ABSTRACT
In this chapter, complexity indices are used to classify and distinguish refineries, and the process flow diagrams from two cracking refineries are examined. Refineries consist of a series of interconnected and interdependent processing facilities. Simple refineries do not contain any conversion units and are variously referred to as topping, skimming, or hydroskimming plants. A topping refinery has no conversion or finishing processes, and its range of products is entirely dependent on the characteristics of the crude oil input. Conversion refineries also usually contain alkylation or polymerization units for converting olefin streams to gasoline and petrochemical blendstocks, and might contain an isomerization unit. Not all cracking refineries have cokers, but most coking refineries have catalytic crackers. The presence of cracking and coking units almost always indicates additional process technologies within the refinery for converting olefin streams to gasoline and petrochemical blendstocks, aromatics, asphalt plants, sulfur recovery, and hydrogen production.
