A5042063440- Rock Mechanics and Modeling
- Hydraulic Fracturing and Reservoir Analysis
- CO2 Sequestration and Geologic Interactions
- Groundwater flow and contamination studies
- earthquake and tectonic studies
- Drilling and Well Engineering
- SMEs Development and Digital Marketing
- Hydrocarbon exploration and reservoir analysis
- Geothermal Energy Systems and Applications
- Mineral Processing and Grinding
- Financial Analysis and Corporate Governance
- Landslides and related hazards
- High-pressure geophysics and materials
- Dam Engineering and Safety
- Seismology and Earthquake Studies
Tohoku University
2019-2024
An enhanced geothermal system using carbon dioxide (CO2) for both reservoir creation and thermal energy extraction has attracted attention; however, studies on the CO2 fracturing of volcanic rocks under conditions are lacking. This study aimed to elucidate characteristics processes in via integrated lab-scale experiments numerical simulations basalt andesite at 250°C a confining pressure 30 MPa. Moreover, it proposed demonstrated an efficient CO2-based method based obtained insights....
Complex cloud-fracture networks, favorable for enhanced geothermal system reservoir development, were shown to be able achieved in granite under superhot conditions, with temperatures of approximately 400–500 °C, by injecting low-viscosity water at these temperatures. Nonetheless, utilization has several drawbacks, such as its reactivity rock-forming minerals. Carbon dioxide (CO2), which a low viscosity similar that the both and lower-temperature conventional is proposed replacement overcome...
Abstract Recent researches have proposed the use of enhanced geothermal system reservoirs consisting dense networks microfractures, created by hydraulic and/or thermal fracturing in superhot/supercritical environments, because their suitability for energy harvesting. During and extraction, fracture are exposed to cooling due injection cold fluid into reservoirs. Previous studies showed such reservoir permeability conventional environments. However, may result a higher risk seismicity, owing...
Developing high-enthalpy geothermal systems requires a sufficiently permeable formation to extract energy through fluid circulation. Injection experiments above water's critical point have shown that flow can generate network of highly conductive tensile cracks. However, what remains unclear is the role played by and solid rheology on dense crack network. The decrease viscosity with temperature thermally activated visco-plasticity in rock are expected change deformation mechanisms could...
Existing research indicates that to create geothermal reservoirs using CO2 injection, additional stimulation methods are necessary. N, N-bis(carboxymethyl)-L-glutamic acid (GLDA) injection has been predicted increase the permeability of injection-induced cloud-fracture networks (CFNs) and could serve as an method. Nevertheless, influence differential stress, flow geometry, scale on characteristics enhancement by GLDA is yet be clarified. Accordingly, this study experimentally elucidated...
Abstract This study elucidates the possibility of CO 2 injection-induced formation a complex cloud-fracture network (CFN) in granite, along with shearing (shear slip) natural pre-existing fractures under conventional (~ 150–300 °C) and superhot (> ~ 400 geothermal conditions, potentially providing additional connecting flow paths between stimulated fractures. Here, we conduct set experiments triaxial stress states at 150 °C 450 on cylindrical granite samples containing sawcut...
Previous studies showed that cloud-fracture networks (CFNs), of permeable microfractures densely distributed over rock body, formed in granite at superhot geothermal conditions (> ~400 °C) through the stimulation pre-existing by low-viscosity water near and above its critical temperature. The CFNs were also shown to form conventional (~150 – 300 injection CO2, same mechanism as conditions. CO2 implied may be matrix (i.e., unfractured rock) naturally-fractured...
<p>Creation of fractured reservoir for enhanced geothermal system (EGS) in granitic rock at unconventional superhot environments (>400°C) has been found possible by injection low viscosity supercritical water (Watanabe et al., 2017, Geoph. Res. Lett.; Watanabe 2019, Sci. Rep.). Accordingly, the complex cloud-fracture network is formed through stimulation pre-existing microfractures (<50 μPa∙s) water. Nonetheless, reactivity...
<p>Superhot geothermal environments with temperatures of approximately 400-500<sup>︒</sup>C at depth 2-4 km are expected as a new energy frontier. In order to efficiently exploit the superhot resources, fracture systems necessary flow path working fluid. Hydraulic fracturing is promising technique because it able create system or enhance permeability preexisting system. Laboratory-scale hydraulic experiments granite have demonstrated...