Abstract In the methanol-to-olefins (MTO) process, coke deposition is closely related to the selectivity of light olefins. Previous simulations of different-sized MTO reactors using two-fluid model (TFM) combined with the EMMS (energy minimization multi-scale)-based drag well predict the hydrodynamic behaviors but poorly predict the product distribution of large reactors due to the unreasonable prediction in coke distribution. In this study, the TFM integrated with the EMMS-based drag is still employed, but the solid phase is treated as a mixture of a series of species with different coke contents. Because the coke content depends on the age of catalyst particles inside the reactor, a continuous stirred tank reactor (CSTR) model mimicking turbulent fluidization while considering the age distribution of catalysts is established to predict the initial coke distribution for speeding up simulation. Compared with the previous simulation without consideration of coke distribution, this approach increases the computational time by a factor of 36% and shows no influence on hydrodynamic predictions, but the reaction quantities such as methanol conversion, mass fractions of gaseous products and selectivity of light olefins, are better predicted.

中文翻译：

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考虑焦炭分布的大型甲醇制烯烃流化床反应器模拟

摘要 在甲醇制烯烃（MTO）过程中，焦炭沉积与轻质烯烃的选择性密切相关。先前使用双流体模型 (TFM) 结合基于 EMMS（能量最小化多尺度）的阻力井对不同尺寸的 MTO 反应器进行的模拟预测了流体动力学行为，但由于在焦炭分布。在这项研究中，TFM 与基于 EMMS 的阻力相结合仍然被使用，但固相被视为一系列具有不同焦炭含量的物种的混合物。因为焦炭含量取决于反应器内催化剂颗粒的年龄，建立了模拟湍流流化同时考虑催化剂老化分布的连续搅拌釜反应器 (CSTR) 模型，以预测初始焦炭分布以加快模拟速度。与之前不考虑焦炭分布的模拟相比，这种方法将计算时间增加了 36%，并且对流体动力学预测没有影响，但反应量如甲醇转化率、气态产物的质量分数和轻烯烃的选择性，更好地预测。