Furnace Oil is one of the cheapest fuels available for industrial use. It is a by-product of petroleum refineries. While processing the CRUD Oil, FO ( Furnace Oil ) is one of the products along with other petroleum fuels like HSD, Petrol etc.

Typically it has a calorific value as 10000 cal/gm. The furnaces which are used mainly for heating or pre-heating a large quantity of metal, are the main users of FO. This can be stored in vertical as well as horizontal tanks, above ground or even underground in some cases. The dimensions and capacities of these tanks are predefined in India by CCOE, which is the regulating body for fuel storages.

For direct burning, FO is viscous as well as not suitable for complete combustion. It is pre-heated to 55 degrees Celsius onwards, depending upon application. The flow increases with temperature and it improves the combustion also. A water based scrubber is used in the exhaust chimney of furnace, which arrests considerable amount of carbon suite and improves the emissions.

The entire FO yard, as per IS standards, pre-heating in storage tanks as well as pipes& Pumps etc, pumping station, level controls, control-panels and entire distribution pipeline is designed taking into consideration the application, required capacity of storage, logistics, available space and government norms.

Uses of Furnace Oil are :

  • As fuel for Power Generation in DG Sets
  • As fuel for Boilers/ Furnaces/ Air preheater/ Any other Heaters
  • Fuel for Bunkering
  • Fuel/ Feedstock in Fertilizer Plants

Benefits

  • Cheapest petroleum fuel available – gives most heat per litre at lowest cost.
  • Readily stored – occupies half the space of coal for equivalent heat content.
  • Easily handled, regulated and controlled.
  • Less maintenance than coal-fired equipment.
  • Less labor required than with coal, no stoking, ash removal or conveyors required.
  • Less capital expenditure than equivalent coal plant.
  • Clean operation – no fly ash or dust problems, easy smoke control.
  • Longer furnace and boiler life; less depreciation.

Typical Furnace Oil Specifications (Indian standards IS:1593–1982)

S.No.
Characteristic
Requirement For
Method of Test
Grade LV
Grade MVI
Grade MV2
Grade HV
Ref to [P : ] of
IS : 1448*
(1) Acidity, inorganic Nil P : 2
(2) Ash, percent by mass, Max 0.1 P : 4
(Method A)
(3) Gross, calorific value Not limited, but to be reported
(See Note 1)
P : 6
(for reference) and
P : (for routine)
(4) Relative density at 15/15°C Not limited, but to be reported
(See Note 2)
(5) Flash point, [Pensky martens (closed)], Min 66°C P : 21
(6) Kinematic viscosity in centistokes at 50°C, Max 80 125 180 370 P : 25
(7) Sediment, percent by mass, Max 0.25 P : 30
(8) Sulphur, total, percent by mass, Max
(See Note 3)
3.5 4.0 4.0 4.5 P : 33
(for reference)
and P : 35
(for routine)
(9) Water content, percent by volume, Max 1.0 P : 40

NOTE 1: Normally the gross calorific value is of the order of 10,000 cal/g.

NOTE 2: Fuel oil for marine uses in diesel engines shall not exceed a limit of 0.99.

NOTE 3: Recognizing the necessity for low-sulphur fuel oils in some specialized uses; a lower limit may be specified by mutual agreement between the purchaser and the supplier.

Effective 01.04.10 FO/LDO supplies to rail fed customers is through BTPN (8 wheeler) rakes only since railways has withdrawn conventional (4 wheeler) rakes from circulation.