SIAM Journal on Applied Mathematics, Volume 81, Issue 2, Page 591-619, January 2021.
Many chemical filters contain reactive components where harmful substances are removed or transformed. In this paper, we derive a homogenized model for a flue-gas filter that converts sulphur dioxide into liquid sulphuric acid. We consider a microscale domain, focused on a single catalytic pellet, and homogenize over both the gaseous and the liquid phase to obtain macroscale equations for the concentration of sulphur dioxide and the thickness of the liquid sulphuric acid layer that grows around the pellets. We explore two interesting limits of the homogenized model, in which the reaction rate at the pellet surface is small, and where the mass transfer across the gas--liquid interface is small, respectively. We then couple the macroscale equations to an equation governing the external gas flow through the filter. We solve the resulting model and consider asymptotic reductions based on the filter geometry. We consider two distinguished limits and, for one of them, obtain an explicit solution for the sulphur dioxide concentration and the void fraction in the filter. We vary parameters such as the gas speed and establish the operating regimes for effective cleansing of flue gas.

中文翻译：

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反应过滤器的均质化模型

SIAM应用数学杂志，第81卷，第2期，第591-619页，2021年1月。
许多化学过滤器均含有反应性成分，可去除或转化有害物质。在本文中，我们导出了烟气过滤器的均质模型，该模型将二氧化硫转化为液态硫酸。我们考虑一个微尺度域，集中在单个催化颗粒上，并在气相和液相上均化以获得宏观模型方程，以获取二氧化硫的浓度和在颗粒周围生长的液态硫酸层厚度的宏观方程。我们探索了均质模型的两个有趣的局限性，即在颗粒表面的反应速率很小，并且在气液界面上的传质很小。然后，我们将宏观方程式与控制通过过滤器的外部气体流量的方程式耦合。我们求解结果模型，并考虑基于滤波器几何形状的渐近约简。我们考虑了两个不同的限制，其中一个限制为过滤器中的二氧化硫浓度和空隙率提供了一个明确的解决方案。我们改变诸如气体速度之类的参数，并建立有效净化烟气的操作方案。