Using Diffusion and Electrical Measurements to Assess Tortuosity of Porous Media
详细信息 查看全文
- 作者：Ali. A. Garrouch ; Liaqat Ali ; and Fuad Qasem
- 刊名：Industrial & Engineering Chemistry Research
- 出版年：2001
- 出版时间：October 3, 2001
- 年：2001
- 卷：40
- 期：20
- 页码：4363 - 4369
- 全文大小：83K
- 年卷期：v.40,no.20(October 3, 2001)
- ISSN：1520-5045
文摘
This study puts under scrutiny the unique relationship between molecular diffusion and electricalconductivity data for Berea, Okesa, Tallant, and Elgin sandstones ranging in permeability from83 to 2502 md. The experimental setups used for generating the investigated data featured theuse of a four-electrode circuit that canceled the effects of contact electrode polarization and adiffusion flow system that allowed on-line calibration and established a stable baseline. Theeffective molecular diffusion coefficients (De) for these porous media were estimated by matchingsimulated concentration profiles with measured ones. Tortuosity values were calculated by usingmolecular diffusivity models and their analogous electrical conductivity models. Tortuosity valuescalculated from diffusion measurements (using the Brakel and Heertjes model; Int. J. HeatTransfer 1974, 17, 1093) matched reasonably well with those values estimated using Pirson'selectrical model (Geologic Well Log Analysis; Gulf Publishing: Houston, TX, 1983). These resultsindicate the superiority of the latter model over a large number of formation-factor-based modelsfor estimating rock tortuosity. This study helped in the selection of adequate tortuosity modelsfor characterizing sandstone rocks and verified the similarity between electrical conductivityand molecular diffusivity in sandstone rocks.