EU Sulphur Directive
Members who trade their vessels to European ports will be aware that Article 4b of the EU Sulphur Directive (2005/33/EC) is due to enter into force on 1 January 2010. As of that date, ships berthed or anchored in EU ports, and all inland waterway craft, will not be permitted to consume marine fuels with a sulphur content exceeding 0.1% by mass. Similarly, Member States must ensure that marine gas oils marketed within their territories comply with the 0.1% sulphur limit by the same date.
The provisions do not apply to vessels scheduled to be at berth for less than two hours in accordance with published timetables, hybrid sea-river craft at sea if they hold a certificate proving conformity with SOLAS and ships which switch off all engines and connect to shore power while in port. The Directive also names a number of ferries operating exclusively in Greek territorial waters which have been granted a temporary derogation until 1 January 2012.
Main and auxiliary boilers are generally designed to run on heavy fuel oil (HFO). However, HFO with a maximum sulphur content of 0.1% is currently unobtainable. Switching to low sulphur gas oil is therefore the only practicable alternative at present.
Using low sulphur gas oil in a boiler designed to run on HFO may trigger an explosion unless appropriate modifications are made in accordance with manufacturers’ recommendations. Additional precautions should also be taken. Lloyd’s Register has published the following advice:
• Boiler and fuel system manufacturers should be consulted for fuel switching guidance and to confirm that the boiler, combustion control systems and associated fuel system components, such as pumps, are suitable for the intended types of fuel.
• The furnace purge process must be functioning correctly. It is essential that the whole of the furnace space is fully purged before re-lighting any fires.
• Burners, in general, and tips, in particular, must be appropriate to each type of fuel to be used.
• The spark igniters (or equivalent) must be correctly functioning and positioned so as to readily ignite the fuel spray on start up.
• All boiler flame detection and related safety systems must be operating correctly. In the case of flame detectors, they must be correctly positioned to pick out the particular flame pattern which is encountered with the types of fuel to be used.
• Manual and automated combustion control system functions should be checked as necessary to ensure they are operating correctly and reliably.
• Due to their searching nature, the use of gas oil fuels in systems which have generally previously operated with HFO can result in seepage of fuel from pipe flanges, equipment seams and other fittings.
• To ensure the minimum quantity of carbon deposition material within the combustion and uptake spaces, soot blowers should be operated at the latest possible opportunity before entry into coastal and port waters.
• The boilers, burner and fuel oil system, including the relevant automatic controls, should be reviewed by means of a HAZOP workshop, through which the action points for the operators and manufacturers can be identified. (A HAZOP workshop is the preferred approach. However, a suitable risk assessment may be undertaken by the system designer(s) and/or manufacturer(s) provided the results are distributed to all stakeholders for comments.)
• Oil fuel burning arrangements must be in accordance with the rules of the relevant classification society.
Lloyd’s Register points out that the above list is not exhaustive.
Machinery, Equipment and Systems
Machinery, equipment and systems other than boilers may also need to be modified. Germanischer Lloyd’s guidelines state:
Fuel Oil Supply System (eg pipes, pumps, cooler/heater, fuel oil booster systems):
• The fuel oil supply system must be in compliance with the fuel change over procedure as specified by the engine and boiler/burner manufacturer for the relevant fuel grades.
• For low sulphur distillate oil (LSDO) a fuel oil cooler is recommended.
• For existing pumps loss of delivery pressure at low viscosities is to be expected.
• Additionally installed fuel oil supply systems have to comply with the class requirements for unattended machinery spaces in terms of alarms, redundancy and stand-by pumps.
• Fuel return lines have to be considered to avoid possible contamination of low sulphur fuel by other fuels.
Main Propulsion and Auxiliary Engines at Berth (normally auxiliary engines only):
• Lubricity: important especially for fuel injection and gear type pumps. The experience of marine diesel engines on LSDO with sulphur not exceeding 0.1% is limited.
• Viscosity: a fuel oil cooler might be necessary in the supply system to achieve the required viscosity for injection.
• The fuel change over procedure may vary from engine type to engine type.
• Operation of the engine and the choice of lubricants have to be in compliance with the engine manufacturer’s specification.
Compliance with Classification Society Requirements
In order to ensure that class is maintained, all planned modifications to boilers, auxiliary engines and associated fuel storage, supply and control systems should be approved by the vessel’s classification society in accordance with class rules. Members are reminded that compliance with classification society requirements is a condition of cover.
Members operating vessels which may be affected by Article 4b of the EU Sulphur Directive but who have not yet taken action are urged to do so without delay. All engine room machinery, equipment and systems should be assessed to ascertain whether modifications may be required prior to using gas oil containing 0.1% sulphur or less. If so, advice should be sought from the manufacturers concerned and their recommendations should be strictly followed. In addition to obtaining class approval, the Safety Management System may need to be amended to take account of any procedural changes. In such cases crew familiarisation and training will also need to be addressed.
An overview of the problems and the risks are set out in a report produced by the AEA Group for the European Commission entitled “Use of distillate fuels by ships at berth”.
The US Coast Guard has issued a Safety Alert on “Avoiding propulsion loss from fuel switching”.The Safety Alert refers to an American Petroleum Institute (API) paper on “Technical Considerations of Fuel Switching Practices”.
In October 2009 a number of presentations on this issue were made at a European Maritime Safety Agency (EMSA) workshop entitled “Technical meeting on the use of 0.1% sulphur content marine fuel at berth under Directive 2005/33/EC”.
Members may also contact the Loss Prevention department if further information is required.