非离子表面活性剂对污水聚合物热稳定性的影响

针对聚/表二元复合驱体系的长期热稳定性问题，在污水配制的聚合物溶液中加入非离子表面活性剂，研究其长期热稳定性及降低油水界面张力的程度。配制聚合物浓度为2 000 mg/L，非离子表面活性剂质量分数为0.10%和0.20%，在53 ℃无氧条件下恒温60 d。结果表明，非离子表面活性剂加入后，黏度保留率由22.3%提高到71.4%，恒温60 d后油水界面张力仍然保持在10?3数量级。现场采用该体系进行试注后发现，注入液可将油水界面张力降至2.59×10?3 mN/m；在油藏条件下，溶液经60 d老化后其黏度保留率达到72%；注入井注入压力较注聚/表二元体系前上升1 MPa。

Analysis of the experimental study on nonionic surfactant effect to thermal stability of polymer mixed by produced water

To keep the thermal stability of polymer-surfactant dual-compound systems for a longer period.Some type of nonionic surfactant(0.10~0.20 wt%) is added to the polymer solution(2000 mg/L) diluted by produced water,and then,the system was aged for 60 days at 53 ℃ under the oxygen-deprived conditions.Following that,the thermal stability and the extent of reducing water-oil interface tension of the system were evaluated.The results showed that,after adding the surfactant and aging for 60 days,viscosity retention rate is improved from 22.3% up to 71.4%,and the water-oil interface tension is still within the order of 10 3 mN/m.The tentative practice which adopts this system to tentatively inject the solution combine polymer and surfactant into the reservior suggests that it reduce the water-oil interface tension down to the grade of 2.59×10 3;the viscosity of the solution remains the rate of 72%,even if the solution is kept in the same 53 ℃ for about 60 days;and the injection pressure enhances 1 MPa compared with the former conditions.