Thermal cracking kinetics of Kuwaiti vacuum residues in Eureka process

This work presents the development of a kinetic model for the thermal cracking of vacuum residues in a pilot-scale semi-batch reactor, which simulates the cracking operation performed in the Eureka process. The vacuum residues were derived from three Kuwaiti crude oils, both conventional and heavy. Experimental data was obtained at three cracking temperatures (400, 415, and 430 degrees C) and three reaction times (30, 50, and 60 min). The proposed thermal cracking kinetic model is based on the discrete lumping approach. The reaction scheme consisted of five lumps: the four cracked products and residual unconverted oil. The cracked products represent the product slates obtained from the commercial Eureka process, namely, the off-gases (<150 degrees C), cracked light oil (150-370 degrees C), cracked heavy oil (370-538 degrees C), and demister oil (>538 degrees C). The analysis of the results revealed that the thermal cracking of vacuum residue follows first order kinetics. The proposed model predicted the kinetic parameters for the thermal cracking of different residual feedstock and provided a good fit to the experimental data. (C) 2012 Elsevier Ltd. All rights reserved.