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CALGARY, Alberta, June 16 (Reuters) - Imperial Oil Ltd , Canada's No. 2 integrated oil producer and refiner, said on Tuesday that production has begun at the second, C$9 billion ($7.3 billion), phase of its Kearl oil sands mine in northern Alberta, doubling the capacity of the site to 220,000 barrels per day.
The company, majority owned by Exxon Mobil Corp, said all three production units at the expansion are now operating, two years after the project's initial phase started up.
While the expansion project entered service about a month earlier than expected, the site is unlikely to produce at full capacity this year.
"We anticipated an early July start-up," Arthur Grayfer, an analyst at CIBC World Markets, said in a research note.
"We anticipate it will take about a year to reach capacity."
The expansion was the last major construction phase for the project. The company has said it expects to do further work on the existing facilities to push output up to 345,000 bpd by 2020.
Imperial shares were down 0.4 percent to C$47.17 on the Toronto Stock Exchange. ($1 = 1.2321 Canadian dollars) (Reporting by Scott Haggett in Calgary and Anannya Pramanick in Bengaluru)