The term “Bunkers” refers to either the fuel oil used by ocean going ships or the tanks they are stored in. It is derived from an historic reference to coal bunkers used in the days of steam and sail. The great majority of the bunker fuels used by the world’s merchant fleet are residual fuel oil. This is also true for the vast majority of large diesel engines operated on land. By definition, residual fuel oils are the products remaining from the refinery processes after all the distillate or lighter fractions have been removed.
Bunker fuel is delivered by pipeline, boat or barge. One common theme is that the world of commercial marine fuel supply is totally separate from the world of recreational marine fuels. Shipping has a higher volume and low-cost incentive to arrange deals with refiners to produce tailored marine fuels that are most cost effective for their engines. They use fuels that involve less refining (leaving the sulphur in the fuel), nd therefore lower cost than other fuels.
For ocean going ships and to a large extent, land based users also, the type of fuel depends on three things:
Engine design and fuel system used
Cost of the fuel
Availability in the bunker port
Sulphur content (where restricted for operation in Emissions Control areas)
Bunker Fuel Terminology
There are two basic types of marine fuels — distillate and residual. A third type is a mixture of these two, commonly called “intermediate”. Distillate fuel is composed of petroleum fractions of crude oil that are separated in a refinery by a boiling or “distillation” process. Residual fuel or “residuum” is the fraction that did not boil, sometimes referred to as “tar” or “petroleum pitch”. Fuel for marine use in engines and boilers has the following types and grades:
Fuel Type & Fuel Grades Common Industry Name
Distillate DMX, DMA, DMB, DMZ Gas Oil or Marine Gas Oil
Intermediate IFO 180,IFO 380, Marine Diesel Fuel or Fuel Oil
Residual RMA-RML Fuel Oil or Residual Fuel Oil. visit this website. https://versenergy.com