

In simple words Vessel bunkering means refueling of a ship, aero-plane or any huge equipment that would require refueling.
Of course there are two things to be noted, firstly being a marine site we would be mainly concerned about bunkering in context of ships and marine vessels. Secondly bunkering also refers to loading other items like lubricating oil etc but we will mainly focus on fuel.
Unlike the simple procedure that we under go on a daily basis at our refueling station, vessel bunkering is a much more complicated procedure due to the large amount of fuel, lubricants and large size of equipment that are required to bunker vessels. As easy as it may seem, on board huge vessels this procedure it taken very seriously to avoid any accidents that could spell disaster.
There are strict procedures and protocols that are in place before the operation begins, and during the bunkering process, to prevent pollution, maintain safety of personnel as well as the vessel it self. The procedure of vessel bunkering is usually broken down in to four main areas
- Pre-delivery procedure
- Wastage due to spillage procedure
- Safety precautions in place
- Sampling of bunkered fuel.
Procedure of Vessel Bunkering:
Pre Delivery:
This is the first process conducted to estimate the required fuel, quality and type of fuel and lubricants. This is done in advance and details collected are sent to the refueling hub in order for them to keep fuel matching the vessels specifications ready. It also helps to save time at the fueling port since bunker ports charge vessels high rates for using there facilities as a revenue source.
Spillage prevention:
In this procedure measure are taken to avoid spillage of fuel during the bunkering process that can lead to accidents occurring or pollution of the harbors, ports or surrounding areas that bunkering is taking place.

Safety precautions:
As at any refueling station safety is the first priority. Mostly done to avoid fire, in vessel bunkering there is a protocol that is to be followed strictly.
This part of the procedure is the longest and last through out the bunkering process. Personnel are posted at different positions like the fuel tank to keep checking the fuel level, inlet valve incase of emergency shutoff and other designated areas of the vessel.
All over flow and breather pipes are cocked to prevent spillage, oil absorbent is kept at designated places in case of any oil spill, foam fire extinguishers also to be checked and places at these points, smoking, welding or any work that requires heat or flame to be stopped, keep checking oil levels during bunkering process, stop pumping fuels a few minutes before tanks fill to let fuel in pipe drain and also to avoid sudden high pressure after valve is closed that could cause the pipe to burst.
If possible take slightly less fuel than tank capacity to avoid spillage occurring. Last but not least register the amount of fuel on the ship on the fuel logbook.
Sampling of bunkered fuel:
This is to be done before, during and after the bunkering process to confirm that the fuel specifications are correct for the vessel, since wrong fuel could spell disaster for the ship and its crew while sailing in the open seas. Fuel that is wrongly specified to a ship can cause the engine to over heat in turn coursing fire within the ship while at sea, it may also have other effects like thickens when the ship sail to colder regions of the globe like Antarctica or frozen oceans thus stalling the ships operations.
Excessive expansion due to heating could also cause spillage resulting in marine pollution. After the bunkering process is complete, a delivery receipt should by issued to the vessel stating details of viscosity, density, water content, delivery temperature? This receipt should be stored safely as it may be used as a reference at a later stage.
References:
- The Business of Shipping by Lane C Kendall, James J Buckley
- Ship coal bunkering facilities by Joel S Greenberg, David. T. Parmer