纳米材料对CO₂泡沫体系的稳定作用及驱油效果评价

Effect of Nano Material on the Stability and Flooding Efficiency of CO₂ Foam

王爱蓉 吴清红 吴林勇 李华斌

WANG Airong WU Qinghong WU Linyong LI Huabin

泡沫与CO2交替驱可改善CO2驱在非均质性油藏中的应用效果，但高温对泡沫稳定性影响较大，降低了泡沫改善CO2驱的效果。为揭示纳米材料稳泡剂在高温条件下对泡沫性质的影响以及相应的驱油效果，采用高温高压泡沫评价装置（改进型的气流法），研究了不同稳泡剂对起泡剂起泡性能（20～120℃）和驱油效果（95℃）的影响。结果表明，改性纳米材料颗粒的润湿接触角为78°、粒径平均值为29.3 nm；泡沫体积受温度影响较小，泡沫半衰期随温度升高而迅速降低；纳米材料、部分水解聚丙烯酰胺（HPAM）和羧甲基纤维素钠（CMC）三种稳泡剂均能改善起泡剂的泡沫稳定性，其中改性纳米材料的效果最理想。驱油实验结果表明，在CO2驱中加入起泡剂和改性纳米材料稳泡剂可大幅提高采收率，水驱后CO2驱、泡沫与CO2交替驱以及添加改性纳米材料泡沫驱的采收率增幅分别为15.51%、26.94%和30.93%，改性纳米材料稳泡剂可进一步提高泡沫的稳定性和CO2泡沫体系的驱油效果。图6表2 参15

Foam alternating CO2 displacement improved the application effect of CO2 flooding in heterogeneous reservoir，but high temperature had a great impact on foam stability which reduced the improvement of CO2 flooding effect by foam. In order to reveal the influence of nano material foam stabilizer on foam properties and displacement efficiency at high temperature，high temperature and high pressure foam evaluation device（improved air flow method）was used. The effects of different foam stabilizers on the foaming properties（20—120℃）and displacement efficiency（95℃）of foaming agent were studied. The results showed that the wetting contact angle of modified nanoparticle was 78° and the average particle size was 29.3 nm. Meanwhile，foam volume was affected slightly by temperature，but the half-life time of foam quickly decreased with increasing temperature. Three types of foam stabilizers，including modified nano material，partially hydrolyzed polyacrylamide（HPAM）and carboxymethyl cellulose（CMC）， could improve the foam stability of foaming agent in high temperature condition，of which modified nano material had the best effect. Oil displacement experiment results showed that adding foaming agent and modified nano material foam stabilizer would significantly enhance the recovery ratio of CO2 flooding. The enhanced recovery ratio of CO2 flooding，foam alternating CO2 flooding and foam flooding adding modified nano material after water flooding was 15.51%，26.94% and 30.93% respectively. Nano material foam stabilizer could improve the stability of foam and the oil displacement efficiency of CO2 foam system.

10.19346./j.cnki.1000-4092.2017.01.017