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Past Issues

July  2004

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South Africa's diesel finds itself in interesting times right now and is seemingly enjoying mixed fortunes. On the one hand, it's being earmarked as the fuel of choice for internal combustion engines, including cars, because of its bio-friendly potential. On the other hand, locally produced diesel continues to be stigmatised as a toxic, poor performing fuel dispensed by unscrupulous operators. While our diesel manufacturers engage in ongoing research and development to provide cleaner-burning product that is suitable for new diesel injection systems, engines continue to fail. What is the real deal regarding diesel quality? How can truckers improve their fuel? Where is the diesel industry headed? FleetWatch sent Paul Collings out to sniff the fumes.

Remember Dallas?
It must be stated, on the surface, that the diesel business is a bit like a soap opera. There are so many players involved and many seem to have conflicting interests, from oil refiners to diesel distributors and retailers, to engine manufacturers, engine repairers and after-market accessory/additive suppliers, to environmental agencies and laboratories, and ultimately the end users, trucking companies. All of them have a deep vested interest in not only the quality of our diesel and its environmental impact but also its price. 

There are problems, it seems, in 'diesel-land' (greed, lack of awareness and communication, economies of scale, etc) and I hope that this article will go some way to addressing them and perhaps open a channel for debate about diesel and how we can all work together to ensure it burns cleaner, costs less and creates more jobs for all South Africans. 

What's wrong with SA diesel?
This all depends on what you mean by SA diesel - how far down the distribution chain you choose to analyse it. Refineries insist that the diesel that leaves their plants in pipes or fuel tankers is pure, uncontaminated and compliant with Euro1 standards. They also claim that their diesel is suitable for all new common-rail injector engines.

When diesel engines fail, truck owners look for a culprit and more often than not, fingers are pointed at the diesel manufacturers. The reality is that many potential evils exist within a tank of diesel and the line to the combustion chamber, not to mention what comes out the exhaust pipe. To further complicate matters, human intervention and negligence exacerbate deterioration in diesel quality.

Can we blame history, maybe?
Just a decade ago, South Africa's road transport industry was predominantly powered by ADE (Atlantic Diesel Engines) technology. These engines were relatively low-tech in nature (mechanical injectors) and their ability to combust on low-grade diesel made them solid, reliable workhorses, albeit smoky. They were also easy to repair.

When democracy reached our shores in 1994, ADE closed its doors (in 1996) making way for imported diesel engine technology, most notably fuel injection systems, electronic controls, variable-geometry turbochargers and exhaust after-treatment devices. While fuel efficiency played a critical role in the development of these new technologies, stricter emissions legislation in the USA and Europe were really driving the 'truck'. The upshot was an entire local diesel-powered transport industry faced collapse because of a lack of know-how with regards to the maintenance of these new diesel-engine technologies. Truck manufacturers were obliged to fit their vehicles with factory-produced engines and import them to South Africa. Local diesel mechanics, however, were ill equipped to service these new electronic devices. Disaster loomed. 

At the heart of new diesel engines is 'common-rail' or 'unit-injector' designs (a common feature of which is far higher injection pressure than the old mechanical systems), coupled with precise electronic control of injection timing. Servicing these electronic components hasn't been easy in South Africa. Diesel macs have had to learn how to use a computer! A laptop nogal! 

A prime example of our ability to adapt to change is Frank Testa, MD of DPA Diesel, a diesel motor repair company based in Booysens, Johannesburg. He and his team are going stronger than ever after more than twenty years in the business of repairing diesel engines, of whatever nature. Testa's testimony is: "Ten years ago we all thought we were drowning in a dying industry. We panicked. Then we thought about it. We realised the diesel business wasn't dying, it was simply changing. We partnered with global diesel leaders like Bosch and learnt how to repair and service the new injection systems."

Who is SA diesel's JR Ewing?
Despite Testa's success, the feeling among fleet operators in general is that locally manufactured diesel is not keeping pace with the high-tech engines in the trucks they use. The question is: Who is SA diesel's J.R. Ewing and who's gonna shoot him?

When it comes to 'diesel bad guys' we're looking at a proper rogues gallery. Here are some interesting facts, courtesy of Ron Mattig, Clear Fuel Technologies: We service our vehicles roughly two to three times more frequently as the same models in Europe, Japan, USA and the UK. Injectors and pumps require frequent changing or overhauling. Our vehicles smoke excessively and suffer from clogged filters. Numerous motor manufacturers are unwilling to launch new diesel models here due to concerns over fuel quality. Fuel consumption figures on the same models in Europe, Japan, USA and UK differ by as much as 10% compared to local models. 

To get to the bottom of the 'mystery' and draw up a hit-list, FleetWatch spoke to 'diesel detective' Mike Bond, technical director of Eurotype, an independent fuel testing laboratory:

"Fuel quality can be defined in two ways - the baseline quality of the fuel as it leaves the refinery and the degradation that occurs during the distribution and retailing process. Generally, baseline fuel quality is improving slowly, although we are a long way behind the rest of the world in terms of sulphur. From the ongoing handling and retailing complaints, I think little has been done to address the degradation issue."

Bond goes on to highlight the issues around diesel refinement and pinpoint the 'culprits'.
  

When diesel engines fail, truck owners look for a culprit and more often than not, fingers are pointed at the diesel manufacturers

Sulphur
"Sulphur is present to a greater or lesser extent in all crude oils and has to be removed as part of the refinery process. Its presence has been tolerated until recently because it generally improves the lubricity of diesel (important to prevent damage to high-pressure pumps and injectors) but alternatives have been developed and are already in use.

"During the combustion process, sulphur combines with oxygen to form sulphur dioxide. This then combines with water to form sulphuric acid which, once released into the atmosphere, falls as acid rain. In an engine, the acid attacks the additives in the oil, reducing the total base number until the engine is unprotected. Then corrosion damage to metal components occurs, especially those close to the combustion chamber and this significantly reduces engine life.

As the degraded oil can no longer function properly, there is also a build-up of gums and varnish, (especially in the highly thermally loaded areas like pistons and rings), abnormal ring/bore wear occurs, ring sealing is compromised, blowby increases, more exhaust gas gets into the crankcase, the acid build-up accelerates and it becomes a vicious circle that can end in total engine failure."

Another problem with sulphur - and one that particularly concerns Eurotype - is its environmental impact. Sulphur is known to influence the emissions of fine particulate matter (PM) through the formation of sulphates, both in the exhaust stream and even in the atmosphere. The small particles emitted by diesels are a known carcinogen, which is why the developed nations have strict limits on PM emissions. These limits, and the corresponding limits on gaseous emissions, necessitate the use of catalytic converters and particulate traps.

Sulphur compromises the efficiency of both catalyst-based and particulate filter-based exhaust treatment systems, which is why the levels in overseas fuel have been legislated down to the absolute minimum. As limits become tighter, there will be a move to diesel with zero sulphur content.

"The fuel companies may point out, quite correctly, that sulphur aids in fuel stability and lubricity but experience elsewhere has clearly demonstrated that alternative technologies exist to compensate for the removal of sulphur. It is a matter of making the investment in the refining process to accomplish this which, in turn, is a matter of political will to do something about the environmental threat. Either government must wield a big stick in terms of legislating the quality of diesel; or they must dangle a carrot, in the form of tax incentives, to get the refineries to play ball," says Bond.

Inorganic matter
Bond stresses that inorganic matter like metals, rubbers, plastics and dust that are introduced by the mechanics of transportation are problematic. They come from the rubbing together of tank, valve and piping components and from the need to have tank venting to allow filling and drainage.

"This debris accumulates as sludge in fuel tanks and it clogs fuel filters. If the particles are small enough, they will pass through the filter medium and into the fuel pump where they can cause excessive wear and degradation of injection equipment efficiency. Inorganic debris can be minimised by cleanliness of transportation equipment (sealing fuel hoses on tankers, for example), regular inspection of all tanks, valves and hoses and by fitting suitable vent filters. The filling station can also assist the process by fitting filters to the dispensing pumps, and ensuring these filters are regularly changed."
  

Either government must wield a big stick in terms of legislating the quality of diesel, or they must dangle a carrot, in form of tax incentives to get refineries to play ball

Water
Water normally accumulates from condensation, especially if bulk storage tanks are run close to empty. Sometimes, according to allegations, it is introduced by unscrupulous filling station operators to get fuel out of the 'dead zone' at the bottom of the tank specifically designed to accumulate condensate for safe disposal. In South Africa, the frequent swings in fuel price contribute to the problem as filling stations tend to run tanks low when a price reduction is imminent to avoid financial losses.

According to Bond, water acts together with the acidic waste products of microbes to cause corrosion and is the means by which the atmospheric spores become active biological populations. It is thus a catalyst and removing water would significantly reduce the problems experienced by vehicle owners or operators with contaminated diesel.

"The effects of water accumulation can be minimised by keeping tanks as full as possible and by regular dipping to check amounts of water present. Ideally, a bypass filter system should be installed that continually removes water from the bottom of the tank."

Bond says the problem of water is the one over which the filling station operator has the most influence. "Education in the care and preventative maintenance of diesel storage facilities is critical, and a commitment to the inspection and cleaning requirements would go a long way to easing the problem."
  

Forecourts go laundramatic  All major fuel suppliers are now including detergents, anticorrosives and anti-foaming agents in their diesel to help new-generation diesel engines run smoother.

Organic microbes
Organic microbes such as bacteria, fungus and yeast that live on the fuel/water interface and can feed off the hydrocarbons present in the fuel help contaminate diesel too. They are carried in the air as spores and large numbers are present in the atmosphere at all times. It is normal to have a small population of these 'bugs' in diesel tanks and in these small numbers they have no detectable side effects.

"However," says Bond, "given additional water and the right temperature range, they will reproduce rapidly and exponentially grow the population. They feed on the fuel and develop a protective film around themselves, generally known as slime. This slime clogs fuel filters, acting in conjunction with inorganic debris to restrict flow and reduce performance. Slime can also form in fuel lines and injector nozzles causing uneven atomisation and poor combustion. Some bugs also release acidic enzymes that are carried through the fuel system and which cause corrosion of fuel tanks, lines, pumps and injectors."

Bugs can be treated with biocides but merely killing them does not make the problem go away. Firstly, the dead bugs drop to the bottom of the tank and combine with water and inorganic debris to form sludge. Secondly, the slime protection will ensure that at least some bugs survive, so when the biocide concentration drops and conditions are right, they rapidly regenerate. More biocides are needed as more sludge is formed and the best solution then becomes a complete drain and clean of the fuel system.

Petrol
Here's an interesting one. Bond reckons petrol is usually introduced at the refinery through failure to flush pipelines when switching between different product (this also happens the other way, i.e. diesel finds its way into petrol). Negative effects are a reduction in viscosity, lubricity and cetane number.

"The first effect is manifested in leaking plungers and seals and possible premature injection causing engine knock and consequent damage; or after injection, causing excessive exhaust temperatures with the risk of valve/manifold/turbocharger failure. Lowered lubricity brings the risk of pump and injector wear, metal-to-metal contact and seizure of pump plungers, rollers or cams. Lowered cetane number increases the tendency for diesel knock, the resultant peaks in cylinder pressure then causing damage to pistons, rings cylinder head, gaskets and/or bearings."

Paraffin
Paraffin is usually introduced deliberately to increase fuel volume at low cost; sometimes - in the colder areas - to reduce the waxing tendency of diesel. The effects are similar to petrol, in all three of the mentioned parameters, the end effect being a substantial risk of serious damage to fuel injection equipment or engine," says Bond.

Making 'Southfork' a safer place
Bond goes on to advise: "Operators can do a lot to ensure they are treating their high-pressure diesel fuel system with the correct level of respect. They have to properly understand the technical parameters of new high-pressure diesel engines and the fuel they are using.

"As with the filling station operator, education is a primary consideration. Any truck operator must be totally familiar with the vehicle he or she is operating in terms of its fuel system. They must know where the fuel filter is, how often it should be changed and whether there is a water trap. An understanding of the potential hazards, from where they may originate and how to avoid or compensate for them is very important.

"Finding a good filling station would also be a good idea. One with a high turnover of fuel is less likely to have water or other contaminants in its fuel. The general condition of the site should give an idea of the emphasis placed on maintenance and upkeep; for example, dirt and rubbish scattered over the forecourt or pumps with chafed hoses and damaged nozzles should ring warning bells.

"They should also appreciate that the presence of water, debris or bugs has a significant influence on the lubricity of the fuel (its ability to keep two surfaces apart from one another) and that, in the high-pressure side of the fuel injection equipment, the only thing that is lubricating these parts is the fuel itself. The tendency in today's modern diesel engines with common rail or unit injector systems is towards higher injection pressures and this is placing more emphasis on the lubricity of the fuel."

Says Bond: "I also don't think many drivers appreciate the parameters under which these engines operate, or the fine line that exists between happy trucking and catastrophic failure. Education of drivers is also paramount to success."

Bring in 'Kristin'
While the chemists at the diesel labs strive for lower sulphur content, NOX emissions etc, business goes on as usual in the transport industry. The nagging question is - how do fleet managers and truckers in general make sure the fuel they buy doesn't kill their workhorses? 

Load 'em slugs baby
On this point, a whole new industry has sprouted over the last ten years because of the disparity between local diesel and new injector technology. And thank the saints for that! Be they filters, additives or repair technologies and services, they're out there to make sure our trucks keep moving.

At present, while the legislators get their papers in a row, truckers, it seems, must bear the extra costs of keeping their diesel engine-friendly. Whether it's fitting a new filter, chucking in a lubricity additive or servicing injectors with hi-tech gear, 'hired guns' are out there to keep wheels turning.

Filters
According to Ron Mattig of Clear Fuel Technologies, a diesel engine fuel system is a 'closed loop' cycle system. The engine continuously takes fuel from the tank and filters that fuel before it goes to the injectors. The surplus fuel, not used for combustion, returns back to the tank through the return line.

"One would expect that this continuous filtration process would keep each and every diesel fuel tank absolutely spotless," says Mattig. "However, we all know better. The larger the tank, the more sludge, contamination and fuel degradation we experience. Traditional approaches to restoring fuel quality have been both mechanical and chemical. Filters and separators cannot be avoided and are essential items on the mechanical side but tank cleaning is time consuming and costly. Chemical methods include biocides, which only deal with microbial contamination and can produce toxic tank sludge and be dangerous to handle. However, none of these are adequate solutions and are only symptom-driven patches. We are still left having to change filters, clean tanks, replace injectors and deal with emissions." 

Mattig's company markets the Algae-X Fuel Conditioner, which is installed in the fuel line between the tank and the filter. "It continuously treats and conditions the fuel directly before combustion," says Mattig, "and before it returns to the tank. It optimises fuel quality, and cleans the entire fuel system by simply running your engines." 

According to Craig Pretorius of Filter Focus, "two-micron filtration is no longer sufficient in our harsh African conditions. Remove the dirt effectively down to below one-micron and maintain the levels of water in solution down to well below 50 parts per million and most of the market's nightmares will disappear. We are able to filter out diesel contamination to below one-micron and remove water in solution to below 20 parts per million, hence our term 'polished diesel'."

Additives
With sulphur levels decreasing steadily in local diesel, the thought is there that truck operators should compensate for the resultant lowered lubricity levels by adding a lubricant to their fuel line. An interesting new product called Fuel Effect is making waves in this sector of the diesel market.

Additive Maverick  Andre Steyn of Logic 7 who are marketing new product ‘Fuel Effect’.

According to Andre Steyn, MD of Logic 7, the company marketing the product in South Africa, "Fuel Effect opens the structure of the diesel via the incorporation of a long unbranched hydrocarbon, which interfaces with the normal carbon chain increasing lubricity and improving the ignition properties of the fuel. It helps the engine, the pump and the injectors run cooler and smoother." Steyn says the product also improves exhaust emissions, considerably lowering soot levels.

Fuel fraud preventatives
Theft of diesel is rife in the transport industry and fleet operators must go to every possible length to ensure they're getting all the fuel they're paying for. Apart from locking systems, technologies like vehicle tagging systems create a real-time interface between vehicle fuel tanks and office computers. 
  

Bye Bye Pump Jockey  New tagging technology will do away with cash and human intervention in the fuel-filling process, eradicating fuel fraud in the process.

Barloworld Logistics, suppliers of logistics and supply chain management solutions, have invested in a vehicle tagging system in order to bring efficient fuel management to its customers' and its own operations. After fitting AFS Group's eFuel vehicle tagging system, fuel theft and card fraud at Barloworld has been significantly reduced.

Using eFuel, Barloword Logistics has automated the fuel requirements of its 235 vehicle fleet and fuel depots at nine sites around the country. Data produced by the vehicle tagging software is automatically fed into the new ERP system for detailed analysis and reporting. 

David Froman, executive chairman of the AFS Group, says automated fuel procurement is about effective management, convenience and eliminating fraud. "Fuel management makes sense. Companies stand to save a fortune if they manage their fuel more efficiently. Using vehicle tagging technology, drivers don't have to carry cash and there are accurate and detailed records of how fuel is used."

The system works by fitting vehicles with an electronic tag. When the nozzle from a fuel pump is inserted into the vehicle, a computer system records how much fuel was dispensed, where and when and all information including the vehicle's odometer reading. Because it's an in-house fuelling system there's no payment.

A growing number of retail fuel suppliers like Shell, Engen, Total, Sasol and Caltex are equipped with eFuel equipment in over 1 000 locations countrywide. Using their own brand names for the product, the oil companies are marketing it directly to fleet operators. By the rapid adoption rate of the system, it seems clear that this high-tech solution stops the buck properly!

The diesel injector doctors
It's now common knowledge that dirty diesel kills engines. Even with effective filtration and additives, diesel in South Africa still clogs injector nozzles. Regular servicing of pumps and injectors is recommended to complete the spread of measures necessary to keep a modern diesel engine healthy. Says Frank Testa of DPA Diesel: "New common rail systems have to be serviced more regularly than older types of injector units. They have such critical tolerance levels and such high pressures that damage to the motor happens really easily if there's a blockage."

DPA Diesel has invested in both training and equipment to service the latest common rail and injection units. One look at their spotless workshop will give you an indication of the dramatic change the diesel engine servicing industry has gone through. No more the old diesel grease pit here, but rather a diesel hospital where 'open-heart surgery' is performed on clogged 'aortas'.
   

The cliff-hanger?
It is just a matter of time before South Africa's diesel synchronises with imported diesel engines. Legislation for emission control is being promulgated and will force diesel producers and fleet operators to play enviro-friendly ball. In the interim, truckers must take preventative measures (filtering, additives and servicing) to ensure they keep their vehicles on the road.

And yes, there is a cliff-hanger to this story - it's making its way to a pump near you...It's a 'green' alternative to fossil fuels and it's called biodiesel...(watch this space).