Temperature determination using thermo-sensitive tracers: Experimental validation in an isothermal column heat exchanger

The estimation of thermal drawdown and its spatial and temporal evolution is a major challenge in the context of geothermal reservoir management. Column experiments were performed with the aim of assessing the potential of thermo-sensitive tracers to measure prevailing in situ temperatures of the flowed-through medium. The results from 40 isothermal experiments with different residence times and temperatures using thermo-sensitive tracers are presented. The resulting precise temperature estimates were independent of the residence time and measured concentration. Considering pH, an accuracy of up to 1 K was achieved. The underlying theory was successfully verified and the general applicability proven.