Sulphur’s role in diesel fuel
With an increase of more fuel-efficient diesel-powered vehicles on our roads, there are questions being asked about the sulphur content in the fuel and what it does.
Almost all crude oil-derived fuels contain some level of sulphur.
Sulphur has lubricating properties but the downside is it also increases exhaust emissions in the form of sulphur dioxide.
Removing or reducing the amount of sulphur from diesel has a couple of side effects.
The lubricating properties of the fuel are reduced but this has been addressed by specifying a minimum lubricity standard.
The second effect is a reduction in the fuel’s aromatic content.
Aromatics add to exhaust emissions, so it’s desirable to keep levels to a minimum.
Aromatics also have a swelling effect on some seal materials that were once commonly used in fuel pumps.
Reductions in aromatic content can cause the seals to shrink slightly and, depending on their condition, they may leak.
In the early 2000s diesel sulphur content was 5000ppm (parts per million), this was reduced in 2009 to 10ppm, a massive reduction.
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The information in this article has been prepared for general information purposes only and is not intended as legal advice or specific advice to any particular person. Any advice contained in the document is general advice, not intended as legal advice or professional advice and does not take into account any person’s particular circumstances. Before acting on anything based on this advice you should consider its appropriateness to you, having regard to your objectives and needs.