Arezoo Rezaei - M.Sc. student of Shahid Bahonar University, Department of Chemical Engineering, Young
Ali Mohebbi - Associate Professor, Department of Chemical Engineering, Shahid Bahonar University of Kerman
Vali Ahmad Sajjadian - Assistant Professor, Arvandan oil & gas (Research center), Tehran, Iran
Mahmood Hemmati

There are several proper methods for increasing the sweep efficiency in carbonate reservoirs i.e.increase the injection phase viscosity, wettability alteration of the rock, lowering the interfacialtension and decreasing mobility ratio. The mechanism of enhanced oil recovery by dispersed nanoparticles during polymer flooding, is not well known. In this study, a series of injectionexperiments were performed in Sandpack models after saturation with water and Fahlian light oil.Two different fluids i.e. Polyacrylamide solution and dispersed clay nanoparticles in polyacrylamid solution were used as injection fluids. The result showed that the polymer solutionincreased oil recovery to 10% while the clay nanoparticles in polymer solution caused enhancedoil recovery up to 12% . This research showed that higher viscosity of displacing fluid resulted in more efficient displacement; that is, as the viscosity of displacing fluid was increased, mobilityratio was decreased and displacement efficiency was increased. also the results showed that using the claynanoparticles during polymer flooding increased polymer strength at high temprature and salinity.

Mobility ratio, Polymer flooding, Clay nanoparticles, Polymer strength,Polyacrylamid