Simulation And Optimization Of Counter-Current Continuous Reforming Regenerator

Catalytic reforming could transform naphtha into aromatics-rich reforming oil and produces hydrogen as a by-product,so the catalytic reforming plays an important role in the whole petroleum refining process.Catalyst is one of the key factors in the reactions of continuous catalytic reforming unit.However,the catalyst is easily deactivated by the coke deposition,which affects the activity and selectivity of the catalyst,so the continuous regeneration of catalyst is necessary for the reforming process.The simulation of the regeneration process can provide guidance for the operation optimization of industrial units.This paper is based on the regenerator of a 600,000-ton/a counter-current continuous reforming unit of a Sinopec refinery as the research object.According to the reaction process of coke combustion,a mathematical model is established and the differential equation describing the regenerator model is obtained.At present,real-time optimization is widely used in chemical production,but real-time optimization has a high degree of rigor on calculation time.The equation-oriented method is to solve all the equations of the description model together,so its calculation time is less which can meet the requirements of real-time optimization.The orthogonal collocation method and finite difference method was adopted to discrete the differential equations and sequential quadratic programming(SQP)algorithm was used to solve the algebraic equations.In this study,the kinetic parameters were estimated,with the sum of relative errors between actual value and simulate value as optimization objective function,and seven sets of industrial operation data were adopted to validate the reliability of model prediction with the estimated kinetic parameters.The results show that between the simulation value and the actual data from the regenerator,the average relative error of oxygen content in two stages is less than 6%,and the average relative error of temperature at the outlet of regeneration gas in one stage is 0.8%.The factors affecting the regeneration process were analyzed,and the trend is consistent with the factory data.In addition,according to the regeneration requirements,the condition optimization of regeneration can provide real-time guidance for industrial units.