原油乳状液的稳定性及其流变性

Research on the Relationship between the Stability and the Rheological Properties of Emulsion

王 涛 张志庆 王 芳 冯丽娟 杨 姗

WANG Tao ZHANG Zhi-Qing WANG Fang FENG Li-Juan YANG Shan

配制了一系列油水比不同的原油乳状液,并考察了原油乳状液的黏度和黏弹性。结果表明：原油乳状液含水率越大，分散相液滴体积越小，原油乳状液的黏度越大；当含水率低于30%时，原油乳状液呈现牛顿流体行为，黏度随温度和剪切速率的变化不是很明显；含水率超过30%时，原油乳状液呈现非牛顿流体行为，黏度随温度和剪切速率的变化较明显；含水率越大，原油乳状液的线性黏弹区越小，结构越不稳定，乳状液也越不稳定；加入破乳剂后，原油乳状液的黏度降低；含水率越大，原油乳状液脱水率越大，乳状液越不稳定。

A series of emulsion with different water-oil ratio were prepared， and the viscosity and viscoelasticity of the emulsion were measured. The results showed that the emulsions with more water cut had larger droplet and had a relatively larger viscosity than that with lower water cut. The emulsions showed the characteristics of Newtonian fluid when water content was less than 30%, the viscosity change little with temperature and share rate. When water content was more than 30%, the emulsion showed the characteristics of non-Newtonian fluid, the viscosity change obviously with temperature and share rate. The viscoelasticity of emulsion had a relationship with water cut. Emulsion with higher water cut had a smaller linear viscoelastic region and a more unstable structure. According to the rheological experiment, the addition of demulsifiers could reduce the viscosity of crude oil emulsion, moreover, the emulsion with higher water cut had better demulsification efficiency.