Simulation Of Methanol To Olefins (MTO) Fluidized Bed Reactor

Methanol to olefins (MTO) is an important coal chemical process. In this paper, modeling and simulation of the turbulent fluidized bed reactor applied to MTO process were carried out. The works include the following three parts:1. Reaction kinetics of MTO processA reaction kinetic model on SAPO-34 catalyst including six lumping components was developed. The model adopted the'Hydrocarbon Pool'parallel and coke deactivation mechanism, and the latest development of kinetic mechanism and scheme for MTO process, which described the reaction behavior in the periods of induction, uniform deactivation and fast deactivation. It considered the influences of coke, water and mass-transfer. The available experiment data in literatures were used to fit the model parameters. This model agreed well with the experiment data.2. Fluidized bed reactor simulation.A turbulent fluidized bed reactor model was developed for the MTO process, which included two parts. First is the catalyst particle model, which described the catalyst deactivation, caused by the coke deposit following the particle residence time, and its influence to the conversion of MeOH and the products distribution. Second is the two-phase and two-region fluidized bed model, which included the flow behavior of the fluidized bed, mass-transfer and MTO reaction. In order to validate this model, a published pilot data for MTO process on fluidized bed was used to test the model. The results agreed well with the experiment data.3. Model applicationThe model was employed to discuss the influence factors on MTO process. Impacts of mass-transfer, coke content, catalyst residence time, gas velocity, gas back-mixing, the feed H2O/MeOH ratio were investigated. In addition a novel two-stage reactor model was compared to the ordinary single reactor mode. The models and results in this paper would provide guidance for the design and operating optimization of the industrial MTO fluidized bed reactor.