UPDATE 1-Shell completes repairs at Scotford upgrader

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CALGARY, Alberta, Dec 31 (Reuters) - Royal Dutch Shell Plc (RDSa.L) completed repairs to its fire-damaged Scotford oil sands upgrader and is now producing in excess of half its 155,000 barrel per day capacity of synthetic oil, with full output expected next month.

Shell spokesman Randy Provencal said on Monday that repairs were complete on both production trains at the complex, including the one damaged in a Nov. 19 fire at the site near Edmonton, Alberta.

One residue hydroconversion unit is already at full output. The second, which was damaged in the fire, is beginning to be restarted, a process that will be complete in January.

"Production has resumed at the upgrader," Provencal said.

Shell's Muskeg River oil sands mine, which supplies tar-like bitumen to the upgrader, is also returning to production to provide feedstock for the facility.

Shell's 98,000 bpd Scotford refinery, which is tied into the upgrader, has been running at full output using synthetic crude purchased from outside suppliers. However Provencal said the company will replace purchased feedstock with the upgrader's production.

Shell owns a 60 percent stake in the upgrader and the Muskeg mine, with Chevron Corp (CVX.N) and Marathon Oil Corp (MRO.N) each holding a 20 percent share. Shell is the sole owner of the refinery. (Reporting by Scott Haggett; Editing by Rob Wilson)