甲醇水蒸气重整制氢固定床反应器的数学模拟

Mathematical simulation of fixed-bed reactor for hydrogen production from methanol steam reforming

建立二维拟均相固定床反应器数学模型用于描述Cu_(50)Zn_(30)Ce_(10)Al_(10)催化剂颗粒的甲醇水蒸气重整制氢反应过程,该模型由流体相的质量、热量和动量传递方程组成,耦合催化剂颗粒内部的扩散-反应模型。通过将模型预测值与实验数据进行比较,验证反应器数学模型的准确性。在此基础上,分析关键组分CO_(2)和CO的效率因子随床层轴向的变化规律以及催化剂床层的轴径向温度分布。结果表明:催化剂床层的轴径向温差较大,导致CO_(2)效率因子变化较大,而CO由于浓度低,反应速率慢,其效率因子变化不明显。

A two-dimensional pseudo homogeneous fixed bed reactor mathematical model was developed to describe the hydrogen production process through steam reforming of methanol over a Cu_(50)Zn_(30)Ce_(10)Al_(10) catalyst. The model consisted of mass, heat and momentum transfer equations in the fluid phase, as well as the diffusion-reaction equations in the particle(catalyst) phase. The reliability of the model was verified by comparing the model predictions with experimental data. Moreover, the variation of effectiveness factors of the key components CO_(2)and CO along the axial direction of the catalyst bed was studied, and the temperature profiles in both axial and radial directions were analyzed. The results show that the temperature difference in both directions is so high that the effectiveness factor of CO_(2)varies greatly, while the effectiveness factor of CO changes little due to its low concentration and low reaction rate.