A Kinetic Model for the Prediction of Hydrocracker Yields

Abstract

A description of the yield changes that occur during hydrocracking is complicated by the large number of different molecules involved. Here a kinetic model is discussed that represents this wide spectrum of compounds as a series of 50°F boiling range cuts. Each of the heavier cuts cracks via a first-order reaction to form a series of lighter cuts. One parameter describes the effect of boiling point on the rate constant. Two other parameters determine what products will be generated as each cut cracks. With a feed distillation and values for these three parameters, the model predicts product distillation curves as a function of conversion level for both once-through and recycle liquid operation with a standard error of about 1%. Values for these parameters are given for a variety of feeds and catalysts. They depend on catalyst type and feed paraffin content.

Three‐phase reactor model for hydrotreating in pilot trickle‐bed reactors

“…These data were used for estimating liquid properties using standard procedures as published by Ahmed (1989) or in the APZ Handbook (1984). Furthermore, the boiling-point distribution is a simple measure for characterizing the amount of hydrocracking taking place during hydroprocessing (Stangeland, 1974). The content of aromatic C-atoms was determined by 13C-NMR (nuclear magnetic resonance), the Brown-Ladner method (Kagler, 1987) using 'H-NMR data in combination with the ultimate analysis of carbon and hydrogen, and by the n-d-M method.…”

Kinetic model for hydrocracking of heavy oil in a CSTR involving short term catalyst deactivation

“…Different kinetic approaches have been reported in the literature for the hydrocracking of oil fractions (lumping approach, continuous kinetics lumping, single event model) [1][2][3][4][5][6][7][8], but only a few deal with the hydrocracking of heavy oil. Because vacuum gas oil has been mostly used as feed, catalyst deactivation has been neglected.…”

5-Lumps kinetic modeling, simulation and optimization for hydrotreating of atmospheric crude oil residue

“…However, the available analytical techniques are incapable to identify the detailed molecular level of heavy feedstocks [9]. There are other types of modeling used to determine reactor performance such as hybrid modeling which is a first-principles model (FPM) based on the pseudo-component approach coupled with neural network(s) in different hybrid architectures [10], Combination of Genetic Algorithm and Sequential Quadratic Programming which based on genetic algorithm and sequential quadratic programming to determine the significant reactions and their corresponding rate constants [11], and some used kinetics to extract information about yield [12] and other model of hydrocracking reactor [13]. The lumped kinetic models are commonly used in modeling the hydrocracking of heavy feedstocks such as atmospheric vacuum resides.…”