Fcc Process Characteristics Of Components Of The Kinetic Model And Reaction - Regeneration System Simulation Study

The purpose of this work is to develop a predictive simulation models on the Riser —type catalytic cracking reactor and Fluidized — bed catalytic cracking regenerator system of the Fluid Catalytic Cracking Units (FCCU).On the basis of these models, we have developed a series of computer models (software), used to calculate the compositions and properations of feedstock, to simulate the reactor/regerator chemical reactions, to predicte the product distribution, to analysis the flow, the heat— and mass—transfer of the commercial plant of FCCUs.Huge numbers of hydrocarbon spedies interreacte with each other through exothermic reactions (cracking) or endothermic reactions (regenerating) in a gas —solid two—phase flow reactor (riser reactor and fluidized—bed regenerator) made each of the above simulation models challengeable and very difficulity to solve.1. Character the catalytic cracking feedstock and product oilWe have examined many studies on catalytic cracking reaction, such as the hydrocarbon molecular models and the lumped models, and found that, with (?)ealtively wide range of hydrocarbon mixture as feedstock and reactant, these models are not suitable to use in simulating the industrial FCCU reactor.We presented a new method to character the feedstock and product oil on the basis of 250 reactantes and production mixture species with its TBP(True Boiling Point)distillation analysis data, these 250 hydrocarbons chosed are called Characterized Hydrocarbons (CHB). A detail studies on feedstock and diesel oil production of an industrial FCCU process giving in this dissertation showed that CHB method is a relatively simple method that can be used to calculate the properties and compositions of a wide range of hydrocarbon mixture with high accuracy.2. Kinetic models of Characterized Hydrocarbon of FCCUCracking hehavior of different kinds of hydrocarbons have been described by carbenium mechanistic schemes. Kinetic models of Characterized hydrocarbon imbedded the reaction mechanism underling the rate of interconveration of the different kinds of hydrocarbon reac-tants, so it is suitable to use in calculating the conversion extent of feedstock and productive properties with wide range of hydyocarbon mixture as catalytic cracking feedstock.As the mess of kinetic reaction constantes are not available by expermental data, we present here a Logistic function type models to calculate the kinetic reaction constantes with resonable accuracy.