The maritime industry is currently going through significant changes due to the introduction of tighter emission regulations. A stronger awareness in preserving the environment has pushed forward more stringent International Maritime Organization (IMO) legislation that imposes on ship owners and managers the use of new technologies that affect the day by day running of the vessel, starting with the choice of fuel, through changes in the engine operational parameters, and culminating in a severe reduction in allowable exhaust emissions.
The upcoming change to the permissible sulphur content of marine fuels burnt in the open ocean has brought the subject of compliance to the forefront. The most cost-effective way to meet the 0.5% sulphur limit is to blend the minimum amount of expensive, low sulphur fuel with the maximum amount of cheap, high sulphur fuel. Clearly, this leads to fuels that surf the compliance line very closely.
Of course, the issue of fuel compliance is not just restricted to sulphur. For instance, naval procurement often demands that distillate fuel supplies contain less than 0.1 % biodiesel [1, 2]. Recent technological advances mean that field spectrometers can measure sulphur and biodiesel concentrations within different fuels.
Download our white paper titled "The Science of Compliance" by Dr. David Atkinison to prepare for the upcoming change to the permissible sulphur content of marine fuels.
Unchartered operational territories
Combining these changes with the following factors:
A volatile fuel market,
High competition in cargo rates,
The pressure to reduce operating costs, and
The introduction of new technological advancements
have prompted the marine industry to abandon the ‘comfort zone’ that has been enjoyed for the last 20+ years. Today’s environment has a significant impact in the way two-stroke, slow speed, diesel engines are managed, introducing new challenges for different fuel types, different lubricants and ancillary equipment required to meet the new requirements.
Field experience has shown that all these factors can lead to:
Engine damage caused by poor fuel quality.
Lack of training/knowledge of the operators.
Incorrect lubrication choice.
Poor set up.
Solutions come in many shapes and sizes, from simple, two-minute handheld test kits to state-of-the-art online sensor technology. Through scientific testing, our lead-application engineers have demonstrated that a combination of these tools can deliver real savings by:
Preventing accelerated wear in liners, piston rings, and pistons.
Reducing lubricant costs by optimising feed rates.
Avoiding catastrophic engine damage.
Enabling proactive maintenance scheduling and eliminating costly, unexpected, downtime.
Challenges facing the marine environment
Two-stroke, slow speed, diesel engines are used in the marine industry to power the largest commercial ships currently sailing on the seas. These internal combustion engines are used for their high thermal efficiency, exceptional reliability and ability to use a variety of fuel types including residual oils. These fuels are, broadly speaking, the very end product of the crude oil refining process and are commonly referred to in the marine industry as Heavy Fuel Oil (HFO) or Residual Fuel Oil (RFO). These fuels are regarded to be the most cost-effective available; for this reason, they’re the preferred choice to power main engines and generators in large, ocean-going, vessels. HFO comes in several grades; the best and most expensive grades have the lowest Sulphur content.
Choosing HFO, however, presents challenges in dealing with the varying sulphur contents in:
Significant water content.
The potential presence of abrasive aluminum silicate compounds.
These materials are carried over from catalytic cracking during the crude oil refining process and are referred to as catalytic fines or simply, ‘cat-fines’. The International Standards Organization has published a specification for marine HFO (ISO 8217:2010) which imposes upper limits on these, and other fuel parameters to provide consistency in the market. Nevertheless, bunkered HFO, even when conforming to these specifications, requires further onboard processing to reduce the water and solids contents to levels deemed acceptable for engine operation.
Regulations present challenges to operators
In the marine industry, environmental regulation is on the increase and operators are facing new challenges that threaten their cash-tight budgets. But it is not just the added cost of more expensive alternative fuels or lubricants that can impact operators, critically, it is also the effect that these changes have on the operating conditions of the vessel, leading to unexpected damage and causing unplanned downtime.
With such stringent and widespread regulations, compliance with the rules becomes even more challenging. New operating methods and procedures for fuel changeover, oils, and equipment required for compliance can indeed lead to unintended consequences such as damage caused by out-of-specification fuel or incorrect/insufficient cylinder lubrication.
Amidst the omnipresent drive for safety and operational efficiency, effective condition monitoring tools and techniques have never been more valuable in helping operators manage, avoid or mitigate these costly issues.
The proper combination of condition monitoring techniques provides a wealth of information, allowing ship operators to take immediate corrective actions to mitigate any damage, to allow continued, efficient operation and prevention of the high costs associated with undetected liner wear events. The savings associated with these early warnings far outweigh the cost of the condition monitoring tools used to detect them.
Download the white paper and learn how the combination of offline and online condition monitoring techniques can be successfully used to prevent engine damage and avoid unplanned maintenance costs due to downtime.
Article contributed by Dr. David Atkinson, principal chemist, Parker Kittiwake, part of Parker's Hydraulic and Industrial Process Filtration Division.