Article by Wolf Rehder, VPS Area Manager Germany

Prevent emergency equipment from failing during an emergency
The lifeboats, emergency generators, and emergency fire pumps onboard are among the vital critical equipment essential for efficient, dependable, and prompt operation during onboard emergencies and across diverse climatic conditions.

Most companies and vessels have procedures in place to monitor their fuel quality. Close attention is paid to the management of fuels to be used in main and auxiliary engines, regardless of fuel-grade, as this has a direct impact on safety, health and the environment as well as on the economic operation of the vessel.

Most companies and vessels also have routines in place to regularly test emergency equipment. Nonetheless, it seems that in numerous instances, there is insufficient focus on the quality of fuel utilised in emergency equipment.

Fuel grade DMX within the ISO8217 specification is specifically intended for use within emergency equipment. However, since this is not a mandatory requirement, marine gas oil (MGO grade DMA) used for other purposes on board, is often used to fill up emergency equipment tanks. This could lead to hazardous outcomes as the DMA grade fuel might not be suitable for its intended use. The quality of the fuel in the emergency equipment tanks may also deteriorate during storage. Hence it is essential to test and ensure that the quality of the fuel being taken into the tanks is ’fit for purpose’ and monitored at regular intervals.

Impact of various parameters on the operation of the emergency equipment
Cold Flow Properties (Cloud Point and Pour Point)
Distillate fuels are predominantly paraffinic in nature and under colder temperature conditions, the paraffins can precipitate from the fuel in the form of wax. As a consequence, this wax can lead to blocked pipework and filters, leading to numerous operational issues including potentially starving the vessel engine of fuel.

Cloud Point (CP) of a distillate fuel is the temperature at which the paraffinic wax begins to separate from petroleum oil and form a cloudy appearance. This is the first indicator of cold-flow issues with a fuel.

Pour Point is the lowest temperature at which the fuel will flow, i.e., the fuel becomes solid.

Whilst the Pour Point of a distillate can be lowered using additives, the Cloud Point is not affected by such additives. This means that even when a distillate has a very low Pour Point, it’s Cloud Point could be very much higher. As the fuel temperature drops to, or below the Cloud Point, wax crystals will start to form, at which point, filter clogging could begin to take place, resulting in fuel starvation and engine stoppage. Satisfactory storage, transfer and filtration needs a fuel temperature about 3-5°C above the Cloud Point. The Cloud Point of fuels used for emergency equipment should be below the ambient temperatures at which the equipment it is operating, or likely to operate.

One real case example saw a fuel in a lifeboat engine storage tank which had a Pour Point of -33°C whilst the Cloud Point was +17°C. This fuel could only be safely used at ambient temperatures above 20°C.

The additives used can also potentially cause operational problems as some of their chemicals can be absorbed by filter materials, causing them to appear blocked. This problem is exacerbated for emergency equipment which are typically fitted with very fine filters.

Fatty Acid Methyl Esters (FAME)
Due to the practice of blending FAME into automotive diesel and heating oil, it is now more common and indeed inevitable, that some distillates supplied in the marine market contain FAME. FAME can lead to complications with respect to storage and handling in a marine environment, due to its increased level of oxidation tendency, long-term storage issues or shorter shelf life, it’s affinity to water and risk of microbial growth. Additional issues regarding FAME’s degraded low-temperature flow properties and FAME material deposition on exposed surfaces, including filter elements, also add to the fuel management concerns. Therefore, testing for the presence and levels of FAME within marine distillates, is a highly recommended practice.

Visual Appearance
Fuels grades DMA/DMZ/DMX should be bright and clear. If the fuel is hazy, it could indicate the presence of water or a high Cloud Point. Haziness could also indicate poor oxidation stability.

Sulphur Content
Vessels (including emergency equipment) required for securing the safety of a ship, or saving life at sea are exempted from the MARPOL Annex VI Regulation 3.1.1 Sulphur requirement. However, for the testing of emergency equipment in an Emissions Control Area (ECA), compliant fuel with sulphur content less than 0.10 % m/m should be used.

Fuel contamination, a potential hazard
Since fuels in the emergency equipment storage tanks remain unused for long periods of time, quality of such fuels may deteriorate due to the following:
Water can originate from contaminated fuel or condensation, and engines may not run because of water in the fuel lines. The presence of water can promote growth of microorganisms such as bacteria, yeast and fungi, and can also lead to blockage of fuel lines and filters due to icing when ambient temperature drops below 0°C.

Microorganisms (bacteria, yeast, fungi) – Given the correct conditions in fuel storage systems, micro-organisms can grow and multiply. Bacteria, fungi and yeast are living organisms which may be present in fuel storage tanks and in particular where water is allowed to build up. Distillate fuels are more prone to bacterial infection. Microbial infection can lead to slimy deposits in tank bottoms, plugging of filters, pitting corrosion on fuel tank bottoms or at oil water interface and injector fouling.

Gas Oil Stability – Many different chemical reactions can cause a gas oil to be unstable. Instability can lead to sedimentation and eventually to the formation of gums. Instability is usually indicated by a colour change over a period of time.

Mitigate your emergency equipment risks
It is thus obvious from the above reasons that engines, which should be the most reliable of all, may fail to operate when they are most needed.

Testing of the fuel’s cold-flow parameters, FAME content, sulphur levels, water content and microbiological activity, is highly recommended. These tests will provide vital information and knowledge of a fuel’s quality and the management requirements that go beyond adherence to imperfect specifications. These are necessary to help ship operators deal with fuels which may meet the specification numbers but give serious operational problems. 

To find out more about the VPS testing packages for Emergency Equipment, please contact: marketing@vpsveritas.com

World Leading Maritime Decarbonisation Advisory Services company VPS, is pleased to announce the appointment of John MacKenzie, as the company’s new Group Strategic Business Development Manager. In this role, John will lead the global initiatives aimed at advancing VPS's partnerships with new and existing strategic clients. His efforts will play an integral role in the continued leadership of VPS within the testing and advisory space, acting as a focal point for clients.

At the start of his career John led business development efforts for a leading on-shore testing and certification business, quickly transitioning into the International Marine space. His specialism transcends client management, Oil Condition Monitoring (OCM) and fuel testing. He continued to strengthen his knowledge of the maritime sector, serving time with ExxonMobil Marine Lubricants and latterly as Sales Director within a global ship management and services company. With over a decade of experience managing key maritime accounts and leading business development teams, John has developed a deep understanding of how to deliver tangible value to clients and operate as a true partner, in tackling the everchanging demands of the marine industry.

Dr. Malcolm Cooper, VPS CEO, stated: “The maritime industry is changing fast with ambitious emissions targets and decarbonisation requirements driving the introduction of new technologies and fuels into the market. In this dynamic landscape, we are very pleased to have John on board to help VPS customers optimise their operations by understanding which new fuels to use and how to adapt to these sustainable business drivers and meet new regulations.”

“Whilst the industry is rightfully focussed on the path towards Net Zero, we must ensure we do not take our eye off the ball on the operational risks posed by traditional fuels.” Said John MacKenzie. “That said, it’s an evolving landscape, with a variety of legislations and an even wider array of future fuels. VPS leads the way in testing fuels like Methanol and marine Biofuel, making them a strategic partner for clients in their efforts to Net Zero.  

I’m incredibly excited to be involved at the sharp end of the industry’s fuel transition. Knowledge and experience are at a premium and VPS holds both, nicely packaged into our advanced Digital Decarbonization platforms: PortStats and Maress. The team is filled with experience and determination and I look forward to adding mine into the mix.” 

ABOUT THE SEMINAR
In keeping with our ongoing commitment to provide our partners with the highest level of support to meet & overcome the significant challenges posed by the decarbonization for shipping that includes the use of new fuels such as Biofuels as well as smart fuel management & energy efficiency measures, we are pleased to host this seminar inclusive of a panel discussion by industry experts.

The topic will cover our experience with existing fuels, the role of Biofuels and its increased usage, as well as energy efficiency measures that needs to make an impact today. With an expert panel who have significant knowledge of shipping rules, application & pragmatic management, this seminar aspires to leave participants with actions they can take now to make a difference in the challenging decarbonization journey.

DATE & TIME:
Thursday, 28th March 2024
09.00 – 12.00

PROGRAMME:
09.00: Registration and Coffee
09.30: Welcome and Opening Speech
• Mr Wu Zhong Qing, Director, Shipping Development and Promotion Center ofPudong New Area Shanghai
• Mr Zhang Wei, Director, MSA Shanghai
09.40: Session 1: Fuel Quality & New Fuels Challenges
by Capt. Rahul Choudhuri, President Strategic Partnerships, VPS
10.10: Session 2: Shipping Decarbonization Challenges
by Mr James Huang, Senior Vice President, DNV
10.40: Teabreak
11.00: Panel Discussion with Industry Experts
• CHIMBUSCO, Mr Tian Ming, General Manager, Enterprise Mgmt & Development Div.
• DNV, Mr Li Ling, Head of Technical Support, DNV Maritime Greater China
• GARD, Mr Yang Yang, Senior Lawyer, Defence/Charterers & Traders Claims Asia
• GREEN MARINE GROUP, Mr Donnie Bagang, Managing Director
• THE METHANOL INSTITUTE, Mr Zhao Kai, Chief Representative China
• SDARI, Mr Li Xin, Director, Innovation Center
• VPS, Capt. Rahul Choudhuri as Moderator
12.00: End of seminar followed by lunch

LOCATION:
30th Flr, Jin Mao Tower, Shanghai, China
Seminar Support unit: Pudong New Area Government

To register for the seminar, please click here.

Registration is on first come, first served, and closes on 22-March.

Article by Dr. Sunil Kumar

Environmentally friendly fuels like biodiesel blended with petroleum distillates can have an impact on the cold flow property. Currently biodiesel is one of the choices which is renewable, biodegradable, and less toxic compared to fossil fuels. Biodiesel significantly reduces carbon dioxide, carbon monoxide, sulfur oxides, volatile organic compounds, particulate matter, and unburned hydrocarbons when compared to petroleum distillates like Marine Gas oils (MGO), very low sulfur fuel oil (VLSFO) and Heavy fuel oil (HFO).

Cold flow prediction of biodiesel blended petroleum distillates is very important when a ship is sailing through cold weather regions. The cold flow characteristics of a blended fuel can be different from the individual fuels used for blending. MGO, VLSFO and HFO basically originate from fossil fuels whereas biodiesel is from a renewable source. Both are essentially hydrocarbons but contains compounds with different structural characteristics and properties. So, the structural difference of the compounds responsible for the cold flow property shall be considered since it is a physical phenomenon. This will have an impact on the cold flow property of the fuel since the blend is from two different origins and can sometimes lead to unpredictable paraffin agglomeration.

Veritas Petroleum Services (VPS) has various test methods in place to evaluate the cold flow property of the biodiesel blended fuels. The Laboratory determined test results can help the ship operators to make the right decision how to handle the fuel at low temperatures.

Cold Flow Property of Biodiesel, MGO, VLSFO and HFO
Biodiesel, MGO, VLSFO, and HFO share a common characteristic: the presence of polymethylene groups influencing cold flow properties. The severity of low-temperature flow centers on the amount of heavier paraffins present, with longer polymethylene chains exacerbating the impact. Biodiesel, while advantageous in many respects, falls short in cold flow performance, prone to wax crystallization in colder climates, leading to potential filter blockage and potential engine damage. The composition of these fuels, particularly the presence of saturated and unsaturated paraffins, significantly affects their cold flow properties. Different feedstocks for biodiesel production yield varying performance in low temperatures; for instance, palm oil-based biodiesel fares worse than soybean-based biodiesel due to differing paraffin characteristics. Origin, whether plant or animal-based, profoundly influences cold flow properties, necessitating meticulous evaluation, especially in blends with MGO, VLSFO, and HFO. Proper assessment of low-temperature behavior is critical for blended fuels with diverse sources and characteristics.

VPS Laboratory Scale Evaluation
There are several test methods used to determine the cold flow characteristics in fuels like MGO, VLSFO, HFO, biodiesel, and their blends. VPS utilises four main methods: Cloud Point (CP), Pour Point (PP), Cold Filter Plugging Point (CFPP), Wax Appearance Temperature (WAT), and Wax Disappearance Temperature (WDT). CP indicates the onset of paraffin crystallization, serving as an estimate for operational limits. PP signifies near-complete paraffin crystallization and guides the lowest usable temperature. CFPP indicates filter clogging due to paraffin crystallization, impeding fuel flow.

Each test offers insight into how a fuel behaves in cold conditions. However, methods ISO3015 (visual method) and ASTM D5773 (optical light source) can only be used to measure cloud point when the “petroleum products are transparent in layers 40mm in thickness”. For this reason, VPS researched and developed an “Automatic Test Method for Wax Appearance Temperature of VLSFOs” and published a White Paper on this in 2019.  

VPS Innovative (WAT/WDT) method for Non-Transparent Fuels
The ASTM D5773 method is used to determine the cloud point of clear petroleum products and biodiesels. VPS's innovation extends this to dark fuels like VLSFO, HFO, and biodiesel blends.

The VPS developed method WAT/WDT test offers a comprehensive view of wax appearance and crystallization temperatures in blended biodiesel with MGO, VLSFO, and HFO. This provides an extensive insight into low-temperature behavior, complementing conventional tests. There's a correlation between cloud point and WAT, both marking the onset of wax appearance.

Appendix 1 and 2 details some test results of various fuel types identifying the variance in the cold flow properties that are identified by tests in addition to the conventional ISO 8217 tests.

VPS Innovative Gas Chromatography (GC) method for the Biodiesel Impurities in the Fuel Blend
Impurities in biodiesel with FAME, arising from incomplete transesterification of feedstocks, can impact cold flow properties. Elevated total glycerol due to incomplete conversion and glycerol residue can cause issues like injector deposits and clogged systems. These impurities can affect cold weather performance when blended into fuels. Compounds like saturated monoglycerides (SMG) can precipitate above the blend's cloud point, potentially causing filter plugging. EN 14105 assesses free glycerol and residual glycerides in B100. VPS's innovative GC method determines mono-, di-, triglycerides, and free glycerol in biodiesel blends with MGO.

Conclusion
The diverse paraffin compositions in biodiesel blends pose challenges in establishing a general cold flow property relationship. These paraffins, from both biofuel and fossil fuel origins, add complexity to the crystallization process. The structural differences between biodiesel and diesel fuel compounds leads to an inconsistent flow behaviour of the blended fuel.

Given the unpredictable nature of low-temperature flow characteristics in blended biodiesel, comprehensive laboratory tests are crucial. Conducting CP, PP, CFPP, WAT/WDT, and GC analysis aids in understanding SMG in MGO blended biodiesel is recommended. Such thorough testing provides valuable insights into the cold flow properties of biodiesel blends.

For further information on how VPS can support you in your fuel management of marine biofuels, please contact: marketing@vpsveritas.com

Appendix 1

Cold Flow Property of Biodiesel Blend
Laboratory scale study has been carried out in order to evaluate the cold flow property of biodiesel blended fuels.

Following four fuels were selected for the Biodiesel blend study.

1.    MGO
2.    Low pour point VLSFO
3.    High pour point VLSFO
4.    HFO

Prior to blending the fuels in various ratios, the cold flow property of the selected fuels (Biodiesel, MGO, Low and High pour point VLSFO’s and HFO) were determined and the results are given in Table 1.

Table 1 - Cold flow Properties

X: Not applicable

A general limited evaluation of the type of paraffins present in the MGO, Low and High pour point VLSFO’s, HFO and the FAME in the biodiesel which are responsible for the cold flow property was carried out by GCMS analysis on the 325⁰C vacuum distillate cut, and its carbon number represents the chain length of the polymethylene groups responsible for the cold flow property is given in Table 2.

Table 2 - Carbon Chain length of the Polymethylene Segments Responsible for CFP

CN-Carbon Number; SP-Saturated Paraffins; IP-Iso Paraffins; SF-Saturated FAME; UF-Unsaturated FAME; PUF-Poly Unsaturated FAME; BSF-Branched Saturated FAME; X-Not Present

The four fuel types MGO, high and low pour point VLSFO’s, HFO was selected ande blended in different proportions with Biodiesel for cold flow property evaluation.

Table 3 - Blend proportion of MGO, VLSFO and HFO with Biodiesel

BD-Biodiesel

Table 4 - Cold Flow Property Results of Blended Fuels

Appendix 2

Biodiesel Blend with MGO
The low CP, CFPP, Pour point of the MGO indicates the presence of less concentrated long chain saturated paraffins. MGO blended with biodiesel in different proportions show an increase in the CP, CFPP, Pour point and WAT (Fig 1). The CFPP result of the 30% biodiesel blend resulted the filter clogging and this could be due to the crystallizable paraffin’s contributed from the biodiesel.

Fig 1 - Biodiesel Blend with MGO

Biodiesel Blend with Low Pour Point VLSFO
The Low Pour Point VLSFO received has already contained fatty acid methyl ester compounds having saturated, unsaturated, and polyunsaturated polymethylene groups along with the saturated paraffins and iso-paraffins from the VLSFO. The VLSFO blended with biodiesel in different proportions shows a decrease in the WAT and a considerable drop has been observed at 10% VLSFO blend (Fig 2). It was observed that there is an increase in the pour point, but the increase was stabilized from 10% to 70% biodiesel blend and then a sharp increase at 90% blend. This shows the inconsistent wax crystallization behaviour of the blended fuel.

Fig 2 - Biodiesel Blend with Low Pour Point VLSFO 

Biodiesel Blend with High Pour Point VLSFO
High Pour Point VLSFO blended with biodiesel in different proportions shows a decrease in the pour point and WAT, but a considerable drop hasn’t been observed from 10% to 70% blend (Fig 3).

Fig 3 - Biodiesel Blend with High Pour Point VLSFO

Biodiesel Blended with HFO
HFO blended with biodiesel in different proportions show decrease in the pour point and WAT, but a considerable drop has been observed above the 70% blend (Fig 4).

Fig 4 Biodiesel Blend with HFO

Article by Harun Rashid, VPS Senior Technical Manager.

Stability has long been a highly unpredictable character of marine fuels, which is extremely sensitive to a fuel’s formulation and its storage and handling conditions. For these reasons, fuel buyers have no direct control on fuel stability, unlike other physical parameters, other than relying upon a supplier’s due diligence regarding the fuel formulation and the ship’s engineer’s professionalism in managing the fuel on board.

Asphaltenes within residual-based fuels can precipitate as sediment/sludge whenever a fuel’s available solvency to retain asphaltenes in suspension drops below the fuel’s stability reserve. The ISO 8217:2012/17 standard has a sediment limit of a maximum 0.10% m/m to protect buyers’ interest where an elevated sediment value can be indicative of an unstable fuel. Today’s fuels are no longer produced from straight run refining processes, but undergo a series of complex processes, for example, vacuum distillation, vis-breaking, catalytic cracking, in order to extract the lighter end components as much as possible, leaving the bottom end components with reduced reserve stability. The solvency can further diminish with unregulated blending in order to meet the Sulphur compliance levels within MARPOL Annex VI & statutory regulations.

During 2023, VPS handled numerous sludge formation cases which led to severe filter & separator blockages. The majority of these cases involved VLSFO fuels and for a sizable number, the sediment content at the ship’s manifold was actually below the 0.10%m/m specification limit. In one case, a ship received a VLSFO in an Asian port with sediment content 0.07%m/m and reported severe sludge formation soon after the fuel was put into use, with sludge formation continuing throughout the use of the fuel.

The sludge formation was so severe that the engineers had to clean the purifier bowl assembly every 4 hours, compared to a usual cleaning interval of 250 hours. At one point, the engineers discontinued using the fuel, as the vessel ran out of spare parts. Analysis of system samples later confirmed that the sludge formation was indeed due to unstable fuel and not from on-board mixing.

While the number of sludge formation cases clearly singles out VLSFO as more unstable and challenging to manage on-board, compared to HSFOs, another challenge is to prevent wax formation without exposing fuel to excessive heat and accelerated fuel ageing. With VLSFOs being  more parafinnic in nature, a good number may require heating beyond their pour point to prevent wax formation.

VPS 2023 data shows, at least 15.8% of VLSFO samples had a wax apperance temp (WAT) above 40C, including 1.6% above 50C. These samples will precipitate wax if storage temps are not kept above the WAT, compared to the lower storage temperature requirements based on their tested pour points. Wax formation is a reversible process, so theoritically, it should not cause any operational issue as long as fuel remains stable, but unfortunately, fuel stability is not guanteed. Moreover, if wax is allowed to form, wax and aspheltenes (sludge) can co-mingle together as a result, the wax disappearnce temperature may increase significantly and in the worst case, the wax may no longer disappear. Taking a middle approach and strking a balance could be one option where the fuel is not severly overheated, nor the wax allowed to form freely during storage and only increase temperatures during transfer if needed. VLSFO with such high WAT/WDT will need close attention and care during storage, transfer, treatment and use. Prolonged storage should also be avoided for such fuels.  

Sludge formation on the other hand is an irreversible process, meaning it is not possible to convert the precipitated sludge back into the fuel. As there is no quick fix, efficient handling of fuel treatment plants becomes so critical otherwise, severe clogging of filters and separators can lead to fuel starvation to the engine and a loss of propulsion placing greater risk to the safety of the crew, ship, and the environment.

Avoiding a catastrophic situation requires visiting the entire fuel management chain and adhering to best practices. It starts with buying fuel from trusted suppliers, followed by verifying the fuel quality in one of the VPS, ISO17025 accredited laboratories.

VPS offers  an Additional Protection Service (APS) package which includes a stability assessment of the fuel.

VPS additional protection service (APS) package

Parameters such as Separability Number (Reserve Stability Number) and Total Sediment Existent (TSE) together with Total Sediment Potential (TSP) results provides an excellent indication of fuel stability while GC/MS screening and follow up testing ensures the fuel is not contaminated with harmful chemical species at levels considered “unfit for use”. Testing Wax appearance & disappearance temperatures assist in maintaining optimal heating to prevent wax formation whilst also avoiding overheating and fuel ageing.

If a vessel uses stability additives, then its performance evaluation should not only be in assessing the improvement of the reserve stability number, but to conduct a broader assessment across fleet including assessing sediment reduction. Crew training is key, as poor handling of fuel by incompetent crew can also trigger a sludge formation situation.

A deeper understanding of the fuel’s quality can be achieved, coupled with a further reduction of any associated risk, by going beyond ISO 8217 and using the APS test scope. This service will ultimately save time, money and company reputation.

For further information and support in the fuel management of VLSFOs please contact: marketing@vpsveritas.com

Article by Steve Bee, VPS Group Commercial Director, Dr Malcolm Cooper, VPS CEO, Stanley George, VPS Group Science & Technical Manager.

Bad bunkers can significantly impact vessel operations, necessitating intervention from the crew and in some cases result in operational failure - varying from operational damage through to loss of power and subsequently loss of propulsion. Mitigating the impact of bad bunkers can help to prevent damage to vessel’s equipment and protect the safety of those on board and the environment. Bad bunkers can lead to fuel stability problems, chemical contamination and poor cold-flow properties. This paper describes the key steps that should be taken to avoid the risk of receiving bad bunkers.

Bad Bunkers
Bad bunkers refer to fuel of substandard quality, which can lead to operational disruptions and challenges in fuel management. Common fuel quality concerns include poor stability, chemical contamination, corrosive tendencies, poor combustion and poor cold flow characteristics. Thorough testing of bunkered fuel prior to putting it in operation is highly advantageous as it reveals potential issues inherent in the fuel. This data often enables proactive measures to mitigate the risk of operational complications stemming from such fuel.

Whilst the general quality of bunker fuel has been consistent over recent years, it is important to note that off-specification fuel statistics are typically based on the criteria outlined in Table 1 and 2 of ISO 8217 standard. There have been numerous occasions when bunker fuel meeting these criteria has proven to be unsuitable for onboard use due to its poor quality and on a number of occasions has caused catastrophic failures (e.g. ARA contamination case - August 2022 and March 2024, Houston contamination case April 2023 and Singapore contamination case August 2022). This necessitates additional testing methodologies such as GCMS, WAT/WDT, and Reserve Stability Number to accurately assess fuel quality.

The increase in reported operational issues stemming from contaminated fuels, which often elude detection through routine ISO 8217 testing, has experienced a notable uptick in recent years. This trend can be attributed, at least in part, to the drive towards decarbonization, notably spurred by initiatives such as IMO 2020. Consequently, fuel suppliers are increasingly experimenting with a diverse range of feedstocks to serve as blend components in conventional fossil fuels.

As the world’s largest marine fuel quality testing company covering 50% of all fuel testing, VPS can offer valuable insights and advice in relation to poor quality and/or contaminated fuel. Proactive, pre-burn, fuel testing on a regular basis, is definitely a highly recommended approach to mitigating risks to vessel operations, crew safety and environmental impact. The typical off-specification parameters associated with engine failure are usually Pour Point, Total Sediment Potential, Cat-fines and/or Water content. Whilst the International Marine Fuel Quality standard, ISO8217, includes these test parameters, it’s certainly a more diligent and wiser approach, to consider a fuel’s overall stability, cold-flow properties, chemical contamination and potential corrosivity.

At VPS, we possess the proficiency and extensive experience necessary to conduct specialised tests specifically designed to detect these issues. Our tailored testing protocols enable us to identify potential fuel-related challenges and offer operational guidance to minimise associated risks effectively.

Fuel Stability
Both High Sulphur Fuel Oils (HSFOs) and Very Low Sulphur Fuel Oils (VLSFOs), can suffer with varying degrees of instability due to thermal-aging and over-heating, high sediment content, or chemical contamination, to name but a few potential causes. Instability usually manifests itself through sediment formation, which can in turn, block onboard filters, pipework, potentially then starving an engine of fuel.

ISO8217 includes the Total Sediment Potential (TSP) test, which is a good indicator of the amount of sediment which may be potentially produced in relation to a fuel’s stability. However, additional tests such as Total Sediment Accelerated (TSA), a deliberate fuel-aging test, Total Sediment Existent (TSE), a measure of fuel cleanliness and the determination of a fuel’s stability reserve, via Separability Testing, to measure the fuel’s capacity to hold long chain asphaltenes within the fuel solution, can provide much more information regarding fuel stability determinations.

In particular, Separability Number is an excellent accompaniment to the routine hot filtration methods. It can identify potentially troublesome unstable fuels even when the Hot Filtration Test methods indicate a low sediment content.   Conversely, it may indicate that a high sediment fuel is in fact quite stable and unlikely to form sludge. This information in combination, is extremely useful from an operational perspective, as it will indicate in advance if and what mitigation steps are appropriate.

Chemical Contamination
Over the years chemical contamination of marine fuels has resulted in many onboard operational issues, with numerous chemicals and chemical groups being identified as the cause. Major widespread contamination events, include Houston (2018), with over 200 vessels damaged due to a potential phenolic contamination, to Singapore (2022) where 80 vessels were affected by chlorinated hydrocarbons within the fuel and then more recently ARA (2023) where around 20 vessels suffered issues due to a cocktail of styrenes and dienes within the fuel. In between such times, many smaller cases of chemical contamination have been identified by VPS. Thankfully, many at a pre-burn stage, thus avoiding any operational issues or damage cases.

Over time, all of the following chemicals have been found by VPS in marine fuels. The effects of these are highlighted below:

Risks from chemical contamination of fuel can be significantly mitigated through pre-burn screening of fuels using VPS Chemical Screening Service. This low-cost test, utilising Gas Chromatography Mass Spectrometry (GCMS) analysis, will warn of the presence of over 70% of all volatile chemicals within fuel. With both VLSFO and HSFO we continued to see cases of vessel damages due to chemical contamination during 2023. Focusing specifically on the VPS GCMS-Head Space Chemical Screening service, as a damage prevention service, 19.9% of applicable marine fuel samples received by VPS since 2018, have undertaken this rapid, pre-burn protection service, with an average 8% of samples tested, giving rise to a “Caution” result, indicating the presence of at least one chemical contaminant and thus the notified vessel has avoided any damages.

In April 2023, a Singaporean-owned chemical and product tanker bunkered 415 m/tons of VLSFO in Houston. The vessel began to burn the fuel in May and quickly began to experience numerous issues with the auxiliary and main engines, such as exhaust gas deviating temperatures and the wearing of fuel pumps and plunger barrels. In addition, problems such as start-failure due to insufficient fuel injection, pressure build up, as well as worn out and leaking fuel pumps.
Of greater concern was the complete engine stoppage enroute to the next US port, when the main engine failed. Multiple attempts were made to start the engine, all without success.

Subsequent VPS forensic laboratory testing, utilising a proprietary Gas Chromatography Mass Spectrometry (GCMS) Acid Extraction methodology, detected the presence of several phenols and fatty acid compounds within the fuel.

The vessel initiated the necessary repairs to both auxiliary and main engine fuel pumps, at a total spares cost of $200,000. In hindsight the vessel owner stated pre-burn screening would have helped significantly in avoiding such damages and costs.

Cold-Flow Properties

The cold-flow properties of fuels are also important to monitor closely, especially when sailing in colder temperature regions. The Pour Point of HSFOs, VLSFOs and MGO fuels, should always be monitored when colder climates are encountered. Pour Point was the most common MGO off-specification parameter in 2023, with 36.6% of MGO off-specs attributed to Pour Point. However, prior to reaching the pout point of MGO fuel, its cloud point and cold-filter plugging point behaviour offer earlier warning-signs of potential cold-flow issues, relating to wax precipitation from the fuel. It is key fuel management practice to measure these two cold-flow parameters within MGO distillates.

VLSFO fuels have a higher paraffinic content than HSFO and as a consequence, have a greater potential to precipitate wax, which can cause filter and pipework blockages, which can ultimately starve an engine of fuel. As VLSFOs are dark fuels, the cloud point cannot be seen, as it can with a distillate fuel. Therefore in 2019, VPS developed a proprietary test method to measure the Wax Appearance (WAT) and Wax Disappearance Temperatures (WDT) of VLSFOs.

Generally, it is recommended that the fuel temperature is kept approximately 10oC above the PP to avoid risk of solidification. However, in the majority of the global bunker ports in 2022-23 the average WAT was often higher than 30oC, and WDT higher than 40oC. This may also mean heating the fuel to avoid solidification during transfer. However, this should not necessarily mean an increase in storage temperature. Fuel oil transfer pumps on board are generally positive displacement pumps and can handle certain amount of wax that are present in the fuel.

If the fuel has a high WAT/WDT, VPS recommend heating the fuel just before the transfer operation.

Therefore, additional fuel tests, such as, Total Sediment Existent (TSE), Separability Number (Reserve Stability Number, RSN), Wax Appearance/Wax Disappearance Temperature Testing, Cloud Point, Cold Filter Plugging Point and Chemical Screening, can provide significantly greater and more valuable protective information, when assessing fuel quality than ISO8217 alone. This is why VPS offer our Additional Protection Service (APS) “bundles”. The APS includes the standard ISO8217 parameters but also fuel-relevant additional tests, in order to support our customers to greater levels with respect to, asset, crew and environmental protection.

Over the years, VPS Off-specification fuel data has proactively highlighted the potential risks associated with certain parameters. The importance of regular and wider-ranging marine fuel testing, through the Additional Protection Service, will definitely support mitigation strategies to prevent disruptions in vessel power supply due to fuel-related issues. Even a minor fuel quality issue can prove costly. A 2018 report by the Swedish Club highlighted the average cost per incident of fuel-related damage on vessels is $344K.

For further information on how VPS Additional Protection service can improve your fuel management and avoid potentially catastrophic failures, please contact your local VPS Account Manager or marketing@vpsveritas.com

As global market leader in marine fuel testing and bunker quantity surveys, VPS has tested the most marine fuel samples in the market to-date and has witnessed first-hand what new fuels have to offer, and what the expected issues and risks in managing these fuels will be. Based on this data, VPS has launched Marine Fuel Insights.

Marine Fuel Insights is a quarterly subscription-based service, where VPS’ technical expertise is combined with its proprietary database of fuel oil and distillate samples, to derive special insights for its users. Subscribers receive insights on: availability of VLSFO, quality of tested fuels, potential operational issues, fuel performance, operational characteristics, compliance levels.

Stay ahead in the marine fuel industry with Marine Fuel Insights.

Barendrecht, Netherlands - To meet evolving market requirements VPS launches Emsys ShoreLink to provide MRV/EU ETS-ready off-ship data capability. Vessel owners will now have the ability to get direct, real-time emissions readings sent to shore. This allows vessel owners to do unprecedented operations optimization to minimize emissions footprint - in a market where owners are required to manage not only CO2, but also even more potent climate gases such as Methane.  

The existing VPS Emsys solution offers an accurate emissions measurement, designed to help the maritime industry precisely measure and manage emissions from vessel smokestacks. With the added value of Emsys ShoreLink, the data can be sent directly to other systems for further analytics and direct EU ETS reporting.  

Benefits of off-ship-data in the face of tightening regulations 
Shipowners and operators are required to monitor and report their CO2 emissions. Traditional methods relying on standard emission factors often result in inaccuracies, leading to wrong decision-making and potential environmental and financial damage. Emsys stands as a market leader in providing the class-approved technology capable of providing full-range methane slip measurements up to 20,000ppm, a critical component for compliance with stringent EU regulations. Analysis of emission performance in relation to operational pattern and engine load enables taking the right decisions to reduce GHG emissions and methane slip. In terms of MRV reporting, which is fundamental for the ETS, the latest EU regulation amendment introduces the option direct measurement of greenhouse gas emissions.  

VPS Emsys now offers both standalone systems and holistic solutions, ensuring end-to-end management of methane slip and greenhouse gases (GHG) with unmatched accuracy and reliability. A unique and proven technology for minimum maintenance and maximum reliability. The real-time monitoring and data analysis capabilities enable shipowners to make informed decisions to reduce GHG emissions and methane slip effectively, and the system is used on more than 200 vessels today. 

How does Emsys ShoreLink work? 
Emsys is a hardware-based emission measurement system providing on-ship data in PDF or CSV format, suitable for printing or emailing. Emsys ShoreLink facilitates a live data export, enabling off-ship data transfer through most commonly used IAS and IOT systems. Bringing Emsys data to shore opens new opportunities for real-time monitoring of emissions performance for the fleet.  

Simon Brown, VP Emissions Measurement VPS stated: “Emsys ShoreLink represents a significant advancement in emissions measurement technology, offering shipowners and operators the tools they need for precise and reliable emissions management. By integrating real-time data transfer and analysis capabilities, we empower our clients to make informed decisions that enhance both environmental compliance and operational efficiency."

If you are an owner of an Emsys system, reach out to VPS to explore how our innovative ShoreLink capability can benefit your operations. By using Emsys ShoreLink, you can enhance your fleet's emissions management, ensuring compliance with regulatory standards and optimizing performance. 

For more information and to explore how VPS Emsys can enhance your fleet’s emissions management, contact us at decarbonisation@vpsveritas.com