Download or read book Modeling Brine rock Interactions in an Enhanced Geothermal Systemdeep Fractured Reservoir at Soultz Sous Forets France written by Karsten Pruess and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The modeling of coupled thermal, hydrological, and chemical (THC) processes in geothermal systems is complicated by reservoir conditions such as high temperatures, elevated pressures and sometimes the high salinity of the formation fluid. Coupled THC models have been developed and applied to the study of enhanced geothermal systems (EGS) to forecast the long-term evolution of reservoir properties and to determine how fluid circulation within a fractured reservoir can modify its rock properties. In this study, two simulators, FRACHEM and TOUGHREACT, specifically developed to investigate EGS, were applied to model the same geothermal reservoir and to forecast reservoir evolution using their respective thermodynamic and kinetic input data. First, we report the specifics of each of these two codes regarding the calculation of activity coefficients, equilibrium constants and mineral reaction rates. Comparisons of simulation results are then made for a Soultz-type geothermal fluid (ionic strength {approx}1.8 molal), with a recent (unreleased) version of TOUGHREACT using either an extended Debye-Hueckel or Pitzer model for calculating activity coefficients, and FRACHEM using the Pitzer model as well. Despite somewhat different calculation approaches and methodologies, we observe a reasonably good agreement for most of the investigated factors. Differences in the calculation schemes typically produce less difference in model outputs than differences in input thermodynamic and kinetic data, with model results being particularly sensitive to differences in ion-interaction parameters for activity coefficient models. Differences in input thermodynamic equilibrium constants, activity coefficients, and kinetics data yield differences in calculated pH and in predicted mineral precipitation behavior and reservoir-porosity evolution. When numerically cooling a Soultz-type geothermal fluid from 200 C (initially equilibrated with calcite at pH 4.9) to 20 C and suppressing mineral precipitation, pH values calculated with FRACHEM and TOUGHREACT/Debye-Hueckel decrease by up to half a pH unit, whereas pH values calculated with TOUGHREACT/Pitzer increase by a similar amount. As a result of these differences, calcite solubilities computed using the Pitzer formalism (the more accurate approach) are up to about 1.5 orders of magnitude lower. Because of differences in Pitzer ion-interaction parameters, the calcite solubility computed with TOUGHREACT/Pitzer is also typically about 0.5 orders of magnitude lower than that computed with FRACHEM, with the latter expected to be most accurate. In a second part of this investigation, both models were applied to model the evolution of a Soultz-type geothermal reservoir under high pressure and temperature conditions. By specifying initial conditions reflecting a reservoir fluid saturated with respect to calcite (a reasonable assumption based on field data), we found that THC reservoir simulations with the three models yield similar results, including similar trends and amounts of reservoir porosity decrease over time, thus pointing to the importance of model conceptualization. This study also highlights the critical effect of input thermodynamic data on the results of reactive transport simulations, most particularly for systems involving brines.

Download or read book Numerical study of physico chemical interactions for CO2 sequestration and geothermal energy utilization in the Ordos Basin China written by Hejuan Liu and published by Cuvillier Verlag. This book was released on 2014-11-10 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this dissertation, three simulators (i.e. TOUGH2MP, TOUGHREACT and FLAC3D) were used to simulate the complex physical and chemical interactions induced by CO2 sequestration. The simulations were done instages, ranging from the two phase (water and CO2) fluid flow (H2), through coupled hydro-mechanical effects (H2M) and geochemical responses (i.e. CO2-water-rock interactions (H2C)), to the extension of CCS to CCUS by the application of combined geothermal production and CO2 sequestration technologies. The findings of this study are essential for a thorough understanding of the complex interactions in the multiphase, multicomponent porous media controlled by different physical and chemical mechanisms. Furthermore, the simulation results will provide an invaluable reference for field operations in CCS projects, especially for the full-integration pilot scale CCS project launched in the Ordos Basin. Subsequently, a preliminary site selection scheme for the combined geothermal production and CO2 sequestration was set up, which considered various factorsinvolved in site selection, ranging from safety, economical, environmental and technical issues. This work provides an important framework for the combined geothermal production and CO2 sequestration project. However, further numerical and field studies are still needed to improve on a series of criteria and related parameters necessary for a better understanding of the technology.

Download or read book Comparing FRACHEM and TOUGHREACT for Reactive Transport Modelingof Brine rock Interactions in Enhanced Geothermal Systems EGS written by K. Pruess and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Coupled modelling of fluid flow and reactive transport ingeothermal systems is challenging because of reservoir conditions such ashigh temperatures, elevated pressures and sometimes high salinities ofthe formation fluids. Thermal hydrological-chemical (THC) codes, such asFRACHEM and TOUGHREACT, have been developed to evaluate the long-termhydrothermal and chemical evolution of exploited reservoirs. In thisstudy, the two codes were applied to model the same geothermal reservoir, to forecast reservoir evolution using respective thermodynamic andkinetic input data. A recent (unreleased) TOUGHREACT version allows theuse of either an extended Debye-Hu?ckel or Pitzer activity model forcalculating activity coefficients, while FRACHEM was designed to use thePitzer formalism. Comparison of models results indicate that differencesin thermodynamic equilibrium constants, activity coefficients andkinetics models can result in significant differences in predictedmineral precipitation behaviour and reservoir-porosity evolution. Differences in the calculation schemes typically produce less differencein model outputs than differences in input thermodynamic and kineticdata, with model results being particularly sensitive to differences inion-interaction parameters for highsalinity systems.

Download or read book Developing the Ability to Model Acid rock Interactions and Mineral Dissolution During the RMA Stimulation Test Performed at the Soultz sous For ts EGS Site France written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Clay Mineral Formation and Fluid rock Interaction in Fractured Crystalline Rocks of the Rhine Rift System written by Anja Maria Schleicher and published by . This book was released on 2005 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development Theories and Methods of Fracture Vug Carbonate Reservoirs written by Yang Li and published by Academic Press. This book was released on 2017-05-17 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development Theories and Methods of Fracture-Vug Carbonate Reservoirs explores the theories and methods for successful development of a fracture-vug reservoir by presenting the developmental strategies used in the Tahe oilfield. Some of the theories and methods of developing the Tahe fracture-vug reservoirs have been inspired by two China national research projects: The 'Basic research on development of fracture-vug carbonate reservoirs' (2006-2010), and the 'Basic research on production mechanism and oil recovery enhancement of fracture-vugcarbonate reservoirs' (2011-2015), with support by the National Basic Research Program of China. These theories and methods have facilitated the successful development of the fracture-vug reservoir in the Tahe oilfield, providing effective technologies and inspirations to developing similar reservoirs everywhere. - Provides information on both theoretical developments and technological innovations - Applies the modern karst formation characterization and the fracture-vug hierarchical structure to geological investigations of fracture-vug carbonate reservoirs - Introduces the karst facies-controlling 3D geologic modeling of fracture-vug reservoir formations - Proposes the coupled-processing and equivalent multi-medium numerical simulation methods of fracture-vug reservoirs - Presents development methodologies and techniques of water/gas flooding

Download or read book Fracture Network Modeling of a Hot Dry Rock Geothermal Reservoir written by Bruce A. Robinson and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transient Permeability in Porous and Fractured Sandstones Mediated by Fluid rock Interactions written by Chaojie Cheng and published by . This book was released on 2021* with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the fluid transport properties of subsurface rocks is essential for a large number of geotechnical applications, such as hydrocarbon (oil/gas) exploitation, geological storage (CO2/fluids), and geothermal reservoir utilization. To date, the hydromechanically-dependent fluid flow patterns in porous media and single macroscopic rock fractures have received numerous investigations and are relatively well understood. In contrast, fluid-rock interactions, which may permanently affect rock permeability by reshaping the structure and changing connectivity of pore throats or fracture apertures, need to be further elaborated. This is of significant importance for improving the knowledge of the long-term evolution of rock transport properties and evaluating a reservoir' sustainability. The thesis focuses on geothermal energy utilization, e.g., seasonal heat storage in aquifers and enhanced geothermal systems, where single fluid flow in porous rocks and rock fracture networks under various pressure and temperature conditions ...

Download or read book Impacts of Rock brine Interactions on Petrophysical Properties of a Sandstone Reservoir Utilizing Geochemical and Pore Network Modeling written by Masoud Safari-Zanjani and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation of Fractured Reservoir with Sorption and Applications to Geothermal Reservoir written by Kok-Thye Lim and published by . This book was released on 1995 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Formation Water Chemistry and Modeling of Fluid rock Interaction for Improved Oil Recovery in Aux Vases and Cypress Formations Illinois Basin written by Ilham Demir and published by . This book was released on 1995 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Discrete Fracture Model for a Hot Dry Rock Geothermal Reservoir written by Bruce A. Robinson and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Role of Fractures and Faults in Reservoirs written by Mando Guido Blöcher and published by . This book was released on 2022 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fractured Vuggy Carbonate Reservoir Simulation written by Jun Yao and published by Springer. This book was released on 2017-08-16 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book solves the open problems in fluid flow modeling through the fractured vuggy carbonate reservoirs. Fractured vuggy carbonate reservoirs usually have complex pore structures, which contain not only matrix and fractures but also the vugs and cavities. Since the vugs and cavities are irregular in shape and vary in diameter from millimeters to meters, modeling fluid flow through fractured vuggy porous media is still a challenge. The existing modeling theory and methods are not suitable for such reservoir. It starts from the concept of discrete fracture and fracture-vug networks model, and then develops the corresponding mathematical models and numerical methods, including discrete fracture model, discrete fracture-vug model, hybrid model and multiscale models. Based on these discrete porous media models, some equivalent medium models and methods are also discussed. All the modeling and methods shared in this book offer the key recent solutions into this area.

Download or read book Simulation of Fluid rock Interactions in a Geothermal Basin written by S. K. Garg and published by . This book was released on 1975 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Discrete Fracture Model for a Hot Dry Rock Geothermal Reservoir written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Modeling results are presented for the Fenton Hill Phase II reservoir using a two-dimensional steady state simulator of fluid flow and solute transport in fractured porous media. Fluid flow and tracer response data are simulated using a fracture flow model in which the fracture apertures are string functions of pressure. The model is used to match the available steady state data of pressure drop versus flow rate and the tracer data. Various schemes for improving reservoir performance, such as high backpressure, chemical etching, stimulation using a viscous fluid, and the drilling of a second production wellbore, are then examined. 15 refs., 7 figs., 4 tabs.

Download or read book Investigation of Stimulation Response Relationships for Complex Fracture Systems in Enhanced Geothermal Reservoirs written by and published by . This book was released on 2011 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: