D6 fuel, also known as residual fuel oil (RFO), bunker fuel is a high-viscosity fuel used primarily in large marine engines and industrial furnaces. Due to its thick consistency and high pollutant content, it requires preheating before use. In the marine industry, it is also referred to as “Bunker C.” The Platts code “PKABA00” specifically denotes D6 Marine Fuel, a classification used for heavy residual fuel oil in shipping and industrial applications.
Uses of D6 fuel
- Used in large ships
- Used for generators
- Used for vessel bunkering
Characteristics of D6 fuel
By partnering with the industry majors and emerging alternative fuels producers, our physical supply is complemented by closely monitored refining, terminal storage and distribution of the highest quality standards.
The most common bunker grades supplied are:
| Specifications | ||||
| HFO | 2005 | 2010 | 2017 | |
| VLSFO | 2005 | 2010 | 2017 | |
| MGO | 2005 | 2010 | 2017 | |
In addition to this, we also meet specific wishes on quality of intermediate grades, not specifically mentioned in ISO 8217.
Bunker fuel specifications can vary depending on the type of fuel and the standards set by organizations like the International Maritime Organization (IMO) or regional regulations. Below is a general overview of the specifications for the most common bunker fuel grades: Heavy Fuel Oil (HFO), Very Low Sulfur Fuel Oil (VLSFO), and Marine Gas Oil (MGO). Note that the exact specifications may vary by supplier and region.
Heavy Fuel Oil (HFO)
HFO is a residual fuel oil commonly used in marine engines. It is a viscous fuel with high sulfur content, typically used in ships with traditional engines.
Key Specifications:
- Density at 15°C: 980–1010 kg/m³
- Viscosity at 50°C: 180–700 cSt (centistokes)
- Sulfur Content: Up to 3.5% (pre-IMO 2020), now limited to 0.5% in most regions under IMO 2020 regulations.
- Flash Point: Min. 60°C
- Pour Point: Varies, typically -6°C to 24°C
- Carbon Residue: Up to 18–22%
- Ash Content: Up to 0.2%
- Water Content: Up to 1.0%
Very Low Sulfur Fuel Oil (VLSFO)
VLSFO is a cleaner-burning fuel introduced to comply with IMO 2020 regulations, which limit sulfur content to 0.5% globally (outside Emission Control Areas).
Key Specifications:
- Density at 15°C: 900–990 kg/m³
- Viscosity at 50°C: 10–180 cSt
- Sulfur Content: Max. 0.5% (compliant with IMO 2020)
- Flash Point: Min. 60°C
- Pour Point: Varies, typically -6°C to 24°C
- Carbon Residue: Up to 10–15%
- Ash Content: Up to 0.1%
- Water Content: Up to 0.5%
Marine Gas Oil (MGO)
MGO is a distillate fuel with low viscosity and sulfur content, often used in auxiliary engines or in Emission Control Areas (ECAs) where sulfur limits are stricter (0.1%).
Key Specifications:
- Density at 15°C: 820–900 kg/m³
- Viscosity at 40°C: 2–6 cSt
- Sulfur Content: Max. 0.1% (in ECAs) or 0.5% (outside ECAs)
- Flash Point: Min. 60°C
- Pour Point: Typically -6°C to 0°C
- Carbon Residue: Up to 0.3%
- Ash Content: Up to 0.01%
- Water Content: Up to 0.1%
Comparison of Key Parameters (2005, 2010, 2017, and Post-IMO 2020)
| Parameter | HFO (Pre-IMO 2020) | VLSFO (Post-IMO 2020) | MGO (ECA Compliant) |
|---|---|---|---|
| Density (kg/m³) | 980–1010 | 900–990 | 820–900 |
| Viscosity (cSt) | 180–700 | 10–180 | 2–6 |
| Sulfur Content | Up to 3.5% | Max. 0.5% | Max. 0.1% |
| Flash Point (°C) | Min. 60 | Min. 60 | Min. 60 |
| Pour Point (°C) | -6 to 24 | -6 to 24 | -6 to 0 |
| Carbon Residue | Up to 18–22% | Up to 10–15% | Up to 0.3% |
| Ash Content | Up to 0.2% | Up to 0.1% | Up to 0.01% |
| Water Content | Up to 1.0% | Up to 0.5% | Up to 0.1% |
Notes:
- IMO 2020 Sulfur Cap: Since January 1, 2020, the global sulfur limit for marine fuels has been reduced to 0.5% (from 3.5%), except in ECAs where the limit is 0.1%.
- VLSFO Adoption: VLSFO has become the most widely used bunker fuel post-IMO 2020 due to its compliance with sulfur regulations.
- MGO Usage: MGO is primarily used in ECAs or by vessels equipped with scrubbers to meet stricter emission standards.
