This study is part of the DESTRESS project which follows the ambition to reliably increase system efficiency of enhanced geothermal systems (EGS). EGS uses artificial improvements of the hydraulic performance of a reservoir to allow a widespread usage of the huge untapped geothermal potential. The concept of chemical stimulation treatment of geothermal reservoirs has been developed by DESTRESS to optimize the EGS approach in a sustainable way and adapt it to the specific geological environments of Europe.
This study will focus on impacts of fluid-rock interaction on the rock properties. The experimental system can work in both recycling and single-pass mode. The recycling mode is desired for reactions approaching equilibrium, while the single-pass for reactions far-from-equilibrium. Continuing the previous work (A.J.Luhmann et al., 2014), we will conduct reactive flow-though experiments with core samples from different geothermal sites (Klaipeda, Vydmantai and Palange in Lithuania), observe the reaction process and the evolution of the rock structure, measure the elements concentration in the fluids, calculate the quantity of mineral dissolution and precipitationon and the changes in porosity, permeability, reactive surface area.
A.J. Luhmann and X.-Z. Kong and B.M. Tutolo and N. Garapati and B.C. Bagley and M.O. Saar and W.E. Seyfried Jr. Experimental dissolution of dolomite by CO2-charged brine at 100oC and 150 bar: Evolution of porosity, permeability, and reactive surface area, Chemical Geology, 380 pp.145-160 (2014)