ConocoPhillips has purchased a 50 percent stake in a $5.2-billion crude oil pipeline that will link the Wood River refinery in Roxana with an oil-producing region in northwest Canada.

Houston-based ConocoPhillips, the nation’s second-largest refiner, committed in November 2005 to ship oil on TransCanada Inc.’s Keystone pipeline — an agreement that also gave the company the right to buy a 50 percent interest.

The pipeline will “play a significant role in integrating ConocoPhillips’ upstream and downstream assets and ensure market access for growing Canadian production,” Chief Executive Jim Mulva said in a statement.

The 2,100-mile pipeline will be able to deliver 590,000 barrels of oil a day from Hardisty, Alberta, to Wood River and oil terminals in Patoka, Illinois and Cushing, Oklahoma. Oil shipments will begin in late 2009, Calgary-based TransCanada said.