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Marine Fuel Watch

IMO 2020 special edition

Marine Fuel Watch

IMO 2020 special edition


Supporting the marine industry

Innospec is the world's largest supplier of marine fuel additives. As market leaders, it's our job to stay one step ahead of the issues fuel suppliers and fleet operators face when handling new fuels or fuels of varying quality. We have many years' experience working in the industry and continually invest in research and development. Our scientists have developed many of the technologies that now set the benchmark for fuel additive performance.

Our commitment to understanding and anticipating future challenges, particularly the drive to reduce emissions, has ensured we could support our customers through IMO 2020 and the introduction of VLSFO. Knowing that fuel instability and compatibility would be a major issue, we moved quickly to develop practical, cost-effective and timely solutions to enhance fleet performance. As always, our focus has been on optimizing engine reliability, boosting performance, improving fuel economy and reducing maintenance requirements.

Staying one step ahead

The problems of handling VLSFO are now well documented. Engine damage, blocked filters, poor cold flow performance, un-pumpable storage tanks and fuel separation are all issues commonly reported in ports around the world. The reduction in ship movements caused by Covid-19 has amplified these problems. Pre-treating VLSFO with Octamar™ HF-10 PLUS and Octamar™ Ultra HF is now providing a practical solution.

Biofuels are being considered as possible replacements for today's marine fuels, particularly in older fleets. FAME (Fatty Acid Methyl Esters) Biodiesel, derived from renewable sources, is seen as a potential 'drop in' solution. However, like VLSFO, these fuels present their own set of challenges in a marine environment. Thanks to our in-depth knowledge of biofuel fuel additives, gained over many years, we could ensure Octamar™ HF products were developed from the outset to be 'biofuel ready'.

To find out more about how our fuel additive technology has enhanced fleet performance in 2020 and about the future of marine fuels, download our presentations from a recent Marine Fuels webinar, hosted by Marine Propulsion. Joshua Townley, Innospec’s Market Specialist Marine, presented as part of a panel of experts on Fuel Testing in a New Age and The Future of Marine Fuels as part of Marine Propulsion’s Marine Fuels Webinar Week, November 2020.

To obtain a pdf-copy of the presentations, please complete the form:

Take Action Before Refuelling

More fears over VLSFO instability

Advice from the major fuel suppliers and our own extensive laboratory testing has confirmed that compatibility and stability in VLSFO will be unpredictable. Many of the ISO 8217 compliant fuels will still cause significant issues on-board.

Over 35 ISO 8217 specification compliant fuel samples were tested, using Turbiscan, for stability and compatibility. The results show:

  • 40% of base VLSFO fuels are currently unstable when they are sold
  • 56% of VLSFO fuels become highly unstable when mixed in a tank
  • Incompatibility occurs irrespective of mix ratio (50:50, 10:90, 90:10 etc)
  • 90% fuels pre-treated with Octamar™ HF10 Plus showed excellent stability

Test Results

A sample ISO 8217 compliant fuel is mixed with itself and five other samples in different ratios to test for both stability and compatibility.
All six fuel samples had a high risk of instability. When tested with the same fuel samples treated with OctamarTM HF-10 PLUS every fuel combination tested positive with no risk of instability.

The Turbiscan Reserve Stability test (one of the most widely used tests in marine fuel labs) predicts the likelihood and speed at which a fuel will destabilise and produce excessive sludge. A Reserve Stability Number (RSN) above 3.0 means there is a high risk of instability.

Not all VLSFO is the same

There are vast differences in VLSFO on the market and the quality varies from port to port and batch to batch. Although these fuels are all classified under the same specification, they cannot be stored, handled or heated in the same way.

There are:

  • Vast differences in fuel composition purchased under the same ISO category.
  • The traditional test methods have proven to be poor predictors of stability in VLSFO.

Total engine failure

These images show just what can happen. This VLSFO was supplied well within ISO 8217 specification.

It was loaded into completely clean tanks and fuel system, yet failed within four hours. Total engine failure soon followed. This case is not a one-off. There have been a number of reports of fuel system failure and engine damage when using ‘on spec’ fuels.

Take action now

Receive more information on our advanced fuel additives or tank cleaning range, including product datasheets, presentations or to talk to one of our Technical teams in your region, simply complete your details on the right.

Innospec offers a unique and cost-effective solution

By pre-treating VLSFO you can solve the problem of fuel instability and tank mix incompatibility. Octamar™ HF-10 PLUS and Octamar™ Ultra HF are the only additives that protect against both distillate sludge and asphaltene sludge.

Octamar™ HF-10 PLUS

Octamar™ HF-10 Plus keeps your engine running by stabilising fuel blends and reducing sludge formation.

  • Improved compatibility when using new fuels or unknown fuels.
  • Safer fuel changeovers for ECAs.
  • Stable and homogenous fuel ensures improved combustion.
  • Reduced sludge means more fuel to burn.
  • Higher treat rates combat injector fouling.
Octamar HF10 plus performance comparison

Octamar™ Ultra HF

Octamar™ Ultra HF provides a complete solution for VLSFO. It keeps your engine running by improving fuel blend stability and combustion while reducing soot formation.

  • Combined combustion and ignition benefits from one additive.
  • Cleaner running from powerful additive technology.
  • Improved fuel economy and reduced fouling of exhaust gas systems.
  • Increased fuel stability and compatibility of marine fuel blends.

Full test results

The Turbiscan Reserve Stability test (one of the most widely used tests in marine fuel labs) predicts the likelihood and speed at which a fuel will destabilise and produce excessive sludge. A Reserve Stability Number (RSN) above 3.0 means there is a high risk of instability.

Our laboratories have tested a number of compliant fuels for stability and compatibility. The tables opposite show the results of six samples of ISO 8271 compliant fuel mixed with itself and five other samples in three different ratios, tested using Turbiscan for both stability and compatibility. The tables show all the results. All combinations of the fuel samples had a high risk of instability. When tested once treated with OctamarTM HF-10 PLUS every fuel combination tested positive with no risk of instability.

Beware of making an expensive mistake

The cost of VLSFO instability is not just a full tank of fuel. Returning the vessel to port, repairing and cleaning the engine system and refuelling can run into many hundreds of thousands of dollars, before you even factor in operational losses.

Take action before refuelling

Claims against fuel suppliers are rarely successful if their fuel meets specification. The oil majors have also made it clear they will not take responsibility for fuel stability after a fuel’s expiry date. This rests squarely with ship operators. So, for the operators’ peace of mind and significantly improved fuel stability, pre-treating fuel with Octamar™ HF-10 PLUS or Octamar™ Ultra HF is the only solution.

Prevention is the only cure

Pre-treating fuel with Octamar™ HF-10 PLUS or Octamar™ Ultra HF is highly effective at stabilising VLSFO. However, it will not reverse sludge formation. Once a fuel has chemically broken down there is no way to reverse the process.

What’s causing the problem?

To reduce the level of sulphur in fuel, VLSFO typically contains up to 90% distillates. This has been demonstrated through SARA analysis.
These distillates most likely come from secondary refining streams to reduce cost and they are highly unstable, more susceptible to aging and prone to rapid oxidisation, especially when mixed or heated. The result is a type of sludge formation that is very different from traditional asphaltene sludge. To stabilise it requires a different sort of chemistry.

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Industry Insights

VLSFO Field Issues

Since mid-November there has been more and more vessels loading IMO 2020 compliant VLSFO, and particularly in December vessels have been starting to consume this fuel as their ROB of HSHFO is depleted. There have been numerous reports of issues encountered during changeover as the crews onboard learn to deal with these new fuels, however not all issues are related to fuel handing onboard and are due to the chemical nature of the fuel.

VLSFO Insights

As global market leader in marine fuel testing and bunker quantity surveys, Veritas Petroleum Services (VPS) has tested the most VLSFO samples in the market to-date and has witnessed first-hand what these very-low sulphur fuels have to offer. Based on this data, VPS is introducing VLSFO Insights a monthly subscription-based service, where technical expertise is combined with its proprietary database of fuel oil and distillate samples, to derive special insights for its users.

Guidance on the development of a ship implementation plan for the consistent implementation of the 0.50% sulphur limit

What next as MEPC 73 rejects proposal for an IMO 2020 experience building phase?

Certain flag states have been calling for an experience building phase based around safety concerns of an unknown fuel, some are saying it is a thinly veiled attempt to delay 2020.

IBIA welcomes IMO’s 2020 preparatory advice for ships

Guidance on ship implementation planning approved by the IMO last week will assist ship owners in preparing for the use low sulphur fuels to comply with the 2020 sulphur limit.


A number of newsletters will be produced to provide more information around how to prepare for IMO 2020 in the most cost effective method. Download the latest here, or register for free copies below.

Technical Bulletins

Innospec is at the forefront of developing fuel additive technology for a changing world.

Our focus is on supporting the fuel industry as it adapts to new opportunities and challenges. By leveraging our experience and expertise in different markets, we create the reliable, highly functional and extremely competitive packages our customers demand. Our strength is our knowledge of fuel and how to improve fuel performance for different applications.

This always keeps us one step ahead of our competitors. Our products are tried and tested in many different environments whether at sea, on the road or in the air. With a worldwide network spanning 23 countries and 2000 employees, we can deliver global solutions geared to local customer needs.

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