摘要
针对传统的无机碱/表面活性剂/聚合物三元复合驱油体系容易对地层造成结垢堵塞和采出液后续处理及排放较困难等问题,使用与地层水配伍性较好的有机碱和低毒、易生物降解以及价格低廉的生物表面活性剂为主要处理剂,研制了一种新型低伤害有机碱三元复合驱油体系,并对其综合性能进行了评价。结果表明:新型低伤害有机碱三元复合驱油体系具有较低的界面张力,老化90 d后界面张力仍能维持在0.0044 mN/m;驱油体系与原油形成的乳状液稳定性较强,在60℃下放置120 min析水率为33.6%,放置24 h电动电位仍能达到-73.5 mV;驱油体系具有良好的抗吸附性能,吸附5次后界面张力仍能维持在0.0093 mN/m;驱油体系的生物毒性较低,EC_(50)值可以达到58450 mg/L,并且易生物降解,BOD_(5)与COD_(cr)比值可以达到34.6%,环保性能良好。实践证明,新型低伤害有机碱三元复合驱油体系的驱油效果较好,在岩心水驱后注入0.5 PV三元复合驱油体系后能使采收率继续提高25.5%以上,在三次采油方面具有较好的应用前景。
In view of the problems of traditional ASP flooding system easy to cause scaling and blocking damage to formation and difficult to subsequently treat and discharge produced fluid,organic alkali with good compatibility with formation water and low toxicity,biodegradable and low-cost biosurfactants are used as main treatment agent to develop a new type of low-damage organic alkali ASP flooding system and evaluate its comprehensive performance.The results show that the new ASP flooding system has lower interfacial tension,and the interfacial tension can still maintain at 0.0044 mN/m after 90 days of aging.The emulsion formed by displacement system and crude oil has high stability.Water syneresis rate is 33.6%after 120 min at 60℃,and Zeta potential can still reach-73.5 mV after placed for 24 hours.The system has good anti-adsorption performance,and interfacial tension can still maintain at 0.0093 mN/m after adsorbed for 5 times.Biological toxicity of the system is lower,EC_(50)value can reach 58450 mg/L and easily to be biodegraded,BOD_(5)/COD_(cr)value can reach 34.6%,and environmental protecting performance is good.Practice shows that the new low-damage organic alkali ASP flooding system has better oil displacement effects.After core waterflooding,oil recovery can be furtherly enhanced by more than 25.5%after injecting 0.5 PV ASP flooding system,therefore the new system has better application prospect in tertiary oil production.
作者
闫强伟
韩创辉
李文娟
YAN Qiangwei;HAN Chuanghui;LI Wenjuan(Xi’an Changqing Chemical Group Co Ltd,Xi’an 710000,China)
出处
《大庆石油地质与开发》
CAS
北大核心
2023年第1期115-122,共8页
Petroleum Geology & Oilfield Development in Daqing
基金
国家科技重大专项“低渗透油藏提高采收率新方法与关键技术”(2017ZX05013)。
