摘要
为解决低渗透油藏CO_(2)驱气体窜流影响开发效果的问题,以泡沫综合值为评价指标,通过搅拌法优选发泡剂,建立了CO_(2)响应性增强泡沫体系,配方为0.1%发泡剂AOS+4.0%小分子胺+水。该体系在接触CO_(2)前黏度与水接近,与CO_(2)作用后黏度可升高18倍以上。性能评价结果显示:CO_(2)响应性增强泡沫体系的泡沫综合值可达到常规泡沫体系的11倍以上;具有明显的剪切稀释特性,流变方程符合幂律流体流变模式;比常规泡沫体系具有更强的黏弹性,可以封堵优势渗流通道,抑制非均质低渗透油藏CO_(2)驱气体窜流,提高低渗透油藏CO_(2)驱的采收率。研究结果表明,CO_(2)响应性增强泡沫体系可以解决低渗透油藏CO_(2)气体窜流问题,提高CO_(2)驱的开发效果。
The development effect of CO_(2) flooding in low permeability reservoirs is affected by the gas channeling.In response to this problem,the foam comprehensive value was used as the evaluation index to establish CO_(2) responsive enhanced foam system by optimizing foaming agent with stirring method.The formula was 0.1%foaming agent AOS(alpha olefin sulfonate)adding 4.0%small molecule amine and water.Its viscosity,which was close to water viscosity before exposure to CO_(2),increased by more than 18 times after reaction with CO_(2).The results of performance evaluation indicated the foam comprehensive value of the proposed CO_(2) responsive enhanced foam system could reach more than 11 times those of conventional foam systems,with obvious shear-thinning characteristics.The rheological equation conformed to the rheological model of power-law fluids.With stronger viscoelasticity than those of conventional foam systems,the proposed foam system could also be used to plug the dominant seepage channels to inhibit the gas channeling during CO_(2) flooding in heterogeneous low permeability reservoirs and ultimately to enhance the oil recovery in such reservoirs.The research results showed that the CO_(2) responsive enhanced foam system could solve the problem of gas channeling and improve the development effect of CO_(2) flooding in low permeability reservoirs.
作者
吕伟
刘笑春
白海龙
彭明兰
LYU Wei;LIU Xiaochun;BAI Hailong;PENG Minglan(Oil and Gas Technology Research Institute,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi,710018,China;Engineering Technology Management Department,PetroChina Changqing Oilfield Company,Xi’an,Shaanxi,710018,China;The No.2 Oil Production Plant,PetroChina Changqing Oilfield Company,Qingyang,Gansu,745100,China)
出处
《石油钻探技术》
CAS
CSCD
北大核心
2021年第5期88-93,共6页
Petroleum Drilling Techniques
基金
国家科技重大专项“长庆低渗透砂岩油藏CO_(2)驱油与埋存注采工艺配套”(编号:2016ZX05056002)
中国石油重大科技专项“CO_(2)驱油与埋存注采配套技术研究”(编号:2014E-3603)联合资助。
关键词
低渗透油藏
二氧化碳驱
窜流
泡沫
提高采收率
low permeability reservoir
CO_(2)flooding
channeling
foam
enhanced oil recovery
