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Super fine - Sasol’s Euro 4 ultra low sulphur diesel already available at forecourts.

Sasol is South Africa's international diesel success story with a technological edge that puts it decades ahead of many of its competitors. With 'green' diesel now a mandatory requirement for the running of new vehicles in South Africa, Sasol is the first of the local oil companies to offer Ultra Low Sulphur (ULS) diesel (50ppm) to truckers. Paul Collings shot some probing questions at Sasol's John Fitton, manager technical services, Sasol Technology Fuels Research.

PC: Has Sasol conducted tests on South African trucks using low sulphur diesel (500ppm & 50ppm)?
JF: Sasol has conducted a number of studies over the past number of years on low and ultra low sulphur diesel. The most recent being conducted in collaboration with Barloworld Logistics and Daimler Chrysler on long haul trucks where significant extensions in drain intervals were achieved - up to five times - while extending the engines life.

PC: Can the claims of extended oil change intervals be verified locally?
JF: There is significant information internationally in this regard, as well as a number of trials that have been conducted locally. With the reduction in sulphur, there is a reduction in the soot loading of the lubricant and hence an extension can be achieved. The question is, to what extent. This needs to be verified by the OEM, but can be very easily done under local conditions.

PC: Will there be a price difference between 500ppm and 50ppm diesel?
JF: Yes, there is currently a price difference of about 8 cents per litre between Low Sulphur (LS) and ULS diesel. ULS diesel has the higher price tag of the two due to higher production costs associated with sulphur reduction at refineries, but it is a first-class product from an emissions viewpoint.

PC: Will lubricity levels be adequate in new diesel or will an additive be essential to keep trucks running smoothly in our harsh operating environment (both in driving style and atmospheric conditions)?
JF: As the diesel sulphur specification is reduced, so the diesel streams need to be hydro processed. The sulphur is removed but other polar compounds are also removed. These polar compounds provide the required lubricity. Therefore, for diesel with a sulphur content of 500 ppm and below, the lubricity needs to be replaced with the use of additives. This is done at the refinery and the product is tested before being released into the market place. No additional aftermarket additives are required - if good housekeeping is complied with. 

PC: Diesel contamination (dust, water, algae, bugs etc) is a known destroyer of modern injector units. Is Sasol doing anything in the way of filtration at 'point of sale' or at bowsers of large truck fleets?
JF: We have installed filters at all our depots to reduce possible contamination that may occur within the logistic chain between refinery gates and depots. In addition, filters are fitted to pumps. Water management is critical and if systems are kept dry, no problems will be experiences with algae etc. Regular dipping with water finding paste is required for this. 

PC: What can you recommend to truck owners as far as fitting filters is concerned (primary and secondary as well as water traps)?
JF: Truck owners normally have fuel storage facilities (e.g. tanks) at their depots and it would be recommended that filters be installed at those facilities. On-vehicle management is also critical as often most of the product contamination (water and dirt) is from within or on the vehicle. On-vehicle filter management is therefore critical and filters should be replaced regularly. The OEM should be consulted with regard to the required filters on the trucks. This must also be followed by good housekeeping at storage facilities.

PC: Now that the Air Quality Act is a reality, do you have any information regarding the standardisation of emissions standards on trucks? Specifically, when will SANS put standards in place?
JF: There are specification requirements for newly launched (homologated in 2006) vehicles while specifications for the vehicle parc are currently being set. 

PC: Do you foresee any incentives coming from government to encourage emissions compliance within the transport sector?
JF: Yes, this is a critical element in the drive for an improved environment and better air quality. Large investment is being made by the oil industry and without the associated improvement in vehicle emissions - specifically maintenance - there will only be limited improvement in the air quality. There is also a drive to reduce fuel consumption (energy efficiency) in the transport sector.