Physico Chemical Monitoring Tests of Geothermal Water Production Wells

This paper presents a study of the physico-chemical properties of geothermal fluids, coming from some wells in Sacuieni, Bihor County, Romania. The thermal energy of the geothermal waters studied is used for heating some industrial buildings, greenhouses, and administrative buildings. Continuous monitoring of physical and chemical characteristics of geothermal waters is needed. Based on this fact, a classification of these waters has been made according to their chemical composition. Using a silica-enthalpy thermodynamic model, it was possible to estimate the deep reservoir temperature, and compare it with the temperatures at depth, calculated by the silica (quartz and chalcedony) and Na+/K+ geothermometers. The WATCH program is used to estimate the mineral deposits that may accumulate due to boiling and cooling of the geothermal fluid when it is used in heat exchangers The results are confirmed by XRD spectrometric and thermogravimetric analyses.