二维吸附床双组分气体传质过程数值分析

Numerical analysis on mass transfer process of binary component air for two dimensional adsorption bed

为了深入研究吸附式空分制氧的传质过程,利用Fluent数值模拟软件对二维吸附床进行了模拟研究.模型综合考虑了气体的可压缩性、吸附床的死空间以及吸附床径向空隙率的分布,模拟结果与实验值和文献值作了对比分析,结果吻合良好.分析表明,在壁面附近存在边流效应,使得吸附剂的使用率不均,通过改变颗粒直径的大小,可以有效减小边流效应的影响;吸附过程温度变化显著,对吸附过程的传质影响较大,在数值模拟中不能忽略吸附热的影响.该数值模拟方法能够比较准确地预测吸附床内的传质过程,并为吸附系统的设计和优化提供必要的支持.

In order to investigate the mass transfer process of adsorption-type oxygen separation from air, the simulation for a two dimensional adsorption bed was carded out with Fluent numerical simulation software. The gas compressibility as well as the dead space and radial porosity distribution of adsorption bed were comprehensively considered in the model. The simulated results were compared and analyzed with those obtained from both experiments and literatures. The analysis shows that there exists the wall effect near the wall surface, which makes the utilization ratio of sorbent inhomogeneous. Through changing the diameter of particles, the influence of wall effect can be effectively reduced. The significant temperature change in the adsorption process has large effect on the mass transfer process. Therefore, the influence of adsorption heat can not be neglected in the numerical simulation. The present numerical simulation method can predict the mass transfer process for the adsorption bed more accurately, and provide the necessary support for the design and optimization of adsorption system.