REFINERY MARGIN TRACKER: US refinery margins slip as Colonial Pipeline flows By admin Posted May 24, 2021 In In the News REFINERY MARGIN TRACKER: US refinery margins slip as Colonial Pipeline flows2021-05-242021-05-24/wp-content/uploads/liberty-petroleum-icon-logo2.pngLiberty Petroleum Corp/wp-content/uploads/liberty-petroleum-icon-logo2.png200px200px US refining margins slipped lower as the Colonial Pipeline returned to service after a May…