应用正交配置法模拟固定床吸附过程

Solution of adsorption model in a fixed bed adsorber using orthogonal collocation method based on planar, cylindrical and sperical adsorbents

建立的固定床吸附模型以固体表面扩散为基础 ,同时考虑吸附剂颗粒内外扩散阻力、床层轴向弥散、非线性吸附平衡和吸附剂形状的影响 .应用非矩阵法构造了权函数分别为W (x) =1和W(x) =1-x ,最大配置点数为 2 0 ,适用于非对称性问题的正交配置表 .应用正交配置法求解吸附数学模型 ,并利用文献数值解和文献实验数据检验数值模拟结果 .

A mathematical model of fixed bed adsorber is presented, which describes the solid diffusion mechanism considering both internal and external mass transfer resistance. The model accounts for the concentration dependence of intraparticle surface diffusion coefficient,and for the axial diffusion. The nonlinear isotherms, i.e. Langmuir's or Freundlich's isotherms, are used to describe the adsorption equilibrium. The orthogonal collocation tables for unsymmetric geometry based on weighting functions W(x)=1 and W(x)=1-x are constructed by the non-matrix method, with different numbers of collocation pointing from 1 to 20. Numerical solutions are obtained by using the orthogonal collocation method and tested by comparing numerical solutions with experimental data in the literature.