The actual Bunkering operation is carried out with bunker checklists. In this article, emphasis is made on the checklists, safety precautions, SOPEP locker & SOPEP equipments, temperature & density correction to calculate the quantity of oil bunkered. Formula for calculation has been included.
Bunkering Oil
Earlier we learnt about bunkering and what is the means. Now we will study the process of actual bunkering operations and the practical details of the process of bunkering oil. All types of ships needs fuel oil, lub oil etc and hence it is important for everyone to understand the actual process of bunkering.
Pre-bunker preparations.
The most important aspect of bunkering operation is the “checklists”, which forms a part of company’s safety management system (SMS) and I.S.M.,eliminating the possibility and negligence of human and other operational errors. The pre-bunkering checklist must be followed in-consultation with the Chief Engineer(C/E), as he is the person-in-charge for the bunkering operation. Before bunkering, ususally it is 4th engineer officer , taking “soundings” of bunker tanks and calculates the volume of fuel oil available in every fuel oil tank of the ship. Then a Bunker-plan is made to plan the distribution of total quantity of bunker fuel oil.
Bunker Procurement
Ordering of Bunker oil:
The ship Managers (superintendents) monitor the performance of a fleet of ships. For eg. On owning a car, we tend to keep a check on its fuel consumption widely called as “mileage”. It is the distance travelled by the vehicle for a unit volume of fuel used. In the same way, as the ship consumes humungous quantity of fuel, whose costs are forming the major part of ship’s operation, The Managers tend to keep a check on it. This is measured in terms of specific fuel oil consumption of the main propulsion engine.
On knowing the fuel oil consumption for a day & next voyage plan, the quantity of fuel oil required is calculated and compared with the available bunker tank capacity. A requisition is placed through the C/E & Master of the vessel to the Managers. The requisition is processed and evaluated for the quality & quantity of fuel to be supplied for the particular ship. Planning is done for the delivery of bunker at a particular port where the oil is available at a comparitive lesser cost. On taking all these aspects into consideration, the Managers, deliver bunker to the vessel. Upon receiving the bunker, a sample collected during bunkering operation is sent for lab analysis to confirm the delivered oil meets the required standard for the safe & efficient operation of the auxiliary engine & main propulsion engine.
Pre-Bunker Checklist:
Pre-Bunkering Procedure:
- State of adjacent waters noticed
- Vessel properly secured to dock
- Check suppliers product corresponds to ordered product
- Agree quantity to be supplied
- Check valves open
- Day tanks full and supply valves closed
- Warning signs in position e.g. No Smoking
- SOPEP plan available
- Clean up material in place
- Oil Boom in place
- Foam fire extinguisher placed at bunker station
- Alfa Laval and transfer pumps off
- Fuel tank supply valves open
- Agree stop/start signals between vessel and barge/truck
- Bravo flag flying/red light showing
- Agree pumping/transfer rate
- Agree emergency shut down procedure
- Specification sheet received
- Check hose and couplings are secure and in good order
- Fuel nozzle and hose secured to vessel
- Check barge/truck meters Reading:
- Check on board meters Reading:
- Bunker Valve open
- Unused manifold connections blanked off
- Master informed
- Signal pumping to commence
The above checklist has to be completely filled religiously by both the ship & barge personnels. Please move on to the next page by clicking below
SOPEP equipments
At the bunker manifold and wherever necessary, as per the ships SOPEP plan, the SOPEP equipments should be kept in immediate readiness in order to avoid oil spill/pollution during bunkering operation.
SOPEP- Shipboard Oil Pollution Emergency Plan.
The SOPEP Locker must have minimum of the below specified items:
- absorbent roll
- absorbent pads
- absorbent granules
- absorbent materials
- brooms
- shovels
- mops
- scoops
- empty receptacles (200 ltrs capacity)
- portable air driven pumps
- oil boom
- oil spill dispersants.
These items must be stowed in an easily accessible locker, clearly marked, and is to be brought on deck ready for immediate use, prior to all oil transfer operations.
During Bunkering Procedures:
During Bunkering checklist:
- Witness taking and sealing of 2 representative product samples
- Monitor fuel connections for leaks fuel flow and control tank levels
- Change over of tanks whenever necessary.
- Checking the rate at which bunkers are received.
- Checking the tightness/slackness of mooring ropes.
- Checking trim/list of the bunker barge & the ship.
- Continuous monitoring/look outs for the vessel’s position(when at anchor).
During bunkering, the above checklist must be filled up and continuous monitoring of the above secified items are required till the bunkering operation is complete.
After Bunkering Procedures:
On completion of the bunkering operations, with the ship-barge co-ordination, the line should be blown with air to make sure the line is not filled with oil. The after-bunker checklist is followed.
After Bunker Checklist:
- Bunker Valve closed
- Disconnect hose (drain before disconnecting)
- Check barge/truck meter Reading:
- Check ships meter Reading:
- Sign Bunker Delivery Receipt BDR No: (Bunker Delivery report/Note).
- Retain BDR with product sample
- SOPEP plan returned to bridge
- Clean up gear stowed / Oil boom returned
- Bravo Flag/Red light stowed/switched off
- Remove and pack away warning/safety signs
- Foam fire extinguisher placed back in correct location
- Complete Oil Record Book
- Master informed of completion
- Confirm in Oil Record Book Bunkering checklist completed
Quantity Calculation & Temperature-Density Correction:
After bunkering of various fuel oil tanks, the quantity in each bunkered tank must be calculated to cross-check whether the received quantity of oil matches the requisition. For calculating the quantity, “sounding” of the tanks which are “bunkered” must be taken. The “Density” of the fuel oil supplied vary from place to place. It also varies with the temperature. As a thumb rule, the density of fuel oil decreases with increase in temperature. So, when the oil is supplied at a higher temperature, then the volume of oil supplied is less than what is supplied at lesser temperature.
Oil Temperature —————————-Density ——————————- Volume Of Oil Supplied
Increases————————————–Decreases————————————Lesser
Decreases——————————— —Increases ————————————-More
Also the formula which is generally used for temperature-density correction is as follows:
MT= {(t1-15)*0.00065}*volume of oil in m^3.
where MT stands for metric tonnes.
t1 stands for temperature of oil in bunker tanks in degree celcius,
0.00065 is the correction factor,
volume of oil in m^3, is obtained from the sounding table.
Safeties:
General Safeties During Bunkering:
- SOPEP locker,
- Emergency shut-down arrangements,
- Bunker line over-flow arrangements to overflow tank with audible & visual alarm,
- Relief valve in the bunker line,
- Containment trays.
- Consistent & Continuous look outs.
BDN & Related IMO Regulations for Bunkering:
Bunker Delivery Note (BDN):
– Becomes a Statutory document
– Must be kept on board for 3 years for inspection and a copy may be taken for further examination by PSC.
– Must contain all data required by Appendix V
– Name and IMO number of vessel Port
– Date of Commencement of delivery
– Details of fuel oil supplier
– Product name, quantity , Density at 15 0C and Sulphur content % m/m
– A declaration that fuel supplied meets Regulation 14 and 18 requirements
Fuel Oil Sampling
– A sealed sample meeting the requirements in associated guidelines has to supplied to the ship by the bunker supplier
– For each individual BDN a sample has to be taken at the vessel’s bunker receiving manifold. (see procedure in associated guidelines) – ISM Manuals.
– The sample label has to be signed by both the bunker supplier’s representative and the vessel’s Chief Engineer.
– The sample size shall be not less than 400 mls
– The sample is not to be used for any commercial purpose
– The sample is to be retained on board for at least 1 year for inspection by PSC as required
Shipboard Procedures for BDN and Samples
- Adequate bunker manifold location for sampler attachment
- External safe storage location for samples for 1 year period
- Log book for sample retention and custody transfer
- Safe storage for BDNs and other documents relating to bunkering onboard
- Port/Flag State Control Guidelines
- Proposed Guidelines from FSI 13 for MEPC 53 approval.
- Initial inspections and Primary survey parameters – then “Clear Grounds” for
- in-depth inspections
- “In depth” inspection parameters
- Detainable deficiencies
- Non-Party ship inspections
Conclusion:
Thus bunkering operation is direclty related to “MARPOL” annexes, i.e annex 1 and annex 6. When oil is spilled it causes marine pollution under annex 1. When the bunkered oil doesn’t meet certain specifications, it causes pollution of air which comes under annex 6.
“MARPOL” will be dealt with in the future articles.