Guest Columnist: Melanie Collison
The “new” oil
(Oilweek Magazine, March, 2009)
It has been amazing to watch the ascendance of water as the subject around which everything else of import circulates. Five years ago, saying the scarcity of water in southern Alberta could emerge as the potential limit to growth was met mostly with scornful responses. These days, the whole province is paying attention to preserving the supply of fresh water, and oil and gas companies are foremost among concerned stakeholders, along with government and researchers.
While water has long been used to enhance production from mature conventional oil reservoirs, there´s no question that the effective management of water is also central to unlocking the future of the oil sands industry. The focus on water has come about as the result of a confluence of pressures. In no special order: projects organized by the Petroleum Technology Alliance Canada (PTAC) during its formative years; the provincial government´s Water for Life policy; the ripples of concern spreading among the public in response to very vocal criticism of water policies and industrial fresh water use voiced by David Schindler at the University of Alberta and Mary Griffiths at the Pembina Institute, among others.
Certainly within the industry there are leaders who insist on continuous improvement of processes to spare fresh water. Browse through canadasoilsands.ca, for instance, and you´ll see blog entries by Rick George, chief executive officer for Suncor Energy, and Imperial Oil Ltd.´s chief executive officer Bruce March. The website is a discussion forum set up by oilsands producers to hear Canadians´ concerns about the industry and its impacts. George writes: “In terms of water, Suncor has reduced its absolute water use by 40 per cent in the past five years. Ninety per cent of water used to generate steam at our in situ operations is recycled. And with our current [now delayed] expansion plans, we have requested a zero per cent increase in our license to withdraw water from the Athabasca River.”
March adds: “Syncrude Canada, which began production in 1978, has greatly improved its water-use efficiency. The Syncrude plant now uses 60 per cent less water for each barrel of oil produced than it did in the 1980s. Today, water extracted from the river is reused and recycled 18 times. “For in situ oilsands facilities,” March continues, “we´ve had great success in reducing our water use. Here, water is used to create steam, which is injected underground to heat bitumen, allowing it to flow to the surface through wells.
In 2007, Imperial Oil´s Cold Lake operations used 85 per cent less fresh water per unit of production than in the mid-1980s. We achieved this by recycling more than 95 per cent of the water produced with bitumen. “In addition, since 1993, saline groundwater not suitable for human or agricultural use has been pumped from deep aquifers to use in place of fresh water. Our industry partners have also kept pace,” he is quick to add. “Canadian Natural Resource Limited´s Primrose operation also uses saline water to produce bitumen. Other companies such as Petro-Canada, Opti-Nexen, Devon Energy, and ConocoPhillips have also recently developed oil sands in situ operations that use saline water and have high water recycle rates.”
Similarly, water is of concern to conventional oil and gas producers not only from the perspective of avoiding fresh water use but because the burden of handling and disposing of produced water is so expensive. As PTAC director of increased recovery Bruce Peachey says, “All oil and gas operations have to deal with water issues from exploration to abandonment.” We´re in the water business every bit as much as we´re in the oil business, as the saying goes.
Just how prominent water has become is evidenced by the sparkling new Water and Environmental Science Research Facility at the University of Lethbridge, a long-time sector leader with its host of veteran researchers. Innovative in its interdisciplinary approach, the $27-million facility pulls together numerous provincial and federal water research partners, including the Alberta Ingenuity Centre for Water Research. At the official opening in November, Stewart Rood, professor of biological sciences, pointed out that while all living things rely on water, less than one-half of one per cent of the water on earth is accessible, liquid, and fresh. It´s not news, but it´s still shocking, and it gives impetus to investigations at the intersection of industry and academia.
Nexen Inc. is funding a Fellowship for Water Research at the new Lethbridge centre. In announcing it, former chief executive officer Charlie Fischer said, “The availability, quality, and conservation of water are key issues for the petroleum industry and there is growing competition among industry, agriculture, and municipalities for access to both surface and groundwater.”
In timely fashion, a University of Calgary researcher, Maen Husein, has been doing work that promises to transform that competition into cooperation. Husein is an assistant professor in the department of chemical and petroleum engineering at the Schulich School of Engineering. Husein and his research team are developing new ways to clean up produced water to such a purity that it can be used in oil and gas operations or used for irrigation. That requires removing organic contaminants. His laboratory is also running projects on removing heavy metals from industrial waste water. “We´re trying to test ultrafiltration as an option of treating produced water, which contains organic material and suspended solids because of its contact with the oil,” Husein recently told Oilweek. “Our objective is to use it for irrigation at least, if not recycle it back into oil processing.”
The standard of purity for oil production processes is higher than it is for irrigation because salts and silicon in water cause corrosion problems in metal equipment such as steam boilers. If Husein can find the industry backers he needs to take his bench-scale successes to pilot project scale, he might just solve enormous headaches for two industries that haven´t always been the best of friends. “Most of the [fresh] water we use in Alberta is for irrigation,” Husein says. “At the same time] huge volumes of produced water are currently injected into wells, wasted. We´re not making use of it.” The technique under examination is a means of enhancing ultrafiltration of non-potable water. On the spectrum of filtration membrane pore size, ultrafiltration sits midway between the larger ordinary ceramic filtration membranes and tiny nano-scale filtration.
Ordinary filtration flows at an acceptable rate for the economics of water treatment but it lets organic contaminants through, so the quality of water is definitely not adequate for oil processing. Nanofiltration results in significantly more pure water, but requires pressure to achieve acceptable flow rates. That application of pressure consumes energy, which adds cost. Ultrafiltration without enhancements can handle economic rates of flow; however, it doesn´t remove enough contaminants to meet the specifications for boiler feed water. To purify produced water without triggering the cost of using pressure, Husein´s research team is enhancing the filtering process by adding a surfactant-a surface-active agent or detergent. A surfactant makes organic matter soluble in water and causes the molecules to clump together in an orderly fashion in roughly spherical formations. These spheres, called micelles, are too big to go through an ultrafilter, hence the name of his project: “micellar-enhanced ultrafiltration.” “These micelles enlarge or make the size of the contaminant bigger so it´s retained by the ultrafiltration pores,” Husein says. “It [has been] done in the past on model materials, for example, benzoic acid, to remove it from synthetic contaminated water. “We decided to apply [the concept] to real produced water samples. We thought there would be a synergistic effect, that the contaminants would improve the structure of the micelle and make it bigger so we would need to use less surfactant. It worked perfectly in the lab, and we have published a couple of papers on the topic. Nobody had [previously] thought of this educated guess.” The team had tried to duplicate another centre´s earlier work that caused contaminants existing in the water to function as surfactants. They were unable to achieve success following the same steps of removing hydrogen molecules and adding sodium, so they experimented with adding the small amount of surfactant. The filtration membrane is a polymeric and ceramic membrane composed of metal oxides that are packed together in a porous structure. “The pores have to be uniform and controlled,” Husein says.
Advanced hollow fibre membrane technology for water and waste water treatment was pioneered by Zenon Environmental Inc., headquartered in Ontario. In 2006, Zenon was bought by GE Water and Process Technologies, a unit of General Electric Company, to pump up its water treatment business. “We used a bench-scale model [of membrane], 20 centimetres long and about 5 centimetres in diameter,” Husein says, “but in an industrial application, the [filter] can be 2 metres long and 30 centimetres in diameter [external measure]. You then have a unit that contains all these ceramic membranes together, with one entrance flow and one exit flow.”
Given the rising tide of concern about water, Husein has his sights set on finding an industry partner by summer to scale up his work, once the economy settles a little. In fact, the economy´s problems might give him a boost as society refocuses its attention on doing more with less, and in particular, on new ways to avoid waste of any kind. As University of Lethbridge president Bill Cade said at the opening of the new research facility, “Everywhere in the
world has a water crisis taking place now…. Water is probably the most important commodity in our lives, aside from our human potential and our brains.”
Reprinted from an article published in “Oilweek Magazine” March, 2009.