Saturday, February 22, 2014

Cosignatory

 Roger Butler wasn’t alone: one of the other two names on the SAGD patent muses on the origins of the game-changing technology; this article appears in the March issue of Oilsands Review
By Peter McKenzie-Brown
You can become a pioneer at any age.Take the case of Bruce Slevinsky, who was born in Edmonton in 1950. Atage 28, he was one of three signatories on the original patent for steam assisted gravity drainage (SAGD). The others were Roger Butler (1927-2005) and Chic Bombardieri (1920-2012).

When interviewed for the Oil Sands Oral History Project, Slevinsky contributed his copy of that legendary patent to the archives of the Calgary-based Glenbow Museum. Butler—whom Slevinsky describes as “very jovial, but very, very driven”—is the best known among those who patented SAGD, and he is often given sole credit for the idea. Indeed, as a researcher at Imperial Oil Limited’s Sarnia, Ont., research centre, in 1969 he had developed a SAGD-like process to extract potash from an underground ore body.

“The way he explained it to me is that [the idea] came from the old coffee percolators,” Slevinsky says. “You’d put energy in the bottom, it percolated steam and water to the top, it all condensed at the top, and then the water drained through the basket of coffee, and then you produced the coffee out the bottom.” This idea ultimately led to “thermal melting of crude and gravity drainage”—the key ingredients in SAGD.

Butler continued working on heavy oil extraction as an extension of his potash mining expertise, getting his first vertical well patent in 1969. Slevinsky says he lobbied hard to get transferred to Calgary because he had a vision that he could transform the Cold Lake cyclic steam stimulation (CSS) project, which had yet to turn a profit.“They were working full tilt to optimize CSS, so it became a head-to-head battle when Roger finally arrived in Calgary.”

In the Calgary lab, Slevinsky was focused on the Cold Lake pilots. He did “work on deviated wells, multiple fractures, injectivity analysis for the steam injectors, the formation of emulsions in the huff-and-puff process—all based on the fracture mechanics at the heart of my PhD work.” A year later, Butler arrived, and “the lab went into overdrive researching the fundamentals of the SAGD. “Within the first six months or so that Roger was in Calgary,” Slevinsky says, he and his colleagues “proved that Butler’s vertical well concept wouldn’t work. Economically it could not compete with what was happening with cyclic steam on the vertical and deviated wells at [Cold Lake].”

Regrouping, they asked, “How could we get higher rates?” That’s when they came up with the idea of using horizontal wells—but horizontal drilling was not a commercial technology. While Slevinsky moved on to work on the Syncrude Canada Ltd. mine and Imperial’s conventional oil and gas projects—including leading a proposed CO2 miscible flood at Judy Creek, Alta.—the technology behind SAGD continued to develop through the efforts of Butler and his students at the University of Calgary.

In the early 1990s, testing at the Alberta Oil Sands Technology and Research Authority Underground Test Facility (UTF) proved the SAGD concept. At the same time, horizontal drilling had also achieved  commerciality, and interest in SAGD began to grow. Including for Slevinsky’s employer, which, after a stint away from Imperial doing consulting work, was now Petro-Canada.

With Petro-Canada he had circled back to SAGD, both in theory and in geography—the leases where the company was planning to develop its MacKay River SAGD project were adjacent to the UTF site. “I brought reservoir characterization and modelling processes and concepts to the company and helped the engineers there on many projects.” Among those, he developed the first geostatistical model for the MacKay
River SAGD project.

MacKay River became the second commercial SAGD project when it commenced operations in 2002. For the past several years, the project has been a performance leader in production.
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