Standard diesel fuel (sometimes called diesel oil) comes in two grades: Diesel-1 (D1) and Diesel-2 (D2). Diesel or Diesel fuel in general is any fuel used in diesel engines. Thats why its also commonly called as AGO or Automotive Gas Oil. Diesel fuel is a type of fuel derived from the distillation of oil that is heavier than gasoline but lighter than engine oil and heavy oil.
D1 is similar to kerosene and is lighter than D2. While D2 is sold most of the time, D1 is sold during winter in very cold climates and not sold in hot weather countries. But D2 is easily available in most countries around the world. Despite rising awareness of environmental protection, D2 remains to be a key type of fuel for use in vehicles in many countries.

In particular, demand for D2 has risen significantly in Asia over the past years as a consequence of increasing number of cars. In view of the country sustained economic growth, D2 will continue to be undersupply in the China/India and market.

WHAT IS DIESEL EN590 ?

EN590 describes the physical properties that all automotive diesel fuel must meet if it is to be sold in the European Union and Britain. Automotive diesel has national variants but the usual variants traded are EN590 and EN560 which are specified by ISO in Paris.

EN590 for diesel (in Europe) has been around for almost 20 years. However fuel, like most products, is subject to a process of continuous development and that development includes responding to legislation. The EN590 standard has been amended many times since 1993.

The EN 590 had been introduced along with the European emission standards. With each of its revisions the EN 590 had been adapted to lower the sulphur content of diesel fuel. Since 2007 this is called ultra low sulphur diesel as the former function of sulphur as a lubricant is absent (and needs to be replaced by additives).

The quality of European diesel fuels is specified by the EN 590 standard. While these specifications not are mandatory, they are observed by all fuel suppliers in Europe. Automobile diesel EN 590 is intended for application in diesel engines. Diesel motor fuel quality meets the requirements of European Standard EN 590.

For operation in the conditions of a temperate climate following marks of fuel diesel automobile EN 590 are offered: Grade C limiting filterability temperature -5 ° C; Grade D limiting filterability temperature -10 ° C; Grade E limiting filterability temperature 15 ° C; Grade F limiting filterability temperature -20 ° C.

The entire volume of produced diesel fuel quality meets the requirements for fuels for vehicles of Euro 4 and Euro 5. Low sulfur content in diesel EN 590 reduces emissions of sulfur oxides into the atmosphere, which is especially important for for inhabitants of big cities.

Some of the important revisions of the EN 590 standard have been:

EN 590:1993 the first EU diesel fuel specification. It established a sulphur limit of 0.2% in on-road and non-road diesel fuels.

EN 590:1999 this standard reflected the sulphur (350ppm) and cetane (51) specifications by Directive 98/70/EC.

EN 590:2004 Sulphur limits of 50ppm (Euro 4) and 10ppm (Euro 5) as regulated by Directive 2003/17/EC. FAME (Fatty Acid Methyl Ester) content of 5% (B5)

EN 590:2009 FAME content of 7% (B7) as regulated by Directive 2009/30/EC. This directive also adopts mandatory biofuel requirements for refiners and introduces a 10ppm sulphur limit in non-road fuels effective 2011.

WHAT IS ULTRA LOW SULPHUR DIESEL (ULSD) ?

Ultra Low Sulfur Diesel (ULSD) is diesel fuel with substantially lowered sulfur content. As of 2006, almost all of the petroleum-based diesel fuel available in Europe and North America is of a ULSD type.

There is not a single standard set of specifications and as the government mandated standard becomes progressively more strict so does the definition. The move to lower sulfur content is expected to allow the application of newer emissions control technologies that should substantially lower emissions of particulate matter from diesel engines.

This change occurred first in the European Union and is now happening in North America. New emissions standards, dependent on the cleaner fuel, have been in effect for automobiles in the United States since model year 2007.

ULSD has a lower energy content due to the heavy processing required to remove large amounts of sulfur from oil, leading to lower fuel economy. Using it requires more costly oil.