For all the changes they're introducing, engine manufacturers seem to be breathing relatively easily. Equipment being designed to meet 2007 emission standards is performing well in test fleets, fuel e...
For all the changes they’re introducing, engine manufacturers seem to be breathing relatively easily. Equipment being designed to meet 2007 emission standards is performing well in test fleets, fuel economy has reportedly been maintained, and the gleaming stainless steel inside exhaust stacks offers visible proof that particulate matter is being trapped before it’s released into the atmosphere.
Indeed, the scenario is hardly a repeat of 2002, when engineers had to scramble to introduce largely un-tried technology such as Exhaust Gas Recirculation systems, seeing fuel economy drop in the process. Most companies are planning to meet the latest standards by tweaking existing combustion systems, and adding Diesel Particulate Filters to capture the tiny bits of particulate matter that could lodge itself deep in a person’s lungs. (Perhaps that’s the biggest reason to breathe a little easier. Respirable Particulate Matter is identified as a toxin under the Canadian Environmental Protection Act, and has been linked to health problems including cardiovascular disease.)
This time, it’s the refineries that have been saddled with one of the biggest challenges.
Sulfur levels in today’s on-road fuel can be as high as 500 parts per million, but by this fall refiners will need to sell Ultra Low Sulfur Diesel (ULSD) with levels as low as 15 ppm. Lower sulfur in the fuel will allow lower levels of ash in the oil that would otherwise foul Diesel Particulate Filters. And the lower levels of sulfur will even help reduce the damaging acids that have traditionally been created during the combustion process.
Like any scientific feat, however, this one is coming at a cost.
To guarantee 15 ppm sulfur in the fuel that you buy, refiners actually need to create fuel with levels as low as six or seven parts per million.
“We’re getting down to near-zero levels, and I think everyone is going to [experience] challenges distributing the fuel,” says Bruce McEwen, chief of Environment Canada’s fuels division. Some amount of sulfur will inevitably be picked up from the insides of pipelines, tanks, hoses, and the trucks used to transport the fuel.
And the chemical process comes with a real price. Members of the Canadian Petroleum Producers Institute (CPPI) have invested about $5 billion in the related equipment, equating to about 2-1/2 years of industry profits, says vice-president Dane Baily. “The investments are underway if not already completed.”
Ultimately, that translates into another two cents to produce every litre of diesel.
“Don’t confuse cost with price,” Baily adds hurriedly. “The market will determine whether we’re able to recover costs or we aren’t.”
But potential costs won’t be limited to those paid at a fuel island.
Sulfur is removed from fuel in a process known as hydrotreating, in which hydrogen is added to the mix to react with sulfur. But the hydrogen is sticky, and also clings to the chemical compounds that enhance a fuel’s lubricity, which protects fuel pumps and injection systems. Lower “aromatics” leave the fuel more prone to waxing in cold weather, plugging fuel filters and making cold-weather starts more difficult.
So far, it appears that today’s standards are being met with additives at the refinery level, but winter testing continues.
“The quality and consistency will be there. My confidence is high on that particular level,” insists Daniel Webster, International Truck and Engine’s Canadian sales manager. “The aromatics in the fuel, the cetane, the lubricity issues, we are assured by the CPPI that they will adhere to the existing [standards].”
MUCH ADO ABOUT NOTHING?
As crucial as the low-sulfur fuel is to protecting the diesel particulate filters, several engine manufacturers are quick to point out that small amounts of higher sulfur levels won’t be catastrophic.
“Non-approved fuels could cause damage or low-power complaints,” says Volvo Trucks spokesman Jim McNamara, referring to issues such as the plugging of filters that could cause higher back pressure in the exhaust system. At the very least, the higher levels of ash found in the filters will need to be burned off earlier than expected, consuming a little extra fuel in the process.
But the challenges are hardly an unknown. Volvo, for example, has been running engines on Scandinavia’s 10 ppm fuel since 1990.
Forget the suggestion of catastrophic failures, Webster adds. “While trying to clean out the pipeline and fuel suppliers, we might end up being 40 ppm, but it will not have the radical failure that people think it will.”
“One tank of fuel will not damage [the particulate filter],” agrees Steven DeSousa, Mack’s powertrain sales manager in Canada. “If you were to have subsequent tanks of 500 ppm or higher, you will plug [the filter] up prematurely, but we are going to have the infrastructure ready to clean it out.”
The ULSD can also be used in existing diesel engines with little impact, engine makers suggest. Any problems would probably be limited to the oldest engines in the fleet, particularly those with leaking seals. If aromatics are allowed to drop at all, seals that have shrunk with age may leak further still.
Early maintenance checks on this equipment should involve watching for pools of diesel under the vehicles, moisture at the bottom of engines, additional exhaust smoke, or an unusually strong smell of fuel when first starting the engine.
FUEL ECONOMY MAINTAINED
Donna McMahon, a senior fuels advisor with Petro Canada, says that ULSD will contain 1% to 1.5% less energy than today’s on-road diesel fuel, but engine makers feel they’ll be able to compensate with other improvements to their equipment.
Caterpillar has seen mid-range designs improve fuel economy by as much as 4%, adds Mark Kingsley, general manager of Caterpillar Canada. “It’s incredible when you see these engines operating 150,000 miles, and the exhaust stack is as clean as when it was new – shiny, stainless steel.”
Of course, the positive news would not have been possible without placing a number of test trucks in the field, and there was a behind-the-scenes scramble to ensure that fuel would be available for the tests. Most of the ULSD available in Canada was already being claimed by municipal fleets. The Canadian Trucking Alliance had to broker a meeting with engine makers, petroleum producers and Environment Canada to make it possible.
But there is a concern about fuel supplies in the US. While every drop of Canadian on-road diesel will comply with the 15 ppm limit once new engines are introduced, up to 20% of the US fuel supply will be allowed to contain up to 500 ppm of sulfur even after the deadline comes and goes. And the US Environmental Protection Agency has already needed to extend the deadline for selling the fuel. (It won’t be flowing through pumps until mid-October, whereas Canadian companies will be selling it by September.)
Refiners south of the border face an added burden. While the low sulfur levels require a $9-billion investment in technology, they’re still rebuilding infrastructure that was damaged by hurricanes Katrina and Rita. There are a finite number of experts who can conduct any of the work, says Charlie Drevna, director of policy and planning for the National Petrochemical and Refiners Association.
“Even before Katrina and Rita we, as an industry, had concerns about the potential supply impacts of this rule,” Drevna says. “With the devastation caused by those events, those concerns were exacerbated.”
Specifically, the US refiners have expressed concerns about the steps that need to be taken to push sulfur levels below 10 ppm.
“God didn’t create sulfur equally in crude,” Drevna explains, referring to three species that exist at the lowest levels. “Just a little bit of an upset can make a whole batch off spec’. There is no room for error … you’ve got contamination issues all the way down the line that [can] render those batches useless. And what are you going to do with
“It’s going to be a learning curve for everyone.”
Indeed, even Canadian refiners need to base their confidence in computer projections, Baily says. Just how much sulfur will actually be picked up every time the fuel is handled? Remember that each litre will need to travel through a complex supply chain including refinery, multiple terminals, rail cars, tanker trucks and the hoses that load it from one spot to another.
“You don’t know [for sure] until you actually try it,” he says.