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contd....
| Table 8.10 |
| Trends in Diesel Fuel Sulphur in Some Countries |
Country/Region |
Effective date/Fuel Grade |
Maximum allowable sulphur content, % m/m |
European Union |
1994
1996
2000 |
0.2
0.05
0.035 |
Sweden |
1990
1993 EC1
EC2
EC3 |
0.20
0.001
0.005
As per the EN 590 standards |
UK |
1996
1998 (Ultra low sulphur grade, ULSD) |
0.05
0.005 |
Japan |
1997 |
0.05 |
India |
1995
2000
2005
2010 |
0.5
0.2
0.05
0.005 |
Lubricity The injection pump and injectors are lubricated by the diesel fuel itself. The heavier, high viscosity hydrocarbons and polar compounds provide natural lubricity to the diesel fuel. Hydro-treating of diesel fuel to remove sulphur also converts and removes polar compounds. Consequently, as the sulphur content of diesel fuel decreases, the lubricity of diesel fuel goes down resulting in excessive injection pump wear. A high frequency reciprocating rig (HFRR) test in which wear scar size on a standard test piece with the test fuel is measured, provides good correlation to the injection pump wear in real life. The HFRR test limit of 460µm wear scar diameter has been accepted in European diesel fuel specifications to provide adequate protection against injection pump wear.
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