Effect of Temperature and Salinity on Swelling Ratio of Reinforced Particle Gels Used for Water Shutoff

Abstract

Summary Preformed Particle Gel (PPG) is one of the new and effective techniques for minimizing the surplus water production during hydrocarbon recovery and improving sweep efficiency of mature oil fields by plugging super-high permeable streaks and induced fractures. The success of PPG treatment in plugging the thief zones mainly depends on its swelling ratio in reservoir conditions. In the present study, a nano fly ash reinforced PPG is synthesized using acrylamide as a monomer, N,N'-Methylenebis (acrylamide) as crosslinker, potassium persulfate as initiator and nano fly ash as a mechanical modifier. The swelling ratio of reinforced PPG is evaluated in the laboratory at various reservoir conditions viz. temperature (40°C–80°C) and salinity (0-60000 ppm) according to Design of Experiments (DOEs) suggested by Central Composite Design (CCD) assisted Response Surface Methodology (RSM). An enhanced swelling ratio with a maximum value of 72.23 g/g is predicted by the model at high reservoir temperature (64.83°C) and low water salinity (974.83 ppm), however, the results have shown that the effect of water salinity on the swelling ratio of PPG is more predominant than reservoir temperature.