Synthesis of temperature and salt resistance silicon dots for effective enhanced oil recovery in tight reservoir  

作　　者：Cheng Liu Biao Zhou Bing-Shan Wang Huan Wang Qing You Guang Zhao Cai-Li Dai 

机构地区：[1]Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering,China University of Geosciences,Beijing,100083,China [2]School of Energy Resources,China University of Geosciences,Beijing,100083,China [3]Chengdu Huayang Town Chengdu Natural Gas Chemical General Factory,Chengdu,610213,Sichuan,China [4]School of Petroleum Engineering,China University of Petroleum,Qingdao,266580,Shandong,China

出　　处：《Petroleum Science》2024年第5期3390-3400,共11页石油科学（英文版）

基　　金：the financial support from the National Natural Science Foundation of China (Nos. 52074249, 51874261, 52304011)。

摘　　要：The intensive development of tight reservoirs has positioned them as a strategic alternative to conventional oil and gas resources. Existing enhanced oil recovery(EOR) methods struggle to effectively exploring reservoir oil, resulting in low recovery rates. Novel and effective means of developing tight reservoirs are urgently needed. Nanomaterials have shown promising applications in improving water flooding efficiency, with in-depth research into mechanisms that lower injection pressure and increase water injection volumes. However, the extent of improvement remains limited. In this study, a silicon quantum dots(Si-QDs) material was synthesized via a hydrothermal synthesis method and used to prepare a nanofluid for the efficient recovery of tight reservoir. The Si-QDs, with an approximate diameter of 3 nm and a spherical structure, were surface functionalized with benzenesulfonic acid groups to enhance the performance. The developed nanofluid demonstrated stability without aggregation at 120℃ and a salinity of 60000 mg/L. Core flooding experiments have demonstrated the attractive EOR capabilities of Si-QDs, shedding light of the EOR mechanisms. Si-QDs effectively improve the wettability of rocks, enhancing the sweeping coefficient of injected fluids and expanding sweeping area.Within this sweeping region, Si-QDs efficiently stripping adsorbed oil from the matrix, thus increasing sweeping efficiency. Furthermore, Si-QDs could modify the state of pore-confined crude oil, breaking it down into smaller particles that are easier to displacement in subsequent stages. Si-QDs exhibit compelling EOR potential, positioning them as a promising approach for effectively developing tight oil reservoirs.

关 键 词：Silicon quantum dots Tight reservoir Microfluidic MICRO-CT Enhanced oil recovery Temperature and salt resistance 

分 类 号：TE357[石油与天然气工程—油气田开发工程]