Parallel column models were first proposed in the 1950s for investigating the sensitivity of the HETP in a packed column to maldistribution. Although it is possible to develop a parallel column model using a process simulator, it may take considerable effort to arrange and specify the columns.

Recently, we have described what we call a Parallel Column Model (PCM) with the aim of making it easier to model Dividing Wall Columns (DWCs), we realized that it should also be possible to use the PCM to model maldistribution in packed columns. Both equilibrium stage and rate-based column models can easily be used within this framework.

In this paper we review the literature on simulating packed columns with maldistribution. We also show how easily our PCM may be used to describe maldistribution in packed columns and show how our results match the obtained results of earlier papers. We propose a simple bed effectiveness approximation that can use the results from a regular column simulation and assign stages to specific packed beds such that such that the resulting column suffers less from liquid maldistribution. We illustrate the use of this approximation with two practical examples involving the design of commercial scale columns.

平行柱模型最早是在1950年代提出的，用于研究填充柱中HETP对分布不均的敏感性。尽管可以使用过程模拟器来开发并行列模型，但可能需要花费大量精力来安排和指定列。

最近，我们描述了所谓的平行柱模型（PCM），目的是简化对分隔壁柱（DWC）的建模，我们意识到也可以使用PCM对填充柱中的分布不均进行建模。平衡阶段模型和基于速率的色谱柱模型都可以在此框架内轻松使用。

在本文中，我们回顾了有关模拟分布不均的填充柱的文献。我们还展示了我们的PCM可以多么容易地用来描述填充柱中的分布不均，并展示了我们的结果如何与早期论文的结果相匹配。我们提出了一种简单的床效近似方法，可以使用常规色谱柱模拟的结果，并将阶段分配给特定的填充床，以使所得的色谱柱受液体分布不均的影响较小。我们通过两个涉及商业规模色谱柱设计的实际示例来说明这种近似的用法。