Tesoro Corp. (TSO) started a hydrotreater at its Los Angeles refinery after maintenance, according to a person familiar with plant operations.
The hydrotreater began a return to service this weekend, said the person, who declined to be identified because the information isn’t public.
Tina Barbee, a spokeswoman at the refinery, didn’t immediately return an e-mail requesting comment.
A hydrotreater removes sulfur, metal and other impurities from refined oil products, allowing them to burn more cleanly as fuels.
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