Multicomponent mixtures cracking

Product separation for main fractionators is also often called black oil separation. Main fractionators are typically used for such operations as preflash separation, atmospheric crude, gas oil crude, vacuum preflash crude, vacuum crude, visbreaking, coking, and fluid catalytic cracking. In all these services the object is to recover clean, boiling range components from a black multicomponent mixture. But main fractionators are also used in hydrocracker downstream processing. This operation has a clean feed. Nevertheless, whenever you hear the term black oil, understand that what is really meant is main fractionator processing. 

Allen, D. T., Structural models of catalytic cracking chemistry. In Kinetic and Thermodynamic Lumping of Multicomponent Mixtures (G. Astarita and R. I. Sandler, eds.). Elsevier, Amsterdam, 1991, p. 163. 

H Briesen, W Marquardt. Adaptive Model Reduction and Simulation of Thermal Cracking of Multicomponent Hydrocarbon Mixtures. J. Comput. Chem. Eng. 24, 1287-1292,2000. 

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