Analysis

Peninsula Petroleum: Low viscosity vs. lubricity

‘Lubricity is not a major concern for marine fuels and is only applicable to ultra-low sulphur “bright & clear” distillate fuels,’ says Jeroen de Vos.

Published

3 years ago

May 30, 2022

Admin

Jeroen de Vos Peninsulas Head of Quality

The following article was published by Jeroen de Vos, Head of Quality at Peninsula Petroleum, through the social media platform LinkedIn on Friday (27 May):

Viscosity is defined as the resistance of a fuel to flow and is a measure of the fluidity of the product at a certain temperature. The viscosity of a fuel decreases when the fuel temperature increases i.e. it becomes more fluid. The significance of viscosity for marine fuels is such that;

- It is used as an indicator of the grade
- It defines the heating temperatures for storage, transfer, fuel treatment and injection
- It is used for the calculation of CCAI (the index of the ignition quality of residual fuel oil)

Viscosity is not an indication of fuel quality, and it is a misunderstanding that residual fuels with a lower viscosity automatically means that the product is lower in quality. In reality, viscosity only becomes a serious quality concern when the viscosity is below 2 cSt. Historically, viscosity was used to order a fuel by indicating the grade based on the viscosity of the product. Viscosity was also a key blending target for refineries and fuel suppliers where blending was usually done using a low-quality, heavy residual stream (e.g cycling oils containing considerable amounts of highly abrasive cat fines).

With the introduction of the global Sulphur cap of 0.50%, density and viscosity were no longer the main blending targets, but instead it was replaced by sulphur as the main blending target. To produce 0.50% fuels, it is no longer possible to use large quantities of low quality and heavy residual streams in the blend. Instead, lighter blending components are being used such as higher quality refinery streams and even distillate fuels. These different blending components have inherently lower viscosity and density properties resulting in a lower density and viscosity product but with a higher overall quality. Therefore, low viscosity and low density fuel products are generally an indication of a better quality product.

Lower viscosity fuels are in general;

- Higher in energy content
- Lower in cat fines and other metals
- Lower in CCAI
- Requiring lower fuel temperatures so less thermal stress
- Easier to perform onboard fuel treatment (Stokes law)

Peninsula Petroleum: Low viscosity vs. lubricity

Lubricity is the measure of the reduction of friction of a product. The misconception is that lower viscosity fuels might be more susceptible to lubricity issues. It is known that lubricity is not a critical parameter and only applicable to ultra-low sulphur distillate fuels e.g. ISO 8217 includes lubricity for clear and bright distillate fuels only when sulphur is below 0.05 % m/m.

Lubricity was introduced as an ISO 8217 specification parameter with the release of the 2010 edition. The lubricity criterion was adopted from the automotive industry, where a variety of fuel pumps and fuel injection systems were damaged by low sulphur fuels with poor lubricity. The main reason behind poor lubricity is that the removal of sulphur during the refinery process also impacts (reduce) the lubricity capacity of a fuel.

For marine, the impact is significantly less as marine fuels still contain sulphur and thereby normally maintains its lubricity capacity. For the marine industry, some engine manufacturers recommend testing for lubricity to be carried out only if sulphur is below 0.01% m/m.

What is often overlooked but what is recognized to be more critical for marine fuel system and diesel engine fuel pumps is when the viscosity will be less than 2 cSt. Reason is that with a too low viscosity a satisfactory hydrodynamic oil film between fuel pump plunger and barrel cannot be maintained, thereby causing the risk of fuel pump seizures and/or sticking. So a very low-viscosity fuel oil challenges the function of the pump in three ways:

Breakdown of hydrodynamic oil film (resulting in seizures),
Insufficient injection pressure (resulting in difficulties during start and low-load operation), and
Insufficient fuel index margin (resulting in limitation in acceleration and load).

Peninsula Petroleum: Low viscosity vs. lubricity

To mitigate the risk of low viscosity a cooler or chiller might be needed to maintain the viscosity at the fuel pumps above the minimum of 2 cSt. This is due to increase in fuel temperatures during operation onboard a vessel a hot fuel system. What also should be noted is that fuel pumps with high running hours are more sensitive to the potential risks of using low viscosity fuels.

So in summary of the above we can conclude that:

A lower viscosity is not an indication of a lower quality product.
Fuel viscosity only becomes an issue when;

- The vessel is not able to maintain the required injection viscosity at engine inlet (lack of heating capacity)

- The vessel is not able to maintain the viscosity above 2 cSt at engine inlet (lack of cooling capacity)

3. Lubricity is not a major concern for marine fuels and is only applicable to ultra-low sulphur “bright & clear” distillate fuels

Photo and source: Peninsula Petroleum
Published: 30 May, 2022

Research

Yamna identifies five potential global ammonia bunkering hubs

Unlike methanol, ammonia is not constrained by biogenic CO2 availability, and its production process is relatively simple.

Published

3 weeks ago

December 31, 2024

Admin

Specialised green hydrogen and derivatives platform Yamna in early December identified several potential ammonia bunkering hubs around the world.

The hubs are Port of Rotterdam, Port of Algeciras, Suez Canal, Jurong Port, and Port of Salalah.

“The shipping industry faces an ambitious challenge: reducing emissions by 20% by 2030 (compared to 2008 levels) and achieving net-zero emissions by 2050, in alignment with IMO targets,” it stated.

“Achieving these goals in the medium to long term depends on the adoption of alternative low-emission fuels like green ammonia and methanol.

“Among these, ammonia is attracting growing interest as a viable option. Unlike methanol, it is not constrained by biogenic CO2 availability, and its production process is relatively simple.”

However, the firm noted kickstarting ammonia bunkering on a large scale required four enablers to align:

Ammonia fuel supply
Application technology
Bunkering infrastructure
Safety guidelines and standards

It believed ammonia bunkering hubs will first emerge where affordable and scalable ammonia supply is available.

Yanma Why use ammonia for bunkering fuel

Photo credit: Yanma
Published: 31 December 2024

Research

Port of Long Beach releases Clean Marine Fuels White Paper

Document intended to prepare and position the port and its stakeholder for adopting low carbon alternative fuels.

Published

3 weeks ago

December 26, 2024

Admin

Clean Marine Fuels Port of Long Beach (December 2024)

The Port of Long Beach (PLB) in late December released the Clean Marine Fuels White Paper as part of efforts to identify solutions capable of reducing emissions from ships.

“To understand the opportunities and challenges related to the adoption of clean marine fuels, the Port of Long Beach hired ICF Consulting to develop this white paper as an educational resource and guidance document,” stated PLB

“This document is also intended to prepare and position the port and its stakeholder for adopting low carbon alternative fuels.

“The white paper provides high level information on the array of currently available low carbon marine fuels, along with an exploration of the potential infrastructure needs for their deployment.”

The document covers the use of different types of clean bunker fuels such as green hydrogen, green methanol, green ammonia, renewable LNG and biofuels for shipping.

“The shift to clean marine fuels is no longer optional but a necessity for the sustainability of the maritime industry,” stated PLB in its closing remarks.

“This transition, while presenting challenges such as high costs, limited fuel availability, and the need for extensive infrastructure development, is advancing due to evolving policy frameworks and growing industry commitment.

“Addressing these obstacles will require targeted initiatives and robust collaboration between public and private sectors. Continued policy support, government funding, and sustained industry commitment will be essential to driving this progress and ensuring the long-term sustainability of maritime operations.”

Editor’s note: The 123-page Clean Marine Fuels White Paper may be downloaded from the hyperlink here.

Photo credit: Clean Marine Fuels White Paper
Published: 26 December 2024

Port & Regulatory

Clyde & Co: FuelEU Maritime Series – Part 6: Legal issues

Bunker purchasers should consider the wording of their bunker supply contracts carefully and ensure that they are comfortable with the contractual provisions.

Published

3 weeks ago

December 26, 2024

Admin

Global law firm Clyde & Co on Thursday (19 December) released the final instalment of its six-part series uncovering the FuelEU Maritime Regulation.

In it, the firm looked at the legal issues that could potentially arise between various parties, such as owners, charterers, ship managers, bunker suppliers, and ship builders, as a result of the compliance requirements imposed by the Regulation.

The following is an excerpt from the original article available here:

Bunker supply contracts - legal issues

Both vessel owners and bunker purchasers will want to ensure that they are able to take advantage of the preferential treatment provided under the FuelEU Regulation for consuming renewable fuels, including biofuels and renewable fuels of non-biological origin (RFNBOs) (such as methanol and ammonia).

Article 10 of the FuelEU Regulation states that such fuels must be certified in accordance with the Renewable Energy Directive (RED) 2018/2001. If the fuel consumed by the vessel does not meet the applicable standards or have the appropriate certification, then it “shall be considered to have the same emissions factors as the least favourable fossil fuel pathway for that type of fuel”[1].

In order to confirm that the fuel complies with greenhouse gas (GHG) intensity and sustainability requirements, the vessel owner and bunker purchaser will want to ensure that the bunker supplier provides the appropriate certification required under the FuelEU Regulation. The EU has required certification of such fuels, with the aim of guaranteeing “the environmental integrity of the renewable and low-carbon fuels that are expected to be deployed in the maritime sector.”[2]

The FuelEU Regulation provides that the GHG intensity of fuel is to be assessed on a “well-to-wake” basis, with emissions calculated for the entire lifespan of the fuel, from raw material extraction to storage, bunkering and then use on board the vessel.

Vessel owners and bunker purchasers will, therefore, need to be mindful of the importance of establishing how “green” the fuel actually is, and of the risk of bunker suppliers providing alternative fuels that will not allow for preferential treatment under the FuelEU Regulation.

It would, therefore, be advisable for bunker purchasers to consider whether the wording of their bunkering supply contracts is sufficient to ensure that the fuel is properly certified under the FuelEU Regulation. This could include contractual provisions that require the supplier (i) to provide a bunker delivery note (BDN), setting out the relevant information regarding the supply (such as the well-to-wake emission factor), and (ii) to provide the necessary certification under a scheme recognised by the EU.

Bunker purchasers should also be mindful that bunkering supply contracts often contain short claims notification time bars and provisions restricting claims for consequential loss. Issues could therefore arise where a purchaser tries to advance a claim against the supplier for consequential loss due to a lack of certification, but the bunker supplier argues that such losses are excluded under the terms of the bunker supply contract.

Bunker purchasers should therefore consider the wording of their bunker supply contracts carefully and ensure that they are comfortable with the contractual provisions.

Photo credit: CHUTTERSNAP from Unsplash
Published: 26 December 2024