Foundation Of The Lumped Reactions Kinetic Model For FDFCC Process

Comprehensive summaries of the development of the maximizing propene technologies for the FCC (Fluid Catalytic Cracking) process and the lumping kinetic models at home and abroad were reviewed in this paper. Based on the features and reaction mechanism of Flexible Dual-riser Fluid Catalytic Cracking-â…¢(FDFCC-â…¢) process which can maximize propene yield and reduce olefins content in gasoline, reaction networks and kinetic equations of 10-lumped kinetic model for heavy oil riser reactor and 7-lumped kinetic model for gasoline riser reactor were established respectively with the help of the data from industry and pilot plant. Differential equation was solved by 4-step Runge-Kutta method and its results were optimized by BFGS (Broyde,Fletcher,Goldfarb and Shannon) method. The softwares for the calculation parameters of two reaction networks were programmed by Microsoft C++. And then kinetic parameters for the 10-lumped kinetic model and 7-lumped kinetic model were worked out according to the data from pilot plant. The verification results of pilot plant show that these parameters are reliable because the relative errors between predicted values and practical data are less than 5%. On the basis of the parameters, unit factors were set to eliminate the errors during the process of industrial scale-up. The verification results of industrial data show that these parameters and kinetic models are reliable because the relative errors between predicted values and practical data are less than 5%. Finally, a series of operational performance charts were drawn for a commercial FDFCC unit with the help of the models given above. The charts show that the effects of reaction temperature, space velocity, catalyst to oil ratio (cat/oil) and recycle ratio on the products distribution parallel to reaction mechanism and characters of FDFCC-â…¢. Therefore, these charts could be used to guide the optimization of practical operation conditions.