Future-proofing for fuel systems

27 Mar 2011
Owners should guard against ‘bad fuel’ when bunkering

Owners should guard against ‘bad fuel’ when bunkering

Under scrutiny from regulatory, legislative and environmental bodies, as well as consumer groups, the pressure remains on the shipping industry to address the continuing challenge of delivering against fuel emission regulations. Martin Lucas, managing director, Kittiwake Developments, looks at the impact of this challenge on onboard fuel systems.

The initial focus has been geared towards emissions reduction in coastal and port areas, and emission control areas (ECAs) continue to widen, with North America primed as the next ECA to be introduced in 2012. The regulatory timetable and targets to reduce SOx (sulphur oxide) and NOx (nitrogen oxide) is daunting for many in the industry. Not just from a cost perspective due to the high price of distillates, but also concerns over supply and demand as well as technical issues, such as engine and fuel system damage that can arise when using low sulphur products.

For example, low viscosity in fuel can lead to a wealth of issues, including reduced lubricity resulting in sticking and failure of the fuel pump, fuel leakage and a loss of capacity in the fuel supply and circulation pumps. One solution is to install special fuel injection pumps, such as tungsten carbide coated pumps, or a fuel pump lubrication system. To help keep the viscosity above the minimum specified value, installing a fuel cooler at the fuel injection pumps can keep the fuel temperature below 40°C and a gradual change over to prevent thermal shock.

Incompatibility of fuel mixtures is another related issue that will rapidly cause clogging of fuel filters and separators sticking of fuel injection pumps. Compatibility should be tested when bunkering heavy fuel oil and low sulphur fuel to give early warning of impending problems. All of these side effects of low sulphur fuel can cause a loss of power and even shut down as we have seen off California in recent years.

Switching between different fuel types can compromise a vessel’s fuel systems and power, and it is essential to check the suitability of each component in the fuel combustion system of each engine and boiler against the range of fuels that you expect to use. Preparing fuel changeover and operating procedures will help to arm you against the real danger of damage to auxiliary machinery, engines and boilers and their components, and a lack of required power being available. The worst-case scenario is a loss of propulsion and therefore being unable to generate power at critical times while maneuvering the vessel can place the ship and environment at risk.

So how can you prevent switching issues, and how can ship operators meet regulatory standards and maximise environmental efficiencies without compromising their fuel systems and performance?

Conducting a thorough evaluation and risk analysis to cover your entire fuel system and components including consulting the relevant manufacturers, is good practice, as well as training crew on the appropriate procedures. Maintaining systems, particularly seals and gaskets, will prevent leakage from low viscosity fuel and consulting your fuel suppliers to ensure the quality of products being used should all be considered as standard. Finally, for safety reason any fuel switching should be completed before entering ports or ECAs.

Ultimately, avoiding damage to pumps and injectors is wholly achievable. To maximise effectiveness, onboard condition monitoring is a prerequisite and central to identifying problems at a very early stage, along with the testing of bunker samples, which is becoming increasingly important as incidents related to ‘bad fuel’ seem to be on the rise. Little attention has been paid to the quality of cutter stocks, which has led to growing concerns over fuel quality, and the global economic downturn has led to a squeeze on the quality of ships personnel, notably chief engineers. In conjunction with this, operational cost cutting measures have undermined robust condition monitoring practices to the extent that ‘bad fuel’ can be said to have as much to do with poor handling as a sub-standard product.

The requirement for ships to carry a MARPOL sample, and operational downsides of using low quality fuel, as well as the commercial consequences of a bunker dispute, have all placed renewed emphasis on the need for best practice, as the financial and operational costs of lower-quality fuel can be very severe. Using the IMO’s revised guidelines on how to collect the sample are the best starting point, but to avoid mistakes, suppliers of sampling equipment such as Kittiwake’s bunker sampling storage systems, provide abridged versions with instructions and advice, making it much easier for the crew to sample correctly.

When it comes to fuel testing, inaction is not an option. Enforcing best practice during the bunkering operation to ensure that a representative sample of the fuel is obtained is the first step. This can then be stored for future reference in case of problems and tested on board the vessel for a number of key parameters. Onboard testing is the ideal solution, and modern testing equipment is quick to operate and will provide very accurate results for water, density, viscosity, salt, compatibility, as well as stability. An advantage of onboard testing is that results are available immediately and before the fuel has to be used. In the event of problems it is therefore possible to mitigate the eventual cost, a very good position in instances of legal actions and liability. To back up onboard testing, onshore laboratory testing is a great ‘insurance policy.’ Kittiwake’s sampling services and those from the likes of FOBAS and DNV provide both test results and thorough analysis. Should problems arise, they are on hand to provide detailed technical support that is often beyond the capabilities of a hard-pressed marine superintendent.

Combining best practice with effective monitoring techniques is central to ensuring you are on the front foot when it comes to maintaining your fuel systems, particularly in the current regulatory climate. But there needs to be a change in mindset. Complying with emissions regulations must naturally be a minimum standard to adopt, but monitoring and fuel testing must be seen as key to operational – as well as regulatory - success and the foundation for maintaining high performance standards, driving further efficiencies, as well as maintaining competitive advantage.

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