Construction of a Reactor for the Supply of Geothermal Fluids Under Laboratory Conditions (GECO Project)

Abstract

GECO (Geothermal Emission Control) is an international research project that started in 2018, funded by the EU through the H2020. Its core is the limitation of emissions from geothermal plants through the condensation and re-injection of gases. In Germany, the Bochum Metropolitain Underground Laboratories (MULE) are operated by the International Geothermal Centre (GZB). For GECO, GZB is testing the effects of injection of CO2-rich hydrothermal fluids on sedimentary reservoirs. The interactions of fluids and rocks or components under artificial reservoir conditions are quantified and qualified in pilot-plant scale. For this purpose, geothermal fluids at exact defined composition, pressure and temperature are provided by a geo-fluid / gas reactor (FGR). In this reactor, components such as Cl-, Na+, K+, Ca2+, Mg2+ or CO2 are added into a water flow loop. Furthermore, this arrangement, including a flow loop, allows precise control of the temperature, the pressure, as well as the mass flow due to constant pressure differences over a mass flow controller. Thus, the FGR can be operated in combination with experimental reactors as well as with boreholes.