Pipeline Flow Behavior of Water-in-Oil Emulsions with and without a Polymeric Additive

New experimental results are presented on the pipeline flow behavior of water-in-oil (W/O) emulsions with and without a polymeric additive in the aqueous phase. The emulsions were prepared from three different oils of different viscosities (2.5 mPa s for EDM-244, 6 mPa s for EDM-Monarch, and 5.4 mPa s for Shell Pella, at 25 degrees C). The W/O emulsions prepared from EDM-244 and EDM-Monarch oils (without any polymeric additive in the dispersed aqueous phase) exhibited drag reduction behavior in turbulent flow. The turbulent friction factor data of the emulsions fell well below the Blasius equation. The W/O emulsions prepared from EDM-244 oil exhibited stronger drag reduction as compared with the EDM-Monarch oil. The W/O emulsions prepared from Shell Pella oil exhibited negligible drag reduction in turbulent flow and their friction factor data followed the Blasius equation. The Shell Pella emulsions were more stable than the EDM-244 and EDM-Monarch emulsions. When left unstirred, the EDM-244 and EDM-Monarch emulsions quickly coalesced into separate oil and water phases whereas the Shell Pella emulsions took a significantly longer time to phase separate. The Shell Pella oil emulsions were also milkier than the EDM emulsions. The addition of a polymer to the dispersed aqueous phase of the W/O emulsions had a significant effect on the turbulent drag reduction behavior.