Preparation and Properties of Inverse Emulsion Used for Water Shutoff in Oilfields
Zhao Yongfeng Xiong Jinping Zuo Yu(School of Materials Science and Engineering ,Beijing University of Chemical Technology,Beijing 100029)
Nano-particle stabilized inverse emulsion used for selective water shutoff in oilfields was prepared using diesel,emulsifier,and nano-silicon dioxide as main materials. The effects of various factors on its properties were investigated. The experimental results indicated that there was little effect of emulsifier dosage on emulsion viscosity,and the suitable dosage of emulsifier was 2% based on the mass of oil. The emulsion viscosity increased with the increase of the dosage of nano-particles in oil phase and while the content of silicon dioxide in oil phase was less than 0.2%,the viscosity of emulsion increased with the rise of temperature.The viscosity-temperature profile would be changed immediately by adding a small amount of the nano-particles of silicon dioxide in oil phase. The emulsion viscosity could be adjusted by altering the volume ratio of oil-water and would increase rapidly when the ratio of oil-water was more than 4 :1.The addition of NaCl in the emulsion gave rise to the viscosity increase of emulsion with the increase of temperature.