Classes•Generally six fuel grades numerical specifications. •The boiling point and carbon chain length of the fuel increases with fuel oil number. •Viscosity also increases with number, and the heaviest oil has to be heated to get it to flow. •Price usually decreases as the fuel number increases.•Number 1 fuel oil is a volatile distillate oil - kerosene, gasoline•Number 2 fuel oil distillate - diesel fuel with a cetane number limit describing the ignition quality of the fuel. •Number 3 fuel oil distillate oil for burners requiring low-viscosity fuel. ASTM merged this grade into the number 2 specification, and the term has been rarely used•Number 4 fuel oil is a commercial heating oil for burner installations not equipped with preheaters.•Number 5 fuel oil is a residual-type industrial heating oil requiring preheating to 170 – 220 °F (77 – 104 °C) for proper atomization at the burners. This fuel is sometimes known as Bunker B. It may be obtained from the heavy gas oil cut, or it may be a blend of residual oil with enough number 2 oil to adjust viscosity until it can be pumped without preheating.•Number 6 fuel oil is a high-viscosity residual oil requiring preheating to 220 – 260 °F (104 – 127 °C). Residual means the material remaining after the more valuable cuts of crude oil have boiled off. The residue may contain various undesirable impurities including 2 percent water and one-half percent mineral soil. This fuel may be known as residual fuel oil (RFO)•Mazut is a residual fuel oil often derived from Russian petroleum sources and is either blended with lighter petroleum fractions or burned directly in specialized boilers and furnaces.

Table of fuel oils

Name Alias Alias Type Chain Length

No. 1 fuel oil No. 1 distillate No. 1 diesel fuel Distillate 9-16

No. 2 fuel oil No. 2 distillate No. 2 diesel fuel Distillate 10-20

No. 3 fuel oil No. 3 distillate No. 3 diesel fuel Distillate

No. 4 fuel oil No. 4 distillate No. 4 residual fuel oil

Distillate/Residual

12-70

No. 5 fuel oil No. 5 residual fuel oil

Heavy fuel oil Residual 12-70

No. 6 fuel oil No. 6 residual fuel oil

Heavy fuel oil Residual 20-70

• Small molecules like those in propane, naphtha, gasoline for cars, and jet fuel have relatively low boiling points, and they are removed at the start of the fractional distillation process.

• Heavier petroleum products like diesel and lubricating oil are much less volatile and distill out more slowly, while bunker oil is literally the bottom of the barrel;

• The only things more dense than bunker fuel are carbon black feedstock and bituminous residue which is used for paving roads (asphalt) and sealing roofs.

• Bunker fuel or bunker crude is technically any type of fuel oil used aboard ships. It gets its name from the containers on ships and in ports that it is stored in; in the early days of steam they were coal bunkers but now they are bunker fuel tanks.

• Bunker A is No. 2 fuel oil, Bunker B is No. 4 or No. 5 and bunker C is No. 6. • No. 5 or 6 are also commonly called heavy fuel oil (HFO) or furnace fuel oil (FFO);

the high viscosity requires heating, usually by a re-circulated low pressure steam system, before the oil can be pumped from a bunker tank. Bunkers are rarely labeled this way in modern maritime practice.

• International Organization for Standardization (ISO) has been the accepted standard for marine fuels (bunkers). The standard is listed under number 8217, with recent updates in 2005 and 2010.

• They have broken it down to Residual and Distillate fuels.

• The most common residual fuels in the shipping industry are RMG and RMK. The differences between the two are mainly the density and viscosity, with RMG generally being delivered at 380 centistokes or less, and RMK at 700 centistokes or less.

• Ships with more advanced engines can process heavier, more viscous, and thus cheaper, fuel.

• Governing bodies (i.e., California, European Union) around the world have established Emission Control Areas (ECA) which limit the maximum sulfur of fuels burned in their ports to limit pollution, reducing the percentage of sulfur and other particulates from 4.5% m/m to as little as .10% as of 2015 inside an ECA.

• As of 2013; 3.5% is continued to be permitted outside an ECA. • They have similar properties to Diesel #2 which is used as road Diesel around the

world. The most common grades used in shipping are DMA and DMB.• Greenhouse gas emissions resulting from the use of international bunker fuels are

currently included in national inventories

• MGO (Marine gas oil) - roughly equivalent to No. 2 fuel oil, made from distillate only

• MDO (Marine diesel oil) - A blend of heavy gasoil that may contain very small amounts of black refinery feed stocks, but has a low viscosity up to 12 cSt so it need not be heated for use in internal combustion engines

• IFO (Intermediate fuel oil) A blend of gasoil and heavy fuel oil, with less gasoil than marine diesel oil

• MFO (Marine fuel oil) - same as HDO (just another "naming")• HFO (Heavy fuel oil) - Pure or nearly pure residual oil, roughly equivalent

to No. 6 fuel oil

Standards and classification• CCAI and CII are two indexes which describe the ignition quality of residual fuel oil, and CCAI is

especially often calculated for marine fuels. Despite this, marine fuels are still quoted on the international bunker markets with their maximum viscosity (which is set by the ISO 8217 standard ) due to the fact that marine engines are designed to use different viscosities of fuel. The unit of viscosity used is the Centistokes and the fuels most frequently quoted are listed below in order of cost, the least expensive first-

• IFO 380 - Intermediate fuel oil with a maximum viscosity of 380 Centistokes (<3.5% sulphur)• IFO 180 - Intermediate fuel oil with a maximum viscosity of 180 Centistokes (<3.5% sulphur)• LS 380 - Low-sulphur (<1.0%) intermediate fuel oil with a maximum viscosity of 380 Centistokes• LS 180 - Low-sulphur (<1.0%) intermediate fuel oil with a maximum viscosity of 180 Centistokes• MDO - Marine diesel oil.• MGO - Marine gasoil.• LSMGO - Low-sulphur (<0.1%) Marine Gas Oil - The fuel is to be used in EU community Ports

and Anchorages. EU Sulphur directive 2005/33/EC• ULSMGO - Ultra Low Sulphur Marine Gas Oil - referred to as Ultra Low Sulfur Diesel (sulphur

0.0015% max) in the US and Auto Gas Oil (sulphur 0.001% max) in the EU. Maximum sulphur allowable in US territories and territorial waters (inland, marine and automotive) and in the EU for inland use.

$/mt FUEL GRADE

564 IFO380 (RMG380 RMH380)

589 IFO180 (RME180 RMF180)

847 MGO (DMA DMX)

570 LS380 (1.00% Sulphur)

594 LS180 (1.00% Sulphur)

847 LSMGO (0.1% Sulphur)

BUNKER PRICES

Sulphur oxides (SOx) – Regulation 14SOx and particulate matter emission controls apply to all fuel oil, as defined in regulation 2.9,

combustion equipment and devices onboard and therefore include both main and all auxiliary engines together with items such boilers and inert gas generators.

These controls divide between those applicable inside Emission Control Areas (ECA) established to limit the emission of SOx and particulate matter and those applicable outside such areas and are primarily achieved by limiting the maximum sulphur content of the fuel oils as loaded, bunkered, and subsequently used onboard.

These fuel oil sulphur limits (expressed in terms of % m/m – that is by weight) are subject to a series of step changes over the years, regulations 14.1 and 14.4:

* depending on the outcome of a review, to be concluded in 2018, as to the availability of the

required fuel oil, this date could be deferred to 1 January 2025.

Outside an ECA established to limit SOx and particulate matter emissions

Inside an ECA established to limit SOx and particulate matter emissions

4.50% m/m prior to 1 January 2012 1.50% m/m prior to 1 July 2010

3.50% m/m on and after 1 January 2012 1.00% m/m on and after 1 July 2010

0.50% m/m on and after 1 January 2020* 0.10% m/m on and after 1 January 2015

The ECA established are:Baltic Sea area – as defined in Annex I of MARPOL (SOx only);North Sea area – as defined in Annex V of MARPOL (SOx only);North American area (entered into effect 1 August 2012) – as defined in Appendix VII of AnnexVI of MARPOL (SOx, NOx and PM); andUnited States Caribbean Sea area (entered into effect 1 January 2014) – as defined in

AppendixVII of Annex VI of MARPOL (SOx, NOx and PM).Most ships which operate both outside and inside these ECA will therefore operate on different fuel oils in order to comply with the respective limits. In such cases, prior to entry into the ECA, it is required to have fully changed-over to using the ECA compliant fuel oil, regulation 14.6, and to have onboard implemented written procedures as to how this is to be undertaken. Similarly change-over from using the ECA compliant fuel oil is not to commence until after exiting the ECA. At each change-over it is required that the quantities of the ECA compliant fuel oils onboard are recorded, together with the date, time and position of the ship when either completing the change-over prior to entry or commencing change-over after exit from such areas. These records are to be made in a logbook as prescribed by the ship’s flag State, in the absence of any specific requirement in this regard the record could be made, for example, in the ship’s Annex I Oil Record Book.

The first level of control in this respect is therefore on the actual sulphur content of the fuel oils as bunkered. This value is to be stated by the fuel oil supplier on the bunker delivery note and hence this, together with other related aspects, is directly linked to the fuel oil quality requirements as covered under regulation 18 . Thereafter it is for the ship’s crew to ensure, in respect of the ECA compliant fuel oils, that through avoiding loading into otherwise part filled storage, settling or service tanks, or in the course of transfer operations, that such fuel oils do not become mixed with other, higher sulphur content fuel oils, so that the fuel oil as actually used within an ECA exceeds the applicable limit.

Consequently, regulation 14 provides both the limit values and the means to comply. However, there are other means by which equivalent levels of SOx and particulate matter emission control, both outside and inside ECA, could be achieved. These may be divided into methods termed primary (in which the formation of the pollutant is avoided) or secondary (in which the pollutant is formed but subsequently removed to some degree prior to discharge of the exhaust gas stream to the atmosphere). Regulation 4.1 allows for the application of such methods subject to approval by the Administration.

As of October 2010 there are no guidelines in respect of any primary methods (which could encompass, for example, onboard blending of liquid fuel oils or dual fuel (gas / liquid) use). In terms of secondary control methods, guidelines (MEPC.184(59)) have been adopted for exhaust gas cleaning systems which operate by water washing the exhaust gas stream prior to discharge to the atmosphere, in using such arrangements there would be no constraint on the sulphur content of the fuel oils as bunkered other than that given the system’s certification.

Bunker Fuel Analysis

• ensures marine fuel oil quality.• helps prevent costly ship engine failure, downtime, and repairs. • Analyzing marine bunker fuel also helps ship owners meet marine fuel environmental regulatory compliance. • Bunker analysis labs analyze to ISO 8217, Marpol Annex VI and other industry specifications. • Bunker fuel testing and inspection capabilities are located in major shipping centers around the world, including Singapore, Rotterdam, Shanghai, Panama, UK, UAE, and the USA.

Bunker fuel oil analysis and inspection: • Asphaltenes• Carbon Residue • Density at 15 °C, • Flashpoint • Hydrogen Sulfide IP 570• Microbes Contamination • Pour Point • Stability• Sulfur content, • Total Sediment Potential (TSP) • Kinematic Viscosity• Water Content • Bunker Fuel Chemical Contamination Screening• Cetane index, • Acid number• Oxidation stability• Cloud point• Lubricity• Appearance

ISO 8217 bunker fuel oil testing capabilities: ISO 2719: Flash Point, Pensky-Martens ISO 3679: Flash point, rapid equilibrium ISO 3015: Cloud Point ISO 3016: Pour Point ISO 3104: Kinematic viscosity ISO 3675: Density, Hydrometer method ISO 12185: Density, Oscillating U-tube ISO 3733:Water Content ISO 4264: Cetane index ISO 6245: Ash content ISO 8754: Sulfur content, energy-dispersive x-ray (XRF) ISO 14596: Sulfur content, wavelength-dispersive x-ray (XRD) ISO 103071: Total sediment ISO 10307-2: Total sediment ISO 10370: Carbon residue ISO 10478: Aluminium and silicon in fuel oils (ICP, AA) ISO 12156-1: Lubricity (HFRR) ISO 12205: Oxidation stability

ISO 8217 bunker fuel oil testing capabilities: ISO 12937: Water content, Karl Fischer titration ISO 14597: Vanadium and Nickel content EN 14078: Fatty acid methyl ester (FAME) contentEN 14214: Fatty acid methyl esters (FAME) for diesel IP 470: Aluminium, Silicon, Vanadium, Nickel, Iron, Calcium, zinc and Sodium in residual fuel oil IP 500: Phosphorus content of residual fuels by ultra-violet spectrometry IP 501: Aluminium, Silicon, Vanadium, Nickel, Iron, Sodium, Calcium, Zinc and Phosphorus in residual fuel oil IP 570: H2S Testing for Bunker Fuels (Hydrogen Sulfide in bunker fuel oils) ASTM D664-09: Acid Number ASTM D6751: Biodiesel fuel blend stock (B100)

Bunker Fuel Adulterant Testing ISO 8217• Marine bunker fuel testing detects and identifies adulterants which can harm ship engines

and violate emission regulations. • Marine bunker fuels should not contain added substances or chemical waste products, per

section 5 of ISO-8217. • Adulterated Bunker Fuel jeopardizes the safety of ships, adversely affects the performance

of machinery, and may prove harmful to personnel and the environment. • Adulterated bunker fuel incidents occur when marine bunker fuels are blended with

chemical waste products such as styrene, chlorinated solvents, and other volatile solvents.

Bunker Fuel Chemical Contamination Screening• GC/MS (Gas chromatography/Mass Spectrometry) analysis for detecting volatile

contaminants in bunker fuel - A small amount of fuel oil is heated in a sealed vial for one hour, after which time a portion of the vapour above the sample is taken for GC/MS analysis. Solvents, such as chlorinated compounds, dry cleaning fluids, and chemical wastes such as styrene, are easily detectable down to low ppm levels.

•

• additional tests

ISO-8217 bunker fuel oil tests:• Kinematic Viscosity • Density at 15 °C, ISO-3675 or ISO-12185 • Cetane index, ISO-4264 • Sulfur content, ISO-8754, ISO-14596 • Flash Point Test, ISO-2719 • Hydrogen sulfide, IP570 • Acid number, ASTM D664 • Total sediment by hot filtration, ISO-10307 1 ‐• Oxidation stability, ISO-12205 • Carbon residue, ISO-10370 • Cloud point, ISO-3015 • Pour point, ISO-3016 • Appearance• Water volume, ISO-3733 • Ash, ISO-6245 • Lubricity, ISO-12156 1‐• additional tests