Effect of Amphiphilic CaCO3 Nanoparticles on the Plant Surfactant Saponin Solution on the Oil-Water Interface: A Feasibility Research of Enhanced Oil Recovery

In order to solve the serious problem of oil shortage,the improvementof the emulsification effect of surfactants using nanoparticles wasproposed to enhance oil recovery. In this work, first, an amphiphilicnano-calcium carbonate (ANCC) was synthesized, and the dispersioneffect of ANCC in saponin solution was studied. It can be found fromresults that the dispersion effect of ANCC was the best in 5000 ppmof saponin solution, and the dispersion rate decreased with the increaseof salinity. Then, the effect of ANCC on the emulsion property, interfacetension, and expansion modulus of saponin solution was studied. Itcan be found from results that with the increase of ANCC concentration,the emulsion rate between saponin and crude oil increased, the waterextraction rate decreased, the emulsion particle size decreased, theinterface tension decreased, the expansion modulus increased, andthe emulsion stability became better. At the same time, with the increaseof temperature, the interface tension decreased, and the expansionmodulus increased. With the increase of salinity, the interface tensiondecreased first and then increased, and the expansion modulus decreased.Finally, the effect of ANCC on the oil recovery of saponin solutionflooding was studied by displacement experiments. It can be foundfrom results that when the ANCC concentration was 100, 500, and 1000ppm, the oil recovery was increased, respectively, by 18.42, 20.97,and 24.59%, indicating that the oil recovery gradually increased withthe increase of the concentration of ANCC. This work is of great significancefor enhanced oil recovery in surfactant flooding.