANE NUMBER = %N-CETANE +0.15(%HEPTAMETHYL NONANE)
CETANE NUMBER = 0.72* DIESEL INDEX +10
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