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+ By Pierre Home-Douglas
COVER STORY
Heavy Industry - Can Canada enjoy both an oil-sands boom and a clean environment? At the University of Alberta, more than 1,000 researchers are trying to find out. By Pierre Home-Douglas
A Caterpillar 797 truck, capable of hauling 400 tons, helps make oil-sands extraction possible on a large scale. But it also adds to the process’s greenhouse gas emissions.

Canada has a problem most countries would envy. Vast oil deposits cover an area bigger than Florida and contain an estimated 175 billion barrels of bituminous crude, making the province of Alberta home to one of the richest reserves on the planet, just behind Saudi Arabia and Venezuela. Time magazine calls it “Canada’s great buried energy treasure.”

Trouble is, that molasses-like treasure lies locked in tar sands. Extracting it has meant cutting into ancient boreal forests, storage of vast amounts of polluted wastewater, and production methods that critics say release three times as much greenhouse gas as conventional oil drilling. The Natural Resources Defense Council calls it “the world’s dirtiest oil.” Plans to pump the crude via the Keystone XL pipeline through the American heartland to Texas have ignited a fierce political battle between the Obama administration, which is blocking the pipeline, and congressional Republicans, who have made it a defining election-year issue. Canada’s government, meanwhile, has put its cooperation in the fight against global climate change on the line, opting to withdraw from the Kyoto Protocol rather than make the required cuts in emissions.

© PRNewsFoto/General Dynamics Bath Iron Works
Strip mining is cutting away parts of Alberta’s vast forests. © Peter Essick / Aurora Photos

Far from the noisy debates in Washington and Ottawa, a small army of engineers at the University of Alberta is pursuing what all sides would likely consider a worthwhile goal: make the manufacturing process more efficient, with both breakthrough technology and incremental daily improvements. So far, the efforts have resulted in innovations in areas from oil-extraction techniques to waste mitigation, helping the industry raise output, save energy, and cut both costs and the amount of greenhouse gas emitted per barrel.

Humans have been recovering bitumen from oil sands since paleolithic times for uses ranging from mummy preparation to adhesives to waterproofing. But liberating this extremely viscous form of petroleum on a large scale, when much of it is buried 75 meters or more deep, poses unique engineering challenges. “You shouldn’t think of the oil sands as a hydrocarbon fossil-fuel conventional industry, where you drill and recover and send it off to a pipeline,” cautions David Lynch, dean of engineering and a leading expert on oil-sands processing. True, the oil starts in the ground and gets distributed via pipeline. But “everything else in between is different.”

Extracting bitumen from oil sands - This is the method for deposits close to the surface. Deep deposits require drilling and Steam Assisted Gravity Drainage.
Courtesy Suncor Energy Inc.

Public-private research

For deposits fairly close to the surface, the top “overburden” stratum of soil, rock, and other materials is stripped away and giant shovels scoop up 100 tons of oil sands at a time and dump their load into trucks. Hot water is added to soften the bitumen, and the mixture is transported by pipelines to a facility for extraction and eventual upgrading before the oil can be refined. About 80 percent of Alberta’s oil-sands reserves are too deep to mine economically, however. So scientists and engineers have developed a method known as Steam Assisted Gravity Drainage. In this process, two parallel horizontal pipes are drilled into reservoirs hundreds of feet underground. Steam injected into one pipe heats the bitumen enough to flow into the lower horizontal pipe and up to the surface.

Improving the whole operation has galvanized U. of A.’s faculty of engineering, where no fewer than 1,000 professors and graduate students are working on it full time. That kind of capacity “didn’t happen randomly,” notes Lynch. Over the past two decades, he says, public-private partnerships have provided research opportunities and matching grants to hire faculty “who can do fundamental work but also possess a background and have interests that could mesh with needs of the oil sands industry.” If industry puts up $1 million over five years, for instance, Canada’s Natural Sciences and Engineering Research Council (NSERC) will contribute the same, with the provincial government often kicking in funds as well. The researchers are building on nearly a century of pioneering oil-sands work. In the 1920s and ’30s, Karl Clark, chair of mining and metallurgy, developed a hot-water extraction process that, with modifications, is still used today to mine oil sands close to the surface. The first full-scale commercial operation didn’t start until 1967, however, and it took the Great Canadian Oil Sands company 11 years more to bring a second plant online. Why the delay? As Lynch explains, in the 1980s “oil was down at $10 a barrel while production costs were $30 a barrel — not a great economic proposition.” A decade later, the company seriously considered shutting down part of the operation. Only after oil prices vaulted in the early ’90s was Lynch able to persuade key oil-sands companies that universities could contribute to the profitability, efficiency, and environmental effectiveness of their operations. The first industrially funded research chair in oil-sands engineering was created in 1995, and “we started to grow one program after another,” Lynch recalls. Last year, the university added six NSERC-endowed chairs.

Mining shovels scoop up oil sands 100 tons at a time and load the material onto 240- to 380-ton trucks.
Mining shovels scoop up oil sands 100 tons at a time and load the material onto 240- to 380-ton trucks. Courtesy Suncor Energy Inc.

Many major oil-sands manufacturing innovations have benefited from U. of A. engineering expertise. Consider the introduction of hydrotransport, a process developed in the early 1990s by researchers from Syncrude Canada, a leading producer of bituminous crude from oil sands that has raised efficiency and reduced pollution. At the time, oil sands were moved by conveyor belts from mine to processing plant, where giant, cement-mixer-like tumblers would help begin the oil separation process. Syncrude researchers discovered that adding hot water to the oil sands allowed more efficient transmission by pipeline. By the time the oil sands reached the extraction facility, most of the oil already had separated from the sand and clay in transit. “Basically, you got two jobs done for the price of one,” explains Sean Sanders, associate professor of chemical and materials engineering at the University of Alberta, who holds the NSERC Industrial Research Chair in Pipeline Transport Processes. “You get the material being moved from the mine to the extraction [plant], and at the same time the oil sands are being prepared so they can properly be separated.”

U. of A. engineering educators helped hone the idea. Initially, the extraction process used water heated to 175 degrees Fahrenheit. Jacob Masliyah, professor emeritus of chemical engineering, demonstrated that the temperature could be reduced without any decrease in effectiveness. The less energy needed to heat the water, the lower the carbon dioxide emissions. “It was all done using fundamental scientific principles and techniques,” Masliyah recalls. Using “very sophisticated instrumentation,” his research team was able to show a sharp reduction in adhesion force between bitumen — the tarlike oil — and sand when processed with water at 95 degrees. “The industry can now comfortably operate its processes at a temperature of just above 102 degrees Fahrenheit,” says Masliyah. For his work in the oil-sands industry, the Baghdad native was elected a member of the U.S. National Academy of Engineering in 2011.

Location of the oil sands in Canada
Location of the oil sands in Canada

Inside the pipeline

Today, fellow engineering professor Sean Sanders is working to further boost the efficiency of hydrotransport. He wants the oil-sands industry “to see the pipeline as a reactor” where conditions can be changed to improve bitumen extraction. “For 20 years, people in industry have said, ‘Once it’s in the pipeline, what can you do?’” explains Sanders. “But if you know what’s happening in there, you can know exactly when to add air, or a process additive, or vary the mixing intensity, or something that will help make the process more efficient.”

Another challenge Sanders hopes to conquer: changing mining methods to reduce or eliminate the use of monster trucks, a huge source of carbon dioxide emissions. Each Caterpillar 797 used to transport oil sands from strip mine to processing plant can carry close to 400 tons on its 13-foot wheels. The trucks also produce roughly 25 percent of the carbon dioxide emitted by oil-sands operations.

Mining shovels scoop up oil sands 100 tons at a time and load the material onto 240- to 380-ton trucks.
Hydrotransport pipelines at the Suncor oil-sands plant. Courtesy Suncor Energy Inc.

Eliminating trucks goes in lock step with what Sanders calls remote extraction, or “designing a mobile preparation facility that would follow the shovels around.” Currently, hydrotransport pipelines are 1 to 3 miles long. Shorter, more mobile pipes would reduce that distance to less than 600 yards. Sanders hopes to develop a rapid-conditioning process that is “robust enough to work on all kinds of ore,” which can vary widely in quality even within a few hundred yards at one mine site.

Further efficiencies are being sought on the receiving end of the hydrotransport lines, where oil is separated from dirt in huge reservoirs known as primary separation cells. Five stories high and 70 feet in diameter, one such tank at the Suncor plant processes 50,000 barrels of oil a day from the slurry of oil, sand, and clay that comes in. Plant operators face a problem, however. Pumps suck out water and sand from the bottom of the tank, leaving a middle layer of clay, water, and oil. The crude floats to the top where it is skimmed off, but the mixture underneath constantly shifts. Any oil sucked into the exit pumps ends up in tailings ponds, meaning lost revenue and more pollution. But adjusting the speed of the pumps is part art, part science. Enter chemical and materials engineering professor Sirish Shah and doctoral student Phanindra Jampana. The pair designed an image-based sensor that used sophisticated algorithms and a digital camera aimed through a viewing window into the tank to analyze 10 video clips per second and adjust the pumps. The result was a 50 percent reduction in the inadvertent flow of bitumen into tailings ponds — about 1,600 barrels of added oil production per tank. Shah and Jampana won a 2011 award from the Alberta Science and Technology Leadership Foundation for their work.

The path to oil-sands innovation also includes setbacks. Before Shah’s work, for example, the industry had spent several million dollars on techniques that proved unreliable and ineffective, such as using gamma radiation to pinpoint the interface level, notes David Lynch, the engineering dean.

A $3 million fine

One of the most vexing oil-sands engineering problems over the past 45 years has been what to do with wastewater and sludge. It takes at least two barrels of water to extract a single barrel of oil. That oil-tainted water cannot be returned directly to its source, the Athabasca River and its tributaries, so it ends up in huge holding ponds. The water can be treated and recycled. The sand settles to the bottom. Much of the clay, however, forms a relatively stable suspension with 15 percent solids and the consistency of yogurt. These “mature fine tailings” (MFT) will not settle and thus cannot be dredged. So they accumulate in ever expanding tailings ponds — 65 square miles’ worth and counting. “The first barrel of MFT from 1967 is essentially still with us,” says Lynch. That alarms environmentalists, who point to a 2008 accident in which 1,600 ducks died after landing in a toxic pond. The company, Syncrude, had to pay a $3 million penalty, one of the largest fines for an environmental offense in Canada’s history. Beneficiaries included a University of Alberta bird migration project and the Alberta Conservation Association.

Engineers are exploring ways to shrink the tailings ponds. One method under evaluation involves spreading the clays in thin layers to promote evaporation. Researchers also see promise in the use of large centrifuges that can wring water from the tailings like a washing machine. Other methods being studied include adding a polymer to help suspended particles coagulate into a denser mass and expel water, making the sludge easier to handle, and recombining the MFT with sand. The tailings would bind with the sand’s microscopic holes to create a weightier material that would settle more swiftly to the bottom of the holding pond. “The science is well known, but the application of the technology is difficult,” says Jacob Masliyah. “It’s like having a drug that will cure you of a disease, but how do we administer that drug effectively?” Fellow engineering professor Ward Wilson adds, half-jokingly: “We could make vineyards and ski hills if you want; it’s all a matter of cost. What gives you the best physical performance at what cost?”

One solution to the water problem is not to use it in the first place. The Center for Oil Sands Innovation (COSI), a U. of A. research facility set up in 2005 to find breakthrough technologies for oil-sands production and upgrading, is investigating nonaqueous extraction. (“Only engineers could find their heart beating faster at the mention of ‘nonaqueous extraction,’” jokes David Lynch.) The mission has some urgency. “People have been focused on the problem of tailings for a long time, and so far there is no really satisfactory answer,” says COSI scientific director Murray Gray. “Our approach is to step outside of that box and ask: What are completely different approaches that may have merit?” His team is experimenting with solvents and other additives to remove the oil from the tar sands without leaving behind highly concentrated residue and creating an even bigger environmental problem. If successful, he says, the remaining mixture of sand grains and clay particles could be easily handled as a dry powder and returned to the mine site for speedier reclamation. “You don’t have to build these huge ponds to hold sludge for decades,” explains Gray. “It completely changes everything.”

COSI also has focused on upgrading the oil — processing extracted oil so it has more value for the refinery. Currently, upgrading requires high temperatures generated by furnaces and the addition of hydrogen gas. Both increase air pollution. COSI researchers are examining ways to reduce operating temperatures, pressures, and the amount of hydrogen needed. “Basically, how to do it cheaper, better, and with less energy consumption and less carbon dioxide production,” sums up Gray.

Canada’s research engineers seem confident of designing more efficient systems to wring every possible drop of liquid treasure from Alberta’s vast tar sands. Less certain is their ability to make oil-sands extraction clean enough to win acceptance on both sides of the U.S.-Canada border.


Pierre Home-Douglas is a freelance writer based in Montreal.

 

A Medical Side Benefit

Oil-sands technology has led to some serendipitous spinoffs. Take the optical work that University of Alberta engineering professor Sirish Shah and doctoral student Phanindra Jampana pioneered as a way to improve the extraction process in primary separation cells. The work caught the eye of physician Patrick E. Duffy at the National Institute of Allergy and Infectious Diseases in Washington, D.C.
Or rather, it caught his ear.

Duffy met Shah at a wedding reception in Oregon. The two started talking about their careers, and when Shah mentioned his imaging work, Duffy started thinking about how it might be applied to his field of expertise: malaria detection. According to the World Health Organization, malaria kills nearly a million people worldwide every year. Manual microscopy used to be the gold standard for diagnosing malaria; an operator would examine blood-smear slides and count the number of red blood cells infected by parasites. This time-consuming diagnostic method is prone to human error, however, even in experienced hands. With the help of graduate student Yashasvi Purwar, Shah came up with a way to eliminate inconsistent results using the digital-imaging process he developed to improve oil-sands yield. After three years of testing and fine-tuning the technique, they arrived at a faster and more cost-effective way to detect infection. Shah published the results of “automated and unsupervised detection of malarial parasites” in the December 2011 issue of Malaria Journal. “It’s truly amazing to realize the breadth of applications of imaging analysis and systems,” Shah says.


 



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