Study On Steady State Mechanism Model Of Catalytic Cracking Reactor-Regenerator System

Fluid catalytic cracking unit is one of the important production equipments for heavy oil turning into light oil in refining industry field.After nearly 60 years' development,the total processing capacity of FCCU in China has reached 150Mt/a,it is of great significance to the optimization and innovative research of its technology.The main difficulties of FCCU modeling include the large number of cracking reactions in the riser,optimization and identification of kinetic parameters,the modeling of the whole reaction system has the characteristics of nonlinearity,strong coupling and thermal effect.The purpose of this paper is to study and optimize the steady state mechanism model of FCCU reactor-regenerator system,the detail work is as follows:(1)Basing on special pseudo-components characteristic method,after analyzing the multiple solutions and sensitivity of the six parameters {k0,v,?,E0,A,B)proposed by Zhang et al,a three kinetic parameter(k0,v,?)riser model is established.To test this model,three practical riser units and six sets of crude oil data are introduced for model simulation and prediction.The results show that the three kinetic parameters model proposed in this paper are locally identifiable.(2)Basing on the regenerator's model of Han and Chung,a steady state model of regenerator is established in two areas(dense phase/dilute phase)and uses the GDEM accelerated iterative algorithm to calculate the convergence of the model.The variation trend of important iterative variables,such as the composition of the flue gas and the internal temperature of the regenerator,is studied.The simulation results show that it is in line with the actual production demand.(3)Establishing the whole steady state model of FCCU reactor-regenerator system.To verify the results,this paper used the industrial production data of the Sinopec Jiujiang refinery.The results show that the speed effect and the model accuracy of the GDEM are significant.Investigating the yield of the products out of the riser and the content of the flue gas composition by changing the operating conditions of COR and ventilation volume.