UPDATE 1-Valero may run refineries at 78 percent in Q3

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HOUSTON, July 28 (Reuters)- Leading U.S. refiner Valero Energy Corp (VLO.N) said on Tuesday its 16 refineries may run at 78 percent of capacity in the third quarter of 2009.

The company's main refining hub on the Gulf Coast will run between 1.2 million and 1.25 million barrels per day (bpd) in the third quarter of 2009, 75 percent of the total 1.6-million bpd capacity.

Valero expects total throughput at all of its refineries to run between 2.33 and 2.41 million bpd in the third quarter, down from a total capacity of 2.99 million bpd.

The biggest hit to Gulf Coast throughputs comes from the shutdown of Valero's 235,000 bpd Aruba refinery due to poor refining margins.

The shutdown began in mid-July and is expected to remain closed into September, when the company will review refining margins before restarting the plant, the company said.

Mid-Continent refineries are expected to run between 360,000 and 370,000 bpd in the third quarter down from total capacity of 455,000 bpd.

In the Northeast, Valero expects throughput to be between 500,000 and 510,000 bpd for the refineries that have a combined capacity of 630,000 bpd capacity.

West Coast refineries are expected to run between 270,000 and 280,000 bpd compared with a total capacity of 305,000 bpd. (Reporting by Erwin Seba; Editing by Marguerita Choy)