REFINERY MARGIN TRACKER: USGC, USWC refinery margins strengthen ahead of OPEC + pact By admin Posted July 19, 2021 In In the News REFINERY MARGIN TRACKER: USGC, USWC refinery margins strengthen ahead of OPEC + pact2021-07-192021-07-19/wp-content/uploads/liberty-petroleum-icon-logo2.pngLiberty Petroleum Corp/wp-content/uploads/liberty-petroleum-icon-logo2.png200px200px US refinery margins for the week ended July 16 rose despite higher crude prices, trumped…