驱油用水溶性乳化剂乳化性能的评价

The emulsifying performance evaluation of hydrophilic emulsifiers used for chemical flooding

结合改进后的水溶性乳化剂乳化力的测定方法以及现有乳化稳定性的评价方法,分别测定了驱油常用的磺酸盐类(阴离子型乳化剂)、甜菜碱类(两性离子型乳化剂)、聚氧乙烯烷基苯酚醚类(OP型,非离子型乳化剂)3类乳化剂的乳化力和乳化稳定性,并计算了乳化剂的乳化强度综合指数。探究了乳化剂类型与碳链长度对乳化剂乳化性能的影响,并着重分析了乳化剂浓度对其乳化性能的影响。结果表明,乳化剂疏水链中碳原子数相近时,甜菜碱类(两性离子型)乳化京-11原油的能力要优于磺酸盐类乳化剂(阴离子型)。当乳化剂疏水基含碳原子数与原油等效烷烃碳数相近时,同类型乳化剂的乳化性能随疏水链中碳原子数的增加而变弱;当两者相差较大时,乳化剂的乳化性能较差。其次,乳化剂的浓度越高,3种类型乳化剂的乳化稳定性均越强;当乳化剂浓度高于其CMC值时,乳化剂浓度对乳化剂的乳化力影响较小。

The emulsifying performance of three kinds of hydrophilic emulsifier including sulfonate surfactants （anionic emulsifier）, betaine surfactants（ amphoteric ionic emulsifier）and alkyl phenol polyoxyeth- ylene ether surfactants （nonionic emulsifier） used in chemical flooding were tested by improved determination method of emulsifying capability and the commonly used evaluation method of emulsification stability for emulsifiers. The emulsification intensity indexes of these emulsifiers were calculated. The effect of emulsifier types, the length of alkyl carbon chain in emulsifies and special the concentrations of emutsifies on the emulsifying performance were analyzed. Results showed that the betaine surfactants performed better than sulfonate surfactants in emulsifying the Jing-11 oil when these emulsifiers contain similar carbon atom numbers. For same type surfactants,if the carbon atom numbers in hydrophobic chain of emulsifier was close to the crude oil equivalent alkane carbon number （EACN）, the emulsifying performance becomes weaker as the carbon atom number increased;while emulsifying performance decreased when the gap between these two factors is increased. In addition, the emulsification stability of these three type emulsifiers become stronger as the concentrations of emulsifiers increased;However, the concentrations of emulsifiers have a little influence on the emulsifying capability when these concentrations are more than the CMC value.