合成气一步法制二甲醚管壳型反应器二维数字模型及合成系统模拟

发布时间：2018-06-23 14:41

  本文选题：合成气 + 二甲醚合成　； 参考：《华东理工大学》2011年硕士论文

【摘要】：对煤基合成气一步法制二甲醚反应体系的平衡转化率及甲醇合成反应与甲醇脱水反应的协同效应进行了研究。建立了合成气一步法制二甲醚管壳式固定床反应器的二维拟均相数学模型,模拟设计了年产20万吨二甲醚、副产5万吨甲醇的反应器。采用Aspen Plus流程模拟软件对合成气一步法制二甲醚合成系统进行模拟。 在3.0～8.0MPa范围内,总碳(CO+CO2)的平衡转化率随着温度升高而降低,随着压力的升高而增大。甲醇脱水反应与甲醇合成反应的协同作用能提高总碳的单程转化率。 建立了管壳式固定床反应器的二维模型,采用有限差分和龙格库塔相结合的方法(MOL法)求解。模拟计算结果显示,当反应管径为φ42×2mm时,标况下反应器床层最大径向温度差为4.1℃,组分最大摩尔分率差为0.88%；热点温度为262.76℃,热点位置在离反应器进口2.1m处。总碳单程转化率50.68%,二甲醚选择性87.41%,甲醇选择性12.59%。反应管直径、入塔气量、沸腾水温度、原料气CO含量对床层温度分布、总碳单程转化率、甲醇及二甲醚选择性都有较大影响。 对年产20万吨二甲醚,副产5万吨甲醇的标准工况进行模拟计算,确定循环比为2.78,入塔气氢碳比为4.86,全塔压降为0.3MPa,每生产一吨二甲醚消耗4862.6Nm3新鲜合成气,副产1.92吨中压蒸汽,副产0.3吨粗甲醇,消耗循环压缩功55kw。同时,反应器能在50%生产负荷和110%生产负荷下平稳运行。
[Abstract]:The equilibrium conversion and synergistic effect between methanol synthesis and methanol dehydration were studied in the system of one-step synthesis of dimethyl ether from coal-based syngas. A two-dimensional quasi-homogeneous mathematical model for the synthesis gas one-step dimethyl ether tube and shell fixed-bed reactor was established. The reactor with an annual output of 200000 tons of dimethyl ether and a by-product of 50,000 tons of methanol was simulated and designed. The synthesis system of Dimethyl ether from syngas was simulated by Aspen Plus process simulation software. In the range of 3.0 ~ 8.0 MPA, the equilibrium conversion of total carbon (CO _ 2) decreases with the increase of temperature and increases with the increase of pressure. The synergistic effect of methanol dehydration and methanol synthesis can improve the one-pass conversion of total carbon. A two-dimensional model of a tube-shell fixed-bed reactor was established and solved by the combination of finite difference method and Runge-Kutta method (MOL method). The simulation results show that when the diameter of reactor is 蠁 42 脳 2mm, the maximum radial temperature difference of reactor bed is 4.1 鈩，

本文编号：2057463