DIESEL FUELS, BIODIESEL FUELS, and LUBRICITY

Diesel engines can burn a wide range of hydrocarbon fuels ranging from light distillate fuels such as No 1 Diesel to heavy residual fuels such as Bunker C or No. 5 Fuel Oil. New regulations for Diesel Motor Fuel dictate low sulfur levels.

Diesel fuels for Marine, Railroad, or Power Plants have other specific requirements and are discussed in later sections.

Biodiesel Fuels are included in this section since they can be blended with straight distillate products to achieve the low sulfur requirements now regulated for motor diesel grades. Diesel Fuel Lubricity is emphasized because it has become a prominernt factor in low sulfur grades.

 

DIESEL FUELS, ASTM D 975

This specification covers five grades of diesel fuel oils that are suitable for various types of diesel engines:

•  Low Sulfur Grade 2-D General Purpose fuel for automotive diesel engines, < 0.05% Sulfur

•  Low Sulfur Grade 1-D Special Purpose higher volatility fuel for automotive diesel engines, < 0.05% S

•  Grade 2-D General Purpose distillate fuel for automotive diesel engines, <0.5% Sulfur

•  Grade 1-D Special Purpose higher volatility fuel for diesel engines, <0.5% Sulfur

•  Grade 4-D Heavy distillate fuel and blends with residual fuels, < 2.0% Sulfur

BIODIESEL FUEL, B 100 BLEND STOCK, ASTM D 6751

Biodiesel Blend Stock is derived from vegetable oil and animal fat and may be blended with petroleum distillate fuels to achieve regulated levels of sulfur or aromatics. B-100 can be used as a blend component with Diesel Fuel Oils defined by ASTM D 975, Grades 1-D and 2-D and Low Sulfur 1-D and 2-D. Presently, Biodiesel B 100 Blend Stock is available in two grades:

•  S15 Sulfur Content of <15 ppm

•  S500 Sulfur content of <500 ppm

DIESEL FUEL LUBRICITY

It is important to verify the lubricity of low-sulfur diesel fuels and blends to assure satisfactory performance as a fuel in diesel engines. Lubricity of a diesel fuel describes the ability of the fluid to affect the friction between moving metal surfaces. Low-sulfur diesel fuels need certain additive packages to compensate for those hydrocarbons that provided the fuels natural lubricity.