Ultra-Low Sulfur Diesel (ULSD) – EN 590

Ultra-Low Sulfur Diesel (ULSD) conforming to EN 590 is the global benchmark automotive diesel fuel for modern compression-ignition engines. It is engineered to meet strict environmental regulations while delivering high combustion efficiency, engine protection, and compatibility with advanced emission-control technologies. EN 590 ULSD is mandatory across the European Union and widely adopted in Asia, the Middle East, Africa, and international export markets.

This grade supports Euro IV, V, and VI emission norms, making it suitable for passenger vehicles, commercial fleets, construction machinery, agricultural equipment, and power-generation systems where high-quality diesel is required.

Technical Specifications (Typical EN 590)

ParameterTypical Value
Sulfur Content≤ 10 ppm
Cetane NumberMinimum 51
Density @ 15°C820 – 845 kg/m³
Kinematic Viscosity @ 40°C2.0 – 4.5 cSt
Flash Point≥ 55°C
Distillation (95% recovered)≤ 360°C
PAH Content≤ 8%
Ash Content≤ 0.01%
Water Content≤ 200 mg/kg

Chemical & Physical Characteristics

Sulfur & Emissions Profile
The ultra-low sulfur content dramatically reduces: Sulfur Oxides (SOx)
Acid rain formation
Particulate emissions It also prevents catalyst poisoning, extending the life of DPFs and SCR systems.

Cetane Quality:
A higher cetane number ensures: Faster ignition delay
Smoother cold starts
Reduced engine knock
Lower NOx and unburnt hydrocarbon emissions

Lubricity Enhancement:
Deep hydrotreating removes natural lubricants; therefore: Lubricity additives are mandatory
Prevents wear in high-pressure common-rail fuel injection systems
Protects fuel pumps and injectors under extreme operating conditions

Oxidation & Storage Stability:
EN 590 ULSD is stabilized using: Antioxidants to prevent gum formation
Corrosion inhibitors to protect tanks and pipelines
Biocide additives (optional) to prevent microbial growth during storage

Refining & Production Process

Primary Processing
Atmospheric distillation to obtain middle-distillate fractions
Severe hydrotreating (HDS – Hydrodesulfurization) to reduce sulfur below 10 ppm
Secondary Upgrading
Hydrocracking (optional) to improve cetane and reduce aromatics Dewaxing to enhance cold flow properties Final Blending
Cetane improvers Cold flow improvers (CFPP enhancers) Lubricity additives Anti-foam and demulsifiers

Cold Flow & Climate Performance

EN 590 defines seasonal and climatic grades to ensure reliable operation:
Climate GradeCFPP (°C)
Summer0 to −5
Winter−15 to −20
Arctic−32 to −44

These grades ensure reliable cold starts, no fuel gelling, and smooth fuel-filter performance across diverse climates.

Compatibility with Bio-Components

EN 590 allows up to 7% FAME (B7) biodiesel blending
Fully compatible with modern diesel engines
Reduces lifecycle carbon emissions
Requires enhanced oxidation and water-management additives

Applications

Automotive & Transport
Passenger vehicles Trucks, buses, logistics fleets Industrial & Commercial
Construction equipment Mining machinery Agricultural tractors Power & Backup Systems
Diesel generators Mobile and standby power plants

Environmental & Regulatory Compliance

Meets EU Fuel Quality Directive
Supports Euro IV / V / VI emission standards
Reduces greenhouse gas emissions
Lower toxic exhaust particulates

Advantages Over Conventional Diesel

Cleaner combustion
Lower engine maintenance costs
Extended engine and after-treatment life
Improved fuel efficiency
Better cold-weather operability

Trade & Logistics Information

Common Export Forms: Bulk, ISO Tank, Flexitank
HS Code: 2710.19 (indicative)
Typical Origin: Europe, Middle East, Asia refineries
Shelf Life: 6–12 months (with proper storage & additives)