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f Supercritical fluids and their properties for heat transmission and geochemical reactivity: example of the supercritical CO²
- Publisher: European Association of Geoscientists & Engineers
- Source: Conference Proceedings, 70th EAGE Conference and Exhibition - Workshops and Fieldtrips, Jun 2008, cp-41-00055
- ISBN: 978-94-6282-104-0
Abstract
The thermodynamic and thermophysical properties of supercritical carbon dioxide (CO2(sc))<br>are known and theoretical approaches are introduced in many numerical modeling codes.<br>Various studies have identified the key mechanisms of transport and the physical – chemical<br>behaviour of the field near the CO2(sc) injection wells in saline aquifers (André et al., 2007,<br>and therein references). The contrast of thermophysical properties between water and<br>carbon dioxide is sufficiently large to envisage the use of CO2(sc) as a heat transmission fluid<br>in the context of enhanced geothermal systems - EGS (Brown, 2000; Pruess, 2006; Pruess<br>and Azaroual, 2006; Pruess 2008). The carbon dioxide is a poor conductor of heat, low<br>density and low viscosity fluid but it still offers some properties flow quite attractive especially<br>because of its low viscosity and high buoyancy. It is also a bad solvent of solids and water.<br>Analysis of these thermodynamic functions reveals the complexity of the thermal perturbation<br>induced by the injection of CO2(sc) in the geothermal heat exchangers in which initial<br>conditions of temperature and pressure correspond to the field of supercritical CO2(sc).