Ke Gao's research while affiliated with Southwest Petroleum University and other places

Publications (9)

Article
Water-alternating-CO2 gas (WAG) flooding is a common technique to enhance oil recovery via improving CO2 sweep efficiency, but serious gas channeling may still occur, especially in reservoirs with strong heterogeneity, due to a poor blocking capacity of aqueous slugs to the “channeling” pathway induced by their low viscosity. Herein, a copolymer wh...
Conference Paper
The potential of CO2 injection in stimulating tight oil recovery after primary production has been extensively demonstrated previously. However, the processes of mass transport and exchange inside dual-permeability matrix-facture system driven by CO2 remain unclear. To improve our understanding and supplement the existing knowledge, three types of...
Article
CO2 offers potential for improving oil recovery of unconventional reservoirs. There is, however, a lack of understanding of mass transport in matrix-facture systems during CO2 injection to simulate hydraulically fractured formations. To bridge the gaps, three dual-permeability tight matrix-fracture models were designed and employed to mimic CO2 huf...
Article
Recent reports have demonstrated that carbon dioxide (CO2) injection can further raise the oil recovery of fractured tight reservoirs after natural depletion, with major projects in progress worldwide. There is, however, a lack of understanding of the mass-exchange process between the matrix and fracture at pore scale. In this study, a matrix (0.8...
Conference Paper
CO2 injection, either miscible or immiscible, has been recognized as a promising method to enhance oil production for tight reservoirs, with major projects in progress worldwide. This work targeted a tight sandstone reservoir in China, located in the Lucaogou formation of Jimsar sag, Junggar Basin. CO2 injection using huff-puff method was planned t...
Article
Recent reports have demonstrated that gas injection can improve oil recovery of tight reservoirs after natural depletion, with major projects in progress worldwide. There is however a lack of understanding of the gas displacement behaviors at pore-scale especially under reservoir conditions. Herein we conducted an experimental investigation of CO 2...
Conference Paper
In this work, a novel nano-suspension (NS), which was mainly composed of a surface functionalized nano-cellulose, was successfully developed for "green" chemical EOR use. The rheological analysis indicated that this NS was a pseudo-plastic (shear-thinning) fluid and presented noticeable viscoelasticity. The oil displacement behaviors of this NS wer...

Citations

... 249 Zheng and Sharma 266 successfully investigated the effects of geomechanical and phase behavior in H-n-P oil recovery. Recently, Wei et al. 267 conducted a quantitative study of the mass transport and exchange mechanisms caused by CO 2 injection in cracked tight cores. Three types of matrix−fracture systems have been created and utilized to mimic CO 2 injection procedures (H-n-P and flooding techniques). ...
... The injected CO 2 successfully infiltrated into the matrix to displace the crude oil, and the recovery rate in the dense core (0.85 md) increased by 8.2%. Luo et al. [156] added synthetic triblock tackifier polymer (f127-g-pdmaema) to water slug to control gas channeling during water-oil displacement. It is worth noting that the copolymer shows the synergistic thickening ability of heat/CO 2 and forms a stable gel above the gel temperature. ...
... Wei et al. [25] utilized NMR technique to monitor the oil distribution in the matrix and fracture and indicated that the mass transfer between the matrix and fracture proceeded to increase oil production intensively during the soaking time in the first cycle and contributed less in second and third cycles. In addition, the characteristics of produced oil also indicated that the presence of fracture can increase the CO 2 mass transfer between CO 2 and oil in the matrix [26]. As mentioned, the CO 2 recovery mechanisms and effects on the oil recovery factor in fractured tight oil reservoirs have been widely studied; and the mass transfer between CO 2 and oil in the near-fracture matrix also has been discussed through CT, NMR, and oil composition analysis. ...
... Lobanov [51] studied the phase behaviors of oil during CO 2 injecting in heavy oil and he found that when the concentration of injected CO 2 was 26 %, the extraction of oil components by CO 2 was the most pronounced, and the volume of the oil decreased. Based on the CO 2 huff and puff experiments, Wei [52] found that with the increase of huff and puff times, the components of the produced oil became lighter, and the heavy components and asphaltenes precipitation increased the viscosity and density of the remaining oil, which made it difficult to develop reservoirs in the later stage. ...
... Recently, quite a few experimental and numerical studies have been conducted to seek the optimum EOR methods for tight formations and attempt to reveal the underlying mechanisms such as CO 2 , solution gas, surfactant injection using huff-puff mode, etc. [4,[6][7][8]. Although exciting results can be easily obtained in laboratory, insufficient gas sources and costly operations often hinder the implementation of these technologies in oil fields especially in China. ...
... There are two modes of CO 2 combined with N 2 gas flooding (Wei et al., 2019;Hao et al., 2020;Bougre and Gamadi, 2021). One is to mix CO 2 and N 2 in a certain proportion to carry out mixed gas flooding; the other is slug flooding, that is, CO 2 and N 2 are injected periodically at different time periods. ...
... Another example is the Weyburn Oil Field, Saskatchewan, Canada. The Weyburn Oil Field is also one of the largest sites of monitored geological storage of CO 2 globally (Zhang et al., 2018). This storage site performed repeat 3D seismic surveys, fluid sampling, multiple soil gas sampling, shallow hydrology surveys, and passive seismic monitoring. ...
... Yuan et al. 60 2018 eight C 20 −C 54 alkanes HP-DSC Only one obvious oxidation reaction interval (LTO) was observed for C20−C54 alkanes oxidation, which is almost the same for all alkanes. Wei et al. 56 2018 heavy oil and SARA Yuan et al. 61 2019 alkanes and aromatics HP-DSC Tetracosane showed LTO, thioxanthone and p-quaterphenyl showed HTO, whereas pyrene showed M-HTO. Strong interaction was observed between tetracosane and aromatics during their co-oxidation. ...
... However, the calcite content of well B is much smaller than that of well A. Table 3 gives the detailed compositions of the three different fracture fluids in this study that are also widely used in the oilfield. Recently, environmentally friendly chemicals attract more attentions and the green IOR/EOR agents are investigated by a lot of researchers (Bing et al. 2018;Nasiru et al. 2020). ...