Experiments on Solute Transport in Aggregated Porous Media: Are Diffusions Within Aggregates and Hydrodynamic Dispersion Independent?

摘要: Two region models for solute transport in porous media assume that hydrodynamic dispersion mobile water and diffusion within immobile regions are independent. Experimental theoretical results through a macropore indicate exchange interdependent. Experiments were carried out to investigate this problem column packed with spherical aggregates. The effective coefficient of tracer the agreggates was determined from specific experiments. dispersivity bed experiments filled nonporous beads. We took advantage dependence on density ratios between invading displaced solutions obtain set breakthrough curves corresponding situations where remains constant, whereas varies. Simulations reproduce correctly Small discrepancies noted can be corrected either by increasing or fitting external mass transfer coefficient. Increased coefficients probably reveal modification Taylor due exchange. fitted close values obtained classical correlations chemical engineering literature.