Environmental Sciences Seminar Series – Dr Francesco Parisio
11th December 2018
Dr Francesco Parisio (Computational Energy Systems, Department of Environmental Informatics, Helmholtz Centre for Environmental Research GmbH – UFZ, Germany) will give a seminar within “Environmental Sciences Seminar Series” of IDAEA.
Title: Geomechanical challenges in supercritical geothermal systems
Supercritical geothermal systems (SCGS) can achieve power production up to one order of magnitude higher compared to more traditional vapor dominated geothermal systems. The high temperature environment poses incredible challenges that are currently under investigation in research projects located in active volcanic areas such as Kakkonda in Japan, Taupo Volcanic Area in New Zealand, Larderello in Italy, Krafla and Reykjanes in Iceland, The Geysers and Salton Sea in USA and Los Humeros in Mexico. Open problems, like the rheology of the rocks and fluids at high temperature and their reciprocal interaction, translate into fundamental research questions, such as: does the rock behaves in a brittle or ductile manner? The answer bears important consequences in terms of seismic behavior, fracturing, wellbore stability and other geomechanical issues.
The seminar will explore some of the most recent research carried out at UFZ on geomechanics of supercritical geothermal systems.Firstly, a model for the brittle-ductile transition of different rocks (limestone and basalt) will be presented, along with its implementation in OpenGeoSys using the automatic code generator for mechanical behavior MFront. Results are compared with experimental evidence from laboratory measurements and in situ data of seismicity. The second part of the talk is dedicated to thermo-hydro-mechanical numerical simulations of injection scenarios in supercritical geothermal systems, taking into account porosity dependent permeability and full range of EOS of water. The mechanical stability of the system is studied in terms of potential for induced seismicity and the rate of seismic production model is applied to the scenario under consideration. Finally, the talk is concluded with a brief discussion on future research perspectives and outlooks.
Place: Sala d’Actes del CID-CSIC – C. Jordi Girona 18-26, 08034-Barcelona