Page 40 - Energize August 2022

VIEWS AND OPINION

Doctored diesel is dangerous

by John Evans, WearCheck

In response to an article that appeared in Fin 24 on 15 June this year, Gwede Mantashe, the minister of mineral
resources and energy, warned of the use of illuminating paraffin (IP) to doctor diesel in an attempt to defraud the
revenue services and increase profits. This article provides some background to this practice, the deleterious

effects it can have and the various methods for testing diesel for the presence of illuminating paraffin.

iesel can be subjected to a variety of chemical and physical tests in the fuels
laboratory. One of the most common and important things to look for is
Dcontaminants, the most common of which are dirt and water.
Diesel can also be contaminated with other fuels and solvents, in particular illuminating
paraffin or IP as it is known. IP is a readily available power source for domestic lighting,
heating and cooking. Chemically it is very similar to diesel but because it is used as a
domestic power source, it is not subject to the taxes and levies that diesel is, making it
cheaper than diesel to buy.
The less-than-honest members of our society have taken to doping diesel with IP, and
because it is so similar to (but not exactly the same as) diesel, a diesel engine will run quite
happily on a diesel/IP mixture at less than the cost of diesel alone. Although the engine will
run without problems in the short term, in the long term the IP will be quite damaging to
the engine.
This is because IP has a lower viscosity and less lubricity than diesel and damage will
result from increased wear to the components of the fuel system.
Although the price difference may not be huge (about R25/l for diesel and about
R20/l for illuminating paraffin) if you think of the thousands of litres of diesel used every John Evans
day, doping diesel with 10% or 20% illuminating paraffin represents a large cost saving for
nefarious operators and significant loss of income for the revenue services (SARS). cannot tell you is how much IP is present.
The effects of IP contamination on diesel are that the viscosity, density and flashpoint What is important to mention, is that if
will decrease, and the sulphur concentration will increase. Also, low viscosity and lubricity the IP came from a source which was not
of IP mean increased wear of fuel system components. Low density means you get less marked, for example, from across our
efficiency, which means that more litres of fuel are required for the same number of borders, where markers are not used,
kilometres travelled. Low flashpoint could become a safety issue and elevated sulphur then no marker will be detected, yet the
could impact the emission controls of modern engines and increase combustion by- sample could still be contaminated, but
products being introduced into the lubricating oil, reducing its ability to lubricate the not by enough to fail the other physical
engine adequately. tests of viscosity, density and flashpoint
Interestingly enough, small amounts of IP may not affect the properties of diesel that may be carried out.
enough for it to fail the Bureau of Standards specification SANS 342 so, IP can be present, Further testing is possible, however.
yet the fuel will still pass the specifications of SANS 342. In fact, IP is often legally added The diesel sample can be sent to a
to diesel in small amounts by the refineries as it helps prevent the diesel from waxing SARS-approved laboratory, where a gas
(freezing) during the cold winter months in-land. But doping diesel with IP, in the long chromatography–mass spectroscopy
term, is not a good idea and it is also illegal. instrument may be used. This instrument
Because this type of doping represents a loss of income for SARS, a chemical can measure the actual amount of the
marker has been added to illuminating paraffin sold in South Africa. The marker comes marker in the fuel and, from that, it is
from Authentix, an American company which specialises in brand protection and anti- possible to calculate the actual amount
counterfeiting. This marker is added to IP at a precise concentration before the product of IP in the diesel fuel.
leaves the refinery. The reason for having two levels
It is possible to test for this marker using a lateral flow test kit, similar to those used for of testing is because (at the time of
testing for Covid or even pregnancy. The result is a simple yes or no: the marker either was publishing), the lateral flow test kits cost
or was not detected. The test kit is very easy to use and takes hardly any time at all. What it about R500, whilst the actual percentage

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