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Table 3 Relevant ion concentrations of the injected tap (’tap water DGF’) and aquifer water used in the field experiment, and the tap water used in the autoclave experiments (’tap water MUC’)

From: Crystallization of calcium carbonate in a large-scale push–pull heat storage test in the Upper Jurassic carbonate aquifer

ParameterTap water DGFAquifer waterTap water MUC
T, \(^{\circ }\hbox {C}\)132319
pH, -7.437.017.61
Redox, mV\(-\)253\(-\)146\(-\)264
TDS,mg/L525922391
\(\hbox {Na}^{+}\), mmol/L0.187.70.16
\(\hbox {K}^{+}\), mmol/L0.020.400.02
\(\hbox {Ca}^{2+}\), mmol/L1.91.11.9
\(\hbox {Mg}^{2+}\), mmol/L1.40.970.75
\(\hbox {Ba}^{2+}\), mmol/L0.00020.00170.0003
\(\hbox {Sr}^{2+}\), mmol/L0.00180.0110.016
\(\hbox {Zn}^{2+}\), mmol/L0.000010.002070.00028
\(\hbox {Cl}^{-}\), mmol/L0.404.10.16
\(\hbox {NO}_{3}^{-}\), mmol/L0.25\(<0.0016\)0.09
\(\hbox {SO}_{4}^{2-}\), mmol/L0.130.210.41
\(\hbox {HCO}_{3}^{-}\), mmol/L5.77.74.6
Mg/Ca0.720.880.39
p(\(\hbox {CO}_{2}\)), bar0.0380.0350.009
SI calcite− 0.19− 0.190.16
SI aragonite− 0.35− 0.330.02
SI vaterite− 0.79− 0.76− 0.43
  1. The calculated partial pressures of \(\hbox {CO}_{2}\) and SI are listed below (tap water for \({T} = 20\,^{\circ }\hbox {C}\) and \({p}_{\mathrm{total}} = 1\,\hbox {bar}\); aquifer water refers to reservoir conditions)