Experimental/Correlational Proposal to Relate NMR Measureables with Macroscopic Thermodynamic & Transport Properties & Directly with Corresponding States Para

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The objectives of this proposal are: to use a nuclear magnetic resonance (NMR) technique to measure the spin densities and the spin-lattice and spin-spin relaxation times of normal fluids and mixtures of normal fluids including carbon dioxide at moderate to advanced pressures; and to correlate the resulting measurements with macroscopic thermodynamic and transport properties and with corresponding states parameters. The proposed objectives constitute a significant extension from a recently developed corresponding states correlation for the relaxation times of pure liquid alkanes at near-normal pressures. The relaxation times can be correlated directly with corresponding states parameters, indicating that the Debye and Stokes-Einstein assumptions need not be invoked to relate the relaxation time to transport properties. The significance of being able to relate NMR measurables both to transport coefficients and to state variables is evident, e.g. in quantitative NMR imaging. The relationship amongst NMR measurables, such as transport properties, and corresponding states parameters suggests that multiple pathways exist from NMR measurables to macroscopic thermodynamic and transport coefficients. In recent years, a significant advance has been made by relating NMR measurables to corresponding state values for pure liquids. If these relationships can be extended to liquid mixtures, as proposed, and then demonstrated to be accurately observed in porous media, the results can have direct and important application in petroleum production studies. Industry is in need of a rapid, continuous, and accurate system for following the effects of diffusion and dispersion in the transition region when one fluid displaces a second liquid from a core by miscibility difference phenomena. Being able to observe what occurs (and how rapidly it happens) within a reservoir rock for example, would greatly facilitate transfer of new miscible oil recovery processes from the laboratory to the field.