Method for dispersion and adsorption coefficient estimation using an analysis of pressure transition during a viscosity-switch

A method for estimating porous-media longitudinal dispersion and adsorption coefficients, the method comprising:

• introducing a first amount of a pure phase component though a porous medium;
• introducing a component having a same phase as the pure phase component through the porous medium, the component comprising a viscosifying agent having a non-linear viscosity-concentration dependence;
• introducing a second amount of the pure phase component through the porous medium;
• measuring, using a permeability analyzer, a pressure drop across the porous medium after each introduction at a plurality of intervals over a period of time;
• determining, using the measured pressure drops, a first pressure transition and a second pressure transition, each point along the first pressure transition representing a difference between the measured pressure drops across the porous medium resulting from the introduction of the first amount of the pure phase component and the introduction of the component, and each point along the second pressure transition representing the difference between the measured pressure drops across the porous medium resulting from the introduction of the component and the introduction of the second amount of the pure phase component;
• and
• analyzing the first pressure transition and the second pressure transition across the porous medium to determine a dispersion coefficient and an adsorption coefficient for the porous medium.