Journal of Colloid and Interface Science, Vol.315, No.2, 607-619, 2007
Water in oil emulsion droplet size characterization using a pulsed field gradient with diffusion editing (PFG-DE) NMR technique
This paper describes a proton nuclear magnetic resonance (NMR) technique, pulsed field gradient with diffusion editing (PFG-DE), to quantify drop size distributions of brine/crude oil emulsions. The drop size distributions obtained from this technique were compared to results from the traditional pulsed field gradient (PFG) technique. The PFG-DE technique provides both transverse relaxation (T-2) and drop size distributions simultaneously. In addition, the PFG-DE technique does not assume a form of the drop size distribution. An algorithm for the selection of the optimal parameters to use in a PFG-DE measurement is described in this paper. The PFG-DE technique is shown to have the ability to resolve drop size distributions when the T-2 distribution of the emulsified brine overlaps either the crude oil or the bulk brine T-2 distribution. Finally, the PFG-DE technique is shown to have the ability to resolve a bimodal drop size distribution. Published by Elsevier Inc.