In this work, a comprehensive pore-network model is developed for simulation of multicomponent diffusion through a porous media. In a pore-network model, the porous media structure is considered to be a three-dimensional regular network of nodes and the pores that are connecting them to each other. In this paper, a pore-network model was used to compute the diffusivity of natural gas, which consists of methane, water, and mercaptan, on zeolite 13X. Zeolite 13X is used in the temperature swing adsorption (TSA) process in South Pars in the Middle East. The effective diffusivity of these gases is achieved according to Knudsen diffusion, molecular diffusion, viscous flow, and surface diffusion conditions on three-dimensional networks simultaneously. Results were compared with reported data from literature and were in good agreement with them. In this modeling, the effect of the pore volume reduction on the cross-section area of pores, which may result in reduction in diffusivity of pores, has been considered. Also, the effects of pressure, temperature, and Z connectivity on effective diffusivity of multicomponent gas have been investigated.

中文翻译：

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基于孔网络模型的多孔介质多组分扩散模拟

在这项工作中，开发了一个综合的孔隙网络模型来模拟通过多孔介质的多组分扩散。在孔网络模型中，多孔介质结构被认为是节点和连接它们的孔的三维规则网络。在本文中，使用孔隙网络模型计算由甲烷，水和硫醇组成的天然气在13X沸石上的扩散率。13X沸石用于中东南部帕尔斯（South Pars）的变温吸附（TSA）工艺中。这些气体的有效扩散率是同时根据三维网络上的Knudsen扩散，分子扩散，粘性流和表面扩散条件实现的。将结果与文献报道的数据进行了比较，并与之相吻合。在该模型中，已经考虑了孔体积减小对孔的横截面积的影响，这可能导致孔的扩散率降低。此外，还研究了压力，温度和Z连接性对多组分气体有效扩散率的影响。