Flow behaviour of oil‐in‐water emulsions

Abstract

The rheological behaviour of concentrated oil-in-water emulsions has been investigated using the Weissenberg Rheogoniometer. The oil concentration has been varied from 40 to 95 volume percent. The effects of shear rate and oil concentration on the viscosity have been determined. From the rheological data, the maximum attainable oil concentration in the emulsion has been estimated and is introduced as a parameter in the relationship between relative viscosity and oil concentration to account for certain variations in the emulsion characteristics. Empirical equations have been obtained which correlate zero shear rate viscosity and infinite shear viscosity as a function of reduced oil concentration. Comparison has been made between the emulsion viscosity and the solid-liquid suspension viscosity at high dispersed phase concentration. Estimated maximum attainable oil concentration is found to be in close agreement with the actual maximum concentration that could be achieved experimentally.On a ttudit le comportement rhtologique d'tmulsions concentrtes d'huile dans I'eau, en employant la rhbogoniomktre de Weissenberg. On a fait varit la concentration d'huile entre 40 et 95%, en volume, et I'on a dttermint les effets, sur la viscositt, de la vitesse de cisaillement et de la concentration de I'huile. On a CvaluC, B partir des rtsultats rhCologiques, la concentration maximale de I'huile dans l'tmulsion; on a introduit cette concentration comme paramktre dans la relation entre la viscositk relative et la concentration de I'huile, pour expliquer certaines variations dans les caractCristiques des tmulsions. On a obtenu des Cquations empiriques qui ont permis de corrtler la viscositt B vitesse de cisaillement nulle et B vitesse de cisaillement infinie, en fonction d'une concentration kduite d'huile. On a fait une comparaison, entre la viscositt de I'tmulsion et la viscositt d'une suspension de matfres solides dans un liquide, pour une forte concentration de la phase disperste. On a trouvt que la concentration maximale de I'huile estimte concorde bien avec la concentration maximale obtenue exp6rimentalement. rude oils produced from secondary and tertiary oil re-C covery projects are very often in the form of stable oil-in-water emulsions. Oil-in-water emulsions are also en-

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“…The lower sensitivity of the UV detector was also a limiting factor in the procession of the measurement. injection (1) injection (2) injection (3) injection (4) (Fig. 3.5).…”

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