Ships operating in Emission Control Areas (ECAs) are subject to the international regulation MARPOL Annex VI – “Prevention of Air Pollution by Ships”, while other local regulations worldwide also have their own limit requirements for sulphur emissions from ships (eg. EU Ports, China ECA, Hong Kong & Taiwan, etc.).
When entering the designated regions, vessels are required to change fuel oil in order to comply with the sulphur limits. This means that, before entering an ECA, the crew should conduct a fully changeover procedure to a compliant fuel oil with reduced emissions of Sulfur Oxides (SOx), preventing air pollution caused by maritime activity.
So what is the best practice for a safe Fuel Oil Changeover?
Fuel Oil Changeover in Main Engine
Outside ECAs, most ships operate by using high sulfur fuel oil (HSFO) which is much cheaper but more pollutant than low sulfur. By the time they enter a designated area, it is inevitable that they change fuel oil with lower content of sulphur.
This changeover should be followed by the right manipulations taking into consideration the right place and the right moment, to prevent any unfavorable loss of the expensive low sulfur fuel.
At this process, the crew is guided by the LSF calculator. All modern ships carry a Low Sulfur Fuel (LSF) calculator which is used to indicate the accurate time that the changeover should commence, by the time the vessel approaches an ECA.
Since the calculator indicates the accurate time, there are some items to be checked prior to the changeover procedure:
- All fuel tanks must be ready for the procedure.
- The separator should be used with in accordance with the activity of tank operations.
- The LSFO should be filled into settlings and service tank as per the quantity calculated in the voyage plan for the specific ECA.
Fuel Oil Changeover in Auxiliary Engines and Boiler
Auxiliary Engines and Boilers should also follow the changeover procedure of Fuel Oil. Concerning the auxiliary engines, the changeover should take place at load. The actions to be followed are:
- Close the fuel oil heaters
- At the right temperature, open the diesel valves
- Close the heavy oil return when the system is flushed
An equivalent procedure should be followed for the boilers during the changeover procedure.
Dangers that may occur during change over
The most challenging issue in this procedure is to keep the stages of changeover as per manufacturers’ guidance, taking into consideration that the different fuel may lead in pumps scuffing and/or main engine failure, an event which may cause further incidents at sea.
An additional reason of conducting the operation safely is the Port State Control inspection that may occur both at port or at sea (with the use of drones) in order to verify compliance with sulfur limits.
Fuel Oil Changeover Procedure must be followed by record keeping of every action and activity concerning onboard procedures and fuel quantities should be written down, determining that requirements are followed as demanded.
The crew should keep the level of the existing fuel right before changeover begins. Additionally, the ORB and Engine Logbook should be completed containing all necessary information of the process, such as the date, time and position of the ships during operations.
Bridge and engine logbook should be completed as required in order to provide information for time (start/completion) and position of the operation. Note that the completion position should be just out of the limit of designated area.
It becomes understood that it is necessary the crew to be well-trained and adequately familiarized with changeover process, in order to cope with the potential challenges involved.
For safety of crew members and the effectiveness of operations during fuel oil changeover, operators should accordingly invest in the training of shipboard staff, raise awareness for the risky situations and keep them updated for any amendments concerning Fuel Oil Management and Changeover.
SQE has developed a sample of toolbox meeting in order to be used as guidance onboard.