Main content area

CFD Simulation of Oxidative Coupling of Methane in Fluidized-Bed Reactors: A Detailed Analysis of Flow-Reaction Characteristics and Operating Conditions

Salehi, Mohammad-Sadegh, Askarishahi, Maryam, Godini, Hamid Reza, Schomäcker, Reinhard, Wozny, Günter
Industrial & Engineering Chemistry Research 2016 v.55 no.5 pp. 1149-1163
engineering, ethane, ethylene, fluidized beds, kinetics, methane, models, steam
The effect of operating conditions and feed characteristics on the performance of the oxidative coupling of methane (OCM) reactor was investigated numerically by analyzing the concentration of the reactants and products along the fluidized-bed reactor. Aimed at modeling such multiphase flow, a two-fluid model based on the kinetic theory of granular flow was applied. The impact of the kinetic model was conceptually investigated through investigation of the observed reaction pathways along the reactor under various feed dilutions. The overall predicted selectivity toward ethylene and ethane (C₂-products) and methane conversion were in agreement with the experimental data. In detail, the results of simulations demonstrated that the fast acceleration of ethylene steam reforming at T > 800 °C results in C₂ selectivity peaking around T = 800 °C. However, an increase in pressure from 1 bar to 3 bar slightly decreases the C₂ selectivity. At identical space velocity, a decrease in CH₄/O₂ ratio improves the C₂ yield.