Real time determination of the presence of emulsion in a formation fluid is
accomplished using an optical probe, preferably an attenuated total reflectance
probe. The determination can then be used to appropriately increase, decrease or
leave unchanged the use of demulsification additives or other means to control
emulsion formation. The method is particularly useful for free water knock-out
separations, where a plurality of probes can be used to distinguish the location
and/or volume of emulsion, or "rag", layer and thereby to facilitate decantation
of relatively pure oil and water fractions. It can also be effectively used in
pipelines, and can optionally determine the degree of emulsification and trends
toward emulsification or demulsification.
