Comparison on hydrocarbon generation kinetic models

Key words:  kinetic model  kinetic parameters  apparent activation energy  pre exponential factor

Abstract:

Different kinetic models including overall reaction model, normal distribution model, Weibull distribution model and discrete distribution model were established, and kinetic parameters were optimized based on systematic research of hydrocarbon generation kinetics experiment for twenty three source rocks. Then the optimized results and hydrocarbon generation kinetic characteristics of different type kerogen were compared. The results show that Gaussian distribution model has the worst fitting effect, followed by overall reaction model and Weibull distribution model, and the discrete distribution model has the best fitting effect. Apparent activation energy increases gradually with the pre exponential factors increasing, and the apparent activation energy of type II2 III kerogen is larger than that of type I, and that of type II1 is the smallest. It is recommend the parallel first order kinetic model with a discrete distribution activation energies be used when the hydrocarbon generation kinetic method is applied to appraise oil gas resources and to study hydrocarbon generation kinetic characteristics and the isotope fractionation kinetics.