摘要
致密油藏孔隙度小、渗透率低,常规表面活性剂无法进入孔喉中有效驱替原油,采用微乳液法将表面活性剂、油相和水相等合成的纳米乳液,具有纳米级粒径且吸附量低,可通过渗吸吸附的方式进入致密储层深部提高致密油藏采收率。为明确纳米乳液的吸附与渗吸驱油特性,通过紫外分光光度计,研究了不同粒径的天然砂岩与页岩岩粉对纳米乳液的静态吸附性能;并通过渗吸驱油实验研究各种因素影响下纳米乳液渗吸驱油规律,最终确定影响纳米乳液渗吸驱油效果的主控因素,为提高致密油藏开采效果提供理论依据。研究结果表明,不同目数的岩粉对纳米乳液的吸附性能存在一定差异,目数越大,岩粉比表面越大,对应吸附量越多,纳米乳液在页岩表面吸附量高于砂岩;相比于其他因素,纳米乳液种类、浓度及储层岩性对纳米乳液渗吸驱油效果影响最大,其次为岩心长度和实验温度。动态驱替实验结果表明,阴非离子型纳米乳液C具有较好的提高采收率效果,增幅达9.45%,其次为阴离子型纳米乳液A,增幅为8.98%,而阳离子纳米乳液B的效果最差,增幅为4.24%。
Due to the small porosity and low permeability of tight reservoirs,conventional surfactants cannot effectively displace crude oil in pore-throat.Nano-emulsion,which is equal to surfactant,oil phase and water by microemulsion method,has nano-sized particle size and low adsorption capacity,and can be used to enter deep tight reservoirs through imbibition adsorption to improve the recovery efficiency of tight reservoirs.In order to clarify the adsorption and imbibition displacement characteristics of nano-emulsion,the static adsorption properties of natural sandstone and shale rock powder with different particle sizes on nano-emulsion were studied by ultraviolet spectrophotometer.Through imbibition displacement experiment,the law of nano emulsion imbibition displacement under the influence of various factors was studied,and the main controlling factors affecting the effect of nano emulsion imbibition displacement were finally determined,which provided a theoretical basis for improving the production effect of tight reservoir.The results show that the adsorption performance of rock powder with different mesh number is different to some extent.The larger the mesh number is,the larger the specific surface of rock powder is,the more the corresponding adsorption capacity is.The adsorption capacity of nano-emulsion on shale surface is higher than that of sandstone.Compared with other factors,nanometer emulsion type,concentration and reservoir lithology have the greatest influence on the imbibition displacement effect of nanometer emulsion,followed by core length and experimental temperature.The dynamic displacement experiment results show that the negative nonionic nano emulsion C has a better EOR effect,with an increase of 9.45%,followed by anionic nano emulsion A,with an increase of 8.98%,and cationic nano emulsion B has the worst effect,with an increase of 4.24%.
作者
汪杰
罗旭
曾建国
江厚顺
贺东洋
WANG Jie;LUO Xu;ZENG Jianguo;JIANG Houshun;HE Dongyang(Cooperative Innovation Center of Unconventional Oil and Gas(Yangtze University),Wuhan 430100,Hubei;School of Petroleum Engineering,Yangtze University,Wuhan 430100,Hubei;Key Laboratory of Drilling and Production Engineering for Oil and Gas,Hubei Province(Yangtze University),Wuhan 430100,Hubei;Offshore Engineering Company Limited,CNPC,Beijing 100028;Manufacturing Company,China National Logging Corporation,Xi’an 710005,Shaanxi)
出处
《长江大学学报（自然科学版）》
2023年第4期66-73,共8页
Journal of Yangtze University(Natural Science Edition)
基金
油气钻采工程湖北省重点实验室开放基金项目“致密油藏水力压裂用纳米乳液渗吸增产机理及影响因素研究”(YQZC202202)
湖北省科学技术厅计划项目“纳米排驱剂解除涪陵页岩气藏水锁损害机理研究”(2021CFB249)
湖北省教育厅科学技术研究项目“纳米排驱剂解除致密砂岩气藏水锁损害机理研究”(Q20211303)。
关键词
致密油藏
纳米乳液
静态吸附
渗吸驱油
驱油效率
tight reservoir
nano emulsion
static adsorption
imbibition oil displacement
oil displacement efficiency
