Quantitative measurements of injections into porous media with contrast based MRI

Porous flow occurs in a wide range of materials and applies to many commercially relevant applications such as oil recovery, chemical reactors and contaminant transport in soils. Typically, breakthrough and pressure curves of column floods are used in the laboratory characterization of these materials. These characterization methods lack the detail to easily and unambiguously resolve flow mechanisms with similar effects at the core scale that can dominate at the aquifer or oil field scale, as well as the effects of geometry that control the flow at interfaces as in a perforated well or the inlet of an improperly designed column. Non-invasive imaging techniques such as MRI have been shown to provide a far more detailed characterization of the properties of the solid matrix and flow, but usually focus on the intrinsic flow properties of porous media or matching a numerical model to a complex flow system. We show that these MRI techniques, utilizing paramagnetic tagging in combination with a carefully controlled and ideal flow system, can quantitatively characterize the effects of geometry and intrinsic flow properties for a point injection into a core. The use of a carefully controlled and 'idealized' system is essential to be able to isolate and match predicted effects from geometry and extract subtle flow processes omitted in the model that would be hidden in a more heterogeneous system. This approach provides not only a tool to understand the behavior of intentional boundary effects, but also one to diagnose the unintentional ones that often degrade the data from routine column flood measurements.