Take Action Before Refueling
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 8271 compliant fuels will still cause significant issues on-board.
Over 35 ISO 8271 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
A sample of ISO 8271 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 Octamar HF-10 PLUS every fuel combination tested positive with no risk of instability.
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 destabilize 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 Octamar HF-10 PLUS every fuel combination tested positive with no 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.
- 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.
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 unique, specially designed additives that protect against both distillate and asphaltene sludge.
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 refueling can run into many hundreds of thousands of dollars, before you even factor in operational losses. Take action before refueling
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 stabilizing 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?
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 oxidization, especially when mixed or heated. The result is a type of sludge formation that is very different from traditional asphaltene sludge. To stabilize it requires a different sort of chemistry.
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.