Different approaches to modeling the gas phase polymerization of ethylene that have been considered in the literature are reviewed. It is shown that while simple, well-mixed models can give an adequate representation of the average performance of a given polymerization reactor, they do not allow one to analyze certain modeling problems such as the existence of temperature gradients or particle segregation, nor can they be used to treat operational modes such as condensed cooling where there can be up to three different phases in different parts of the reactor. For this, more complex models are required. These can take the form of compartmentalized models or even models based on computation fluid dynamics. However, long computational times can be required to fully exploit these models. Furthermore, significant progress needs to be made if one needs to address important phenomena such as agglomeration or particle attrition during polymerization.

中文翻译：

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气相聚乙烯反应器——建模方法的批判性回顾

回顾了文献中考虑过的模拟乙烯气相聚合的不同方法。结果表明，虽然简单、混合良好的模型可以充分表示给定聚合反应器的平均性能，但它们不允许分析某些建模问题，例如温度梯度或颗粒分离的存在，也不能用于处理操作模式，例如冷凝冷却，其中反应器的不同部分最多可以有三个不同的阶段。为此，需要更复杂的模型。这些可以采用分区模型甚至基于计算流体动力学的模型的形式。然而，充分利用这些模型可能需要很长的计算时间。此外，