FUELS and COMBUSTION-3

REQUIREMENT OF AUXILIARY FUEL

CLASS-A petroleum having a flash point below 23⁰C
CLASS-B petroleum having a flash point of 23⁰C and above but below 65⁰C
CLASS-C petroleum having a flash point of 65⁰C and above but below 93⁰C

This is defined as the ratio of the mass of the fuel to the volume of the fuel at a reference temperature of 15°C.
Density is measured by an instrument called hydrometer.
The knowledge of density is useful for quantity calculations and assessing ignition quality.
The unit of density is kg/m³.

This is defined as the ratio of the weight of a given volume of oil to the weight of the same volume of water at a given temperature.
HIGHER SPECIFIC GRAVITY MEANS HIGHER CARBON TO HYDROGEN RATIO
HEAVIER OILS HAVE LOWER GCV
AROMATICS HAVE HIGHER SPECIFIC GRAVITY THAN PARAFFINS.
INCREASE IN SPECIFIC GRAVITY MEANS DECREASE IN PARAFFIN CONTENT

The viscosity of a fluid is a measure of its internal resistance to flow.
Viscosity depends on temperature and decreases as the temperature increases.
Any numerical value for viscosity has no meaning unless the temperature is also specified.

THE MIN. TEMP. AT WHICH AN OIL GIVES OUT SUFFICIENT VAPOUR TO FORM AN INFLAMMABLE MIXTURE WITH AIR AND CATCHES FIRE MOMENTARILY WHEN FLAME IS APPLIED.

IT IS THE LOWEST TEMP. AT WHICH VAPORS GIVEN OFF BY OIL IGNITES AND CONTINUES TO BURN FOR AT LEAST 5 SECONDS

Specific heat is the amount of KCals needed to raise the temperature of 1 kg of oil by 1°C.
The unit of specific heat is KCal/kg°C. It varies from 0.22 to 0.28 depending on the oil specific gravity.
The specific heat determines how much steam or electrical energy it takes to heat oil to a desired temperature. Light oils have a low specific heat, whereas heavier oils have a higher specific heat

The calorific value is the measurement of heat or energy produced, and is measured either as gross calorific value or net calorific value.

The amount of sulphur in the fuel oil depends mainly on the source of the crude oil and to a lesser extent on the refining process.

A diesel fuel is any fuel suitable for burning in diesel or compression ignition engines.
Petroleum diesel fuels may be distillates or blends of distillates and residual fuels.
Two main grades of diesel fuel are marketed in India, High Speed Diesel (HSD) and Light diesel oil (LDO). The former is a 100% distillate fuel while the latter is a blend of distillate fuel with a small proportion of residual fuel.
HSD is normally used as a fuel for high speed diesel engines operating above 750 rpm
LDO is used for diesel engines, generally of the stationery type operating below 750 rpm

A dark viscous residual fuel obtained by blending mainly heavier components from crude distillation unit, short residue and clarified oil from fluidized catalytic cracker unit.
Bunker fuel, furnace oil , Fuel oil are other names for the same product
Furnace oil in the current marketing range meets Bureau of Indian Standards Specification IS : 1593 – 1982 for fuel oils, grade MV2.

ACCEPTANCE OF FUEL OIL FROM SUPPLIER AND CONTROL OF ITS QUANTITY AND QUALITY
UNLOADING OF OIL
KEEPING FUEL OIL IN STORAGE TANK AT THE REQUIRED TEMP.
UNINTERRUPTED DELIVERY OF FUEL OIL TO BOILER BURNERS