1、 https:/crsreports.congress.gov November 18, 2016Petroleum Coke: Industry, Health, and Environmental IssuesNorth American crude oil and natural gas production has increased significantly over the past decade, primarily as a result of new or improved technologies (e.g., hydraulic fracturing, directio
2、nal drilling, in situ injection) used on unconventional resources (e.g., shale, tight sands, coalbed methane, oil sands). The increase in production has occasioned a range of societal transformations, both economic and otherwise, including the potential for new environmental impacts. One area of con
3、cern arises from the production and use of petroleum coke, or petcoke. Petcoke is a co-product of several processes used during petroleum refining to upgrade “residuum” into gasoline and middle distillate-range fuels. Residuum (or resid) is the substance that remains after refineries initially disti
4、ll heavy crude oils. Nearly half of U.S. petroleum refineries (56 in 2015, as reported by the U.S. Energy Information Administration EIA) have the capacity to process heavy crude oils. Many refiners installed technologies over the past decade to take advantage of lower priced heavy crude oils from S
