Experimental study of drag reduction of polymer-polymer mixtures in horizontal dispersed oil-water flow

An experimental investigation of the effect of various mixtures of different polymers on drag reduction was studied in a dispersed horizontal oil-water flow. The study was carried out in a horizontal pipe flow loop system of 30.6-mm ID and 24 m length. All the polymers are anionic water-soluble polymers prepared in 1000 ppm master solution and injected at different flow rates to achieve polymer concentrations in the range of 5 to 30 ppm in the water phase. As expected, the percentage drag reductions of the individual polymers and of the binary polymer mixtures increased with the increase in the mixture velocity but decreased with the increase in the oil fraction. It has been found that the drag reduction of the mixed polymer solution is higher than the drag reduction of the lower molecular weight polymer. In most of the cases, the drag reduction of the binary mixtures shows a positive deviation from the additive straight lines. The positive deviation is more dominant for the mixture of the high and low molecular weight polymers than the mixture of the high and medium molecular weight polymers. Also, the drag reductions of the mixture of the high and low molecular weight polymers are higher than the drag reductions of the mixture of the high and medium molecular weight polymers. Finally, although positive deviation was observed in this study, no synergism was obtained for all the investigated polymer-polymer mixtures conditions. (C) 2017 Elsevier Inc. All rights reserved.