Fuel oil

Fuel oil or heavy oil is a fraction obtained from petroleumdistillation, either as a distillate or a residue. Broadly speaking, fuel oil is any liquid fuel that is burned in a furnace or boiler for the generation of heat or used in an engine for the generation of power, except oils having a flash point of approximately 40 °C (104 °F) and oils burned in cotton or wool-wick burners. In this sense, diesel is a type of fuel oil. Fuel oil is made of long hydrocarbon chains, particularly alkanes, cycloalkanes and aromatics. The term fuel oil is also used in a stricter sense to refer only to the heaviest commercial fuel that can be obtained from crude oil, i.e., heavier than gasoline and naphtha.

Types of Fuels

  • MGO (Marine gas oil)
  • MDO (Marine diesel oil)
  • IFO (Intermediate fuel oil)
  • MFO (Marine fuel oil)
  • HFO (Heavy fuel oil)

Standards and classification

  • IFO 380 - Intermediate fuel oil with a maximum viscosity of 380 Centistokes (<3.5% Sulphur)
  • IFO 180 - Intermediate fuel oil with a maximum viscosity of 180 Centistokes (<3.5% Sulphur)
  • LS 380 - Low-sulphur (<1.0%) intermediate fuel oil with a maximum viscosity of 380 Centistokes
  • LS 180 - Low-sulphur (<1.0%) intermediate fuel oil with a maximum viscosity of 180 Centist
  • MDO - Marine diesel oil.
  • MGO - Marine gasoil.
  • LSMGO - Low-sulphur (<0.1%) Marine Gas Oil - The fuel is to be used in EU community Ports and Anchorages.
  • ULSMGO - Ultra Low Sulphur Marine Gas Oil - referred to as Ultra Low Sulfur Diesel (sulphur 0.0015% max) in the US and Auto Gas Oil (sulphur 0.001% max) in the EU. Maximum sulphur allowable in US territories and territorial waters (inland, marine and automotive) and in the EU for inland use.s
  • MDO - Marine diesel oil.
  • MGO - Marine gasoil.
  • LSMGO - Low-sulphur (<0.1%) Marine Gas Oil - The fuel is to be used in EU community Ports and Anchorages.
  • ULSMGO - Ultra Low Sulphur Marine Gas Oil - referred to as Ultra Low Sulfur Diesel (sulphur 0.0015% max) in the US and Auto Gas Oil (sulphur 0.001% max) in the EU. Maximum sulphur allowable in US territories and territorial waters (inland, marine and automotive) and in the EU for inland use.

Marine distillate fuels

Parameter Unit DMX DMA DMB DMC
Density at 15 °C kg/m3 - 890 900 920
Viscosity at 40 °C mm²/s 5.5 6 11 14
mm²/s Min 1.5 - -
Water % V/V - - 0.3 0.3
Sulfur1 % (m/m) 1 1.5 2 2
Aluminium + Silicon2 mg/kg - - - 25
Flash point3 °C 43 60 60 60
Pour point, Summer °C - 0 6 6
Pour point, Winter °C - -6 0 0
Cloud point °C -16 - - -
Calculated Cetane Index 45 40 35 -
Parameter Unit RMA 30 RMB 30 RMD 80 RME 180 RMF 180 RMG 380 RMH 380 RMK 380 RMH 700 RMK 700
Density at 15 °C kg/m3 960 975 980 991 991 991 991 1010 991 1010
Viscosity at 50 °C mm²/s 30 30 80 180 180 380 380 380 700 700
Water % V/V 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5
Sulfur1 % (m/m) 3.5 3.5 4 4.5 4.5 4.5 4.5 4.5 4.5 4.5
Aluminium + Silicon2 mg/kg 80 80 80 80 80 80 80 80 80 80
Flash point3 °C 60 60 60 60 60 60 60 60 60 60
Pour point, Summer °C 6 24 30 30 30 30 30 30 30 30
Pour point, Winter °C 0 24 30 30 30 30 30 30 30 30

The above table is the typical properties of MARINE RESIDUEL FUEL

Maximum sulfur content in the open ocean is 3.5% since January 2012. Maximum sulfur content in designated areas is 0.1% since 1 January 2015. Before then it was 1.00%.
The aluminium+silicon value is used to check for remains of the catalyst after catalytic cracking. Most catalysts containsaluminium or silicon and remains of catalyst can cause damage to the engine. The flash point of all fuels used in the engine room should be at least 60 °C. (DMX is used for things like emergency generators and not normally used in the engine room. Gaseous fuels such as LPG/LNG have special class rules applied to the fuel systems.)