1. What It Is:
Marine Diesel Oil (MDO) is a blended marine fuel consisting of distillates and small amounts of residual fuel. It is heavier than Marine Gas Oil (MGO) but lighter and cleaner than Heavy Fuel Oil (HFO), commonly used in medium- to low-speed marine engines.
2. Key Properties:
- Sulfur Content:
- Varies based on region
- Low Sulfur MDO (LSMDO): ≤0.5% (to comply with IMO 2020)
- Density: ~0.87–0.89 kg/L
- Flash Point: >60°C
- Viscosity: Higher than MGO, but lower than HFO
- Color: Darker than MGO, can appear brownish
3. Applications:
- Used in main engines, auxiliary engines, and boilers
- Suitable for ocean-going ships, ferries, and cargo vessels
- Often used outside Emission Control Areas (ECAs)
4. Advantages:
- Less costly than MGO
- Compatible with older marine engines
- Easier handling than HFO (no extensive heating needed)
5. Limitations:
- Contains some residuals, so it’s not as clean-burning as MGO
- May require treatment before use (e.g., filtering, settling)
6. Compliance:
- Must meet ISO 8217 marine fuel standards
