GeoProp: A thermophysical property modelling framework for single and two-phase geothermal geofluids

The techno-economic evaluation of geothermal resources requires knowledge of the geofluid's thermophysical properties. While the properties of pure water and some specific brines have been studied extensively, no universally applicable model currently exists. This can result in a considerable degree of uncertainty as to how different geothermal resources will perform in practice. Geofluid modelling has historically been focused on two research fields: 1) partitioning the geofluid into separate phases, and 2) the estimation of the phases’ thermophysical properties. Models for the two fields have commonly been developed separately. Recognising their potential synergy, we introduce GeoProp, a novel geofluid modelling framework, which addresses this application gap by coupling existing state-of-the-art fluid partitioning simulators, such as Reaktoro, with high-accuracy thermophysical fluid property computation engines, like CoolProp and ThermoFun. GeoProp has been validated against field experimental data as well as existing models for some incompressible binary fluids. We corroborate GeoProp's efficacy at modelling the thermophysical properties of geothermal geofluids via a case study on the heat content of different geofluids. Our results highlight the importance of accurately characterising the thermophysical properties of geofluids in order to quantify the resource potential and optimise the design of geothermal power plants