EGU22-6622
https://doi.org/10.5194/egusphere-egu22-6622
EGU General Assembly 2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.

Numerical investigation of the effects of chemical dissolution and mineral reaction on reservoir performances in CO2-plume geothermal systems 

Dejian Zhou, Alexandru Tatomir, and Martin Sauter
Dejian Zhou et al.
  • University of Goettingen, Geoscience Center, Applied Geology, Goettingen, Germany (dejian.zhou@geo.uni-goettingen.de)

The increasing emission of greenhouse gases and increasing demand for energy supply are reasons to investigate geothermal energy systems where scCO2 is the working fluid. However, the complex dissolution and reaction of minerals during the heat production processes affect the performance of geothermal reservoirs. Thus, a comprehensive numerical model that includes the Thermal-Hydraulic-Chemical (THC) coupled physical-chemical processes was implemented in the open-source simulator DuMuX, to model the phase displacement, chemical dissolution, heat transport, and mineral reactions. The aim is to investigate the influence of these parameters on the overall geothermal reservoir performance. More precisely, this study investigates the effects of salt precipitation, mineral reactions, injection rate, injection temperature, and geothermal reservoir size on heat production rate and scCO2 sequestration. The simulation results show that the scCO2- calcite reaction decreases the reservoir heat production rate but increase the sequestration of scCO2. Moreover, its effects are proportional to the scCO2 injection rate but inversely proportional to the geothermal reservoir size. On the other hand, the dissolution of scCO2 in brine has the same influence as the reaction between scCO2 and calcite, benefiting the CO2 sequestration but minimizing the heat production rate of the geothermal reservoirs. Furthermore, the sensitivity analysis presents that the influence of chemical dissolution and mineral reactions are only significant when the injection rate is large and the reservoir size is small.

How to cite: Zhou, D., Tatomir, A., and Sauter, M.: Numerical investigation of the effects of chemical dissolution and mineral reaction on reservoir performances in CO2-plume geothermal systems , EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-6622, https://doi.org/10.5194/egusphere-egu22-6622, 2022.

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