The US Environmental Protection Agency is demanding the trucking industry reduce its emissions by 90% in 2007. It’s no small feat, and in order to comply, manufacturers will have to introduce new components as well as a costly aftertreatment system. Between now and December, Truck News will be exploring, in detail, each element of the 2007 emissions equation. We continue the series this month with Part 2 – a look at ultra low-sulfur diesel fuel.
TORONTO, Ont. – Sixty 2007 highway tractors will collectively emit the same amount of particulate matter as just one 1998 model truck. It’s a remarkable fact made possible by a variety of technologies, including a new type of diesel fuel that contains far less sulfur than the go-juice you’re used to putting in your fuel tank.
Ultra low-sulfur diesel is required for use with 2007 tractors. Its sulfur level is just 15 parts per million (PPM) compared to 500 PPM which was the industry norm until June. Sulfur must be reduced to avoid premature clogging of the diesel particulate filter (DPF) – a trap that collects and then burns off particulate matter at high temperatures.
Refineries in Canada and the US have been upgraded to produce ULSD and the new fuel began making its way to truck stops in June. By Oct. 15, 80% of diesel fuel sold in the US must be ULSD. In Canada, it will be closer to 100% says Andy Pickard, a fuel expert with Petro-Canada.
“In Canada, all on-road diesel must be ULSD as of Oct. 15,” he says. “Drivers won’t have a choice in Canada.”
High-sulfur diesel fuel will still be available as home heating fuel and for off-road applications in some parts of the country – mostly in the east. However, all diesel pumps will be required to display a label indicating the type of fuel it is dispensing. Here in Canada, the label will be yellow while in the US it will be green.
Having just one type of fuel widely available in Canada could be a blessing, Pickard says. It reduces the risk of misfueling, which can damage the DPF.
“High sulfur 500 PPM fuel will be potentially harmful because it will result in premature filter plugging by sulfates much more quickly than 15 PPM ULSD,” points out Alex Drohomyrecky, retail product quality advisor with Shell Canada.
When the DPF becomes clogged, it causes a loss of power and decrease in fuel mileage. The filter has to be removed from the truck to be cleaned. It’s a time consuming and somewhat onerous process that won’t be required any more than once for every 200,000-400,000 miles – if the proper fuel is used.
Dan Arcy, technical marketing manager with Shell, adds “For the 2007 engines, it is critical you use ULSD. Just one tank will cause the engine not to operate properly and it could impact the warranty of that engine.”
Drivers who operate in the US will have to be cautious when filling up their trucks. With 20% of diesel sold in the US still containing 500 PPM of sulfur, the potential for misfueling is far greater than it will be in Canada. A green sticker will be placed on US pumps indicating the type of fuel it dispenses, but read carefully – 500 PPM fuel is referred to as “low sulfur diesel,” not to be confused with ultra low-sulfur diesel.
“The nozzle is not changing so it’s critical to instruct drivers to make sure at the pump,” Arcy says.
While refiners have been shipping ULSD since June, it may not yet be at 15 PPM when it enters your engine.
Charlie Lund, quality assurance specialist with Imperial Oil, points out fuel in Canada will be under 22 PPM by Sept. 1 and finally at 15 PPM by Oct. 15. While the fuel is being produced at levels as low as 8 PPM at the refinery, contamination can occur at each handoff point along the supply chain, bringing the sulfur level up to in excess of 15 PPM by the time it reaches the truck stop. Also, service stations have to cycle through a few tanks of ULSD before the leftover 500 PPM fuel in the tank is entirely removed.
Under normal driving conditions, most drivers won’t notice any difference in performance when running ULSD, Lund says.
“We would anticipate that drivers will not notice any change, there are no concerns there,” he tells Truck News.
However, Ralph Cherrilo, distillate fuels advisor with Shell Global Solutions, says drivers may notice a slight decrease in power when operating at peak torque with heavy loads. ULSD has slightly less energy content, which may result in a slight fuel economy degradation.
“The hydrotreating process involved in the removal of sulfur reduces density and therefore energy content,” says Drohomyrecky. “The driver will likely notice a 1-2% reduction in fuel economy.”
Imperial Oil’s Lund points out there has always been a significant variance in the energy content of diesel sold in Canada due to weather and other variables, so the driver may not notice the change at all.
Another area impacted by the removal of sulfur is the lubricity of the fuel. Producers must adhere to strict lubricity standards, however, so additives will be injected into the fuel at the refineries to ensure there is adequate lubricity.
All producers advise against using aftermarket lubricity additives.
“No additional ‘driver-added’ lubricity agents will be required,” Drohomyrecky insists.
“In Canada, there’s a good lubricity requirement that does protect the fuel pumps,” says Petro-Canada’s Pickard, noting the standards for lubricity are more stringent in Canada than in the US. “With additives, there’s always the danger of adding too much and causing negative side effects. Lots of people think that if some is supposed to be good, more is better and that’s not the case. Some can cause detrimental effects if poured in too high a concentration.”
Truckers using older equipment – particularly trucks built prior to 1993 – should keep a close eye on seals to ensure no problems arise, advises Cherrilo. He says the fuel system elastomers were made of synthetic compounds beginning in 1993, which should ensure compatibility with ULSD. In older, high mileage engines, however, he suggests “customers should pay attention and do some preventive maintenance and then they won’t have any problems.”
Chevron officials say testing has shown very few vehicles experience fuel system leaks when transitioning to ULSD and only a small fraction of vehicles will be impacted.
ULSD will meet the same cold weather operability requirements and cloud point schedules as 500 PPM fuel, so no performance deterioration is expected in cold weather, says Shell Canada’s Drohomyrecky. But there are concerns south of the border about the availability of ultra low-sulfur kerosene, which is used to winterize the diesel.
While none of the producers are keen on discussing the price of ULSD (“the market will dictate the price,” is the common response) it’s expected to cost about 2-3 cents per gallon more than today’s fuel.
“The processes and tight tolerances needed to produce ULSD also result in further increases in refinery operating and maintenance costs,” Drohomyrecky points out. “These factors raise the manufacturing cost to refiners and suppliers of ULSD. Capital investments have also been made by pipelines, terminals, tank truck carriers and other parties throughout the distribution system. Refiners will expect to recover the cost of investment.”
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