A High-Temperature-Resistant Nanogel for Profile Control and Water Shutoff in Deep Low-Permeability Reservoirs:...

The employment of profile control and water-shutoff agents in the context of high-temperature, low-permeability reservoirs has emerged as a pivotal strategy for augmenting oil recovery. However, the efficacy of reservoir modification is diminished by damage caused by low-temperature resistance and high filtration. The present study synthesized a profile-control agent (nanoscale) with the purpose of improving fluid flow in geological reservoirs. Furthermore, a multicoupled experimental apparatus was developed to evaluate the rheological, seepage, and plugging behaviors of geological fluids. In addition, a chemical kinetic model was established to elucidate the microscopic regulation mechanism of the profile-control and water-shutoff agent. The results demonstrated that the nanoscale chemical agent exhibited superior thermal stability compared with commercially available chemicals at 200 °C, while elevated reservoir pressure further enhanced its profile-control and water-shutoff performance. Moreover, the synthesized chemical agent showed lower filtration loss and reduced material adsorption relative to commercial products, thereby mitigating reservoir damage and improving reservoir recovery efficiency. This study provides fundamental theoretical and experimental support for energy extraction from high-temperature, low-permeability reservoirs.